Sciensano is responsible for the epidemiological surveillance of several mosquito-borne diseases in humans and animals and for the passive surveillance of exotic Aedes mosquitoes in Belgium. In addition, research is carried out to evaluate the competence of native mosquitoes for selected mosquito-borne diseases and on virus-vector-host interactions.
Mosquito-borne diseases are infectious diseases caused by bacteria, parasites or viruses, that are transmitted by the bite of an infected mosquito. The burden of these diseases is highest in tropical and subtropical areas, but some diseases are emerging in Europe.
How are mosquito-borne diseases transmitted?
Mosquito-borne diseases are spread by the bite of an infected mosquito. Although there are around 3,500 species of mosquitoes in the world, only a few (about hundred) are responsible for the transmission of pathogens to humans and animals. Only female mosquitoes can transmit pathogens because they are the ones feeding on blood to acquire proteins for the development of their eggs.
The mosquito itself can become infected when it bites an infected host (animal or human) that carries the pathogen in its blood. The pathogen develops in the mosquito, which then transmits it when it bites a new host.
The burden of mosquito-borne diseases
The burden of mosquito-borne diseases is highest in tropical and subtropical areas. However, some native mosquito species, such as Culex pipiens, are major vectors of both West Nile and Usutu viruses, which are emerging diseases in Europe. In addition, the exotic Asian tiger mosquito (Aedes albopictus), is rapidly spreading in Europe as a result of increased globalisation and climate change, leading to autochthonous cases of dengue and chikungunya in some countries.