A periodic Chikungunya model with virus mutation and transovarial transmission.

In this paper, a Chikungunya dynamical model with virus mutation and transovarial transmission is developed, which incorporates the effect of seasonal temperature changes on disease transmission through time-dependent parameters. Firstly, the threshold parameter R 0 m that determines the persistence and extinction of mosquito populations is given, and then the disease reproduction number R 0 is defined. Secondly, it is proved that if R 0 m > 1 and R 0 < 1, the disease disappears; if R 0 m > 1 and R 0 > 1, then Chikungunya with mutants and non-mutants will persist simultaneously. Finally, a case study is carried out with the data in Kerala, India, where the virus mutation causes the outbreak of Chikungunya. Data on newly confirmed human cases in the state between 2007 and 2010 is fitted and the theoretical results obtained in the previous section are validated. In addition, the effects of seasonal temperature change, virus mutation and transovarial transmission on the prevalence of the disease are studied by numerical simulations from different aspects. 2020 MSC: 34K13; 37N25; 92D30. • A Chikungunya model with virus mutation and transovarial transmission is developed. • The effect of seasonal temperature changes is incorporated. • If there is no seasonality, R 0 will be overestimated. • If there is no virus mutation, the infected population will be underestimated. • When R 0 is less than and close to 1, increasing of transovarial transmission rate will lead to disease outbreak. [ABSTRACT FROM AUTHOR]