Ascension Island: a survey to assess the presence of Zika virus vectors.

BACKGROUND AND AIM: Following concerns regarding the spread of Zika virus, Joint Services Health Unit (Cyprus) were tasked to carry out a mosquito survey on the Ascension Island, South Atlantic. This was to determine if vectors of the virus such as Aedes aegypti and Aedes albopictus were introduced and established on the Island.

METHODS: An extensive survey of residential areas and natural habitats was initiated in order to collect mosquito larvae and adults by methods such as larval sampling, adult trapping and human landing catches.

RESULTS: A. aegypti or A. albopictus were not collected by any of the three methods employed. Culex quinquefasciatus was the only species collected by all three methods. C. quinquefasciatus is a vector of lymphatic filariasis that can easily be transported by human means by air or sea. It is a container breeding species that lives in close proximity to human settlements and can cause significant amount of nuisance.

DISCUSSION: Ascension Island is connected by air and sea with areas of the world where container breeding species such as A. albopictus and A. aegypti are established, therefore, it is not unlikely that these species become introduced to Ascension in the future. Sound surveillance on Ascension is imperative in order to act as an early warning and rapid response system for invasive mosquito species as well as a guide for the implementation of control measures against C. quinquefasciatus .