The WHO Just Declared That the Zika Virus Is an International Health Emergency

The World Health Organization on Monday declared the mosquito-borne Zika virus to be an international public health emergency as the disease, which evidence suggests could be linked to thousands of birth abnormalities in Brazil, spreads rapidly.

WHO Director-General Margaret Chan told reporters an international coordinated response was needed, although restrictions on travel or trade were not necessary.

The emergency designation was recommended by a committee of independent experts to the United Nations agency following criticism of a hesitant response so far. The move should help fast-track international action and research priorities.

Related: Here's What You Should Know About the Zika Virus

The WHO said last week the Zika virus was "spreading explosively" and could infect as many as 4 million people in the Americas.

The agency was criticised for reacting too slowly to the Ebola epidemic in West Africa which killed more than 10,000 people, and has promised to do better in future global health crises.

The WHO's International Health Regulations emergency committee brings together experts in epidemiology, public health, and infectious diseases from the Americas, Europe, Asia, and Africa.

Since October Brazil has reported nearly 4,000 suspected cases of microcephaly, in which infants are born with smaller-than-usual brains. The health ministry has said that this is multiple times the number of cases of the condition reported in previous years, and suggested there could be a link with Zika. There is still no clear scientific proof of the connection.

Brazilian Health Minister Marcelo Castro told Reuters that the epidemic of the virus was worse than believed because in 80 percent of the cases the infected people have no symptoms.

As the virus spreads from Brazil, experts are expecting to see other countries in the Americas begin to report cases of babies born with potentially Zika-linked abnormalities.

The Pan American Health Organization says that Zika has now spread in 24 nations and territories in the Americas.

Related: Latin America Responds to the Zika Virus With Soldiers, Repellent, and Pregnancy Warnings

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