In December, the World Health Organization designated Zika as a "serious" emerging disease that requires action as soon as possible. Later that month, the first case of Zika in the United States was reported in Puerto Rico.
The following are five things to know about the Zika virus.
1. The Zika virus is spread through the bites of a certain type of mosquito located in tropical regions of the world that also spreads chikungunya and dengue viruses. According to the CDC, the most common symptoms of Zika are fever, rash, joint pain and conjunctivitis, and severe cases that require hospitalization are rare.
2. Even though Zika virus is not usually life-threatening, there have been links between infected pregnant women and poor pregnancy outcomes, including microcephaly, a condition in which a baby's head is much smaller than expected. In response to this link, the CDC issued interim guidelines for pregnant women during a Zika virus outbreak earlier this month.
3. Diagnosing Zika virus can be difficult, as it presents similarly to dengue, malaria and several other viruses, according to the CDC. Diagnosis should be based on symptoms as well as places and dates of travel, and there is a lab diagnostic test. Zika is not a nationally reportable disease in the U.S., but the CDC urges healthcare providers to report a suspected case to the local or state health departments.
4. There is no specific treatment or vaccine available for Zika virus. The CDC recommends treating the symptoms, including drinking fluids, getting rest and taking medication to help the fever and pain.
5. While outbreaks of Zika virus have occurred in tropical areas of the world, the disease is spreading as the mosquitoes spread. There have been no locally transmitted Zika cases in the U.S., other than the case in Puerto Rico. However, there have been several Zika cases confirmed in travelers returning to the U.S. — according to the Washington Post, there are roughly a dozen such cases in the U.S.