Zika is caused by a virus that is transmitted primarily by the bite of an infected Aedes aegypti mosquito, which also transmits dengue and chikungunya and is found in over 100 countries worldwide. It can also be transmitted through sexual contact (sexual transmission), from a pregnant woman to her fetus (also known as vertical transmission), and through blood transfusion. The virus can be present without people being aware of it. In fact, about 80% of those infected with the Zika virus are asymptomatic and/or have really mild symptoms. As a result, there is low perceived risk. In the absence of a vaccine, effective strategic change communication is an effective tool to address behavior-related aspects of Zika transmission.
