CDC: Birth defect rate 20 times higher for infants with Zika-infected mothers
MelissaJenco, News Content Editor
Infants whose mothers were infected with Zika virus had rates of birth defects that
were 20-times higher than those born in the years just prior to the epidemic, according
to a new study.
The Centers for Disease Control and Prevention (CDC) found 6% of infants with an infected
mother developed birth defects compared to 0.3% of those whose mothers were not infected.
“These data demonstrate the critical contribution of population-based birth defects
surveillance to understanding the impact of Zika virus infection during pregnancy,”
researchers said in the study published Thursday in the Morbidity and Mortality Weekly Report.
The CDC compared data from 2013-’14 (before Zika’s introduction in the U.S.) from
Massachusetts, North Carolina and Georgia to 2016 data from the U.S. Zika Pregnancy
Registry. In the pre-Zika period, 747 infants and fetuses had at least one of the
birth defects that have been linked to the virus (2.86 per 1,000). Among those with
Zika-infected mothers last year, 26 of 442 (58.5 per 1,000) had birth defects. The
rate for the pre-Zika period is for live births while the rate for 2016 represents
Brain abnormalities and microcephaly were most common in both groups and were 33 times
higher in those whose mother was infected. Other birth defects included neural tube
defects, eye abnormalities and other consequences of central nervous system dysfunction
like joint contractures.