GENEVA, Switzerland, Feb. 1 (UPI) -- The World Health Organization on Monday sounded an alarm over the recent outbreak of the Zika virus, calling the spread an international health emergency.
The Zika is transmitted by mosquitoes and has spread into more than 20 countries in Latin America over the last nine months.
By declaring the rare emergency, the W.H.O. allows nations impacted by the outbreak to fight it with powerful new tools and resources.
The primary concern among health officials is that the Zika virus might be linked to microcephaly -- a neurodevelopmental disorder in newborns that is accompanied by brain damage and failure of the babies' heads to grow to the proper size.
CDC Director Dr. Tom Frieden said in a contributing story for CNN that two groups are at greatest risk of contracting the virus -- residents in Caribbean and Central American nations and territories and pregnant women.
"In these areas, women who are pregnant need to protect themselves from mosquito bites by using repellants, permethrin-coated clothing, long sleeves and pants, and by staying indoors (ideally in places with air conditioning) as much as is practical," Frieden wrote. "We advise pregnant women to postpone travel to areas where Zika is spreading."
"Last year, the virus was detected in the Americas, where it is now spreading explosively," WHO director Margaret Chan said last week. "Cases have been reported in 23 countries and territories in the region. The level of alarm is extremely high."
"The spread of the virus through blood transfusion and sexual contact have been reported in isolated cases. However, for most of the nonpregnant population, there is no reason to think Zika presents a particular risk," Frieden added.
The mosquito-borne virus was discovered in the Zika forest of Uganda in 1947, and mostly has affected monkeys. Although there have been small outbreaks of the virus in humans, including one in the Pacific Islands in 2007, it has posed little threat to humans and was considered a mild concern.
Stephen Feller contributed to this report