Oral rabies vaccine baiting and targeted removal strategies for dog-mediated rabies outbreak control: a modelling framework for outbreak management

Background Support for ongoing regional rabies elimination efforts in dogs and reducing cross border transmission is vital to prevent outbreaks in areas that have previously achieved elimination. However, there are limited studies to estimate their potential use as preventive measures. We explore the effectiveness of two control interventions, oral rabies vaccination (ORV) and targeted ring removal (TRR).

A spatio-temporal compartmental microsimulation model of 2200 free-roaming dogs (FRDs) was fitted to surveillance data with one-time, once-per-year and once-per-month rabies importation events modelled. Based on estimated dog biting rates, seven intervention strategies of TRR and ORV were explored to assess transmission risk reduction in 10,000 model runs.

In the absence of intervention, median human infections over 50 months were 0 (IQR: 0–8), 1 (0–11) and 16 (5–29) for one-time, once-per-year, and once-per-month importation events, with 23.5%, 63.1%, and 99.97% of simulations estimating at least one human case. For one-time and annual importation, 50% dog population TRR reduced this to 6.9% and 29.6%, and 90% ORV coverage down further to 5.0% and 23.5%. Under monthly importation, both TRR and ORV did not substantially reduce the number of simulations without infection but did reduce the number of infections down to 4 (0–12) and 3 (0–8).

ORV can be successfully utilised for dog-mediated rabies outbreak control in elimination settings but at higher importation rates, may only reduce outbreak size. High TRR rates are required for an equivalent impact which may not be feasible. Additional strong border surveillance and vaccine stockpiling is recommended for outbreak risk mitigation. Competing Interest Statement The authors have declared no competing interest. Funding Statement This work was supported by the National Parks Board Fund [WBS A-8001402-00-00]; PREPARE Ministry of Health [WBS A-8000642-01-00]. Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Data Availability All data produced in the present study are available upon reasonable request to the authors