Zika virus is spread to people primarily through the bite of an infected mosquito. It can also be passed from a pregnant woman to her fetus and through sex with a person who is infected with Zika. The most common symptoms of Zika virus disease (or Zika) are fever, rash, joint pain, and conjunctivitis (red eyes). Many people with Zika won’t have symptoms so they may not know they are infected. For those who do have symptoms, the illness is usually mild and can last for several days to a week. Zika infection during pregnancy can cause birth defects. There is no vaccine to prevent or medicine to treat Zika. Severe disease requiring hospitalization is uncommon and deaths are rare. The Aedes mosquitoes that spread Zika virus are found throughout the world.
*In some places, such as Puerto Rico, where permethrin products have been used for years in mosquito control efforts, mosquitoes have become resistant to it. In areas with high levels of resistance, use of permethrin is not likely to be effective.