The previously little-known virus that re-emerged in Brazil in 2015 has now shown itself to be a possible threat to the continental United States.
The World Health Organization has warned that the mosquito-borne virus is almost guaranteed to infiltrate every country and territory in the Americas - including the U.S. (See below.)
A baby born in Hawaii with an unusually small head contracted the Zika virus while in utero. The mother most likely had the infection while she was residing in Brazil. Authorities there have taken the unusual step of warning women against getting pregnant while the Aedes mosquito is a threat.
The CDC has issued a warning about traveling to 13 South American countries, especially women who are pregnant. Three women in Florida have already contracted the virus. All three cases are confirmed to be non-pregnant women who had traveled to either Colombia or Venezuela. A case has been confirmed in Arkansas in a person who had traveled outside of the U.S.
Here are six things to know about the virus:
1. What is Zika?
It was first isolated in 1947 and is named for a forest in Uganda. The Zika virus has similar symptoms to dengue and chikungunya — rash, joint pain, fever. Like those syndromes, Zika is mosquito-borne. The virus is also linked to microcephaly, an abnormal smallness of the head in infants, and so Zika is especially dangerous for pregnant women.
2. Has it spread to the United States?
Yes. There are three women in Florida who’ve contracted it — none are pregnant. However, according to Vox, there’s been one “Zika birth” in the U.S. so far - the one in Hawaii. Two other pregnant women, both in Illinois, have also contracted Zika. Cases have been confirmed in 11 states in the U.S. - all in individuals who traveled outside the U.S.
3. Has there been a "locally" transmitted case in the U.S.?
No. The U.S. Centers for Disease Control says that there has not yet been a confirmed case of Zika virus that was transmitted inside the U.S. All confirmed domestic cases occured when those individuals traveled outside the country.
4. Are American citizens who have not traveled outside the U.S. in danger?
Yes. The World Health Organization has warned that the virus is projected to spread across the Americas into every country and territory where the Aedes mosquitos are found. That includes the United States. Scientists are looking into whether the virus can be sexually transmitted between partners.
Scott Weaver with the Institute of Human Infections and Immunity at the University of Texas, told Vox: “It’s going to be knocking on the doorstep in places like Florida and Texas, probably in the spring and summer.”
5. What are the symptoms?
According to the CDC's explainer on Zika, about 1 in 5 people who are infected with the Zika virus become ill. Severe illness requring hopsitalization is uncommon, and deaths are rare. These are the symptoms:
- The most common symptoms of Zika are fever, rash, joint pain, or conjunctivitis (red eyes). Other common symptoms include muscle pain and headache. The incubation period (the time from exposure to symptoms) for Zika virus disease is not known, but is likely to be a few days to a week.
- The illness is usually mild with symptoms lasting for several days to a week.
- Zika virus usually remains in the blood of an infected person for a few days but it can be found longer in some people.
6. What can I do?
The Pan American Health Organization released the following recommendations for stymieing the spread of Zika virus:
- Mosquito populations should be reduced and controlled by eliminating breeding sites. Containers that can hold even small amounts of water where mosquitoes can breed, such as buckets, flower pots or tires, should be emptied, cleaned or covered to prevent mosquitoes from breeding in them. This will also help to control dengue and chikungunya, which are also transmitted by Aedes mosquitoes. Other measures include using larvicide to treat standing waters.
- All people living in or visiting areas with Aedes mosquitoes should protect themselves from mosquito bites by using insect repellent; wearing clothes (preferably light-colored) that cover as much of the body as possible; using physical barriers such as screens, closed doors and windows; and sleeping under mosquito nets, especially during the day when Aedes mosquitoes are most active.
- Pregnant women should be especially careful to avoid mosquito bites. Although Zika typically causes only mild symptoms, outbreaks in Brazil have coincided with a marked increase in microcephaly—or unusually small head size—in newborns. Women planning to travel to areas where Zika is circulating should consult a healthcare provider before traveling and upon return. Women who believe they have been exposed to Zika virus should consult with their healthcare provider for close monitoring of their pregnancy. Any decision to defer pregnancy is an individual one between a woman, her partner and her healthcare provider.