Zika virus is transmitted through mosquito bites. In humans, it causes a mild illness known as Zika fever, Zika, or Zika disease. The illness it causes is similar to a mild form of dengue fever and is treated by rest, and cannot be prevented by drugs or vaccines.
The most common symptoms of Zika virus disease are fever, rash, joint pain, and conjunctivitis, or red eyes. The illness is usually mild with symptoms lasting from several days to a week. Severe disease requiring hospitalization is uncommon.
Prior to 2015, Zika virus outbreaks have occurred in areas of Africa, Southeast Asia, and the Pacific Islands.
In May 2015, the Pan American Health Organization (PAHO) issued an alert regarding the first confirmed Zika virus infections in Brazil. The outbreak in Brazil led to reports of Guillain-Barre syndrome and pregnant women giving birth to babies with severe birth defects and poor pregnancy outcomes.
Currently, many other countries are reporting cases of Zika. Zika virus will continue to spread and it will be difficult to determine how the virus will spread over time.
No vaccine exists to prevent Zika. Prevent it by avoiding mosquito bites. Mosquitoes that spread Zika virus bite mostly during the daytime.
When traveling to countries where Zika virus or other viruses spread by mosquitoes are found, take the following steps: use insect repellents; treat clothing with permethrin or purchase permethrin-treated clothing, when weather permits, wear long-sleeved shirts and long pants; use air conditioning or window/door screens to keep mosquitoes outside. If you are not able to protect yourself from mosquitoes inside your home or hotel, sleep under a mosquito bed net.
Help reduce the number of mosquitoes inside and outside your home or hotel room by emptying standing water from containers such as flowerpots or buckets.
If you have Zika, protect others from getting sick. During the first week of infection, Zika virus can be found in the blood and passed from an infected person to another mosquito through mosquito bites. An infected mosquito can then spread the virus to other people.
To help prevent others from getting sick, avoid mosquito bites during the first week of illness. In addition, there has been one report of sexual transmission of the Zika virus, and one report of transmission through blood transfusion.
Prevention is the best means of combating the spread Zika and related illnesses.