New Zika study warns of a 'global epidemic’ of birth defects

Pregnant women have even more reason to be concerned about the spread of the Zika virus after two reports published this week reinforced the connection between Zika and birth defects, and shed more light on the extent of those defects.

A study published on Thursday in the UK medical journal Lancet provided more evidence that Zika infection during pregnancy is responsible for babies born with microcephaly, a birth defect that results in small head size and an often underdeveloped brain.

Since a rash of microcephaly cases in Brazil last year coincided with an unprecedented outbreak of Zika, anecdotal and observational evidence has pointed to a connection between microcephaly and Zika infection in mothers. But researchers say the preliminary findings published in Lancet represent the first case-control study evaluating that hypothesis.

The study is ongoing at eight public hospitals in the Brazilian state of Pernambuco and will ultimately evaluate 600 babies. But researchers said they released early results after studying just 94 newborns this year due to the seriousness of what they were seeing.

"We are reporting the preliminary findings of our study because of the striking magnitude of the association between microcephaly and Zika virus infection," the report states. Researchers recommended that people "prepare for a global epidemic of microcephaly and other manifestations of congenital Zika syndrome."

Microcephaly is just one abnormality associated with the Zika syndrome in newborns, and a second Zika-related study, published on Wednesday by the US Centers for Disease Control, delved into the extent of those abnormalities by evaluating early growth and neurologic outcomes for babies with congenital Zika virus syndrome. Researchers looked at 48 affected babies in Brazil in the first eight months of their lives.

In addition to microcephaly at birth, physical development and growth continued to lag behind as the newborns aged. Researchers also noted common symptoms like irritability, sleep disorders, and difficulties being calmed down. Furthermore, neurologic problems like epileptic seizures and dysphagia appeared with age.

Public health experts around the world are eager for more studies on the connection between Zika and birth defects, with many questions still unanswered not only about the effects on newborns, but about the future those children will face as they grow up.

Follow Kayla Ruble on Twitter: @RubleKB