Invasive pneumococcal disease in a Level 4 teaching hospital in Dublin in period 2012 – 2023

Invasive pneumococcal disease in a Level 4 teaching hospital in Dublin in period 2012 – 2023 | 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 Research Article Invasive pneumococcal disease in a Level 4 teaching hospital in Dublin in period 2012 – 2023 Sean Walsh, Gabriela Dornikova, Aoife Hehir, Dylan Shannon, Catherine Taaffe, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7479925/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Streptococcus pneumoniae is a major pathogen, causing invasive infection in children and adults. The current study retrospectively evaluated IPD in adults in a level 4 teaching hospital in 12-year period. Data on invasive SPN was extracted from Microbiology laboratory system and clinical data from the Patient Centre Information System. All patient data were anonymised at the time of collection. Total number of IPD cases in studied period was 210. Mean age of the patients was 57.9 years, and male: female ratio 1.7. All-cause mortality at 12 months was 50 (23.8%). The susceptibility and serotypes of the organism were assessed. An associated cost of the disease was calculated, and it showed that 7 034 556 € was the total inpatient cost of the disease. Our data showed, that IPD is a severe disease with significant morbidity, mortality and associated cost. Financial calculation showed significant amount of money, considering the fact, that the disease is vaccine preventable. Irish data suggests, that vaccine uptake in adults is suboptimal nationally, ranging between 27% and 36%. There is a need to increase vaccine uptake in adults. General Microbiology Bacteriology Infectious Diseases Epidemiology Invasive pneumococcal disease pneumococcal vaccination risk factors pneumococcal vaccine uptake in adults Figures Figure 1 Introduction Streptococcus pneumoniae is a major pathogen causing community-acquired pneumonia, meningitis, sepsis, otitis media, less frequently osteomyelitis, endocarditis and intra-abdominal infection [ 1 ]. Continued surveillance of invasive pneumococcal disease (IPD), including monitoring of invasive S. pneumoniae serotypes, and the sensitivity patterns of the organism are important for vaccination and treatment strategies [ 2 ]. IPD is a vaccine preventable disease. In Ireland 7- and 13-valent pneumococcal conjugate vaccines (PCV7 and PCV13) were introduced into the Irish paediatrics immunization schedule in 2008 and 2010 [ 3 ]. The uptake of the three doses of PCV13 at 24 months of age is ranging between 90–92% [ 4 ]. A 23-valent polysaccharide vaccine (PPV23), introduced in 1983, is recommended for adults ≥ 65, and for high-risk adults < 65 years with immunosuppressive conditions or co-morbidities. PPV23 uptake in adults in Ireland is low (27–36%) [ 4 ]. The current study evaluated incidence of IPD in adults at Mater Misericordiae University Hospital (MMUH) in 12-year period, from 1st January 2012 throughout to 31st December 2023. Data on clinical presentation, risk factors and clinical outcome was collected, and susceptibility to antibiotics and serotypes were assessed. In addition, an associated cost of the disease was calculated. Methods This retrospective cohort study was conducted at MMUH, using data on invasive pneumococcal disease, i.e. clinically significant cases with bacteraemia due to S. pneumoniae. The study was granted the MMUH Research Ethics Committee approval 1/378/2468. MMUH is a level 4 teaching hospital and a tertiary referral centre for cardiothoracic surgery, the national centre for heart and lung transplant, as well as the national centre for numerous diseases and procedures in cardiology, spinal surgery, haematology, oncology, and genetics. Data was extracted from Microbiology laboratory system and the Patient Centre system. Serotyping of the isolates was provided by The Irish Meningitis and Sepsis Reference Laboratory. All patient data were anonymised at the time of collection. Electronic data were password-protected and kept on MMUH network computers. Results Total number of IPD cases in studied period 2012–2023 was 210. Mean age of the patients was 57.9 years, and male: female ratio 132: 78. Proportion of the patients older than 65 years was 40.9%. All-cause mortality at 12 months was 23.8%. Clinical presentation was mostly due to pneumonia (n = 190; 90.5%), 11 (5.2%) cases were clinically meningitis, 1 (0.5%) patient presented with Austrian syndrome (triad of pneumonia, meningitis and infective endocarditis), and 7 (3.3%) had another source. In 2 (1.0%) cases the source of bacteraemia was not clarified. The most frequent underlying conditions were smoking cigarettes in 79 (37.6%) cases, presence of a chronic lung disease in 57 (27.1%), malignancy in 42 (20.0%), chronic liver disease and alcohol excess in 32 (15.2%) each. Further conditions included HIV positive status, diabetes mellitus, intravenous drug use, substances use, chronic renal disease, sarcoidosis and asplenia. Number of IPD cases varied during the studied period 2012–2023, ranging between 8 and 27 annually. Further breakdown showed that median annual rate was 17.5 cases per year and the median incidence was 0.73 per 1 000 hospital admissions. This is illustrated in Fig. 1 . Antimicrobial susceptibility was assessed, following The European Committee on Antimicrobial Susceptibility Testing (EUCAST) Guidelines [ 5 ]. Total of 25 (11.9%) penicillin non-wild-type (PEN non-WT) isolates were identified, of those 21 (10.0%) were intermediate and 4 (1.9%) resistant to penicillin. 5 (2.4%) isolates were intermediate to ceftriaxone and cefotaxime, 21 (10.0%) isolates resistant to erythromycin, 1 (0.5%) resistant to moxifloxacin, and 0 (0.0%) resistant to vancomycin. Combined antimicrobial resistance PEN non-WT plus resistance to erythromycin occurred in 17 (8.1%) cases. Analysis of serotypes showed that the most prevalent in our patient cohort was serotype 8 (n = 35; 16.7%), followed by serotypes 4 (n = 19; 9.0%) and 3 (n = 14; 6.7%). Serotype 8 is contained in vaccine PPV 23, serotype 4 in PCV7 and serotype 3 in PCV13. Proportion of non-vaccine serotypes was low. An associated cost of the disease was calculated, using the hospital information on estimated cost of the acute in-patient hospital beds. €7 034 556 was the total inpatient cost of the disease in our hospital in studied period 2012–2023. Annually, the cost was ranging between €196 798 (in 2020) and €1 455 012 (in 2023). An annual mean was €586 213. One IPD case cost mean was €33 498. Discussion Our data showed, that IPD is a severe disease with significant morbidity, mortality and associated cost. In our cohort of 210 cases, pneumonia was the most frequent presentation (90.5%). All-cause mortality at 12 months was 23.8%. An associated inpatient cost of the disease was €7 034 556 in period 2012–2023. Annually, the cost was ranging between €196 798 and €1 455 012. An annual mean was €586 213. A recent paper (Brown, 2024) analysed economic impact of IPD among older adults in France, using mathematical modelling. Based on the national incidence of IPD, on annual incidence of inpatient and outpatient visits, and on the direct cost of inpatients and outpatients, they reported €97 842 453 as the costs of pneumococcal disease for age group 65+ [ 6 ]. In our study, only inpatient cost was calculated. Swedish data (Zarabi, 2023) showed, that the 30-day total direct cost of pneumococcal disease between 2015 and 2019 was €54 000 000, with 95% of costs from hospitalizations. The clinical and economic burden of pneumococcal disease in adults was found to increase with age, with nearly all costs associated with pneumococcal disease from hospitalizations. The 30-day case fatality rate was highest in the oldest age group, though not negligible in the younger age groups [ 7 ]. Irish data suggests, that vaccine uptake in adults is suboptimal nationally, ranging between 27% and 36% [ 4 ]. There is a need to increase vaccine uptake in adults, that would significantly decrease the cost associated with IPD treatment. Implementation of a new conjugate vaccine PCV20, approved in Ireland since February 2022, can be beneficial, too. There is evidence on better immunological response of conjugate vaccine in comparison with polysaccharide vaccine [ 8 ]. Moreover, PCV20 can replace 2-step vaccination schedule in those, who are immunocompromised. In conclusion, our data showed, that IPD is a severe disease with significant morbidity, mortality and associated cost. There is an urgent need to increase vaccination uptake in adults. Limitations of the study are based on its retrospective character. A potential source of bias would be the patients, who had no blood culture taken due to atypical presentation. Declarations Funding: No funding was granted to this study. Conflicts of interest: The authors report there are no competing interests to declare. Ethics Committee approval number: 1/378/2468. Data availability : Data are available upon reasonable request to corresponding author. References Health Protection Surveillance Centre Invasive Pneumococcal Disease in Ireland – Report from 2019–2021; April 2022 Health Protection Surveillance Centre (2024) Streptococcus pneumoniae (invasive) in Ireland, 2023. HSE HPSC, Dublin Corcoran M, Mereckiene J, Cotter S et al (2020) Invasive Streptococcus pneumoniae Infections and Vaccine Failures in Children in Ireland from the Post-vaccine Era From 2007 to 2018. Pediatr Infect Dis J. Apr; 39(4): 339–344. 10.1097/INF.0000000000002549 . PMID: 31815827 Corcoran M, Vickers I, Mereckiene J et al (2017) The epidemiology of invasive pneumococcal disease in older adults in the post-PCV era. Has there been a herd effect? Epidemiol Infect 145(11):2390–2399 PMID: 28712384; PMCID: PMC9148822 The European Committee on Antimicrobial Susceptibility Testing. Breakpoint tables for interpretation of MICs and zone diameters. Version 13.0 (2023) http://www.eucast.org Brown L, Sutton KJ, Browne C et al (2024) Cost of illness of the vaccine-preventable diseases influenza, herpes zoster and pneumococcal disease in France. Eur J Public Health 34(1):170–175. 10.1093/eurpub/ckad212 PMID: 38061039; PMCID: PMC10843936 Zarabi N, Aldvén M, Sjölander S et al (2023) Clinical and economic burden of pneumococcal disease among adults in Sweden: A population-based register study. PLoS ONE 18(7):e0287581. 10.1371/journal.pone.0287581 PMID: 37418396; PMCID: PMC10328229 Micoli F, Romano MR, Carboni F et al (2023) Strengths and weaknesses of pneumococcal conjugate vaccines. Glycoconj J 40(2):135–148. 10.1007/s10719-023-10100-3 Epub 2023 Jan 18. PMID: 36652051; PMCID: PMC10027807 Additional Declarations The authors declare no competing interests. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7479925","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":506930411,"identity":"f69a0bcc-2edd-4b5e-9ced-0407e5f223d7","order_by":0,"name":"Sean Walsh","email":"","orcid":"","institution":"Mater Misericordiae University Hospital, Dublin","correspondingAuthor":false,"prefix":"","firstName":"Sean","middleName":"","lastName":"Walsh","suffix":""},{"id":506930412,"identity":"d8dabee3-94c0-48cc-bdc3-07ff4158fc01","order_by":1,"name":"Gabriela 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2023\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7479925/v1/d7992c5b9657f170165d7d81.png"},{"id":90320431,"identity":"da10f838-12ed-447c-bb03-0e3570e82111","added_by":"auto","created_at":"2025-09-01 10:44:51","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":293790,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7479925/v1/5400d1f3-f8d7-4176-bb0c-047e5134fd5e.pdf"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003e\u003cstrong\u003eInvasive pneumococcal disease in a Level 4 teaching hospital in Dublin in period 2012 – 2023\u003c/strong\u003e\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003e\u003cem\u003eStreptococcus pneumoniae\u003c/em\u003e is a major pathogen causing community-acquired pneumonia, meningitis, sepsis, otitis media, less frequently osteomyelitis, endocarditis and intra-abdominal infection [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eContinued surveillance of invasive pneumococcal disease (IPD), including monitoring of invasive \u003cem\u003eS. pneumoniae\u003c/em\u003e serotypes, and the sensitivity patterns of the organism are important for vaccination and treatment strategies [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eIPD is a vaccine preventable disease. In Ireland 7- and 13-valent pneumococcal conjugate vaccines (PCV7 and PCV13) were introduced into the Irish paediatrics immunization schedule in 2008 and 2010 [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. The uptake of the three doses of PCV13 at 24 months of age is ranging between 90\u0026ndash;92% [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eA 23-valent polysaccharide vaccine (PPV23), introduced in 1983, is recommended for adults\u0026thinsp;\u0026ge;\u0026thinsp;65, and for high-risk adults\u0026thinsp;\u0026lt;\u0026thinsp;65 years with immunosuppressive conditions or co-morbidities. PPV23 uptake in adults in Ireland is low (27\u0026ndash;36%) [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe current study evaluated incidence of IPD in adults at Mater Misericordiae University Hospital (MMUH) in 12-year period, from 1st January 2012 throughout to 31st December 2023. Data on clinical presentation, risk factors and clinical outcome was collected, and susceptibility to antibiotics and serotypes were assessed. In addition, an associated cost of the disease was calculated.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eThis retrospective cohort study was conducted at MMUH, using data on invasive pneumococcal disease, i.e. clinically significant cases with bacteraemia due to S. pneumoniae. The study was granted the MMUH Research Ethics Committee approval 1/378/2468.\u003c/p\u003e\u003cp\u003eMMUH is a level 4 teaching hospital and a tertiary referral centre for cardiothoracic surgery, the national centre for heart and lung transplant, as well as the national centre for numerous diseases and procedures in cardiology, spinal surgery, haematology, oncology, and genetics.\u003c/p\u003e\u003cp\u003eData was extracted from Microbiology laboratory system and the Patient Centre system. Serotyping of the isolates was provided by The Irish Meningitis and Sepsis Reference Laboratory. All patient data were anonymised at the time of collection. Electronic data were password-protected and kept on MMUH network computers.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eTotal number of IPD cases in studied period 2012\u0026ndash;2023 was 210. Mean age of the patients was 57.9 years, and male: female ratio 132: 78. Proportion of the patients older than 65 years was 40.9%. All-cause mortality at 12 months was 23.8%. Clinical presentation was mostly due to pneumonia (n\u0026thinsp;=\u0026thinsp;190; 90.5%), 11 (5.2%) cases were clinically meningitis, 1 (0.5%) patient presented with Austrian syndrome (triad of pneumonia, meningitis and infective endocarditis), and 7 (3.3%) had another source. In 2 (1.0%) cases the source of bacteraemia was not clarified.\u003c/p\u003e\u003cp\u003eThe most frequent underlying conditions were smoking cigarettes in 79 (37.6%) cases, presence of a chronic lung disease in 57 (27.1%), malignancy in 42 (20.0%), chronic liver disease and alcohol excess in 32 (15.2%) each. Further conditions included HIV positive status, diabetes mellitus, intravenous drug use, substances use, chronic renal disease, sarcoidosis and asplenia.\u003c/p\u003e\u003cp\u003eNumber of IPD cases varied during the studied period 2012\u0026ndash;2023, ranging between 8 and 27 annually. Further breakdown showed that median annual rate was 17.5 cases per year and the median incidence was 0.73 per 1 000 hospital admissions. This is illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eAntimicrobial susceptibility was assessed, following The European Committee on Antimicrobial Susceptibility Testing (EUCAST) Guidelines [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Total of 25 (11.9%) penicillin non-wild-type (PEN non-WT) isolates were identified, of those 21 (10.0%) were intermediate and 4 (1.9%) resistant to penicillin. 5 (2.4%) isolates were intermediate to ceftriaxone and cefotaxime, 21 (10.0%) isolates resistant to erythromycin, 1 (0.5%) resistant to moxifloxacin, and 0 (0.0%) resistant to vancomycin. Combined antimicrobial resistance PEN non-WT plus resistance to erythromycin occurred in 17 (8.1%) cases.\u003c/p\u003e\u003cp\u003eAnalysis of serotypes showed that the most prevalent in our patient cohort was serotype 8 (n\u0026thinsp;=\u0026thinsp;35; 16.7%), followed by serotypes 4 (n\u0026thinsp;=\u0026thinsp;19; 9.0%) and 3 (n\u0026thinsp;=\u0026thinsp;14; 6.7%). Serotype 8 is contained in vaccine PPV 23, serotype 4 in PCV7 and serotype 3 in PCV13. Proportion of non-vaccine serotypes was low.\u003c/p\u003e\u003cp\u003eAn associated cost of the disease was calculated, using the hospital information on estimated cost of the acute in-patient hospital beds. \u0026euro;7 034 556 was the total inpatient cost of the disease in our hospital in studied period 2012\u0026ndash;2023. Annually, the cost was ranging between \u0026euro;196 798 (in 2020) and \u0026euro;1 455 012 (in 2023). An annual mean was \u0026euro;586 213. One IPD case cost mean was \u0026euro;33 498.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eOur data showed, that IPD is a severe disease with significant morbidity, mortality and associated cost. In our cohort of 210 cases, pneumonia was the most frequent presentation (90.5%). All-cause mortality at 12 months was 23.8%.\u003c/p\u003e\u003cp\u003eAn associated inpatient cost of the disease was \u0026euro;7 034 556 in period 2012\u0026ndash;2023. Annually, the cost was ranging between \u0026euro;196 798 and \u0026euro;1 455 012. An annual mean was \u0026euro;586 213.\u003c/p\u003e\u003cp\u003eA recent paper (Brown, 2024) analysed economic impact of IPD among older adults in France, using mathematical modelling. Based on the national incidence of IPD, on annual incidence of inpatient and outpatient visits, and on the direct cost of inpatients and outpatients, they reported \u0026euro;97 842 453 as the costs of pneumococcal disease for age group 65+ [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. In our study, only inpatient cost was calculated.\u003c/p\u003e\u003cp\u003eSwedish data (Zarabi, 2023) showed, that the 30-day total direct cost of pneumococcal disease between 2015 and 2019 was \u0026euro;54 000 000, with 95% of costs from hospitalizations. The clinical and economic burden of pneumococcal disease in adults was found to increase with age, with nearly all costs associated with pneumococcal disease from hospitalizations. The 30-day case fatality rate was highest in the oldest age group, though not negligible in the younger age groups [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eIrish data suggests, that vaccine uptake in adults is suboptimal nationally, ranging between 27% and 36% [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. There is a need to increase vaccine uptake in adults, that would significantly decrease the cost associated with IPD treatment. Implementation of a new conjugate vaccine PCV20, approved in Ireland since February 2022, can be beneficial, too. There is evidence on better immunological response of conjugate vaccine in comparison with polysaccharide vaccine [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Moreover, PCV20 can replace 2-step vaccination schedule in those, who are immunocompromised.\u003c/p\u003e\u003cp\u003eIn conclusion, our data showed, that IPD is a severe disease with significant morbidity, mortality and associated cost. There is an urgent need to increase vaccination uptake in adults.\u003c/p\u003e\u003cp\u003eLimitations of the study are based on its retrospective character. A potential source of bias would be the patients, who had no blood culture taken due to atypical presentation.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding:\u0026nbsp;\u003c/strong\u003eNo funding was granted to this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts of interest:\u0026nbsp;\u003c/strong\u003eThe authors report there are no competing interests to declare.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics Committee\u0026nbsp;\u003c/strong\u003eapproval number: 1/378/2468.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e: Data are available upon reasonable request to corresponding author.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eHealth Protection Surveillance Centre Invasive Pneumococcal Disease in Ireland \u0026ndash; Report from 2019\u0026ndash;2021; April 2022\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHealth Protection Surveillance Centre (2024) Streptococcus pneumoniae (invasive) in Ireland, 2023. HSE HPSC, Dublin\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eCorcoran M, Mereckiene J, Cotter S et al (2020) Invasive Streptococcus pneumoniae Infections and Vaccine Failures in Children in Ireland from the Post-vaccine Era From 2007 to 2018. Pediatr Infect Dis J. Apr; 39(4): 339\u0026ndash;344. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1097/INF.0000000000002549\u003c/span\u003e\u003cspan address=\"10.1097/INF.0000000000002549\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. PMID: 31815827\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eCorcoran M, Vickers I, Mereckiene J et al (2017) The epidemiology of invasive pneumococcal disease in older adults in the post-PCV era. Has there been a herd effect? Epidemiol Infect 145(11):2390\u0026ndash;2399 PMID: 28712384; PMCID: PMC9148822\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eThe European Committee on Antimicrobial Susceptibility Testing. Breakpoint tables for interpretation of MICs and zone diameters. Version 13.0 (2023) \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://www.eucast.org\u003c/span\u003e\u003cspan address=\"http://www.eucast.org\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBrown L, Sutton KJ, Browne C et al (2024) Cost of illness of the vaccine-preventable diseases influenza, herpes zoster and pneumococcal disease in France. Eur J Public Health 34(1):170\u0026ndash;175. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1093/eurpub/ckad212\u003c/span\u003e\u003cspan address=\"10.1093/eurpub/ckad212\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003ePMID: 38061039; PMCID: PMC10843936\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eZarabi N, Aldv\u0026eacute;n M, Sj\u0026ouml;lander S et al (2023) Clinical and economic burden of pneumococcal disease among adults in Sweden: A population-based register study. PLoS ONE 18(7):e0287581. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1371/journal.pone.0287581\u003c/span\u003e\u003cspan address=\"10.1371/journal.pone.0287581\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003ePMID: 37418396; PMCID: PMC10328229\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMicoli F, Romano MR, Carboni F et al (2023) Strengths and weaknesses of pneumococcal conjugate vaccines. Glycoconj J 40(2):135\u0026ndash;148. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s10719-023-10100-3\u003c/span\u003e\u003cspan address=\"10.1007/s10719-023-10100-3\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003eEpub 2023 Jan 18. PMID: 36652051; PMCID: PMC10027807\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"Mater Misericordiae University Hospital, Dublin","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Invasive pneumococcal disease, pneumococcal vaccination, risk factors, pneumococcal vaccine uptake in adults","lastPublishedDoi":"10.21203/rs.3.rs-7479925/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7479925/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eStreptococcus pneumoniae is a major pathogen, causing invasive infection in children and adults. The current study retrospectively evaluated IPD in adults in a level 4 teaching hospital in 12-year period.\u003c/p\u003e\n\u003cp\u003eData on invasive SPN was extracted from Microbiology laboratory system and clinical data from the Patient Centre Information System. All patient data were anonymised at the time of collection.\u003c/p\u003e\n\u003cp\u003eTotal number of IPD cases in studied period was 210. Mean age of the patients was 57.9 years, and male: female ratio 1.7. All-cause mortality at 12 months was 50 (23.8%). The susceptibility and serotypes of the organism were assessed. An associated cost of the disease was calculated, and it showed that 7 034 556 € was the total inpatient cost of the disease.\u003c/p\u003e\n\u003cp\u003eOur data showed, that IPD is a severe disease with significant morbidity, mortality and associated cost. Financial calculation showed significant amount of money, considering the fact, that the disease is vaccine preventable. Irish data suggests, that vaccine uptake in adults is suboptimal nationally, ranging between 27% and 36%. There is a need to increase vaccine uptake in adults.\u003c/p\u003e","manuscriptTitle":"Invasive pneumococcal disease in a Level 4 teaching hospital in Dublin in period 2012 – 2023","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-09-01 10:44:42","doi":"10.21203/rs.3.rs-7479925/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"114acca7-cc39-47b8-b333-f49d380752f2","owner":[],"postedDate":"September 1st, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":53847751,"name":"General Microbiology"},{"id":53847752,"name":"Bacteriology"},{"id":53847753,"name":"Infectious Diseases"},{"id":53847754,"name":"Epidemiology"}],"tags":[],"updatedAt":"2025-09-01T10:44:42+00:00","versionOfRecord":[],"versionCreatedAt":"2025-09-01 10:44:42","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7479925","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7479925","identity":"rs-7479925","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}