Update: The Centers for Disease Control and Prevention has definitively confirmed the link between the Zika virus and microcephaly, as well as other serious birth defects. CDC scientists published their findings in the New England Journal of Medicine.
"This study marks a turning point in the Zika outbreak. It is now clear that the virus causes microcephaly. We are also launching further studies to determine whether children who have microcephaly born to mothers infected by the Zika virus is the tip of the iceberg of what we could see in damaging effects on the brain and other developmental problems," said Thomas R. Frieden, MD, director of the CDC.
This story was originally published on February 1, 2016.
The World Health Organization has declared the Zika virus a global public health emergency, calling the outbreak and its possible link to birth defects in the Americas an "extraordinary event.
The World Health Organization has declared the Zika virus a global public health emergency, calling the outbreak and its possible link to birth defects in the Americas an "extraordinary event.
Concerns that the mosquito-borne illness may be responsible for a reported increase in babies born with microcephaly have triggered widespread alarm. The Centers for Disease Control and Prevention has recommended that pregnant women delay travel to countries where transmissions of the virus have been reported, and governments in some countries hit hard by the outbreak have gone as far as encouraging women to hold off on getting pregnant.
The head of the WHO has warned that the virus is "spreading explosively" and could infect between 3 and 4 million people across the Americas in the next year. While the mosquito that carries the illness can be found in parts of the United States, no cases of people contracting Zika in the U.S. have been reported so far — all cases currently being treated here are among people who were infected while traveling abroad.
Monday's decision to declare the emergency came during a crisis conference of independent experts, the Associated Press reported. The declaration could lead to more money for response and research, according to the AP. The head of the WHO said an immediate, coordinated response is needed to address the virus.
"I am now declaring that the recent cluster of microcephaly and other neurological abnormalities reported in Latin America following a similar cluster in French Polynesia in 2014 constitutes a public health emergency of international concern," WHO Director-General Margaret Chan said Monday, according to the BBC.
The last virus to trigger such an emergency was the 2014 Ebola outbreak, the AP notes. More than 11,000 people died — and more than 28,000 were sickened — during the months that the epidemic ravaged West Africa.
For more on the Zika virus, check out this explainer from our colleagues at Refinery29's Health & Wellness desk.