Background: Malaria hosts are known to manipulate the feeding behaviour of mosquitoes to protect them from external threats and control. In particular, the phenomenon in which a mosquito's feeding target is biased toward an infectious host is called a vector-bias, and it can be a threat to malaria eradication if not considered. Aim of the study is to understand the problems that may arise when vector-bias is not considered in early invasion scenarios.
Methods: Stochastic formulations of malaria transmission, including the vector-bias effect, ware constructed. Invasive dynamics were investigated using an individual-based continuous time Markov chain model and the offspring distributions of secondary infections. In addition, the extinction probability was derived using the negative binomial count model.
Results: Invasions will occur quickly, and once the disease spreads, extinction will become difficult compared to when the vector-bias effect is not considered. In a highly heterogeneous environment, vector-bias has rare effect on decreasing the extinction probability.
Conclusion: The early detection of a malaria invasion and the early control beginning are more important due to vector-bias for the malaria eradication in early invasion scenarios. In addition, some possible mosquito-biased behaviours were discussed in terms of adaptive dynamics.