October 9, 2019
In 2015, Zika virus swept through Brazil and the Americas. It was the first time a mosquito-borne virus was known to cause severe birth defects, and the World Health Organization declared it a “public health emergency that warranted a global response.”
“This was a truly unprecedented phenomenon,” says Dr. Albert Ko, an epidemiologist at Yale who has worked in Brazil for over two decades. “There was a new, emerging pathogen in the world.” The pandemic’s emergency status was lifted in November 2016. But it left more than 3,700 children born with birth defects — the most severe of which is microcephaly, where babies are born with small heads and brain damage — in its aftermath.
In the three years since it ended, the pandemic has become an object of obsession for scientists, who have published more than 6,000 research papers about it. What did they conclude? To find out, Ko and two colleagues reviewed a selection of those publications. They found that researchers have been able to follow long-term health consequences in children infected with the virus before birth. But progress on beating the pandemic turned out to be an impediment to further research into vaccines and diagnostics that could help prevent other epidemics in the future.