Global emergency declared over Zika virus

The World Health Organization declared Monday that explosive growth of the mosquito-borne Zika virus — which has been spreading rapidly in the Americas and may be linked to birth defects — constitutes an international public health emergency, signaling an new phase in the global effort to battle the virus.

The declaration was a rare move that signals the seriousness of the outbreak and gives countries powerful new tools to fight it.

The United Nations health agency made the decision after convening an panel of experts in Geneva amid reports from Brazil linking the virus to microcephaly, a birth defect of the brain in which babies are born with abnormally small heads.

The recent “cluster” of microcephaly cases and other neurological disorders reported in Brazil followed a similar “cluster” in French Polynesia in 2014, World Health Organization director-general Margaret Chan said in a statement.

Last week, the U.N. health agency had declared a threat of “alarming proportions,” warning that the Zika virus was “spreading explosively” across the Americas.

The current outbreak of Zika has taken the world by surprise. It was first identified in 1947 in Uganda, and for years lived mostly in monkeys. But in May in Brazil, cases began increasing drastically. The U.N. health agency has estimated that 4 million people could be infected by the end of the year.

It is spreading fast in the Americas because people there have not developed immunity.

The health agency has declared a public health emergency three times since 2007, when it first established the procedure. The declarations were for the influenza panademic in 2009; in 2014, when polio seemed resurgent; and in August 2014 for Ebola.

Some experts applauded the decision to add Zika to the list.

“This should be a global wake-up call,” said Lawrence O. Gostin, director of the O’Neill Institute for National and Global Health Law at Georgetown University.

But he added: “The main question on my mind is whether they will back up their words with decisive action.”

Zika’s rapid rise and the specter of associated birth defects have major implications in a warm region with struggling economies and vast flows of tourists. Brazil is preparing to hold the Olympics this summer, and Zika is complicating those plans. The U.S. Centers for Disease Control and Prevention has advised pregnant Americans to avoid travel to the region.

Still, U.S. officials have taken pains to underscore that the virus does not pose a major threat to the United States, where mosquito control efforts are robust and effective.

Despite Monday’s declaration, the U.N. health agency did not move to restrict travel or trade in regions where the virus is found.

It will likely trigger additional resources being put toward researching the virus and preventing its spread; to date, officials say, the only cases of Zika diagnosed in the United States involve people who are believed to have contracted it while traveling abroad.

“It is important to understand, there are several measures pregnant women can take,” Chan said. “If you can delay travel and it does not affect your other family commitments, it is something to consider.”

“If they need to travel, they can get advice from their physician and take personal protective measures, like wearing long sleeves and shirts and pants and using mosquito repellent.”

The U.N. health agency, however, says transmission will probably spread to all the countries and territories in the Americas hosting the mosquito that transmits the virus — known as the Aedes mosquito — including the U.S. mainland.

Some reports have also linked the Zika virus to cases of Guillain-Barre syndrome, or GBS, which can cause temporary paralysis.

Among other recommendations, the committee of experts convened by the world health body suggested that surveillance for microcephaly and Guillain-Barre syndrome “should be standardized and enhanced, particularly in areas of known Zika virus transmission and areas at risk of such transmission.” The panel also urged additional research into clusters of microcephaly and other disorders linked to Zika.

“As these clusters have occurred in areas newly infected with Zika virus, and in keeping with good public health practice and the absence of another explanation for these clusters, the committee highlights the importance of aggressive measures to reduce infection with Zika virus, particularly among pregnant women and women of childbearing age,” the panel said.

The illness from the Zika virus is not considered serious, and symptoms — including rashes, joint pain and reddened eyes — are usually mild and last for several days or a week, experts say. But the reports of links to birth defects from Brazil have triggered alarm. There is no vaccine for the virus.

The Zika illness is common in parts of equatorial Africa and Southeast Asia. Outbreaks have also been reported in the Pacific islands.

But the disease did not begin to spread widely in the Americas until May, when an outbreak was reported in Brazil. It has since spread to 23 countries and territories in the region.

In Brazil, where Zika has taken on the character of a national emergency, health authorities said they plan to deploy 220,000 members of the military on a single day this month to distribute pamphlets across the country to educate people about the risks posed by mosquitoes.

The government of El Salvador, meanwhile, has advised people to put off having children for two years because of the threat.

Residents in Brazil and other affected have also been urged to clean up stagnant pools of water and containers in which the mosquitos tend to breed.

Containers that can hold even small amounts of water — buckets, flowerpots, tires — should be emptied, cleaned or covered to prevent mosquitoes from breeding in them, health authorities say.

Experts say knowledge of the link between the Zika virus and birth defects is evolving and not yet confirmed. But the reported links from Brazil were sufficient to declare an emergency, officials said.

Brazil President Dilma Rousseff has issued a decree allowing public officials to enter abandoned or empty homes by force if necessary, in the absence of persons authorized to permit entry.

The measure is part of the country’s efforts to eradicate the breeding grounds of the Aedes aegypti mosquito, which has also been identified as a carrier of dengue fever, chikungunya, and yellow fever.

Brazil’s efforts to target the mosquito’s breeding grounds are mainly focused in the northeastern Brazilian states of Bahia, Pernambuco and Paraiba, whose governors attended a teleconference meeting with the president Friday, also accompanied by the governors of Rio de Janeiro and Sao Paulo states.

At a news conference following the meeting, Rousseff admitted that Brazil was “losing the fight against Aedes,” but vowed that it would not lose the war. Rousseff said there could be “no contingencies or limits” to the resources the government would make available in the fight against Zika.

The World Health Organization, which was widely criticized for its sluggish response to the 2014 Ebola crisis in West Africa, has been eager to show its responsiveness this time. Despite dire warnings that Ebola was out of control in mid-2014, the agency didn’t declare an emergency until months later, after nearly 1,000 people had died.

“If indeed, the scientific linkage between Zika and microcephaly is established, can you imagine if we do not do all this work now and wait until the scientific evidence comes out?” Chan said. “Then people will say, ‘Why didn’t you take action?’ ”

The World Health Organization “took a very serious hit to their reputation” in the Ebola crisis, said Ron Waldman, a professor of global health at the Milken School of Public Health at George Washington University.

Zika and Ebola are very different. Ebola was incredibly deadly, and it spread through contact with bodily fluids. Zika is not known to be fatal, and it has mild symptoms for most people.

Michael Osterholm, an infectious diseases expert at the University of Minnesota, said that it was still unclear how Zika had evolved since it first emerged in Africa, but that even minor genetic changes might have major consequences.

“It could have just been some point mutation (in the virus) that has now made a big difference,” Osterholm said, adding it would likely take years to curb the mosquito populations capable of spreading Zika — and before local populations gain enough immunity for the number of cases to fall.

Jimmy Whitworth, an infectious diseases expert at the London School of Hygiene and Tropical Medicine, said doctors might soon see babies born elsewhere with malformed heads as the virus becomes entrenched in other countries.

“It could be that we’re getting the strongest signal in Brazil,” he said. “But having these cases occurring and pinning it to Zika is tough.”

Whitworth said it was important for the World Health Organization to act quickly, despite the lack of definitive evidence that Zika is responsible for the surge in microcephaly cases.

“For situations like this, you have to essentially have a ‘no regrets’ policy,” he said. “Maybe this will be a false alarm when more information is available months later, but it’s serious enough on the evidence we have right now that we have to act.”

Although the Aedes aegypti mosquito is the focus of the Zika efforts, another mosquito — Aedes albopictus — also has the potential to transmit the virus.

This story was originally published February 1, 2016 at 6:57 PM with the headline "Global emergency declared over Zika virus."