The Zika virus is spreading rapidly across the Americas, prompting the World Health Organization to declare a global emergency on Monday.
So what do you need to know about the Zika virus?
A mosquito-transmitted infection, the virus causes no symptoms and leads to no lasting harm in most who contract it. But for pregnant women, infection has been linked to a birth defect called microcephaly, which causes babies to be born with abnormally small heads and brains. More than 4,000 cases of the condition have been confirmed in Brazil since October.
“The great scare comes from all the data with respect to these birth defects, which are very dramatic,” said Oklahoma Medical Research Foundation President Stephen Prescott, M.D., a physician and medical researcher. “Affected children are born with small brains and very significant deficits in life. Experts also have linked Zika to miscarriages and other pregnancy complications, so it certainly deserves the world’s attention.”
“We do not know yet how significant the threat to Oklahoma might be, but the virus is now widespread throughout much of South and Central America,” said OMRF immunologist Hal Scofield, M.D. “There have been confirmed cases in the U.S. in persons traveling to these areas.”
Researchers predict that Southern states along the Gulf coast, in particular, could be affected because of the presence of the Aedes aegypti mosquito, an aggressive mosquito that has spread most cases of Zika. The Asian tiger mosquito, which commonly lives through the winter in Oklahoma, may also be a vector for transmission, said Scofield. However, U.S. health officials have said that the risk of a U.S. outbreak is low, largely due to more effective mosquito control.
“For the average American who is not traveling to this area, there is nothing they need to worry about,” Dr. Anne Schuchat, principal deputy director of the federal Centers for Disease Control and Prevention, told The New York Times.
There is some evidence that Zika may also be transmitted sexually, but the risk remains unknown at the time.
While it can be potentially devastating for pregnant women and their babies, the effects on others, if any, are far less severe. The most common symptoms include conjunctivitis, joint pain, fever and rash. The symptoms are often mild and last up to a week, and the need for hospitalization is uncommon. The Centers for Disease Control and Prevention say only about one in five of those infected will get sick, and most others will not even realize they have contracted the virus.
Disease specialists in Brazil say that the virus may also be causing a surge in another rare condition, Guillain-Barré syndrome, which leaves some patients unable to move and dependent on life support. Although the CDC has described reports linking the two conditions as “anecdotal,” the agency is helping Brazil conduct a study to evaluate if any connection exists.
So what’s the best way to protect yourself against Zika?
“Avoid travel to South and Central America,” said Prescott. “And don’t get bitten by mosquitoes.”
That means preventing standing water from collecting around your home and using insecticides where appropriate to prevent mosquitoes from breeding. Apply repellant when you’re going to be outdoors in peak mosquito hours. Close windows and keep sleeping areas mosquito-free, especially as temperatures start to warm.
“I know it sounds difficult to avoid getting bitten, but scale what you do to the risk,” said Prescott. “Do anything that protects you, and women early in pregnancy or planning on becoming pregnant should, as always, take the most precautions.”
UPDATE: The CDC has confirmed a sexually-transmitted case of Zika virus in Texas.