The World Health Organisation (WHO) has reported that the mosquito-transmitted Zika virus is spreading explosively and could infect as many as three to four million people in the Americas.
The virus is mainly linked to severe birth defects in thousands of babies in Brazil and has dramatically increased.
The WHO has called for an emergency meeting to help determine its response, as well as an observed rise in neurological disorders and neonatal malformations.
Initially, Brazil reported its first case of Zika virus disease in May last year and since then, the disease has spread within the country and to 22 other countries and territories in the region.
WHO director-general Margaret Chan said: "The level of alarm is extremely high and for decades the disease, transmitted by the Aedes genus of mosquito, ‘slumbered,’ affecting mainly monkeys and occasionally causing a mild disease of low concern in humans.
"The situation today is dramatically different. Last year, the virus was detected in the Americas, where it is now spreading explosively. As of today, cases have been reported in 23 countries and territories in the region."
WHO’s Pan American Health Organisation (PAHO) Department of Communicable Diseases and Health Analysis director Marcos Espinal said that the virus is expected to spread to other parts of the world where dengue, spread by the same mosquito, is also present.
Currently, the virus is linked to about 4,000 births of babies with abnormally small heads, a condition known as microcephaly.
Dr Chan further noted: "We need to get some answers quickly. I am asking the Committee for advice on the appropriate level of international concern and for recommended measures that should be undertaken in affected countries and elsewhere.
"I will also ask the Committee to prioritise areas where research is most urgently needed.
"The possible links, only recently suspected, have rapidly changed the risk profile of Zika, from a mild threat to one of alarming proportions.
"The increased incidence of microcephaly is particularly alarming, as it places a heart-breaking burden on families and communities. WHO is deeply concerned about this rapidly evolving situation."
Earlier this month, the Virginia Department of Health (VDH) has confirmed that a resident of Virginia, who travelled outside the US, has tested positive for the mosquito-transmitted Zika virus.
Recently, the adult had travelled to a country where Zika virus was widespread and the infection was confirmed through testing by the US Centers for Disease Control and Prevention (CDC).
Currently, the VDH is alerting the public of the potential for contracting Zika virus while travelling abroad.
Image: PAHO director Dr Carissa Etienne and WHO Director-General Dr Margaret Chan at WHO Executive Board meeting on Zika virus situation. Photo: courtesy of WHO/C. Black.