About one in seven babies exposed to Zika in the womb had health problems caused by the virus — including some medical complications that were not evident at birth and were identified only as the infants grew older, the nation’s top health agency reported on Tuesday.
The Centers for Disease Control and Prevention said the health issues possibly caused by Zika included birth defects — such as a small head size, brain and eye damage — and nervous system problems including seizures and vision and hearing loss.
“The Zika story is not over,” Peggy Honein, director of the CDC’s Division of Congenital and Developmental Disorders, said during a conference call with reporters.
Zika emerged in Miami in the summer of 2016, the first place in the continental United States to report local spread of the disease. By the summer of 2017, though, there were just two cases. No local Zika cases have been reported in 2018.
Honein said the CDC cannot say with certainty how many neuro-developmental problems, such as brain and eye damage, were caused by Zika infections in 2016 and 2017. But she added that the incidence of brain and eye damage was about 30 times higher in babies born to mothers who had Zika during pregnancy than it was in those babies who were not exposed to Zika in the womb.
“What makes this report unique,” Honein said, “is we’re looking at the health of these babies beyond what was observed at birth.”
The CDC report released Tuesday is the largest to date involving long-term health outcomes in babies born to mothers who had laboratory-confirmed evidence of Zika during pregnancy.
To conduct the study, the CDC examined 1,450 infants who were at least 1 year old by Feb. 1, 2018, and had some follow-up care. All of the children in the study were born in U.S. territories with local spread of Zika in 2016 and 2017, including Puerto Rico, American Samoa, the U.S. Virgin Islands, the Federated States of Micronesia and the Republic of Marshall Islands. No states were included in the study.
The new findings underscore the need for follow-up care of babies exposed to Zika before birth, said CDC Director Dr. Robert Redfield.
“We are still learning about the effects of Zika, and it might be years before we fully understand the full spectrum of health outcomes,” Redfield said. “We do know that some babies may appear healthy at birth but may develop long-term health problems as they grow.”
But follow-up care has been spotty for children born to mothers who had Zika during pregnancy, said Dr. Ivan Gonzalez, director of the Zika Response Team at the University of Miami Health System, a group of medical specialists who coordinate care for infants exposed to the virus before birth.
Gonzalez said the team monitors about 65 children born between 2016, when Florida began to monitor Zika infections, and 2018.
Ideally, Gonzalez said, the group should be tracking more children given the number of pregnant women with laboratory-confirmed Zika infections in Florida: a total of 479 since 2016, according to the Florida Department of Health. That number includes women who contracted the illness while traveling outside of Florida.
But persuading parents and pediatricians to follow CDC guidelines for follow-up care is proving difficult, said Gonzalez, who also serves as medical director of Florida’s Zika Referral Center, a statewide program that connects infected patients to doctors.
“Because Zika has become last year’s thing,” he said, “nobody cares.”
Gonzalez said parents and pediatricians who ignore follow-up care for children possibly exposed to Zika before birth risk missing early detection and interventions that could minimize the long-term effects of developmental problems, such as problems with vision, hearing and movement of their arms and legs.
Often, Gonzalez said, those problems may not become apparent until infants begin to miss developmental milestones, such as sitting up at 6 months, pulling up to stand at 9 months and walking at 1 year old.
“Right now they may look normal, but in a year or two years they may have developmental delays,” he said. “You may start to see other things that pop up. Unless you get the follow-up that’s needed, you will never catch that.”