Zika's Effect on Fetus May Be Worse Than Thought
But some scientists say link is still inconclusive
By Dennis Thompson
THURSDAY, Feb. 25, 2016 (HealthDay News) -- Zika virus may harm a fetus to a greater degree than previously suggested, potentially causing a range of life-threatening birth defects, a new report says.
The stillborn baby of a 20-year-old Brazilian woman infected with Zika had almost no brain tissue, which is a birth defect called hydraencephaly, according to the case study.
The fetus also suffered from microcephaly, the most common birth defect thought to be caused by the mosquito-borne virus. Children with this birth defect have underdeveloped heads and brains.
Most troubling, the fetus also showed the first reported birth defect potentially caused by Zika that affected a part of the body other than the central nervous system, according to the report authors.
Dangerous amounts of fluid buildup in the fetus caused swelling and damage to different parts of its body, a condition called hydrops fetalis, said the researchers, from Brazil and Yale University. They reported their findings in the Feb. 25 issue of the journal PLOS Neglected Tropical Diseases.
It's not certain that Zika was the cause of these abnormalities, and experts say many questions remain unanswered.
In fact, some medical professionals contend that Brazil and some international health officials prematurely declared a link between Zika and an apparent surge in birth defects.
Among them are 14 Brazilian and American researchers who said in the Feb. 24 Annals of Internal Medicine that the connection between the virus and microcephaly "remains presumptive." So far, the evidence is circumstantial, they wrote.
Others health experts said the evidence against the Zika virus is mounting.
Anecdotal reports of Zika causing birth defects other than microcephaly have surfaced, but "this is the first clearly documented case with an obvious link to Zika infection that has been well-documented in a peer-reviewed journal," Stephen Higgs, director of the Biosecurity Research Institute at Kansas State University, said of the PLOS study.
The case study shows that the U.S. Centers for Disease Control and Prevention was on the right track when it recommended that any pregnant woman who's been to a Zika-affected region be tested for the virus, said Dr. Veronique Tache, an assistant professor of maternal-fetal medicine at the University of California, Davis.