Jamaica is now in the midst of a dengue outbreak. Like chikungunya and Zika, dengue fever is a mosquito-borne tropical disease caused by a virus. Unlike chikungunya and Zika, however, dengue is endemic to Jamaica. In other words, it is always in the envrionment somewhere in the on island. There are four types, known as serotypes, of the virus that causes dengue: DEN-1, DEN-2, DEN-3, DEN-4. Infection occurs when one is bitten by a female mosquito, usually Aedes aegypti, carrying the virus. The mosquito becomes infected when it sucks the blood of a person infected with the virus, and after about a week, the mosquito can then transmit the virus to another person.