Dynamics of a climate-based periodic Chikungunya model with incubation period

In order to study the effect of temperature on the mosquito population dynamics, we propose a Chikungunya transmission model with time-varying parameters and time-dependent extrinsic incubation period (EIP). The model includes the larval and mature stages of mosquitoes. We deduce the vector reproduction number R-v and the basic reproduction number R-0, and then show that these two threshold values completely determine the global dynamics of the model system. More precisely, (i) if R-v < 1. then mosquito population will become extinct ultimately; (ii) if R-v > 1 and R-0 < 1, then Chikungunya disease will be eliminated; (iii) if R-v > 1 and R-0 > 1. then the disease will persist and fluctuate periodically. Numerically, we explore the spread of Chikungunya disease in Delhi, India. The analytic results are in good consistence with our numerical simulations. Further, an interesting finding is that if the time-averaged EIP is used, then R-0 may be underestimated, and the number of infectious humans and mosquitoes may be underestimated or overestimated. (C) 2019 Elsevier Inc. All rights reserved.