The agent responsible for dengue, a flavivirus with 4 distinct serogroups, is not transmitted by direct inter-human infection, but only through the bite of Aedes mosquitoes . Once infected, these insects remain so for the duration of their life.
People affected by dengue are infectious to mosquitoes that sting them just before the onset of symptoms and for the duration of the febrile period (on average 5-7 days). In order to prevent further transmission by the vector insect, therefore, patients with dengue fever must be isolated with mosquito nets, at least until the resolution of the second febrile peak.
