Arthropod vectors play important roles in the transmission of hundreds of different viruses, many of which can severely affect human and animal health. Changing environmental factors and human development can support the establishment of invasive arthropod species, affect the vector competence of endemic species, and enhance viral fitness/virulence, thereby potentially contributing to the spread of emerging viral diseases. For example, the Asian tiger mosquito, Aedes albopictus, originally endemic in South-East Asia, has over the past approx. 40 years spread throughout large parts of the Americas, Africa, Australia, and Southern Europe and Switzerland as well. A. albopictus is known to transmit many different human viruses, including chikungunya virus, dengue virus, and zika virus, although such incidences have not yet been reported in Switzerland. Nevertheless, as the presence of the vector clearly facilitates that possibility in the future, this research project aims to determine the full, unbiased viral population diversity of A. albopictus as well as that of endemic mosquito species collected in the Canton Ticino. This is a collaborative project with the “Laboratorio di microbiologia applicate, Scuola universitaria professionale della Svizzera italiana” (SUSPI).