Intended for healthcare professionals


Monkeypox: WHO declares a public health emergency of international concern

BMJ 2022; 378 doi: (Published 26 July 2022) Cite this as: BMJ 2022;378:o1874
  1. Luke Taylor
  1. Portsmouth

The World Health Organization has declared the global monkeypox outbreak a public health emergency of international concern (PHEIC) as public health measures taken fail to stem the disease’s spread.

A PHEIC is the highest level of alert that the UN health body can give and has been previously attributed to covid-19, polio, the 2014 outbreak of Ebola, and the spread of the Zika virus in 2016.

Global health experts hope the decision will spark a more coordinated international response, further research into the disease, and the ramping up of vaccine production.

WHO director general Tedros Adhanom Ghebreyesus told journalists on 24 July that he made the final call after opinions at an International Health Regulations Emergency Committee meeting on Thursday were evenly split between those who believed monkeypox constituted a PHEIC and those who did not.

Tedros told journalists, “We have an outbreak that has spread around the world rapidly, through new modes of transmission, about which we understand too little, and which meets the criteria in the international health regulations. For these reasons, I have decided that the global monkeypox outbreak represents a public health emergency of international concern.”

The emergency committee had convened a month earlier and concluded that the viral disease did not merit declaring a PHEIC. The decision confused public health experts, who said the committee appeared to conclude that it had met the necessary criteria to escalate the threat level.1

The spread of the disease has accelerated since the first emergency committee convened and appears to have driven the reversal of their previous judgement. As of 25 June, 3000 cases of monkeypox had been reported to WHO from 47 countries—but by 23 July that number had increased to more than 16 000 cases from 75 countries and territories, causing five deaths.

“WHO’s assessment is that the risk of monkeypox is moderate globally and in all regions, except in the European region where we assess the risk as high,” Tedros said. “There is also a clear risk of further international spread, although the risk of interference with international traffic remains low for the moment.”

Monkeypox has been endemic in west Africa for decades, where the illness is usually spread to people by infected wild animals. Until 2022 infections reported in Europe and North America were usually isolated cases linked to travel from Africa or animal trafficking.

This year the monkeypox virus, which is closely related to smallpox and produces similar symptoms, has spread to many countries which had never before reported cases and where the disease is now sustaining itself through human-to-human transmission.

Some 70% of cases this year were reported in America and 15% in Europe, WHO data show.

“The rate of spread of monkeypox has not slowed, and public health strategies have not shown a high rate of success,” said Hugh Adler at the Liverpool School of Tropical Medicine.2 The disease is “presenting in atypical ways,” making contact tracing difficult, he added.

Four sets of recommendations

WHO officials have now drafted four sets of recommendations that countries should follow depending on their level of transmission.

Countries with recently imported cases of monkeypox and those that are seeing human-to-human transmission are being asked to implement a coordinated response to stop transmission and protect vulnerable groups, increase public health surveillance and measures, and strengthen clinical management and infection prevention and control in hospitals and clinics.

WHO will also work with civil society organisations to reduce stigma around the disease, which can deter people from accessing health services.

WHO officials stressed that despite monkeypox meriting the highest level of concern, its epidemiological profile meant that it was not too late for countries to contain it.

So far, 98% of infections have been reported in men who have sex with men (MSM) and especially in those with multiple sexual partners. “That means that this is an outbreak that can be stopped with the right strategies in the right groups,” Tedros said.

The disease has various modes of transmission, including skin-to-skin contact, kissing, and the touching of infected materials.

The UK Health Security Agency lowered its threat level of monkeypox on 5 July as it said it had not spread beyond MSM, was not spreading easily, and rarely causing severe illness.3


WHO is also recommending that countries accelerate research into the use of vaccines, therapeutics, and other tools to combat monkeypox.

Piero Olliaro, professor of infectious diseases of poverty at the University of Oxford, said a lack of trial data on effectiveness and high prices have led to “very limited” supplies of drugs and vaccines.

Scaling up the production of monkeypox vaccines and ensuring that low and middle income countries have access to them must be a main goal if the outbreaks are to be contained, say global health experts.

WHO previously announced that it was drawing up a vaccine sharing mechanism for the most affected countries but few details on the scheme have emerged.

How quickly countries can deploy vaccines and other measures to contain monkeypox depends on “how relevant and weighty a WHO declaration is perceived by governments, public bodies, and vaccine manufacturers and suppliers, as well as people at risk of monkeypox around the world,” Adler said.2

Boghuma Kabisen Titanji, assistant professor of medicine at Emory University in Atlanta, said countries must act quickly and robustly to tackle the disease before it establishes itself in the human population. “The PHEIC is the first step and there is a lot of work that needs to be done,” she said.

Tedros announced that WHO member states are now considering whether they should improve the international health regulations and in particular the process for declaring a public health emergency of international concern.