Impact of Mutation on the Invasion Potential of Chikungunya Outbreak

Chikungunya is an arthritogenic alphavirus responsible for chikungunya fever that is transmitted by Aedes aegypty and Aedes albopictus. As an RNA virus, a single mutation is introduced with a new variant ECSA-V, which has a shorter extrinsic incubation period (EIP). The SEIR model of chikungunya transmission is delineated, that explained the reduction of basic reproduction number (R_0) due to the mutation. The purpose of this work is to investigate the impact of mutation on the disease outbreak. Numerical simulation of the mathematical model has illustrated the realizations of the stochastic simulation of the estimation of invasion potential and revealed the distribution of mutant and non-mutant individual applying the Direct Method of Gillespie Algorithm. For R_0 near 1, the impact of the mutation on the invasion potential is examined. Also, the aptness of the mosquitoes for invasion potential is established mathematically.