4 in 10 babies born after Zika infection may have brain defects

Noted: Several scientists not involved in the study noted that the effect it recorded might be artificially high, because all women who had Zika had a symptomatic infection. It’s known that most people who contract Zika don’t have symptoms, and women with those milder infections may not give birth to babies with birth defects at the same rate, suggested Dave O’Connor, a professor of pathology and laboratory medicine at the University of Wisconsin-Madison who has been studying Zika in non-human primates.