ARI SHAPIRO, HOST:
The U.S. Centers for Disease Control and Prevention is considering a travel warning because of a virus that could be harmful to pregnant women and their babies. It's called the Zika virus. It may be causing babies in Brazil to be born with brain damage. NPR's Jason Beaubien reports.
JASON BEAUBIEN, BYLINE: The Zika virus is named after the Zika Forest in Uganda where it was first identified in the 1940s. For decades, it was a rare disease, primarily popping up in Africa and occasionally in Southeast Asia. In 2007, there was a major Zika outbreak in Micronesia. Then in May of 2015, it turned up in Brazil.
NIKOS VASILAKIS: And within a year, it has just spread throughout the continent.
BEAUBIEN: Nikos Vasilakis at the University of Texas Medical Branch in Galveston says there's great concern about Zika because this once sleepy, mosquito-borne virus is now spreading rapidly.
VASILAKIS: The Brazilian minister of health estimates that anywhere between half a million to 1.5 million people may be infected by the virus.
BEAUBIEN: Last month, the World Health Organization said Zika had spread to eight other countries in the hemisphere. This month, the WHO upped that tally to 14 nations in the Americas. Usually, the virus causes a mild cold, but now it appears that Zika may also be causing babies to be born with small heads and severe brain damage. Brazil has seen this particular form of birth defect called microcephaly skyrocket from 150 to 200 cases a year to more than 3,000 cases in 2015. Vasilakis has been working in northeastern Brazil to help set up monitoring systems for Zika. He says these 3,000 cases are just the tip of the iceberg.
VASILAKIS: We're seeing the events that occurred about 6 or 7 months ago during the first trimester of pregnancy
BEAUBIEN: That means there could be more babies on the way with these severe forms of brain damage. The situation is so bad that some health officials in Brazil have suggested that women in places with high rates of Zika transmission should avoid getting pregnant. The U.S. Centers for Disease Control and Prevention is considering a travel warning for pregnant women who are heading to Zika-endemic countries, which currently means much of Latin America and the Caribbean. Lyle Petersen, who's leading the CDC's response to the Zika outbreak, says the virus poses a serious threat to travelers.
LYLE PETERSEN: Given the potential and increasingly strong association with these birth defects, this is a matter of some considerable concern.
BEAUBIEN: Petersen says travelers can protect themselves by taking steps to avoid getting bitten by mosquitoes, which he adds was an important thing to do in the tropics even before Zika showed up. Any new travel warning could be devastating to the local tourism industry. Nikos Vasilakis at the University of Texas, however, says that given the damage that this virus may cause to fetuses, he thinks a warning to pregnant women is prudent.
VASILAKIS: If my wife was pregnant or planning to be pregnant, I would not feel comfortable - her traveling to those areas.
BEAUBIEN: The CDC is expected to come out with some new guidance for pregnant women about traveling to Zika-affected countries soon. Jason Beaubien, NPR News.