Learn More About The Studies On Zika Virus And Birth Defects

CHICAGO, Feb 9 (Reuters) – At Roberto Santos General Hospital in Salvador, Brazil, Dr. Antonio Almeida and a team of specialists are closely following two groups of women: Those who deliver babies with abnormally small heads and those who deliver apparently normal babies.

The hospital is one of three in this city on Brazil’s eastern coast where investigators are studying the most urgent question of the Zika outbreak: Is the virus causing a spike in birth defects, and, if so, how great is the risk?

The answer will help shape the response to the rapid spread of Zika throughout the Americas. Concerns over the potential link to microcephaly have prompted a U.S. alert advising pregnant women against travel to 31 countries and territories with outbreaks.

Officials in El Salvador, Colombia, Ecuador and Jamaica have urged women to delay pregnancies. The many unknowns about Zika‘s effects and transmission have cast a shadow over plans for the Olympic Games in Rio, set to begin in early August.

The evidence so far is compelling enough that the World Health Organization declared an international health emergency Feb. 1. But it is mostly circumstantial: Suspected cases of microcephaly – a rare birth defect characterized by small head size and an underdeveloped brain – spiked 30-fold in late 2015, months after Zika‘s arrival in Brazil.

There is harder evidence as well. Brazilian researchers have isolated the virus in brain tissue and amniotic fluid of 17 babies and stillborn fetuses with microcephaly whose mothers had symptoms of Zika infection during pregnancy.

The finding provides scientific plausibility that Zika could cause microcephaly, a condition that can result in developmental delays as well as seizures, hearing loss, vision problems and trouble swallowing. They can range from mild to severe.

“We know the virus can cross the placenta,” said Dr. Albert Ko, a tropical disease specialist —> Read More