What's Behind Brazil's Alarming Surge in Babies Born with Small Heads
What's Behind Brazil's Alarming Surge in Babies Born with Small Heads
by Dina Fine Maron | January 08, 2016 08:55pm ET
Thousands of Brazils newborns last year had abnormally tiny heads and potentially debilitating brain damage. In 2015 the country reported nearly 3,000 cases of the incurable condition, called microcephalyabout 20 times more than the prior year. In the nations northeast, where most of the cases occurred, government officials have already declared a state of emergency. Now international researchers and Brazilian authorities are rushing to tamp down the problem.
The trouble is they are not sure exactly what is causing the phenomenon or how to address it. They do have one strong suspecta mosquito-borne disease called Zika that usually causes short-term rashes and joint aches, and is plaguing the same areas in Brazil. There is already evidence the virus can cross the placental barrier: Zika has been detected in the amniotic fluid of two pregnant women with microcephalic fetuses in the state of Paraiba. Whats more, viruses from the same genus have the ability to replicate once they reach the central nervous system, providing some indication of how the viruses could potentially cause microcephaly in the first place.
Zika disease, however, has never been known to cause microcephaly before. (Microcephaly is typically caused by exposure to toxic substances during pregnancy, genetic abnormalities or diseases during pregnancy like rubella or herpes). Then again, scientists also know very little about Zika. In fact, until 2007 there were only sporadic cases of people infected with the virus (at least ones that were laboratory confirmed), with small outbreaks in Africa and Southeast Asia since being discovered in 1947 in Uganda.
Now, the Zika virus is rapidly advancing across new terrain. In May 2015 Brazil reported its first case of Zika and by December 2015 the virus had made its way into several countries in Central and South America, such as Colombia and Mexico, and even showed up on the island of Puerto Rico. The rapid spread suggests a change in the Zika virus, one which scientists are racing against the clock to pinpoint. Worryingly, Zika has also been linked with the future development of GuillainBarré syndrome, an autoimmune disease that could lead to paralysis.
More:
http://www.livescience.com/53317-whats-behind-brazils-alarming-surge-in-babies-born-with-small-heads.html
Science:
http://www.democraticunderground.com/122844657