how dengue is spread
After a mosquito feeds on the blood of someone infected with the dengue virus, that mosquito becomes a dengue vector. The mosquito must take its blood meal during the period of viremia, when the infected person has high levels of the dengue virus in the blood. Once the virus enters the mosquito’s system in the blood meal, the virus spreads through the mosquito’s body over a period of eight to twelve days. After this period, the infected mosquito can transmit the dengue virus to another person while feeding.