Update:  Reports say that the Zika virus outbreak in Brazil may have something to do with a type of mosquito that has been genetically modified.  The mosquito was released to the environment to eradicate the wild mosquitoes that carry illness-causing viruses.  Also cases reported indicate that Zika virus can be transmitted through sex.  For the reason, travelers are urged to use condoms or avoid having sex.

What is Zika virus and how is it spread?

Zika virus is a virus that is spread through the bites of daytime-active Aedes mosquitoes.  Other animals and infects may also transmit the virus.

What is the illness Zika virus causes?

The virus can cause a mild illness known as Zika fever in humans with common symptoms including fever, rash, joint pain and red eyes. In most cases, the illness disappear in less than a week.

However, Zika virus infection is highly dangerous to pregnant women.  The virus can damage the fetal brain.  It has been reported that pregnant women infected with this virus in Brazil gave birth to babies with birth defects and poor pregnancy outcomes. (Update on Feb 6, 2016:  New reports say that no evidence indicates that this virus actually cause the birth defect called microcephaly. Washington posted reported that in Colombia alone, 3177 pregnant women have been diganosed with Zika virus but there is no evidence to suggest that the virus causes the birth defect.  In Colombia, 25,600 people have been infected with this virus). 

How many cases of Zika virus are reported every year in the United States?

Zika virus infection is extremely rare.   Fewer than 1,000 Americans are believed to get infected with Zika virus every year.  But people contract the virus while traveling in other countries.

How can Zika virus fever be treated?

A case of illness caused by Zika virus needs to be confirmed by lab tests or imaging diagnostic methods.  There is no medicine that can be used to cure the illness while some medications may be used to help relieve symptoms such as fever and pain to make patients feel better.  Luckily, the illness will be gone without treatment in less than one week in most cases.

Where has Zika virus been found?

According to the Centers for Disease Control and Prevention, Zika virus outbreaks have been reported in areas of Africa, Southeast Asia, and the Pacific Islands.

No locally transmitted case of Zika virus infections has been reported in the United States while cases have been reported among returning travelers.

For more information on zika virus, read on the website of the Centers for Disease Control and Prevention

(Edited by David Liu)