Pregnant women should avoid traveling to Latin America and Caribbean countries that have outbreaks of a tropical illness linked to birth defects, health officials said Friday.
The illness is caused by the Zika virus which is spread through mosquito bites. It causes only a mild illness in most people. But it's been spreading around the world, and there's mounting evidence linking it to a terrible birth defect, especially in Brazil.
Late Friday, US health officials said pregnant women should consider postponing trips to 14 destinations – Brazil, Colombia, El Salvador, French Guiana, Guatemala, Haiti, Honduras, Martinique, Mexico, Panama, Paraguay, Puerto Rico, Suriname and Venezuela.
They also advised women who are trying to get pregnant or thinking of getting pregnant to talk to their doctor before traveling to those areas, and to take extra precautions to avoid mosquito bites.
What is Zika?
Zika (ZEE'-ka) is the name of a virus discovered in a monkey in the Zika forest of Uganda in 1947. It is native to tropical Africa, Southeast Asia, and the Pacific Islands. But infections have exploded recently in Latin America and the Caribbean. It is spread through bites from the same kind of mosquitoes that can spread other tropical diseases, like chikungunya and dengue fever.
What are the symptoms?
Experts think that only about 1 in 5 people who are infected with the Zika virus develop any symptoms. For those that do, Zika illness usually involves fever, rash, joint pain, and red eyes – which usually last no more than a week. There is no medicine or vaccine for it. Hospitalizations are rare, and deaths from Zika have not been reported.
Why is it a concern now?
Two reasons. First, there's been growing evidence linking Zika infection in pregnant women to a rare condition called microcephaly, in which the head is smaller than normal and the brain has not developed properly. US health officials are heading to Brazil, where there's been a recent spike in the birth defect, to further study the actual risk to pregnant women. More than 3,500 cases have been reported in Brazil since October.
Second, the threat seems to be moving closer. Infections are occurring in our southern neighbor, Mexico, and the kind of mosquitoes that can carry the virus are found along the southern United States, too. Experts think it's likely the pests may end up spreading the virus here, though probably on a smaller scale than what's been seen in the tropics.
Have there been cases in the US?
At least 26 Americans have been diagnosed with Zika since 2007, all of them travelers who are believed to have caught it overseas. In addition, a person in Puerto Rico who had not traveled was diagnosed with the illness last month.
What's the advice?
Last month, the Centers for Disease Control and Protection advised US travelers to protect themselves against mosquito bites if they visit places in Latin America or the Caribbean where Zika has been spreading. The advice includes wearing long sleeves and long pants and using insect repellent.
On Friday, the CDC came out with an alert asking pregnant women – at any stage of pregnancy – to postpone travel to 14 destinations in Latin America and the Caribbean.
In Brazil, most of the mothers who had babies with the condition – called microcephaly – were apparently infected during the first trimester, but there is some evidence the birth defect can occur later in the pregnancy, said the CDC's Dr. Cynthia Moore.
Another CDC official, Dr. Lyle Petersen, said the virus seems to remain in the blood only about a week or two.
Why hasn't a link between Zika and the birth defect been noted earlier? Previous outbreaks were much smaller, and the problem may have occurred less often – and so was harder to recognize, he said.
There's another travel alert for pregnant women already in place, discouraging travel to areas where malaria is spreading.