Infectious diseases expert Sharone Green, MD, is paying close attention to the suspected link between the Zika virus and microcephaly, a birth defect in which babies are born with small heads and underdeveloped brains. Dr. Green plans to research Zika in her lab and hopes to shed light on the connection.
“There seems to be something about this virus that is very unusual,” said Green, associate professor of medicine in the Division of Infectious Diseases and Immunology.
Green studies viral infections, including West Nile virus, yellow fever virus and dengue viruses, which are all in the same family as Zika virus. There’s a theory, according to Green, that Zika virus could be contributing to a higher rate of microcephaly because it is spreading in a population in which a large number of people have previously been infected with dengue, a virus closely related to Zika.
“A person infected with one type of dengue will become immune against that type for life, but it will not offer any protection for other forms of the virus,” she said. “Getting infected with a second type of dengue raises the risk of a person developing a more severe complication related to dengue.What’s happened now is that you have a virus that went from Africa, which had a little bit of dengue, to the island of Yap in Micronesia, which had some dengue, to French Polynesia, which had a lot more dengue and physicians started to notice a neurological complication known as Guillain-Barre syndrome. As the virus now has started to move to Central America and Brazil, which have much larger populations, with an even higher prevalence of dengue, the severe microcephaly suddenly becomes noticed.”
Like dengue, Zika is primarily transmitted by the day-time biting mosquitoes called Aedes aegypti, a species common in countries such as Brazil that are experiencing Zika outbreaks. While the mosquito can be found in areas of the United States, including southern and south-eastern states, it is not native to Massachusetts. As of Feb. 24, The Centers for Disease Control and Prevention reported 107 cases of Zika in the United States from people who contracted it while traveling in an affected country. No incidents of the disease spreading via mosquitos in the United States have been reported.
