One in seven babies born to Zika-infected mothers in Puerto Rico and other U.S. territories had some form of defect linked to the mosquito-borne virus, the Centers for Disease Control and Prevention said Tuesday.
The new study is the largest of its kind since a massive Zika outbreak sparked travel warnings in 2016 and forced couples to rewrite their travel plans. And while case counts have slowed to a trickle, parents are dealing with the fallout from the epidemic that once blanketed the Americas.
“The Zika story is really not over, especially for these children,” Dr. Peggy Honein, CDC’s director of the Division of Congenital and Developmental Disorders, told The Washington Times.
Scientists looked at 1,450 Zika-exposed infants who were born in U.S. territories in 2016 and early 2017 and had some form of follow-up care.
They found that 6 percent were born with a defect from the virus, such as an abnormally small head or a weakened optic nerve — a rate that’s 30 times higher than the typical population with no exposure to Zika.
Nine percent developed a neurologic abnormality, such as hearing or vision loss, seizures or trouble swallowing, that were possibly tied to the disease.
One percent suffered from both birth defects and neurodevelopmental problems.
Scientists who tracked Zika-exposed infants until they were at least one year old said the findings underscore the need for follow-up care, such as cranial scans or intensive eye exams, since some problems can develop well after birth.
For instance, researchers said 20 infants were born with normal-sized heads but suffered from a smaller head size — known as microcephaly — after they failed to grow properly during the first year.
The CDC said children may also need things such as speech therapy to help them lead normal lives.
Besides Puerto Rico, which accounted for the bulk of the cases, the new study looked at the territories and freely associated states of American Samoa, the Federated States of Micronesia, Marshall Islands and the U.S. Virgin Islands.
Previously, the CDC in 2017 released a study that found a 10 percent defect rate in babies born to mothers in the continental U.S. with lab-confirmed Zika.
Researchers said the findings in the territories add to a growing body of evidence that anywhere from 5 percent to 10 percent of Zika-exposed infants will suffer problems.
A rash of Zika cases in Brazil, Colombia and other parts of Latin America caused a global panic in 2015, yet the virus has largely burned out in the Americas since then, after a huge swath of the at-risk population developed immunity from the first wave.
In the continental U.S., there haven’t been any cases by mosquito bite at all in 2018, compared to seven in 2017 and more than 220 in 2016.
Travelers returning to the states and D.C. have reported only 34 cases, compared to hundreds of travel cases in 2017 and nearly 5,000 in 2016.
The territories have seen 74 cases by mosquito bite so far this year, down from tens of thousands at the height of the epidemic, though scientists say transmission is still being detected in parts of Latin America, Africa, southeast Asia and could re-emerge in at-risk states, so pregnant women and couples looking to conceive should be wary.
“The bottom line is Zika has not gone away, and we must remain cautious,” said CDC Director Robert Redfield.