CDC Concludes that Zika Causes Fetal Birth Defects

On Wednesday, scientists at the Center for Disease Control (CDC) issued a press release identifying a causal relationship between prenatal Zika infection and cases of “microcephaly and other severe fetal brain defects.” A special report was also published in the New England Journal of Medicine detailing the processes used to evaluate the current information around the primarily insect vector-borne disease’s effects on mothers and infants.

CDC Concludes that Zika Causes Fetal Birth Defects

(Aedes aegypti bites are the primary mode of Zika transmission. Source: James Gathany/CDC)

A woman infected with Zika during pregnancy faces a higher risk of giving birth to a baby with unusually small head size (microcephaly), brain damage, and other neurological complications. While no single piece of data definitively proves the CDC’s conclusions, the organization utilized growing evidence from numerous recent studies and “careful evaluation using established scientific criteria” to support their findings. Tom Frieden, M.D., M.P.H., and director of the CDC tweeted on the precedent of these findings:

Dr. Frieden also commented within the press release, “This study marks a turning point in the Zika outbreak … We’ve now confirmed what mounting evidence has suggested, affirming our early guidance to pregnant women and their partners to take steps to avoid Zika infection and to health care professionals who are talking to patients every day.”

In February, the World Health Organization (WHO) declared the Zika outbreak as an international public health crisis. The CDC intends this announcement to be an important step towards “…driving additional prevention efforts, focusing research activities, and reinforcing the need for direct communication about the risks of Zika.” The WHO has reported that 62 countries and territories have already reported transmission of the virus. And according to a New York Times article, 700 people have already been infected by Zika in the United States.