Anthropogenic impact on the vector capacity of Culex pipiens

The mosquito species Culex pipiens has two biotypes pipiens and molestus that are identical morphologically but differ genetically and behaviourally. One important behavioural difference is their host preference - pipiens is ornithophilic and molestus is anthropophilic. Due to increased temperatures because of human activity, these two biotypes are forming hybrids that are capable of feeding on both humans and birds, which allows them to act as bridge vectors for zoonotic diseases like the West Nile Virus (WNV). Seasonal transmission of the WNV has been linked to the change in host feeding from birds to humans by the Culex mosquitoes, but little is known about the genetic processes governing this change in host preference. Olfaction in mosquitoes plays a large part in guiding host seeking behaviour in mosquitoes as distinguishing between the odours of the host species help dictate how the mosquitoes will behave. Therefore, by studying the genes responsible for olfaction we can understand what determines host preference in the two Culex biotypes.

My goal for this project will be to characterise the host preference phenotypes of the two biotypes and their hybrids and to determine whether there are associated genotypes underlying this vector-related behaviour. Using behavioural and molecular approaches in the laboratory, and population surveys in the field, I will provide a mechanistic description to the host preference behaviour to create a model to predict whether hybrid mosquitoes are able to transmit diseases more readily.

Doctoral Researcher: Rohan Menon (SLU)

Supervision: Dr Sharon Rose Hill (SLU), Dr Rickard Ignell (SLU), and Dr Martin Andersson (LU)