Global emergency declared over Zika virus
Rapid spread, soaring number of babies with birth defects prompt ‘extraordinary response’ from UN
The World Health Organization has declared a global health emergency over an outbreak of birth defects and neurological disorders linked to the fast-spreading Zika epidemic — a move that reflects the extraordinary circumstances surrounding a virus that causes no symptoms in the vast majority of cases. Monday’s announcement marks the fourth time the UN health agency has declared a “public health emergency of international concern” since it introduced the procedure in 2007, with previous declarations for H1N1, polio, and Ebola.
This is the first time a mosquito-borne virus has prompted the WHO to convene an emergency meeting — and the first time a public health emergency has been declared over clusters of neurological disorders with no proven link.
“The rapid spread of Zika and the alarming number of babies with microcephaly puts us in uncharted territory,” Peter Horby, a professor of emerging infections diseases and global health with the University of Oxford, said in a statement. “It’s an extraordinary situation that demands an extraordinary response.”
Such emergency declarations are meant as an international SOS signal and usually trigger increased money and efforts to halt the outbreak, as well as prompting research into possible treatments and vaccines. There are currently no licensed treatments or vaccines for Zika.
The Zika virus was first discovered in Uganda in 1947. It is primarily spread by the Aedes aegypti, a dayb-iting mosquito that is found in every country in the Americas except Canada and continental Chile.
For decades, experts thought Zika caused only mild disease, including fever, joint pain and rash, with 80 per cent of infected people showing no symptoms. But since exploding across the Americas — the virus has spread to 24 countries and territories in less than a year — Zika has been associated with an alarming surge in neurological disorders, especially microcephaly, a condition where babies are born with abnormally small heads and brains.
Zika has also been linked to Guillain-Barré syndrome, a potentially fatal autoimmune disorder that can cause temporary paralysis, with increases reported in Brazil, El Salvador and French Polynesia, which experienced a Zika outbreak in 2013 and 2014. Proving that Zika is directly causing either Guillain-Barré or microcephaly is a task that could take months or even years, however.
Officials aren’t even sure that the surge in these conditions is as dramatic as reports suggest; some suspect heightened awareness of Zika could account for part of the increase, with doctors perhaps finding more cases simply because they are looking harder.
Microcephaly is also a tricky condition to diagnose. In Brazil, more than 4,000 cases are under investigation but so far only 270 have been confirmed. A further 462 cases have been discarded as false diagnoses.
Another oddity is that Brazil is the only country in this current outbreak to report a surge in microcephaly (though the birth defect was also seen in smaller numbers during the French Polynesia outbreak).
These are all mysteries that the WHO and its emergency committee, comprised of 18 global experts, are hoping to answer.
“The experts agreed that a causal relationship between Zika infection during pregnancy and microcephaly is strongly suspected, though not yet
“WHO didn’t say what strategy it would have, what policy it would have on the ground, and what funding it would provide . . . all of those things are needed.” LAWRENCE GOSTIN GLOBAL HEALTH LAW EXPERT
scientifically proven,” WHO director general Dr. Margaret Chan said on Monday. “All agreed on the urgent need to co-ordinate international efforts to investigate and understand this relationship better.”
For Lawrence Gostin, an expert in global health law with Georgetown University, the WHO’s emergency declaration was welcome, but lacked specific guidance for countries affected by the epidemic.
“My major worry is that action has to speak louder than words,” said Gostin, who last week called on the WHO to call an emergency meeting on Zika. “WHO didn’t say what strategy it would have, what policy it would have on the ground, and what funding it would provide . . . all of those things are needed.”
Gostin also wondered if the emergency declaration will sow more confusion than clarity for the general public. Some countries, including Canada and the United States, have advised pregnant women (or those who plan on becoming pregnant) against travelling to Zika-affected regions, but the WHO did not echo these warnings Monday.
The UN agency said there was “no public health justification” to restrict trade or travel.
Gostin also said an emergency declaration pegged to microcephaly and Guillain-Barré — rather than the Zika virus itself — may perplex people further. “I wish that Dr. Chan had just declared it for the Zika epidemic, which has explosive pandemic potential (and) is in more than 20 countries,” he said.
The WHO said many studies are investigating a causal link between the virus and the neurological conditions, with several others soon to be launched. Urgent efforts to produce a vaccine are also underway, though it will likely be years before a Zika vaccine is widely available.
While the WHO has reacted to Zika far more quickly than it did for Ebola (a crisis for which the UN health agency attracted heavy criticism), some question why any emergency declaration is needed before the world does what it takes to respond to outbreaks.
“We should be anticipating and getting ahead of infections,” said Dr. Ross Upshur, a University of Toronto professor who served on the WHO’s ethics committee for the Ebola outbreak.