Preparedness against emerging mosquito-borne viral threats

Vector-borne infections are spreading north in Europe. West Nile virus and Usutu are knocking on the door.

To determine the risk for introduction of mosquito borne zoonotic avian viruses like West Nile virus and Usutu virus we want to test blood samples from spring migrating birds at bird observatories in southern Sweden and also sero prevalence in fall migrating birds hatched the same summer to see if there is any circulation of the viruses in Swedish birds during summer.

Once a virus is introduced it needs competent vectors in sufficient numbers that can spread it in the resident bird population.

Therefore, we want to determine the vector competence of Swedish mosquito species for three important emerging zoonotic viruses, West Nile virus, Usutu virus and Rift Valley virus.

Another important factor for establishment and further spread is the abundance of competent vector species and therefore we want to investigate abundance of the main vector species, the Culex mosquitoes, in southern and northern Sweden.

The taxonomic situation of Culex mosquitoes is not resolved and to try to understand the situation in Sweden we want to do population genetics on Swedish Culex.To further study the risk of establishment and spread of these zoonotic viruses we want to investigate the endosymbiotic flora of Swedish mosquito species to evalute if there are differences between species and/or popoulations of the the same species that may effect their vector potential.