According to the Center for Disease Control, infection with<unk>  is seasonal in temperate zones. Climates that are temperate, such as those in the United States and Europe, see peak season from July to October. Peak season changes depending on geographic region and warmer and humid climates can see longer peak seasons. All ages are equally likely to be infected but there is a higher amount of death and neuroinvasive<unk>  in people 60–89 years old. People of older age are more likely to have adverse effects. There are several modes of transmission but the most common cause of infection in humans is by being bitten by an infected mosquito. Other modes of transmission include blood transfusion, organ transplantation, breast-feeding, transplacental transmission, and laboratory acquisition. These alternative modes of transmission are extremely rare.
West Nile virus
Western equine encephalitis virus
Venezuelan equine encephalitis virus
Dengue virus
Sepik virus
Rabies virus
Zika virus
Cricket paralysis virus