95% of Prenatal Zika Infections Could Be Undiagnosed in Infants

With over 24,600 Zika virus cases already confirmed in the Region of the Americas in 2024, a new study published by the journal eBioMedicine, part of The Lancet, disclosed new, unsettling insights.

The Cleveland Clinic announced that this study revealed that maternal Zika virus infections can reprogram fetal immune development, leading to long-term consequences in children's immunity.

On July 18, 2024, the Clinic stated that these changes may occur in children born without the physical characteristics associated with congenital Zika syndrome, such as microcephaly.

This finding suggests that 95% of babies born from Zika-infected pregnancies who did not exhibit symptoms may have been affected by the virus with long-term immunological repercussions.

Additionally, heightened inflammation was observed in Zika-exposed infants with abnormalities at birth, while children exposed to Zika later maintained a chronic Th1-biased immune profile. The impaired response to Th2-biased vaccines raises concerns about the lasting effects of Zika virus exposure on immune responses.

Suan-Sin (Jolin) Foo, PhD, an expert in maternal-fetal virology and the Zika virus, says babies without symptoms are deemed healthy and do not receive any follow-up medical care or attention. 

“Studies have only really focused on what’s happening with the children who were born with visible physical conditions like microcephaly or neurological complications,” Dr. Foo commented in a press release.

“The rest of these kids may not even have a note on their chart mentioning that their mother was infected during pregnancy. Unless they’re part of our study, they’re essentially lost to the medical field.”

Dr. Foo added, “Our study clearly shows there’s much more to this condition than meets the eye. We need to expand diagnostic criteria and conduct more research to ensure these immunologically vulnerable children get the necessary care.” 

From a prevention perspective, no Zika vaccine candidate has been approved by the U.S. FDA as of July 2024.