Zika virus disease is an emerging mosquito-borne viral infection. In the majority of cases, the virus is transmitted to people through the bite of an infected female Aedes mosquito which also transmits other diseases such as chikungunya, dengue and yellow fever. However, in a small number of cases, the Zika virus has occurred through sexual transmission or via the placenta from mother to foetus.
Signs and symptoms
Following a bite from an infected mosquito, the first symptoms can develop in 3-12 days; however, the incubation period can be shorter or longer in some people. In the majority of cases, infected individuals do not experience any symptoms – in travellers who do, the symptoms are usually mild, self-limiting and last for around 2-7 days.
Currently, there is no specific, antiviral treatment or vaccine available.
The best form of prevention is protection against mosquito bites. The Aedes mosquito bites
predominantly during the day, especially mid-morning and late afternoon to dusk. This is different to
malaria-transmitting mosquitoes which bite between dusk and dawn. It is, therefore, advisable to
practice bite avoidance measures. All travellers should also exercise precaution to avoid sexual transmission.