Integrated Surveillance for Lymphatic Filariasis and other Infectious Diseases with a Nationwide Non-Communicable Disease STEPwise Survey in the small Pacific Island Nation of Niue, 2025

Integrated Surveillance for Lymphatic Filariasis and other Infectious Diseases with a Nationwide Non-Communicable Disease STEPwise Survey in the small Pacific Island Nation of Niue, 2025 | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Integrated Surveillance for Lymphatic Filariasis and other Infectious Diseases with a Nationwide Non-Communicable Disease STEPwise Survey in the small Pacific Island Nation of Niue, 2025 Adam Craig, Harriet Lawford, Grizelda Mokoia, Patricia Tatui, and 7 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8726246/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 9 You are reading this latest preprint version Abstract The small Pacific island nation of Niue was validated by the WHO in 2016 as having eliminated lymphatic filariasis (LF) as a public health problem; however, no post-validation surveillance (PVS) has been conducted since. In 2025, LF-PVS was integrated into a near-census national WHO STEPwise non-communicable disease (NCD) risk factor survey, a cost-effective approach for estimating LF prevalence and assessing whether elimination had been sustained. Finger-prick blood samples were tested for LF antigen and antibodies; antigen-positive samples were screened for microfilariae. One participant was antigen-positive (0.1%, 95% CI 0.02–0.88), and no microfilariae were detected, indicating sustained elimination. Ten participants were antibody-positive (five Wb123 , four Bm14 , one dual-positive). Semi-structured interviews provided operational insights, indicating that integrating LF-PVS into the programme was resource-efficient, logistically feasible, and acceptable to both health workers and the community. This study is the first to demonstrate integrated NCD–communicable disease surveillance in the Pacific. Health sciences/Diseases Health sciences/Health care Biological sciences/Immunology Health sciences/Medical research Biological sciences/Microbiology Pacific Islands neglected diseases epidemiology public health surveillance Figures Figure 1 Figure 2 Figure 3 Introduction Lymphatic filariasis (LF) is an infection spread by mosquitoes and caused by three filarial worm species: Wuchereria bancrofti , Brugia malayi and B. timori 1 , 2 . Around 90% of global LF cases are due to W. bancrofti , which is also the only species present in Pacific Island countries and territories 3 . Transmission occurs when an infected mosquito bites a person, introducing larvae that travel to the lymphatic vessels. There, the parasites develop into adult worms and, if fertilised, produce large numbers of microfilariae (Mf) that circulate in the blood. Most infections begin with no noticeable symptoms 4 , though people may experience episodes of acute inflammation such as dermatolymphangioadenitis or filarial lymphangitis [5]. If left untreated, chronic immune responses to the adult worms can lead to bacterial superinfection and long-term lymphatic dysfunction, resulting in conditions such as lymphoedema, elephantiasis and scrotal hydrocele 5 . LF remains a public health issue in 72 countries 6 , and in 2019 it was estimated to account for 1.63 million disability-adjusted life-years 7 , 8 . The 1997 World Health Assembly called for the global elimination of LF as a public health problem, prompting the establishment of the Global Programme to Eliminate Lymphatic Filariasis (GPELF) in 2000 9 . The programme set a target to achieve global elimination by 2020 through surveillance, Mass Drug Administration (MDA), and Morbidity Management and Disability Prevention (MMDP). Although this goal was not met, momentum has continued. In 2021, the World Health Organization released the updated Roadmap for Neglected Tropical Diseases for 2021–2030, which sets out the expectation that by 2030 all 72 LF-endemic countries will have stopped MDA and will be conducting either post-validation (PVS) or post-MDA surveillance activities 10 . At the country level, elimination of LF as a public health problem is validated by the World Health Organisation (WHO). Countries that achieve validation are encouraged to implement PVS to ensure early detection of any resurgence. Guidance on PVS design, frequency, and duration has been limited, leading to inconsistent implementation and, in many countries, inactivity following validation of elimination. This gap has, in part, been addressed in the 2025 WHO publication entitled Monitoring and epidemiological assessment of mass drug administration in the global programme to eliminate lymphatic filariasis: a manual for national elimination programmes, 2nd ed 11 . Niue is a small (261 km 2 ) self-governing island in the South Pacific, located approximately 660 km southeast of Samoa and 2,400 km northeast of New Zealand (19°S, 169°W). The island has a population of ~ 1,600 people (about 1,300 of whom are on the island at any one time, though this fluctuates) (Fig. 1 ) 2 , 12 . LF surveys have been conducted in Niue since 1954. In the 1954 population-wide survey, Mf prevalence was found to be 22.2% 13 . Between 1955 and 2005, eight rounds of MDA were implemented, resulting in a reduction in antigen (Ag)-positive prevalence to 0.5% by 2009 2,14 (Fig. 2 ). In October 2016, Niue was validated by WHO as having eliminated LF as a public health problem 15 and the country officially moved into a post-validation phase. Until the present study, no PVS or community surveillance for LF had been conducted. In 2025, an integrated approach to LF-PVS was undertaken, where PVS was embedded into a planned and funded national WHO STEPwise non-communicable disease (NCD) risk factor (STEPS) survey that, in addition to asking NCD-related lifestyle, diet, and behavioural questions, collected finger-prick blood samples from participants to test for blood glucose and blood cholesterol levels 2 . Here, we present the results of the LF-PVS survey and discuss the benefits, enablers, challenges, and adaptive practices required to successfully integrate LF-PVS into a routine national public health program. Methods This study had two aims. First, it sought to conduct the first PVS in Niue nine years after the country was validated as having eliminated LF as a public health problem and thereby assess whether the elimination status had been maintained. Second, it aimed to explore critical operational dynamics that support or hinder integrated approaches to LF-PVS in a Pacific Island setting, with the intention of generating practical guidance for other countries and regions seeking cost- and labour-efficient models for PVS implementation. Lymphatic filariasis Post-Validation Surveillance (Aim 1) Pre-survey community engagement In the weeks prior to the survey, the Niue Department of Health (DoH) Public Health Unit undertook community awareness activities, including village talks, radio broadcasts and talk-back sessions, and social media messaging. These activities raised awareness of the STEPS and LF-PVS surveys, explained the procedures, and clarified how the collected data would be used and reported. Participant recruitment The LF-PVS was conducted as a population census of individuals aged >3 years. To achieve this, two recruitment methods were used. First, LF-PVS was integrated with a planned national population-based WHO STEPS survey. Integration between the LF-PVS and STEPS occurred at multiple points in the workflow, including during pre-survey community engagement, when obtaining informed consent, during the collection of survey-based data, and during the collection of finger-prick blood samples to test for cholesterol, glucose, and LF Ag and antibodies (Ab) to multiple pathogens. The STEPS survey’s target population were all people aged 16 to 69 years, and the survey was conducted from 24 February to 4 April 2025. STEPS surveying was conducted in community halls and churches across the 14 villages in Niue. This approach is outlined in a published methods paper 2 . Second, to expand the age range of PVS participants to include younger (3 to 16 years) and older (> 69 years) participants, convenience community-based sampling was used. Community-based sampling was conducted at the country’s only primary and high school, the morning market, the bank waiting area, workplaces, churches, and the outpatient clinic at Niue Foou Hospital. Each participant was allocated a unique QR-coded identifier, which was affixed to all study materials (consent forms, questionnaires, blood collection tubes, Bioline TM Filariasis Test Strip (FTS) (Abbott, Scarborough, ME), slides, and dried blood spots (DBS) [see below] to support linkage and tracking. Field logistics, demographic, and travel history data collection At each STEPS survey site, participants moved through three ‘stations.’ First, at a dedicated ‘registration and consent station,’ participants provided demographic information (age, sex, country of birth, village of residence, occupation) and gave written consent to participate in both the STEPS and/or LF-PVS studies (participants could opt in/out of either study). Second, participants proceeded to ‘blood collection stations,’ where at least 300μL of finger-prick blood was collected into heparin-coated BD Microtainers® Blood Collection Tubes and stored in a cooler box for later LF testing and DBS preparation (as part of LF-PVS) at a field laboratory. Third, participants attended an ‘interview station’ where questions on international travel history were embedded in the standard STEPS questionnaire to collect data on participants’ travel to LF-endemic countries. Data were captured in a standardized from developed by WHO and collected through a purpose-built ODK platform For samples collected through community-based sampling, consent, blood collection, and LF-related risk questions were completed at a single station. EpiCollect5 software (v76.1.0; https://five.epicollect.net/) was used to collect and to link STEPS and community sampling data. Lymphatic filariasis laboratory testing For each participant, blood samples were tested for LF Ag using FTS. For any Ag-positive samples, Mf slides were prepared using methods described previously 16 and read independently by two trained microscopists in Australia. Household members and those residing within 100m of any Ag-positive person were followed up and, if not already done, LF Ag testing was offered. For all participants, DBS were collected onto Cellabs Tropbio Filter Paper Blood Collection Disks™ (up to 6 x 10 μL spots) for multiplex bead assay (MBA) analysis using Luminex® technology to detect Ab for a panel of infectious diseases, including two Abs for LF ( Wb123 and Bm14 ) 17 . Statistical analysis Data were analysed using Stata (Version 19.0; StataCorp, College Station, TX). Descriptive statistics were generated for Ag and Ab results, and 95% confidence intervals were computed for relevant demographic variables, including age, sex, and village of residence. Dynamics that support integrated approaches to LF-PVS (Aim 2) Data collection Three sources of data related to the dynamics that supported integrated PVS were collected. First, field observations of the LF-PVS team were collected through daily and end-of-survey debriefing sessions. Second, key informant interviews were conducted with purposefully selected Niue DoH staff directly involved in implementing the integrated STEPS/LF-PVS approach. And third, a micro-costing analysis (which has been published elsewhere 18 ) was performed to estimate the cost savings of the integrated approach. All key informant interviews and focus group discussions were semi-structured and flexible. An interview guide that posed broad, open-ended questions was used to guide the conversations without stifling them. Qualitative analysis An inductive thematic analysis, guided by the frameworks of Braun and Clarke 19 and Terry 20 , was used to identify recurrent patterns and develop themes from interview and observational data. This method was chosen because it enables themes to emerge directly from participants’ accounts, making it well suited to exploratory research on evolving surveillance practices. Theme development was iterative, with academic, field team and DoH co-authors jointly reviewing and refining the analysis to ensure it accurately represented shared observations and experiences. Ethics statement The study was approved by the Research Committee of the Niue Department of Health (5 August 2024) and ratified by the UQ Human Research Ethics Committee (approval reference 2024/HE001375; 8 August 2024) and the Alfred Hospital Ethics Committee (approval reference 317/25). Written informed consent was obtained from all participants, with parent or guardian consent for participants aged <18 years. All personal identifiers were removed prior to analysis in accordance with the United States Department of Health and Human Services’ Health Insurance Portability and Accountability Act Privacy Rule. Where applicable, participants provided specific consent for the verbatim reporting of de-identified quotations. The study was conducted in accordance with relevant ethical guidelines and regulations, including the Declaration of Helsinki issued by the World Medical Association and the International Ethical Guidelines for Health-related Research Involving Humans published by the Council for International Organizations of Medical Sciences. Results Lymphatic Filariasis Post-Validation Surveillance Characteristics of participants A total of 898 individuals participated in the survey. Participants from all villages were represented with median coverage across villages of 71.9% (IQR: 59.9-78.1%) and ranging from 28.6% (in Namukulu, a hamlet of ~7 people) to 86.1% (in Hakupu). Coverage in Alofi North and Alofi South (the capital and most populated area) was 74.7% and 56.8%, respectively. 176 participants were aged 3-15 years (~54% of the estimated on-island population in this age group), 628 were aged 15–69 years (~63%), and 47 were >69 years (~35%). A breakdown by age group and village is provided in Table 1. Table 1. Count and age group of participants in the Niue lymphatic filariasis post-validation surveillance survey, 2025. Village Age groups (year olds) Total Est. on-island pop'n Est. percentage surveyed 3-15 15-69 >69 No record Alofi North 27 76 7 2 112 150 74.7% Alofi South 33 134 11 14 192 338 56.8% Avatele 20 46 3 5 74 102 72.5% Hakupu 26 83 4 11 124 144 86.1% Hikutavake 3 20 2 0 25 31 80.6% Lakepa 10 40 4 2 56 76 73.7% Liku 4 36 2 0 42 59 71.2% Makefu 11 33 1 1 46 58 79.3% Mutulau 8 32 3 1 44 62 71.0% Namukulu 0 2 0 0 2 7 28.6% Tamakautoga 10 37 4 1 52 144 36.1% Toi 5 10 1 2 18 26 69.2% Tuapa 16 48 4 2 70 82 85.4% Vaiea 3 30 0 2 35 65 53.8% No record 0 1 1 4 6 Total 176 628 47 47 898 1,344 66.8% Of these, 557 (62.0%) were recruited through STEPS and 341 (38.0%) through community-based collection activities. Of community-based collections, 116 (34.0%) were recruited through the primary school, 84 (24.6%) through the high school, 55 (16.1%) through the hospital, and 72 (22.1%) at other community locations, including the morning market, the bank, and churches. The location of community sampling was not recorded for 14 participants. Antigen and microfilariae testing Of the 898 participants, 845 had blood collected for FTS testing. Of these, 23 did not have sufficient blood to perform FTS, and 14 tests were invalid (10 because the test did not flow, four because the control line did not appear). Insufficient blood was available for retesting. Thus, 808 valid LF FTS tests (95.6% of those provided for FTS testing) were performed. Of the 808 valid tests, only one LF Ag-positive result was detected (0.1% [95% confidence interval: 0.02-0.88] prevalence), and no Mf were observed on thick blood smears (Fig 3). Follow-up testing of household members and those who resided within 100m of the Ag-positive person yielded no further Ag-positive results. This finding suggests that LF Ag prevalence remains well below the WHO threshold of 1% Ag-positive 11 and hence Niue continues to meet the criteria for LF elimination. Antibody testing Ab testing for LF is still an emerging tool and results should be interpreted with a high degree of caution. WHO’s monitoring and epidemiological evaluation guidelines for LF 11 state: “…. exposure to filarial parasites may induce Abs in people, even if a true infection does not occur. Infected people, both microfilaraemic and amicrofilaraemic, have elevated levels of Abs, but the results of Ab testing do not distinguish between current and past infection. Nevertheless, detection of Abs in children demonstrates recent exposure to filarial parasites 11 .” Dried blood spots from 755 participants were prepared and tested using MBA. Five samples were positive for Wb123 Ab, four for Bm14 Ab, and one sample was dual-positive (Fig 3). Ab-positive people were identified in eight of Niue’s 14 administrative areas. Ab-positive individuals ranged from 9 to 66 years old, including two children under 19 years of age, born post-MDA cessation. Three of the Ab-positive people migrants from LF-endemic countries to Niue within the 5 years preceding the survey; one had been in an LF-endemic country for 4 years; and two had epidemiological links to LF-positive people identified during the 2009 survey. A public health investigation is ongoing. Dynamics that support integrated approaches to LF-PVS Field observation data were collected on all collection days, and all senior Niue MoH staff members responsible for implementing the integrated STEPS/LF-PVS surveys were interviewed. This included the lead and deputy lead of the integrated survey, as well as two other senior officers responsible for field implementation, logistics, workflow, and data management. Benefits and enablers of integration Clear operational gains Interviews with Niue DoH staff consistently highlighted that integrating LF-PVS within the STEPS survey generated clear operational gains. Staff reported that shared transport, venue preparation, and data entry processes reduced duplication and improved field efficiency. Core functions, such as community engagement, production of information materials, and consent procedures, were streamlined, strengthening coordination between the two programmes. These efficiencies were particularly valued in Niue, where the health workforce is small and lacks the capacity to implement multiple, similar community-based survey activities simultaneously. National leadership Strong and visible DoH leadership emerged as a central enabler. Both junior and LF-PVS staff recognised the role senior DoH officials played in advocating for trialling the integrated model, and their stewardship throughout planning and implementation were cited as essential to the approach’s success. Beyond the logistical task of aligning two programme workflows, DoH leaders’ willingness to champion integration helped secure staff buy-in, supported rapid problem-solving, and reassured teams that the model was both feasible and aligned with national priorities. Integration with a high-profile and supported programme Through integration, LF-PVS also benefited substantially from being linked to the STEPS survey, a well-known, well-funded, and highly valued NCD initiative. Public interest in NCDs, which represent a major burden of disease in the Pacific, combined with strong promotional efforts by the DoH, helped engage and motivate community members to participate in the survey. LF-PVS, typically attracting less interest, benefited from this momentum; several participants described it as a “low cost” additional activity that made sense to include. Clear points of integration Clear points of integration within the STEPS workflow further supported implementation. Staff emphasised the logical alignment of activities, particularly at blood collection stations, as “making good sense.” Importantly, the LF-PVS team assumed responsibility for glucose and cholesterol testing within the STEPS process, reducing complexity, saving STEPS team labour, and helping all understand where and how LF-PVS added value to the overall workflow. Reduced impost on the public The integrated model also reduced the burden on the public. Community members appreciated contributing to both NCD and infectious disease surveillance during a single visit, avoiding multiple appointments or repeated finger-pricks. The “one prick, many tests” approach was frequently cited as a meaningful benefit, reducing discomfort and reinforcing the sense that the survey respected participants’ time and convenience. This simplicity became a point of discussion within communities and was seen to strengthen trust in the health system. Staff from both the STEPS and LF-PVS study understood the importance of effective, transparent communication. The co-location of both survey programs’ staff at field sites enabled daily joint planning and real-time troubleshooting by mixed teams. The LF-PVS team provided practical support with transport, set-up, and logistics, bringing additional capacity to the STEPS workflow. As one official noted, “integration didn’t mean extra work, it meant more hands to help out.” Cost and labour saving Conceptually clear savings in cost and effort were widely recognised as being a major motivator for senior program leaders’ interest and willingness to trial an integrated model. Staff noted that shared infrastructure and personnel reduced overall requirements. This is consistent with the micro-costing analysis (reported elsewhere 18 ) which showed a 44% reduction in financial costs and nearly 50% labour savings compared with a stand-alone LF-PVS survey. Respondents considered these efficiencies to make an integrated LF-PVS model more realistic and sustainable in the future. Challenges and adaptive practices Despite the overall success, several early challenges were noted. The integrated consent process initially caused confusion for both staff and participants, requiring refinements to wording and workflow. Differences in target age groups between STEPS and LF-PVS also required negotiation. Supplementary community-based data collection activities were added to ensure coverage of individuals (aged 69 years) falling outside the STEPS eligibility criteria. Flexibility was repeatedly identified as essential. Teams adapted daily to weather disruptions, staff availability, community events, and transport issues, often reorganising plans at short notice. The small size of the field team, combined with a positive, pragmatic “can-do” attitude and a highly professional, respected leadership team, supported this agility. Clear communication with the public was reported by interviewees to have contributed to high levels of acceptance and overall, the integrated approach appeared acceptable, well understood, and strongly supported by community members. Discussion We report the findings of the first LF-PVS study conducted in Niue, undertaken nine years after the country was validated as having eliminated the disease as a public health problem. From a near-census survey, only one individual tested Ag-positive, corresponding to a population Ag prevalence of < 0.2%, indicating that Niue has maintained its elimination status. Although Ab testing for LF remains an emerging tool and is not yet used for programmatic decision-making in areas where W. bancrofti is endemic 11 , the detection of 10 Ab-positive individuals, including three young people born after cessation of MDA, may represent an early signal of recent exposure. These findings warrant further scrutiny and follow up. Periodic Ag/Mf testing of Ab-positive individuals may be justified. This “test and watch” approach is consistent with WHO guidance for post-elimination settings and supports early detection of possible resurgence. Additional investigation is needed to understand potential exposure pathways, both within Niue and through international travel. Taken together, the Ab results reinforce the need for ongoing PVS to ensure that any resurgence is detected promptly and addressed before sustained transmission can be re-established. While Ab markers show promise for detecting early exposure to LF and identifying potential resurgence, key questions remain regarding how best to interpret Ab kinetics across the infection trajectory and defining benchmarks for public health action 21 – 23 . Advancing this evidence is essential to ensure that Ab tools are applied appropriately and that the resulting information aligns with the needs of public health decision-makers. The integration of LF-PVS into the STEPS survey generated substantial cost and operational efficiencies. Shared logistics, streamlined consent and community engagement processes, and coordinated field activities reduced duplication and staff workload. These benefits were particularly important in Niue, where the health workforce is small and any additional tasks carry significant opportunity costs. Embedding supplementary surveillance activities within existing, well-supported survey or health service delivery workflows allowed the health system to broaden its public health monitoring capacity without proportionally increasing operational demands. For Pacific Island settings, where parallel campaigns are often impractical due to workforce constraints and geographic dispersion, these findings indicate that integration represents a pragmatic and sustainable strategy for fulfilling LF-PVS requirements. The benefit of integration would likely extend to other disease programmes with examples available from across the world including from Togo where malaria thick blood smears have been screened for W. bancrofti Mf 24 , in Cambodia where MBA for parasitic diseases were integrated into a national serosurvey of women aged 15–39 years of age 25 , in Sudan, integrated serosurveillance for onchoceriasis, LF, and schistosomiasis 26 , in Samoa LF and scabies surveys were integrated 27 , 28 , and in Tonga where LF-PVS was integrated with clinical service provision 29 . The success of the integrated model in Niue was underpinned by effective DoH leadership. Senior officials actively advocated for the approach, helping to secure support from the STEPS programme and frontline staff. Integration also benefited from being attached to the respected, well-promoted, high-profile STEPS survey, which enjoyed strong community interest and acceptance. These findings highlight that successful integration is not solely a technical exercise; it depends heavily on governance, leadership, and programme reputation. This aligns with broader implementation science evidence that leadership engagement and programme visibility are key determinants of effective system change, particularly in settings where programme success relies on community participation 30 – 32 . In places where leadership is limited or the programme is not well known, development partners can use their credibility to help raise community awareness, understanding, and demand for PVS. We note that Niue’s small population (~ 1,300 residents on the island at any given time) enabled the STEPS survey to be conducted as a census of all people aged 15–69 years, with data collected from every village. Because all communities are located on a single, easily accessible island, it was also relatively straightforward to include additional participants outside the STEPS target age range, resulting in an overall survey coverage of roughly 65% of the eligible population across all villages. In larger or more complex settings, and where the sampling frames of ‘host’ programmes do not align neatly with LF-PVS requirements, integration might be more challenging. In these contexts, achieving strong alignment between programme objectives becomes essential, as does building flexibility in the co-design of participating programmes. International agencies, including WHO, that champion integration as a cost-efficient strategy are well placed to identify, promote and help design cross-programme surveillance models that maximise financial, workforce, and logistical gains. Community members consistently valued the “one prick, many tests” model and the convenience of contributing to multiple surveillance activities during a single encounter. The integrated approach was viewed as respectful of participants’ time and was highly acceptable. Minimising participant burden is especially important in small populations, where repeated surveys risk generating fatigue and reduced participation over time. By reducing inconvenience and adding perceived value, the integrated model helped reinforce trust in the health system, an essential foundation for maintaining long-term surveillance in post-elimination settings. These findings suggest that community acceptability should be a core design consideration when developing integrated PVS models for PICTs. By demonstrating that a Small Island Developing State, such as Niue, can deliver LF-PVS effectively by leveraging an existing survey platform, this study shows that integrated surveillance can be both feasible and resource-efficient. Niue’s experience provides a practical model for other countries seeking to protect population health while advancing global development targets outlined in the Sustainable Development Goals (SDGs). In particular, the ability to implement PVS supports progress towards SDG target 3.3, which aims to end NTDs as a public health problem by 2030. The operational efficiencies and community-centred design observed in this study also align with broader SDG priorities, including universal health coverage (SDG target 3.8) and strengthened national health risk management capacities (SDG 3.d). Conclusion This study provides evidence that Niue has maintained LF elimination nine years after validation of elimination as a public health problem, while also signalling, through low Ab prevalence, the need for ongoing vigilance and repeated PVS. By embedding LF-PVS within a national STEPS NCD risk factor survey, we demonstrate that integrated surveillance is both operationally feasible and efficient, delivering substantial cost and labour savings in a health system with constrained capacity. The experience from Niue underscores that successful integration depends not only on technical design but also on strong health authority leadership, alignment with high-profile, trusted programmes, and a deliberate focus on minimising participant burden through approaches such as “one prick, many tests.” Taken together, these findings suggest that programmatically integrated LF-PVS offers a pragmatic, acceptable, and sustainable pathway for PICTs and other countries seeking to protect hard-won elimination gains while advancing broader goals for health system efficiency, person-centred care, and progress towards achievement of the SDGs. Declarations Declaration of interest All authors declare no competing interests. Funding This work is funded by the Global Institute for Disease Elimination (grant # FADE2024/03), the (Australian) National Centre for Immunisation Research and Surveillance (grant #25_0270), and The University of Queensland Health Research Accelerator Initiative (2021–2028). CLL was supported by an NHMRC Investigator Grant (Grant number: 1193826). Author Contribution Conceptualisation: ATC, HLSL GM, and CLL. Investigation: ATC, HLSL, GM, PT, MN, AM, TM, LJR, and FA. Data curation: ATC, HLSL. Project administration: ATC. Analysis: ATC, HLSL, LJR, and FA. Supervision: CLL. Writing - original draft: ATC. Writing - review and editing: all authors. All authors had access to the raw data. All authors reviewed the final manuscript. ATC had responsibility for the decision to submit for publication. Acknowledgements We acknowledge our funders, the Global Institute for Disease Elimination (FADE2024/03), National Centre for Immunisation Research and Surveillance (25_0270), and UQ Health Research Accelerator (HERA) Initiative (2021–2028). LJR and CLL were supported by an NHMRC Investigator Grants (Grant number: 2017630 and 1193826). Data Availability Communities in Niue are small (some with fewer than 10 inhabitants), and sharing individual-level data could enable the identification of individual participants, violating the conditions of the study’s ethics approval. For requests related to data access, please contact the Niue Department of Health Human Ethics Committee via the Niue Public Health Unit’s focal point ( [email protected] ). References Hofstraat, K. & van Brakel, W.H. Social stigma towards neglected tropical diseases: a systematic review. Int Health 8 Suppl 1, i53-70 (2016). Craig, A.T., et al. Integrating post-validation surveillance of lymphatic filariasis with the WHO STEPwise approach to non-communicable disease risk factor surveillance in Niue, a study protocol. PLoS One 20, e0315625 (2025). Russell, T.L. & Burkot, T.R. A guide to mosquitoes in the Pacific 2023, (Pacific Community, 2023). Ichimori, K. & Graves, P.M. Overview of PacELF—the Pacific Programme for the Elimination of Lymphatic Filariasis. Tropical medicine and health 45, 34 (2017). Lammie, P.J., Cuenco, K.T. & Punkosdy, G.A. The pathogenesis of filarial lymphedema: is it the worm or is it the host? Annals of the New York Academy of Sciences 979, 131-142 (2002). The Global Health Observatory. Lymphatic filariasis (Elephantiasis). Vol. 2025 (WHO, Geneva, 2025). Mathew, C.G., et al. The Health and Economic Burdens of Lymphatic Filariasis Prior to Mass Drug Administration Programs. Clin Infect Dis 70, 2561-2567 (2020). GBD 2019 Diseases and Injuries Collaborators. Global burden of 369 diseases and injuries in 204 countries and territories, 1990-2019: a systematic analysis for the Global Burden of Disease Study 2019. Lancet 396, 1204-1222 (2020). Ottesen, E.A., Hooper, P.J., Bradley, M. & Biswas, G. The Global Programme to Eliminate Lymphatic Filariasis: Health Impact after 8 Years. PLOS Neglected Tropical Diseases 2, e317 (2008). World Health Organization. Ending the neglect to attain the Sustainable Development Goals: a rationale for continued investment in tackling neglected tropical diseases 2021–2030, (WHO, Geneva, Switzerland, 2022). World Health Organization. Monitoring and epidemiological assessment of mass drug administration in the global programme to eliminate lymphatic filariasis: a manual for national elimination programmes, second edition, (WHO, Geneva, Switzerland, 2025). Flanagan, M. & Sioneholo, F. 2022 Niue Census of Population and Housing Report. (Niue Ministry of Finance and Planning, Alofi, Niue, 2022). Simpson, E. Mass Therapy in Filariasis. A Note on Control in Niue Island. (1957). Huppatz, C., Capuano, C., Palmer, K., Kelly, P.M. & Durrheim, D.N. Lessons from the Pacific programme to eliminate lymphatic filariasis: a case study of 5 countries. BMC Infectious Diseases 9, 92 (2009). World Health Organization. Final Report of the Regional Committee. in Regional Committee for the Western Pacific Sixty-Seventh Session, 10-14 October 2016 (ed. WHO) (WHO, Manila, Philippines, 2017). World Health Organization. Monitoring and epidemiological assessment of mass drug administration in the global programme to eliminate lymphatic filariasis: a manual for national elimination programmes, (WHO, Geneva, 2011). Carcelen, A.C., et al. Multiplex bead assays enable integrated serological surveillance and reveal cross-pathogen vulnerabilities in Zambezia Province, Mozambique. Nature Communications 16, 7946 (2025). Craig, A.T., et al. Comparison of an Integrated Versus Stand-Alone Approach to Post-Validation Surveillance for Lymphatic Filariasis in Niue: A Micro-Costing Study, 2025. PLOS NTD Preprint(2025). Braun, V. & Clarke, V. Using thematic analysis in psychology. Qualitative research in psychology 3, 77–101 (2006). Terry, T., Hayfield, N., Clarke, V. & Braun, V. The SAGE Handbook of Qualitative Research in Psychology, (SAGE Publications Ltd, London, 2017). Arnold, B.F., Scobie, H.M., Priest, J.W. & Lammie, P.J. Integrated serologic surveillance of population immunity and disease transmission. Emerging infectious diseases 24, 1188 (2018). Kim, W.L., Anneducharme, C. & Bucher, B.J.-M.P. Development and Implementation of a Surveillance Network System for Emerging Infectious Diseases in the Caribbean (ARICABA). Online journal of public health informatics 3(2011). Cadavid Restrepo, A.M., et al. Potential use of antibodies to provide an earlier indication of lymphatic filariasis resurgence in post-mass drug administration surveillance, American Samoa. medRxiv, 2021.2011. 2029.21267031 (2021). Mathieu, E., Dorkenoo, A., Otogbe, F.K., Budge, P.J. & Sodahlon, Y.K. A laboratory-based surveillance system for Wuchereria bancrofti in Togo: a practical model for resource-poor settings. Am J Trop Med Hyg 84, 988-993 (2011). Priest, J.W., et al. Integration of multiplex bead assays for parasitic diseases into a national, population-based serosurvey of women 15-39 years of age in Cambodia. PLoS neglected tropical diseases 10, e0004699 (2016). Coalson, J.E., et al. Integrated Serosurveillance for Onchocerciasis, Lymphatic Filariasis, and Schistosomiasis in North Darfur, Sudan. Am J Trop Med Hyg 111, 58-68 (2024). Willis, G.A., et al. Scabies prevalence after ivermectin-based mass drug administration for lymphatic filariasis, Samoa 2018–2019. PLOS Neglected Tropical Diseases 17, e0011549 (2023). Lau, C.L., et al. Lymphatic filariasis epidemiology in Samoa in 2018: Geographic clustering and higher antigen prevalence in older age groups. PLOS Neglected Tropical Diseases 14, e0008927 (2020). Lawford, H.L.S., et al. Persistent lymphatic filariasis transmission seven years after validation of elimination as a public health problem: a cross-sectional study in Tonga. The Lancet Regional Health – Western Pacific 57(2025). Mendel, P., Meredith, L.S., Schoenbaum, M., Sherbourne, C.D. & Wells, K.B. Interventions in organizational and community context: a framework for building evidence on dissemination and implementation in health services research. Administration and Policy in Mental Health and Mental Health Services Research 35, 21-37 (2008). Brownson, R.C., Shelton, R.C., Geng, E.H. & Glasgow, R.E. Revisiting concepts of evidence in implementation science. Implementation Science 17, 26 (2022). Braithwaite, J., Churruca, K., Long, J.C., Ellis, L.A. & Herkes, J. When complexity science meets implementation science: a theoretical and empirical analysis of systems change. BMC medicine 16, 63 (2018). Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 12 May, 2026 Reviewers agreed at journal 07 May, 2026 Reviews received at journal 18 Mar, 2026 Reviewers agreed at journal 06 Mar, 2026 Reviewers invited by journal 23 Feb, 2026 Editor assigned by journal 23 Feb, 2026 Editor invited by journal 23 Feb, 2026 Submission checks completed at journal 10 Feb, 2026 First submitted to journal 10 Feb, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Craig","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA60lEQVRIiWNgGAWjYFCCBAjFxsB8AEQzNpCghS2BRC0MDDwGxGnhb09+uoGh5p48H/+abxJvGGxkNxxgfiaBT4vEmWdmNxiOFRu2SbzdJjmHIc14wwE2M7xaGG4kmN1gbEhgbJM4u02ah+Fw4oYDDPi1yN9I/wbSYt8GtA+o5T9QC/s3vFoMbuSAbUls4+9hA2o5ANTCg98WwzNvym4kHEtIbpNgM7acY5BsPPMwT7EFPi1yx9O33fhQk2A7v//wwxtvKuxk+463b7yBTwsYJIAIiQRo1DATVA8D/AeAWohWPQpGwSgYBSMJAACpqEt9J12HpgAAAABJRU5ErkJggg==","orcid":"","institution":"University of Queensland","correspondingAuthor":true,"prefix":"","firstName":"Adam","middleName":"","lastName":"Craig","suffix":""},{"id":596989888,"identity":"6c03446b-196f-4d6f-afd9-012d8b083005","order_by":1,"name":"Harriet Lawford","email":"","orcid":"","institution":"University of Queensland","correspondingAuthor":false,"prefix":"","firstName":"Harriet","middleName":"","lastName":"Lawford","suffix":""},{"id":596989889,"identity":"4a796790-1f77-4b5c-910f-3f28e029b903","order_by":2,"name":"Grizelda Mokoia","email":"","orcid":"","institution":"Department of Health","correspondingAuthor":false,"prefix":"","firstName":"Grizelda","middleName":"","lastName":"Mokoia","suffix":""},{"id":596989890,"identity":"f3e3316c-bc01-40db-8ac7-3e9268519e2c","order_by":3,"name":"Patricia Tatui","email":"","orcid":"","institution":"Department of Health","correspondingAuthor":false,"prefix":"","firstName":"Patricia","middleName":"","lastName":"Tatui","suffix":""},{"id":596989891,"identity":"35971a58-c9c1-402b-8fd3-48ffc2c76d21","order_by":4,"name":"Misiona Nicholas","email":"","orcid":"","institution":"Department of Health","correspondingAuthor":false,"prefix":"","firstName":"Misiona","middleName":"","lastName":"Nicholas","suffix":""},{"id":596989892,"identity":"8739a396-28a3-4824-bdde-e920ddd0a4c2","order_by":5,"name":"Andy Manu","email":"","orcid":"","institution":"Department of Health","correspondingAuthor":false,"prefix":"","firstName":"Andy","middleName":"","lastName":"Manu","suffix":""},{"id":596989893,"identity":"125cf866-b560-43d4-88ef-cd2cd43a6723","order_by":6,"name":"Amanda Murphy","email":"","orcid":"","institution":"James Cook University","correspondingAuthor":false,"prefix":"","firstName":"Amanda","middleName":"","lastName":"Murphy","suffix":""},{"id":596989894,"identity":"99652c9c-6797-48ea-a185-91b87892d022","order_by":7,"name":"Tonia Marquardt","email":"","orcid":"","institution":"National Centre for Immunisation Research \u0026 Surveillance","correspondingAuthor":false,"prefix":"","firstName":"Tonia","middleName":"","lastName":"Marquardt","suffix":""},{"id":596989895,"identity":"5d6196ca-39ec-4ef1-b5e2-b8121ed48c9a","order_by":8,"name":"Leanne Robinson","email":"","orcid":"","institution":"Burnet Institute","correspondingAuthor":false,"prefix":"","firstName":"Leanne","middleName":"","lastName":"Robinson","suffix":""},{"id":596989896,"identity":"c170de66-af32-4164-bdb2-4b583f09e5d5","order_by":9,"name":"Fiona Angrisano","email":"","orcid":"","institution":"Burnet Institute","correspondingAuthor":false,"prefix":"","firstName":"Fiona","middleName":"","lastName":"Angrisano","suffix":""},{"id":596989897,"identity":"146e7511-a992-42b0-a7ac-a72d9f707e65","order_by":10,"name":"Colleen Lau","email":"","orcid":"","institution":"University of Queensland","correspondingAuthor":false,"prefix":"","firstName":"Colleen","middleName":"","lastName":"Lau","suffix":""}],"badges":[],"createdAt":"2026-01-29 02:38:56","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8726246/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8726246/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":104401294,"identity":"69acfb46-c431-48cb-9344-d312862c3716","added_by":"auto","created_at":"2026-03-11 12:12:18","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":136672,"visible":true,"origin":"","legend":"\u003cp\u003eNiue and its villages, and Niue's location in the South Pacific Ocean (insert).\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-8726246/v1/29bf1d01ab93b1cdbdddb52f.png"},{"id":103837731,"identity":"a569d748-d169-48da-b1a0-1c16563c30e6","added_by":"auto","created_at":"2026-03-03 14:18:09","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":189613,"visible":true,"origin":"","legend":"\u003cp\u003eTimeline of significant milestones in lymphatic filariasis surveillance, treatment, and elimination in Niue, 1950-2020.\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-8726246/v1/efcdf8b1c5d02ada695332f9.png"},{"id":103837730,"identity":"b6b24e52-807e-48d1-850d-0bfbb7b3c7c1","added_by":"auto","created_at":"2026-03-03 14:18:09","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":107330,"visible":true,"origin":"","legend":"\u003cp\u003eLymphatic filariasis antigen and antibody testing flow and results.\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-8726246/v1/ddd279b5baf9b9e802c9cf1a.png"},{"id":104407987,"identity":"603fd674-417c-4627-897b-38ddbf961687","added_by":"auto","created_at":"2026-03-11 12:41:14","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1327902,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8726246/v1/1b474934-1d40-496d-b3be-74b28478130a.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Integrated Surveillance for Lymphatic Filariasis and other Infectious Diseases with a Nationwide Non-Communicable Disease STEPwise Survey in the small Pacific Island Nation of Niue, 2025","fulltext":[{"header":"Introduction","content":"\u003cp\u003eLymphatic filariasis (LF) is an infection spread by mosquitoes and caused by three filarial worm species: \u003cem\u003eWuchereria bancrofti\u003c/em\u003e, \u003cem\u003eBrugia malayi\u003c/em\u003e and \u003cem\u003eB. timori\u003c/em\u003e \u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e,\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e. Around 90% of global LF cases are due to \u003cem\u003eW. bancrofti\u003c/em\u003e, which is also the only species present in Pacific Island countries and territories \u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e. Transmission occurs when an infected mosquito bites a person, introducing larvae that travel to the lymphatic vessels. There, the parasites develop into adult worms and, if fertilised, produce large numbers of microfilariae (Mf) that circulate in the blood. Most infections begin with no noticeable symptoms \u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e, though people may experience episodes of acute inflammation such as dermatolymphangioadenitis or filarial lymphangitis [5]. If left untreated, chronic immune responses to the adult worms can lead to bacterial superinfection and long-term lymphatic dysfunction, resulting in conditions such as lymphoedema, elephantiasis and scrotal hydrocele \u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e. LF remains a public health issue in 72 countries \u003csup\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e, and in 2019 it was estimated to account for 1.63\u0026nbsp;million disability-adjusted life-years \u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e,\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eThe 1997 World Health Assembly called for the global elimination of LF as a public health problem, prompting the establishment of the Global Programme to Eliminate Lymphatic Filariasis (GPELF) in 2000 \u003csup\u003e9\u003c/sup\u003e. The programme set a target to achieve global elimination by 2020 through surveillance, Mass Drug Administration (MDA), and Morbidity Management and Disability Prevention (MMDP). Although this goal was not met, momentum has continued. In 2021, the World Health Organization released the updated Roadmap for Neglected Tropical Diseases for 2021\u0026ndash;2030, which sets out the expectation that by 2030 all 72 LF-endemic countries will have stopped MDA and will be conducting either post-validation (PVS) or post-MDA surveillance activities \u003csup\u003e\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eAt the country level, elimination of LF as a public health problem is validated by the World Health Organisation (WHO). Countries that achieve validation are encouraged to implement PVS to ensure early detection of any resurgence. Guidance on PVS design, frequency, and duration has been limited, leading to inconsistent implementation and, in many countries, inactivity following validation of elimination. This gap has, in part, been addressed in the 2025 WHO publication entitled \u003cem\u003eMonitoring and epidemiological assessment of mass drug administration in the global programme to eliminate lymphatic filariasis: a manual for national elimination programmes, 2nd ed\u003c/em\u003e \u003csup\u003e11\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eNiue is a small (261 km\u003csup\u003e2\u003c/sup\u003e) self-governing island in the South Pacific, located approximately 660 km southeast of Samoa and 2,400 km northeast of New Zealand (19\u0026deg;S, 169\u0026deg;W). The island has a population of ~\u0026thinsp;1,600 people (about 1,300 of whom are on the island at any one time, though this fluctuates) (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e) \u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e,\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eLF surveys have been conducted in Niue since 1954. In the 1954 population-wide survey, Mf prevalence was found to be 22.2% \u003csup\u003e13\u003c/sup\u003e. Between 1955 and 2005, eight rounds of MDA were implemented, resulting in a reduction in antigen (Ag)-positive prevalence to 0.5% by 2009 \u003csup\u003e2,14\u003c/sup\u003e (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). In October 2016, Niue was validated by WHO as having eliminated LF as a public health problem \u003csup\u003e\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u003c/sup\u003e and the country officially moved into a post-validation phase. Until the present study, no PVS or community surveillance for LF had been conducted.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIn 2025, an integrated approach to LF-PVS was undertaken, where PVS was embedded into a planned and funded national WHO STEPwise non-communicable disease (NCD) risk factor (STEPS) survey that, in addition to asking NCD-related lifestyle, diet, and behavioural questions, collected finger-prick blood samples from participants to test for blood glucose and blood cholesterol levels \u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eHere, we present the results of the LF-PVS survey and discuss the benefits, enablers, challenges, and adaptive practices required to successfully integrate LF-PVS into a routine national public health program.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eThis study had two aims. First, it sought to conduct the first PVS in Niue nine years after the country was validated as having eliminated LF as a public health problem and thereby assess whether the elimination status had been maintained. Second, it aimed to explore critical operational dynamics that support or hinder integrated approaches to LF-PVS in a Pacific Island setting, with the intention of generating practical guidance for other countries and regions seeking cost- and labour-efficient models for PVS implementation.\u003c/p\u003e\n\u003ch2\u003e\u003cstrong\u003eLymphatic filariasis Post-Validation Surveillance (Aim 1)\u003c/strong\u003e\u003c/h2\u003e\n\u003ch3\u003e\u003cstrong\u003ePre-survey community engagement\u003c/strong\u003e\u003c/h3\u003e\n\u003cp\u003eIn the weeks prior to the survey, the Niue Department of Health (DoH) Public Health Unit undertook community awareness activities, including village talks, radio broadcasts and talk-back sessions, and social media messaging. These activities raised awareness of the STEPS and LF-PVS surveys, explained the procedures, and clarified how the collected data would be used and reported.\u003c/p\u003e\n\u003ch3\u003eParticipant recruitment\u003c/h3\u003e\n\u003cp\u003eThe LF-PVS was conducted as a population census of individuals aged \u0026gt;3 years. To achieve this, two recruitment methods were used.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFirst, LF-PVS was integrated with a planned national population-based WHO STEPS survey. Integration between the LF-PVS and STEPS occurred at multiple points in the workflow, including during pre-survey community engagement, when obtaining informed consent, during the collection of survey-based data, and during the collection of finger-prick blood samples to test for cholesterol, glucose, and LF Ag and antibodies (Ab) to multiple pathogens. The STEPS survey\u0026rsquo;s target population were all people aged 16 to 69 years, and the survey was conducted from 24 February to 4 April 2025. STEPS surveying was conducted in community halls and churches across the 14 villages in Niue. This approach is outlined in a published methods paper \u003csup\u003e2\u003c/sup\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSecond, to expand the age range of PVS participants to include younger (3 to 16 years) and older (\u0026gt; 69 years) participants, convenience community-based sampling was used. Community-based sampling was conducted at the country\u0026rsquo;s only primary and high school, the morning market, the bank waiting area, workplaces, churches, and the outpatient clinic at Niue Foou Hospital.\u003c/p\u003e\n\u003cp\u003eEach participant was allocated a unique QR-coded identifier, which was affixed to all study materials (consent forms, questionnaires, blood collection tubes, Bioline\u003csup\u003eTM\u003c/sup\u003e Filariasis Test Strip (FTS) (Abbott, Scarborough, ME), slides, and dried blood spots (DBS) [see below] to support linkage and tracking.\u003c/p\u003e\n\u003ch3\u003eField logistics, demographic, and travel history data collection\u003c/h3\u003e\n\u003cp\u003eAt each STEPS survey site, participants moved through three \u0026lsquo;stations.\u0026rsquo; First, at a dedicated \u0026lsquo;registration and consent station,\u0026rsquo; participants provided demographic information (age, sex, country of birth, village of residence, occupation) and gave written consent to participate in both the STEPS and/or LF-PVS studies (participants could opt in/out of either study). Second, participants proceeded to \u0026lsquo;blood collection stations,\u0026rsquo; where at least 300\u0026mu;L of finger-prick blood was collected into heparin-coated BD Microtainers\u0026reg; Blood Collection Tubes and stored in a cooler box for later LF testing and DBS preparation (as part of LF-PVS) at a field laboratory. Third, participants attended an \u0026lsquo;interview station\u0026rsquo; where questions on international travel history were embedded in the standard STEPS questionnaire to collect data on participants\u0026rsquo; travel to LF-endemic countries. Data were captured in a standardized from developed by WHO and collected through a purpose-built ODK platform\u003c/p\u003e\n\u003cp\u003eFor samples collected through community-based sampling, consent, blood collection, and LF-related risk questions were completed at a single station.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eEpiCollect5 software (v76.1.0; https://five.epicollect.net/) was used to collect and to link STEPS and community sampling data.\u003c/p\u003e\n\u003ch3\u003eLymphatic filariasis laboratory testing\u003c/h3\u003e\n\u003cp\u003eFor each participant, blood samples were tested for LF Ag using FTS. For any Ag-positive samples, Mf slides were prepared using methods described previously \u003csup\u003e16\u003c/sup\u003e and read independently by two trained microscopists in Australia. Household members and those residing within 100m of any Ag-positive person were followed up and, if not already done, LF Ag testing was offered.\u003c/p\u003e\n\u003cp\u003eFor all participants, DBS were collected onto\u0026nbsp;Cellabs Tropbio Filter Paper Blood Collection Disks\u0026trade;\u0026nbsp;(up to 6 x 10 \u0026mu;L spots) for multiplex bead assay (MBA) analysis using Luminex\u0026reg; technology to detect Ab for a panel of infectious diseases, including two Abs for LF (\u003cem\u003eWb123\u003c/em\u003e and \u003cem\u003eBm14\u003c/em\u003e) \u003csup\u003e17\u003c/sup\u003e.\u003c/p\u003e\n\u003ch3\u003eStatistical analysis\u003c/h3\u003e\n\u003cp\u003eData were analysed using Stata (Version 19.0; StataCorp, College Station, TX). Descriptive statistics were generated for Ag and Ab results, and 95% confidence intervals were computed for relevant demographic variables, including age, sex, and village of residence.\u003c/p\u003e\n\u003ch2\u003eDynamics that support integrated approaches to LF-PVS (Aim 2)\u003c/h2\u003e\n\u003ch3\u003eData collection\u003c/h3\u003e\n\u003cp\u003eThree sources of data related to the dynamics that supported integrated PVS were collected. First, field observations of the LF-PVS team were collected through daily and end-of-survey debriefing sessions. Second, key informant interviews were conducted with purposefully selected Niue DoH staff directly involved in implementing the integrated STEPS/LF-PVS approach. And third, a micro-costing analysis (which has been published elsewhere \u003csup\u003e18\u003c/sup\u003e) was performed to estimate the cost savings of the integrated approach.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAll key informant interviews and focus group discussions were semi-structured and flexible. An interview guide that posed broad, open-ended questions was used to guide the conversations without stifling them.\u003c/p\u003e\n\u003ch3\u003eQualitative analysis\u003c/h3\u003e\n\u003cp\u003eAn inductive thematic analysis, guided by the frameworks of Braun and Clarke \u003csup\u003e19\u003c/sup\u003e and Terry \u003csup\u003e20\u003c/sup\u003e, was used to identify recurrent patterns and develop themes from interview and observational data. This method was chosen because it enables themes to emerge directly from participants\u0026rsquo; accounts, making it well suited to exploratory research on evolving surveillance practices. Theme development was iterative, with academic, field team and DoH co-authors jointly reviewing and refining the analysis to ensure it accurately represented shared observations and experiences.\u003c/p\u003e\n\u003ch2\u003e\u003cstrong\u003eEthics statement\u003c/strong\u003e\u003c/h2\u003e\n\u003cp\u003eThe study was approved by the Research Committee of the Niue Department of Health (5 August 2024) and ratified by the UQ Human Research Ethics Committee (approval reference 2024/HE001375; 8 August 2024) and the Alfred Hospital Ethics Committee (approval reference 317/25). Written informed consent was obtained from all participants, with parent or guardian consent for participants aged \u0026lt;18 years. All personal identifiers were removed prior to analysis in accordance with the United States Department of Health and Human Services\u0026rsquo; Health Insurance Portability and Accountability Act Privacy Rule. Where applicable, participants provided specific consent for the verbatim reporting of de-identified quotations. The study was conducted in accordance with relevant ethical guidelines and regulations, including the Declaration of Helsinki issued by the World Medical Association and the International Ethical Guidelines for Health-related Research Involving Humans published by the Council for International Organizations of Medical Sciences.\u003c/p\u003e"},{"header":"Results","content":"\u003ch2\u003e\u003cstrong\u003eLymphatic Filariasis Post-Validation Surveillance\u003c/strong\u003e\u003c/h2\u003e\n\u003ch3\u003eCharacteristics of participants\u003c/h3\u003e\n\u003cp\u003eA total of 898 individuals participated in the survey. Participants from all villages were represented with median coverage across villages of 71.9% (IQR: 59.9-78.1%) and ranging from 28.6% (in Namukulu, a hamlet of ~7 people) to 86.1% (in Hakupu). Coverage in Alofi North and Alofi South (the capital and most populated area) was 74.7% and 56.8%, respectively. 176 participants were aged 3-15 years (~54% of the estimated on-island population in this age group), 628 were aged 15\u0026ndash;69 years (~63%), and 47 were \u0026gt;69 years (~35%). A breakdown by age group and village is provided in Table 1.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 1. Count and age group of participants in the Niue lymphatic filariasis post-validation surveillance survey, 2025.\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"599\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 113px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eVillage\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"4\" valign=\"top\" style=\"width: 264px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAge groups (year olds)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 48px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTotal\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 84px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEst. on-island pop\u0026apos;n\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEst. percentage surveyed\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 73px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e3-15\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 54px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e15-69\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 40px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026gt;69\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 97px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo record\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eAlofi North\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 73px;\"\u003e\n \u003cp\u003e27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 40px;\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 97px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e112\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e150\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e74.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eAlofi South\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 73px;\"\u003e\n \u003cp\u003e33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e134\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 40px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 97px;\"\u003e\n \u003cp\u003e14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e192\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e338\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e56.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eAvatele\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 73px;\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 40px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 97px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e102\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e72.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eHakupu\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 73px;\"\u003e\n \u003cp\u003e26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 40px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 97px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e124\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e144\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e86.1%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eHikutavake\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 73px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 40px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 97px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e80.6%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eLakepa\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 73px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 40px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 97px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e73.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eLiku\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 73px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 40px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 97px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e71.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eMakefu\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 73px;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 40px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 97px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e58\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e79.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eMutulau\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 73px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 40px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 97px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e44\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e71.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eNamukulu\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 73px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 40px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 97px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e28.6%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eTamakautoga\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 73px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 40px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 97px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e144\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e36.1%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eToi\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 73px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 40px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 97px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e69.2%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eTuapa\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 73px;\"\u003e\n \u003cp\u003e16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e48\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 40px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 97px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e85.4%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eVaiea\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 73px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 40px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 97px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e65\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e53.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003eNo record\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 73px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 40px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 97px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 113px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTotal\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 73px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e176\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e628\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 40px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e47\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 97px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e47\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e898\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 84px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e1,344\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e66.8%\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eOf these, 557 (62.0%) were recruited through STEPS and 341 (38.0%) through community-based collection activities. Of community-based collections, 116 (34.0%) were recruited through the primary school, 84 (24.6%) through the high school, 55 (16.1%) through the hospital, and 72 (22.1%) at other community locations, including the morning market, the bank, and churches. The location of community sampling was not recorded for 14 participants.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eAntigen and microfilariae testing\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eOf the 898 participants, 845 had blood collected for FTS testing. Of these, 23 did not have sufficient blood to perform FTS, and 14 tests were invalid (10 because the test did not flow, four because the control line did not appear). Insufficient blood was available for retesting. Thus, 808 valid LF FTS tests (95.6% of those provided for FTS testing) were performed.\u003c/p\u003e\n\u003cp\u003eOf the 808 valid tests, only one LF Ag-positive result was detected (0.1% [95% confidence interval: 0.02-0.88] prevalence), and no Mf were observed on thick blood smears (Fig 3). Follow-up testing of household members and those who resided within 100m of the Ag-positive person yielded no further Ag-positive results. This finding suggests that LF Ag prevalence remains well below the WHO threshold of 1% Ag-positive \u003csup\u003e11\u003c/sup\u003e and hence Niue continues to meet the criteria for LF elimination.\u003c/p\u003e\n\u003ch3\u003eAntibody testing\u003c/h3\u003e\n\u003cp\u003eAb testing for LF is still an emerging tool and results should be interpreted with a high degree of caution. WHO\u0026rsquo;s monitoring and epidemiological evaluation guidelines for LF \u003csup\u003e11\u003c/sup\u003e state:\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u0026ldquo;\u0026hellip;. exposure to filarial parasites may induce Abs in people, even if a true infection does not occur. Infected people, both microfilaraemic and amicrofilaraemic, have elevated levels of Abs, but the results of Ab testing do not distinguish between current and past infection. Nevertheless, detection of Abs in children demonstrates recent exposure to filarial parasites\u0026nbsp;\u003c/em\u003e\u003cem\u003e\u003csup\u003e11\u003c/sup\u003e\u003c/em\u003e\u003cem\u003e.\u0026rdquo;\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eDried blood spots from 755 participants were prepared and tested using MBA. Five samples were positive for \u003cem\u003eWb123\u003c/em\u003e Ab, four for \u003cem\u003eBm14\u003c/em\u003e Ab, and one sample was dual-positive (Fig 3). Ab-positive people were identified in eight of Niue\u0026rsquo;s 14 administrative areas. Ab-positive individuals ranged from 9 to 66 years old, including two children under 19 years of age, born post-MDA cessation. Three of the Ab-positive people migrants from LF-endemic countries to Niue within the 5 years preceding the survey; one had been in an LF-endemic country for 4 years; and two had epidemiological links to LF-positive people identified during the 2009 survey. A public health investigation is ongoing.\u003c/p\u003e\n\u003ch2\u003eDynamics that support integrated approaches to LF-PVS\u003c/h2\u003e\n\u003cp\u003eField observation data were collected on all collection days, and all senior Niue MoH staff members responsible for implementing the integrated STEPS/LF-PVS surveys were interviewed. This included the lead and deputy lead of the integrated survey, as well as two other senior officers responsible for field implementation, logistics, workflow, and data management.\u003c/p\u003e\n\u003ch3\u003eBenefits and enablers of integration\u003c/h3\u003e\n\u003ch4\u003eClear operational gains\u003c/h4\u003e\n\u003cp\u003eInterviews with Niue DoH staff consistently highlighted that integrating LF-PVS within the STEPS survey generated clear operational gains. Staff reported that shared transport, venue preparation, and data entry processes reduced duplication and improved field efficiency. Core functions, such as community engagement, production of information materials, and consent procedures, were streamlined, strengthening coordination between the two programmes. These efficiencies were particularly valued in Niue, where the health workforce is small and lacks the capacity to implement multiple, similar community-based survey activities simultaneously.\u003c/p\u003e\n\u003ch4\u003eNational leadership\u003c/h4\u003e\n\u003cp\u003eStrong and visible DoH leadership emerged as a central enabler. Both junior and LF-PVS staff recognised the role senior DoH officials played in advocating for trialling the integrated model, and their stewardship throughout planning and implementation were cited as essential to the approach\u0026rsquo;s success. Beyond the logistical task of aligning two programme workflows, DoH leaders\u0026rsquo; willingness to champion integration helped secure staff buy-in, supported rapid problem-solving, and reassured teams that the model was both feasible and aligned with national priorities.\u003c/p\u003e\n\u003ch4\u003eIntegration with a high-profile and supported programme\u003c/h4\u003e\n\u003cp\u003eThrough integration, LF-PVS also benefited substantially from being linked to the STEPS survey, a well-known, well-funded, and highly valued NCD initiative. Public interest in NCDs, which represent a major burden of disease in the Pacific, combined with strong promotional efforts by the DoH, helped engage and motivate community members to participate in the survey. LF-PVS, typically attracting less interest, benefited from this momentum; several participants described it as a \u0026ldquo;low cost\u0026rdquo; additional activity that made sense to include.\u003c/p\u003e\n\u003ch4\u003eClear points of integration\u003c/h4\u003e\n\u003cp\u003eClear points of integration within the STEPS workflow further supported implementation. Staff emphasised the logical alignment of activities, particularly at blood collection stations, as \u0026ldquo;making good sense.\u0026rdquo; Importantly, the LF-PVS team assumed responsibility for glucose and cholesterol testing within the STEPS process, reducing complexity, saving STEPS team labour, and helping all understand where and how LF-PVS added value to the overall workflow.\u003c/p\u003e\n\u003ch4\u003eReduced impost on the public\u003c/h4\u003e\n\u003cp\u003eThe integrated model also reduced the burden on the public. Community members appreciated contributing to both NCD and infectious disease surveillance during a single visit, avoiding multiple appointments or repeated finger-pricks. The \u0026ldquo;one prick, many tests\u0026rdquo; approach was frequently cited as a meaningful benefit, reducing discomfort and reinforcing the sense that the survey respected participants\u0026rsquo; time and convenience. This simplicity became a point of discussion within communities and was seen to strengthen trust in the health system.\u003c/p\u003e\n\u003cp\u003eStaff from both the STEPS and LF-PVS study understood the importance of effective, transparent communication. The co-location of both survey programs\u0026rsquo; staff at field sites enabled daily joint planning and real-time troubleshooting by mixed teams. The LF-PVS team provided practical support with transport, set-up, and logistics, bringing additional capacity to the STEPS workflow. As one official noted, \u0026ldquo;integration didn\u0026rsquo;t mean extra work, it meant more hands to help out.\u0026rdquo;\u003c/p\u003e\n\u003ch4\u003eCost and labour saving\u003c/h4\u003e\n\u003cp\u003eConceptually clear savings in cost and effort were widely recognised as being a major motivator for senior program leaders\u0026rsquo; interest and willingness to trial an integrated model. Staff noted that shared infrastructure and personnel reduced overall requirements. This is consistent with the micro-costing analysis (reported elsewhere \u003csup\u003e18\u003c/sup\u003e) which showed a 44% reduction in financial costs and nearly 50% labour savings compared with a stand-alone LF-PVS survey. Respondents considered these efficiencies to make an integrated LF-PVS model more realistic and sustainable in the future.\u003c/p\u003e\n\u003ch3\u003eChallenges and adaptive practices\u003c/h3\u003e\n\u003cp\u003eDespite the overall success, several early challenges were noted. The integrated consent process initially caused confusion for both staff and participants, requiring refinements to wording and workflow. Differences in target age groups between STEPS and LF-PVS also required negotiation. Supplementary community-based data collection activities were added to ensure coverage of individuals (aged \u0026lt;16 and \u0026gt;69 years) falling outside the STEPS eligibility criteria.\u003c/p\u003e\n\u003cp\u003eFlexibility was repeatedly identified as essential. Teams adapted daily to weather disruptions, staff availability, community events, and transport issues, often reorganising plans at short notice. The small size of the field team, combined with a positive, pragmatic \u0026ldquo;can-do\u0026rdquo; attitude and a highly professional, respected leadership team, supported this agility. Clear communication with the public was reported by interviewees to have contributed to high levels of acceptance and overall, the integrated approach appeared acceptable, well understood, and strongly supported by community members.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eWe report the findings of the first LF-PVS study conducted in Niue, undertaken nine years after the country was validated as having eliminated the disease as a public health problem. From a near-census survey, only one individual tested Ag-positive, corresponding to a population Ag prevalence of \u0026lt;\u0026thinsp;0.2%, indicating that Niue has maintained its elimination status.\u003c/p\u003e \u003cp\u003eAlthough Ab testing for LF remains an emerging tool and is not yet used for programmatic decision-making in areas where \u003cem\u003eW. bancrofti\u003c/em\u003e is endemic \u003csup\u003e\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e, the detection of 10 Ab-positive individuals, including three young people born after cessation of MDA, may represent an early signal of recent exposure. These findings warrant further scrutiny and follow up. Periodic Ag/Mf testing of Ab-positive individuals may be justified. This \u0026ldquo;test and watch\u0026rdquo; approach is consistent with WHO guidance for post-elimination settings and supports early detection of possible resurgence. Additional investigation is needed to understand potential exposure pathways, both within Niue and through international travel. Taken together, the Ab results reinforce the need for ongoing PVS to ensure that any resurgence is detected promptly and addressed before sustained transmission can be re-established.\u003c/p\u003e \u003cp\u003eWhile Ab markers show promise for detecting early exposure to LF and identifying potential resurgence, key questions remain regarding how best to interpret Ab kinetics across the infection trajectory and defining benchmarks for public health action \u003csup\u003e\u003cspan additionalcitationids=\"CR22\" citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u003c/sup\u003e. Advancing this evidence is essential to ensure that Ab tools are applied appropriately and that the resulting information aligns with the needs of public health decision-makers.\u003c/p\u003e \u003cp\u003eThe integration of LF-PVS into the STEPS survey generated substantial cost and operational efficiencies. Shared logistics, streamlined consent and community engagement processes, and coordinated field activities reduced duplication and staff workload. These benefits were particularly important in Niue, where the health workforce is small and any additional tasks carry significant opportunity costs. Embedding supplementary surveillance activities within existing, well-supported survey or health service delivery workflows allowed the health system to broaden its public health monitoring capacity without proportionally increasing operational demands. For Pacific Island settings, where parallel campaigns are often impractical due to workforce constraints and geographic dispersion, these findings indicate that integration represents a pragmatic and sustainable strategy for fulfilling LF-PVS requirements. The benefit of integration would likely extend to other disease programmes with examples available from across the world including from Togo where malaria thick blood smears have been screened for \u003cem\u003eW. bancrofti\u003c/em\u003e Mf \u003csup\u003e24\u003c/sup\u003e, in Cambodia where MBA for parasitic diseases were integrated into a national serosurvey of women aged 15\u0026ndash;39 years of age \u003csup\u003e\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u003c/sup\u003e, in Sudan, integrated serosurveillance for onchoceriasis, LF, and schistosomiasis \u003csup\u003e\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u003c/sup\u003e, in Samoa LF and scabies surveys were integrated \u003csup\u003e\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e,\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e\u003c/sup\u003e, and in Tonga where LF-PVS was integrated with clinical service provision \u003csup\u003e\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eThe success of the integrated model in Niue was underpinned by effective DoH leadership. Senior officials actively advocated for the approach, helping to secure support from the STEPS programme and frontline staff. Integration also benefited from being attached to the respected, well-promoted, high-profile STEPS survey, which enjoyed strong community interest and acceptance. These findings highlight that successful integration is not solely a technical exercise; it depends heavily on governance, leadership, and programme reputation. This aligns with broader implementation science evidence that leadership engagement and programme visibility are key determinants of effective system change, particularly in settings where programme success relies on community participation \u003csup\u003e\u003cspan additionalcitationids=\"CR31\" citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e\u003c/sup\u003e. In places where leadership is limited or the programme is not well known, development partners can use their credibility to help raise community awareness, understanding, and demand for PVS.\u003c/p\u003e \u003cp\u003eWe note that Niue\u0026rsquo;s small population (~\u0026thinsp;1,300 residents on the island at any given time) enabled the STEPS survey to be conducted as a census of all people aged 15\u0026ndash;69 years, with data collected from every village. Because all communities are located on a single, easily accessible island, it was also relatively straightforward to include additional participants outside the STEPS target age range, resulting in an overall survey coverage of roughly 65% of the eligible population across all villages. In larger or more complex settings, and where the sampling frames of \u0026lsquo;host\u0026rsquo; programmes do not align neatly with LF-PVS requirements, integration might be more challenging. In these contexts, achieving strong alignment between programme objectives becomes essential, as does building flexibility in the co-design of participating programmes. International agencies, including WHO, that champion integration as a cost-efficient strategy are well placed to identify, promote and help design cross-programme surveillance models that maximise financial, workforce, and logistical gains.\u003c/p\u003e \u003cp\u003eCommunity members consistently valued the \u0026ldquo;one prick, many tests\u0026rdquo; model and the convenience of contributing to multiple surveillance activities during a single encounter. The integrated approach was viewed as respectful of participants\u0026rsquo; time and was highly acceptable. Minimising participant burden is especially important in small populations, where repeated surveys risk generating fatigue and reduced participation over time. By reducing inconvenience and adding perceived value, the integrated model helped reinforce trust in the health system, an essential foundation for maintaining long-term surveillance in post-elimination settings. These findings suggest that community acceptability should be a core design consideration when developing integrated PVS models for PICTs.\u003c/p\u003e \u003cp\u003eBy demonstrating that a Small Island Developing State, such as Niue, can deliver LF-PVS effectively by leveraging an existing survey platform, this study shows that integrated surveillance can be both feasible and resource-efficient. Niue\u0026rsquo;s experience provides a practical model for other countries seeking to protect population health while advancing global development targets outlined in the Sustainable Development Goals (SDGs). In particular, the ability to implement PVS supports progress towards SDG target 3.3, which aims to end NTDs as a public health problem by 2030. The operational efficiencies and community-centred design observed in this study also align with broader SDG priorities, including universal health coverage (SDG target 3.8) and strengthened national health risk management capacities (SDG 3.d).\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study provides evidence that Niue has maintained LF elimination nine years after validation of elimination as a public health problem, while also signalling, through low Ab prevalence, the need for ongoing vigilance and repeated PVS. By embedding LF-PVS within a national STEPS NCD risk factor survey, we demonstrate that integrated surveillance is both operationally feasible and efficient, delivering substantial cost and labour savings in a health system with constrained capacity. The experience from Niue underscores that successful integration depends not only on technical design but also on strong health authority leadership, alignment with high-profile, trusted programmes, and a deliberate focus on minimising participant burden through approaches such as \u0026ldquo;one prick, many tests.\u0026rdquo; Taken together, these findings suggest that programmatically integrated LF-PVS offers a pragmatic, acceptable, and sustainable pathway for PICTs and other countries seeking to protect hard-won elimination gains while advancing broader goals for health system efficiency, person-centred care, and progress towards achievement of the SDGs.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003ch2\u003eDeclaration of interest\u003c/h2\u003e \u003cp\u003eAll authors declare no competing interests.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e \u003cp\u003eThis work is funded by the Global Institute for Disease Elimination (grant # FADE2024/03), the (Australian) National Centre for Immunisation Research and Surveillance (grant #25_0270), and The University of Queensland Health Research Accelerator Initiative (2021\u0026ndash;2028). CLL was supported by an NHMRC Investigator Grant (Grant number: 1193826).\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eConceptualisation: ATC, HLSL GM, and CLL. Investigation: ATC, HLSL, GM, PT, MN, AM, TM, LJR, and FA. Data curation: ATC, HLSL. Project administration: ATC. Analysis: ATC, HLSL, LJR, and FA. Supervision: CLL. Writing - original draft: ATC. Writing - review and editing: all authors. All authors had access to the raw data. All authors reviewed the final manuscript. ATC had responsibility for the decision to submit for publication.\u003c/p\u003e\u003ch2\u003eAcknowledgements\u003c/h2\u003e \u003cp\u003eWe acknowledge our funders, the Global Institute for Disease Elimination (FADE2024/03), National Centre for Immunisation Research and Surveillance (25_0270), and UQ Health Research Accelerator (HERA) Initiative (2021\u0026ndash;2028). LJR and CLL were supported by an NHMRC Investigator Grants (Grant number: 2017630 and 1193826).\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eCommunities in Niue are small (some with fewer than 10 inhabitants), and sharing individual-level data could enable the identification of individual participants, violating the conditions of the study\u0026rsquo;s ethics approval. For requests related to data access, please contact the Niue Department of Health Human Ethics Committee via the Niue Public Health Unit\u0026rsquo;s focal point ([email protected] ).\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eHofstraat, K. \u0026amp; van Brakel, W.H. Social stigma towards neglected tropical diseases: a systematic review. Int Health 8 Suppl 1, i53-70 (2016).\u003c/li\u003e\n\u003cli\u003eCraig, A.T., et al. Integrating post-validation surveillance of lymphatic filariasis with the WHO STEPwise approach to non-communicable disease risk factor surveillance in Niue, a study protocol. PLoS One 20, e0315625 (2025).\u003c/li\u003e\n\u003cli\u003eRussell, T.L. \u0026amp; Burkot, T.R. A guide to mosquitoes in the Pacific 2023, (Pacific Community, 2023).\u003c/li\u003e\n\u003cli\u003eIchimori, K. \u0026amp; Graves, P.M. Overview of PacELF\u0026mdash;the Pacific Programme for the Elimination of Lymphatic Filariasis. Tropical medicine and health 45, 34 (2017).\u003c/li\u003e\n\u003cli\u003eLammie, P.J., Cuenco, K.T. \u0026amp; Punkosdy, G.A. The pathogenesis of filarial lymphedema: is it the worm or is it the host? Annals of the New York Academy of Sciences 979, 131-142 (2002).\u003c/li\u003e\n\u003cli\u003eThe Global Health Observatory. Lymphatic filariasis (Elephantiasis). Vol. 2025 (WHO, Geneva, 2025).\u003c/li\u003e\n\u003cli\u003eMathew, C.G., et al. The Health and Economic Burdens of Lymphatic Filariasis Prior to Mass Drug Administration Programs. Clin Infect Dis 70, 2561-2567 (2020).\u003c/li\u003e\n\u003cli\u003eGBD 2019 Diseases and Injuries Collaborators. Global burden of 369 diseases and injuries in 204 countries and territories, 1990-2019: a systematic analysis for the Global Burden of Disease Study 2019. Lancet 396, 1204-1222 (2020).\u003c/li\u003e\n\u003cli\u003eOttesen, E.A., Hooper, P.J., Bradley, M. \u0026amp; Biswas, G. The Global Programme to Eliminate Lymphatic Filariasis: Health Impact after 8 Years. PLOS Neglected Tropical Diseases 2, e317 (2008).\u003c/li\u003e\n\u003cli\u003eWorld Health Organization. Ending the neglect to attain the Sustainable Development Goals: a rationale for continued investment in tackling neglected tropical diseases 2021\u0026ndash;2030, (WHO, Geneva, Switzerland, 2022).\u003c/li\u003e\n\u003cli\u003eWorld Health Organization. Monitoring and epidemiological assessment of mass drug administration in the global programme to eliminate lymphatic filariasis: a manual for national elimination programmes, second edition, (WHO, Geneva, Switzerland, 2025).\u003c/li\u003e\n\u003cli\u003eFlanagan, M. \u0026amp; Sioneholo, F. 2022 Niue Census of Population and Housing Report. (Niue Ministry of Finance and Planning, Alofi, Niue, 2022).\u003c/li\u003e\n\u003cli\u003eSimpson, E. Mass Therapy in Filariasis. A Note on Control in Niue Island. (1957).\u003c/li\u003e\n\u003cli\u003eHuppatz, C., Capuano, C., Palmer, K., Kelly, P.M. \u0026amp; Durrheim, D.N. Lessons from the Pacific programme to eliminate lymphatic filariasis: a case study of 5 countries. BMC Infectious Diseases 9, 92 (2009).\u003c/li\u003e\n\u003cli\u003eWorld Health Organization. Final Report of the Regional Committee. in Regional Committee for the Western Pacific Sixty-Seventh Session, 10-14 October 2016 (ed. WHO) (WHO, Manila, Philippines, 2017).\u003c/li\u003e\n\u003cli\u003eWorld Health Organization. Monitoring and epidemiological assessment of mass drug administration in the global programme to eliminate lymphatic filariasis: a manual for national elimination programmes, (WHO, Geneva, 2011).\u003c/li\u003e\n\u003cli\u003eCarcelen, A.C., et al. Multiplex bead assays enable integrated serological surveillance and reveal cross-pathogen vulnerabilities in Zambezia Province, Mozambique. Nature Communications 16, 7946 (2025).\u003c/li\u003e\n\u003cli\u003eCraig, A.T., et al. Comparison of an Integrated Versus Stand-Alone Approach to Post-Validation Surveillance for Lymphatic Filariasis in Niue: A Micro-Costing Study, 2025. PLOS NTD Preprint(2025).\u003c/li\u003e\n\u003cli\u003eBraun, V. \u0026amp; Clarke, V. Using thematic analysis in psychology. Qualitative research in psychology 3, 77\u0026ndash;101 (2006).\u003c/li\u003e\n\u003cli\u003eTerry, T., Hayfield, N., Clarke, V. \u0026amp; Braun, V. The SAGE Handbook of Qualitative Research in Psychology, (SAGE Publications Ltd, London, 2017).\u003c/li\u003e\n\u003cli\u003eArnold, B.F., Scobie, H.M., Priest, J.W. \u0026amp; Lammie, P.J. Integrated serologic surveillance of population immunity and disease transmission. Emerging infectious diseases 24, 1188 (2018).\u003c/li\u003e\n\u003cli\u003eKim, W.L., Anneducharme, C. \u0026amp; Bucher, B.J.-M.P. Development and Implementation of a Surveillance Network System for Emerging Infectious Diseases in the Caribbean (ARICABA). Online journal of public health informatics 3(2011).\u003c/li\u003e\n\u003cli\u003eCadavid Restrepo, A.M., et al. Potential use of antibodies to provide an earlier indication of lymphatic filariasis resurgence in post-mass drug administration surveillance, American Samoa. medRxiv, 2021.2011. 2029.21267031 (2021).\u003c/li\u003e\n\u003cli\u003eMathieu, E., Dorkenoo, A., Otogbe, F.K., Budge, P.J. \u0026amp; Sodahlon, Y.K. A laboratory-based surveillance system for Wuchereria bancrofti in Togo: a practical model for resource-poor settings. Am J Trop Med Hyg 84, 988-993 (2011).\u003c/li\u003e\n\u003cli\u003ePriest, J.W., et al. Integration of multiplex bead assays for parasitic diseases into a national, population-based serosurvey of women 15-39 years of age in Cambodia. PLoS neglected tropical diseases 10, e0004699 (2016).\u003c/li\u003e\n\u003cli\u003eCoalson, J.E., et al. Integrated Serosurveillance for Onchocerciasis, Lymphatic Filariasis, and Schistosomiasis in North Darfur, Sudan. Am J Trop Med Hyg 111, 58-68 (2024).\u003c/li\u003e\n\u003cli\u003eWillis, G.A., et al. Scabies prevalence after ivermectin-based mass drug administration for lymphatic filariasis, Samoa 2018\u0026ndash;2019. PLOS Neglected Tropical Diseases 17, e0011549 (2023).\u003c/li\u003e\n\u003cli\u003eLau, C.L., et al. Lymphatic filariasis epidemiology in Samoa in 2018: Geographic clustering and higher antigen prevalence in older age groups. PLOS Neglected Tropical Diseases 14, e0008927 (2020).\u003c/li\u003e\n\u003cli\u003eLawford, H.L.S., et al. Persistent lymphatic filariasis transmission seven years after validation of elimination as a public health problem: a cross-sectional study in Tonga. The Lancet Regional Health \u0026ndash; Western Pacific 57(2025).\u003c/li\u003e\n\u003cli\u003eMendel, P., Meredith, L.S., Schoenbaum, M., Sherbourne, C.D. \u0026amp; Wells, K.B. Interventions in organizational and community context: a framework for building evidence on dissemination and implementation in health services research. Administration and Policy in Mental Health and Mental Health Services Research 35, 21-37 (2008).\u003c/li\u003e\n\u003cli\u003eBrownson, R.C., Shelton, R.C., Geng, E.H. \u0026amp; Glasgow, R.E. Revisiting concepts of evidence in implementation science. Implementation Science 17, 26 (2022).\u003c/li\u003e\n\u003cli\u003eBraithwaite, J., Churruca, K., Long, J.C., Ellis, L.A. \u0026amp; Herkes, J. When complexity science meets implementation science: a theoretical and empirical analysis of systems change. BMC medicine 16, 63 (2018).\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Pacific Islands, neglected diseases, epidemiology, public health surveillance","lastPublishedDoi":"10.21203/rs.3.rs-8726246/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8726246/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe small Pacific island nation of Niue was validated by the WHO in 2016 as having eliminated lymphatic filariasis (LF) as a public health problem; however, no post-validation surveillance (PVS) has been conducted since. In 2025, LF-PVS was integrated into a near-census national WHO STEPwise non-communicable disease (NCD) risk factor survey, a cost-effective approach for estimating LF prevalence and assessing whether elimination had been sustained. Finger-prick blood samples were tested for LF antigen and antibodies; antigen-positive samples were screened for microfilariae. One participant was antigen-positive (0.1%, 95% CI 0.02\u0026ndash;0.88), and no microfilariae were detected, indicating sustained elimination. Ten participants were antibody-positive (five \u003cem\u003eWb123\u003c/em\u003e, four \u003cem\u003eBm14\u003c/em\u003e, one dual-positive). Semi-structured interviews provided operational insights, indicating that integrating LF-PVS into the programme was resource-efficient, logistically feasible, and acceptable to both health workers and the community. This study is the first to demonstrate integrated NCD\u0026ndash;communicable disease surveillance in the Pacific.\u003c/p\u003e","manuscriptTitle":"Integrated Surveillance for Lymphatic Filariasis and other Infectious Diseases with a Nationwide Non-Communicable Disease STEPwise Survey in the small Pacific Island Nation of Niue, 2025","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-03 14:18:04","doi":"10.21203/rs.3.rs-8726246/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"38343108161195452170408006358454408053","date":"2026-05-12T13:52:30+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"182749962977157816928979265923130839962","date":"2026-05-07T16:42:28+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-03-18T12:09:58+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"49953566607906366927842129901606369604","date":"2026-03-06T14:36:07+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-02-23T13:51:33+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-02-23T13:48:22+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-02-23T10:50:49+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-02-10T07:28:38+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2026-02-10T07:10:52+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"ce96dcd8-7d80-4d10-9324-be2ca9de18da","owner":[],"postedDate":"March 3rd, 2026","published":true,"recentEditorialEvents":[{"type":"reviewerAgreed","content":"38343108161195452170408006358454408053","date":"2026-05-12T13:52:30+00:00","index":45,"fulltext":""},{"type":"reviewerAgreed","content":"182749962977157816928979265923130839962","date":"2026-05-07T16:42:28+00:00","index":44,"fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[{"id":63525592,"name":"Health sciences/Diseases"},{"id":63525593,"name":"Health sciences/Health care"},{"id":63525594,"name":"Biological sciences/Immunology"},{"id":63525595,"name":"Health sciences/Medical research"},{"id":63525596,"name":"Biological sciences/Microbiology"}],"tags":[],"updatedAt":"2026-03-03T14:18:04+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-03 14:18:04","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8726246","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8726246","identity":"rs-8726246","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}