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Monkeypox: What’s behind WHO’s decision not to declare a public health emergency?

BMJ 2022; 377 doi: (Published 29 June 2022) Cite this as: BMJ 2022;377:o1604
  1. Luke Taylor
  1. Bogotá

With cases rising globally, the decision not to classify the monkeypox outbreak as a public health emergency of international concern has raised eyebrows, as Luke Taylor reports

World Health Organization officials have said that the global spread of monkeypox does not yet merit declaring the outbreak a public health emergency of international concern (PHEIC).1

The decision, announced on 25 June, was made after two days of deliberation following a WHO emergency committee.

Some 3000 cases of monkeypox have now been identified in more than 50 countries since early May, according to WHO. The spread of the viral illness has caused alarm as many of those countries had not seen sustained transmission of monkeypox until this year.

Though WHO decided not to declare monkeypox a PHEIC—the highest level of alert the organisation can make—it “recognised that the convening of the committee itself reflects increasing concern about the international spread of monkeypox,” WHO’s director general Tedros Adhanom Ghebreyesus said. The organisation would review the decision if the outbreak grew in global reach or severity, he added.

Declining to classify the outbreak a PHEIC surprised some global health experts who said that WHO had seemed to conclude in its final report that monkeypox had met the three necessary criteria.2

What constitutes a PHEIC?

An outbreak is considered a PHEIC when it is extraordinary, of significant risk of international spread, and could require a coordinated response to get under control.

“It seems like the criteria for a PHEIC has been met but yet it hasn’t been declared,” said Clare Wenham, associate professor of global health policy at the London School of Economics. “There’s something else at play, we just don’t know what that thing is.”

The decision to label a health threat a PHEIC is made ultimately by an independent committee of experts who advise WHO. But Paul Hunter, professor in medicine at the University of East Anglia, said the organisation’s report left some hints as to why it may have decided not to escalate the threat level.

It may be because WHO concluded that transmission rates are falling in non-endemic countries, that declaring a PHEIC could cause stigmatisation and human rights violations in affected groups, or that the understanding of the public health risk of monkeypox remains too incomplete, Hunter said.

An uncomfortable admission?

Alexandra Phelan, global health lawyer at Georgetown University, said the decision not to classify monkeypox a PHEIC raised the question of whether the alternative would have been an uncomfortable admission that the perceived level of threat of an outbreak depended largely on how wealthy the nations affected are.

Monkeypox has been circulating in several African countries for decades but has only received international concern and media coverage after it spread to Europe and North America this year.

“It is unjust and unethical to determine an event is only extraordinary if it is now occurring in high income countries,” Phelan told Science.3

The sustained spread of monkeypox in many countries which had previously only seen isolated cases of the virus—often linked to travel from Africa or animal trafficking— has puzzled epidemiologists and virologists.

In the UK, which accounts for around a third of cases in the current global outbreak, 99% of cases have been reported in men and mostly in networks of men who have sex with men. Some outbreaks have been linked to individual “super spreader” events which may have fuelled an early surge in cases.4

A study led by researchers in Portugal and published in Nature Medicine found that the virus has acquired more mutations than expected. A mutation to the virus is one theory as to why it is spreading in new countries when it had previously fizzled out.56

Germany is currently seeing the most sustained growth in monkeypox virus transmission rates in Europe, with the country now reporting nearly 50 new infections a day.7

In England, where most infections of the UK’s monkeypox cases have been detected, 1035 cases were reported to 26 June, 162 more than two days previously.8

Increasing transmission in the UK

Hunter noted that while the rapid growth in cases in the UK has slowed since the initial outbreaks, transmission has increased in the past two weeks. “This does suggest that existing control strategies of contact tracing and ring vaccination will not be sufficient to bring the epidemic under control and the wider vaccination strategy to be implemented in the UK will be needed,” he said.

He added that a PHEIC declaration may have helped to increase vaccine manufacture and support African countries affected, though it would not prevent countries from taking the necessary action to get the virus under control.

In theory, a PHEIC declaration obligates WHO member nations to follow its health recommendations. Polio and covid-19 are both currently deemed by WHO to be PHEIC.

“Governments do not need to wait for an official declaration to begin acting in a coordinated and measured way,” said Gordon Dougan, director of infectious diseases at Wellcome. “Where cases have been identified, rapid public health responses such as enhanced disease surveillance, contact tracing, and self-isolation will be crucial. But with the virus continuing to spread, all countries must step up, integrate their preparations, and help those with limited capability.”

“I suspect that over the next two weeks we shall see the overall epidemic outside of Africa continue to grow and possibly accelerate and a PHEIC declared sometime in the next few weeks,” Hunter said.

Meanwhile,9 European Union countries with the highest rates of infections began to receive their first doses of a smallpox vaccine this week. Spain—which has the next highest number of recorded cases globally after the UK—will take delivery of 5300 doses of Bavarian Nordic’s Imvanex vaccine on 28 June, with Belgium, Germany, and Portugal to follow.

Action has also been taken in the US. The White House announced on 28 June that it will begin sending out tens of thousands of vaccine doses to clinics across the country in an effort to control the outbreak. As of 29 November, there have been 306 cases and no deaths recorded in the US.