A study of women who were infected with the Zika virus late in pregnancy found that none had babies with apparent birth defects.
The study, published in the New England Journal of Medicine online Wednesday, seems to confirm that the greatest risk to infants comes early in pregnancy.
Researchers tracked women infected in Colombia and also found troubling cases of severe birth defects in babies born to women who never realized they had contracted Zika.
Zika virus is spread mainly through the bite of a tropical mosquito. It causes only a mild and brief illness, at worst, in most people and many don't even realize they've been infected. But it can cause fetal deaths and severe birth defects in the children of women infected during pregnancy.
