Modelling the effect of vaccination on transmission dynamics of nervous necrosis virus in grouper larvae Epinephelus coioides

27 Jul 2020
Lu TH, Chen CY, Yang YF and Liao CM

Abstract

Nervous necrosis virus (NNV) infection in susceptible grouper larvae has been reported to cause high mortalities, leading to great economic losses in aquaculture industry. Although the effects of NNV vaccines on grouper have been broadly investigated, vaccination strategies have not been fully established. To this end, we introduced the parsimonious epidemiological models that explored the assessment of key epidemiological parameters and how they changed when vaccinations showed the effects. We showed that the models capture the published cumulative mortality data accurately. We estimated a basic reproduction number R0 = 2.44 for NNV transmission in grouper larvae without vaccination. To effectively control NNV transmission by vaccination, a model for disease control was also generalized to attain the goals of controlled reproduction number less than 1. Our results indicated that at least 60% of grouper population needed to be immunized for ~75 min. Our data‐driven modelling approach that links the transmission dynamics of NNV and vaccination strategies for grouper has the potential to support evidence‐based planning and adaptation of integrated control measures. We encourage that the epidemiology‐based framework introduced here can be further implemented for establishing effective vaccination and mitigation actions aimed at controlling diseases in fish farming practices.