What is Zika?
Zika is a mosquito-borne virus that is sweeping through South and Central America. Its initial symptoms are mild. The main ones, according to the U.S. Centers for Disease Control and Prevention, are "fever, rash, joint pain and conjunctivitis" or red eyes. Severe cases can linger for up to a month and sometime send patients to the hospital.
The real threat, according to the CDC, seems to be a link between Zika and a serious birth defect called microcephaly, in which the baby’s head is unusually small "compared to babies of the same sex and age." The defect has shown up in the babies of women infected with Zika during pregnancy.
The World Health Association says the virus’ arrival in Brazil also has been associated with a rise there in cases of Guillain-Barre syndrome, a rare disorder that can produce muscle weakness and even paralysis.
The CDC says that "knowledge of the link between Zika and these outcomes is evolving." Until more is known, it recommends "special precautions for the women who are pregnant or trying to become pregnant."
Likewise, the WHO says "a causal relationship between Zika virus infection and birth defects and neurological syndromes has not been established but is strongly suspected." It’s convening an emergency meeting Monday in Geneva on the virus.
FILE – A neurologist measures the head of a baby suspected of having microcephaly, at Mestre Vitalino Hospital in Caruaru, Pernambuco state, Brazil. The condition may be linked to the mosquito-borne Zika virus.
Where did it come from?
Zika was discovered in 1947 in Uganda's Zika forest. Up until 2007, outbreaks were rare and narrowly confined to areas of Africa and Southeast Asia. But in the past decade, epidemics have been reported in Micronesia and Polynesia, Easter Island, the Cook Islands and New Caledonia.
The first case in South America was identified last May in Brazil. Since then, the disease has spread rapidly through most of Central and South America. Brazil’s health ministry recently reported more than 4,000 suspected cases of microcephaly since October, compared with less than 150 in all of 2014, the Associated Press reported this week.
How many cases have been reported?
So far, more than 1 million cases have been reported in Brazil alone. But the WHO says it expects the disease to affect between 3 and 4 million people before it runs its course. Only an estimated one in five people exposed to the disease will become ill, but all of them can transmit the disease through mosquitoes feeding on them and then infecting other people.
What is the treatment?
There is no vaccine or medical treatment currently available for Zika. The WHO and the CDC recommend rest, plenty of fluids and acetaminophen for fever and pain. The CDC recommends that infected patients avoid mosquitoes because "Zika virus can be found in the blood and passed from an infected person to another mosquito through mosquito bites."
What can I do to avoid getting the disease?
The CDC has issued a Level 2 alert and has urged travelers to the region to practice "enhanced precautions" to avoid getting bitten by mosquitoes. This includes wearing long-sleeved shirts and long pants, using insect repellants containing DEET or permethrin-treated clothing. Finally, sleep in covered or air-conditioned areas.
Also, women who are pregnant, in any trimester, should consider postponing travel or at least talk with a doctor about the best ways to avoid mosquito bites. The same goes for women who are trying to become pregnant.
FILE - A graduate student analyzes samples to identify the Zika virus in a laboratory at the Fiocruz institute in Rio de Janeiro, Brazil, Jan. 22, 2016.
What is being done to stop Zika?
Any number of researchers and research institutions are looking for a vaccine and a treatment. Until they’re successful, the best way to fight the disease is to combat the mosquitoes that carry the virus.
Officials in Brazil and some of the 22 other countries reporting Zika cases are conducting mass spraying of pesticide and urging citizens to empty any standing water containers as a way to prevent breeding grounds for mosquitoes.