What we know and don’t know about Zika, its history and its effects

The Zika virus is one of millions in the world. However, after the recent and growing outbreak of the mosquito-borne infection, scientists have renewed efforts to understand and fight the disease that has now been linked to birth defects in children of infected mothers.

Because of the potential for those devastating birth defects, the World Health Organizations has declared the disease a “public health emergency of international concern,” and work is underway by researchers to develop a vaccine.

While the infection was first identified in the late 1940s, we still don't know a lot about it.

Here’s a quick look at what we know and what we don’t know about the virus.

What we know

• Zika is a virus, transmitted by mosquitoes.

• As many as 80 percent of those who are infected will have no symptoms. If you experience symptoms, they are generally mild – low fever, joint and muscle pain, a rash. For a low percentage of adults, the virus can lead to another condition, Guillain-Barré Syndrome, a disorder that leads to muscle weakness or even temporary paralysis.

• If you are a pregnant woman, the virus can be devastating for your developing  fetus. In addition to increasing the risk of miscarriage, Zika can also cause microcephaly, a condition that causes the child to be born with a smaller head and brain.

• The disease has its roots in Africa, where it was first discovered in a monkey in the Zika forest in Uganda in 1947.

• The virus can sometimes reach the nervous system via the bloodstream.

• It can be transmitted by sexual contact. It can also be transmitted to infants when they are born.

• Bug repellant, long sleeves and pants and staying indoors are good ways to avoid the infection.

What we don’t know

• The virus  appears to increase the risk for a miscarriage, though researchers are not certain why as of yet.

• We do not know if there is a "safe" period during pregnancy when a mother could be infected and the child not suffer birth defects. Some scientist believe infection in the first trimester leads to microcephaly.

• We don't know if there is a link  to any other disease beside Guillain-Barré Syndrome.

• We don't know the extent of the disease. Since symptoms are mild, many don't know they have been infected.