Zika virus outbreaks have been detected in Africa and southeast Asia for decades – but only in recent years have scientists detected transmission elsewhere. The virus causes mild, flu-like symptoms – like low-grade fever, rash, fatigue and muscle pain – that last about a week, but can cause a birth defect called microcephaly and other severe fetal brain defects.
West Nile virus is the most commonly reported mosquito-borne disease in the United States. Although only one in five people who contract the virus develop symptoms such as fever, headache, body aches or vomiting, the virus can cause serious neurological illnesses that can be fatal, such as encephalitis or meningitis.
Dengue fever is primarily thought to be a tropical disease, but occasional cases have been detected in southern states, including Texas and Florida, in recent years. Symptoms include high fever, severe headache behind the eyes, rash and muscle pain.