WHO warns Zika virus could affect four million people

WHO Director-General Margaret Chan said the spread of the virus had gone from a mild threat to one of alarming proportions.

Chan is due to convene an international health regulations emergency committee on the virus on 1 February in Geneva, Switzerland, to decide whether it should be declared a public health emergency of international concern.

The Zika virus is spread to people through mosquito bites. It is generally mild and self-limiting, lasting two to seven days.

The symptoms of the virus include fever, rash, joint pain, itching, conjunctivitis or red eyes, headache, muscle pain, and eye pain.

The virus was initially isolated in 1947 from a monkey in the Zika forest of Uganda. In humans, the virus occasionally resulted in a mild disease of low concern.

Since last spring, the virus has spread to 23 countries and territories, mostly in the Americas.

Recently, a Virginia resident who traveled outside the US has tested positive for the virus. The infection was confirmed through laboratory testing by the US Centers for Disease Control and Prevention (CDC).

Several governments such as the UK and the US have advised pregnant women to consider delaying travel to countries with ongoing Zika virus outbreaks.

Other governments or health agencies have also issued similar travel warnings.

Image: Aedes aegypti – a mosquito vector of Zika virus. Photo: courtesy of Rafaelgilo.