WHO declares end to mpox emergency, though scientists warn of potential for 'resurgence'

After the World Health Organization (WHO) opted to end COVID-19's designation as a global public health emergency last week, the organization declared an end to another emergency on Thursday: mpox, the painful, potentially deadly disease formerly known as monkeypox.

A separate group of scientists for the health agency signalled that the global outbreak is now under control.

But while mpox may have faded from the headlines — and from public consciousness — experts say there's still cause for concern if countries scale back surveillance and vaccination efforts at a time when the virus remains in global circulation.

"When case counts started declining, especially in the global north, people gradually became disinterested in the outbreak," said physician-scientist Dr. Dimie Ogoina, a professor of medicine at Niger Delta University, who was among the first clinicians to raise alarms about the sudden, unusual spread of mpox in Nigeria six years ago, before it exploded globally.

"And the fear is that we are reverting back to where we were 50 years ago."

Turning off the spotlight on this virus may leave the world vulnerable to a "resurgence," particularly as more people travel through the spring and summer, warned Ogoina, who is also involved in the WHO's emergency committee on mpox.

Before the committee's Wednesday decision, he told CBC News he personally felt it would be premature to end the emergency declaration, despite a global drop in cases.

"What happened [last] May to July can repeat itself," he warned.

WATCH | What it's like to recover from mpox:

100+ countries experienced cases

There have been 87,000 known infections and 140 deaths reported from more than 100 countries — largely through sexual networks, and primarily impacting men who have sex with men — since mpox first developed a foothold outside its endemic regions of Africa last summer.

That spike in cases was short-lived and tapered off last fall, and there were 90 per cent fewer cases reported in the last three months compared to the three months before, WHO data shows.

"Due to global mobilization and the rapid response of most countries, we now see steady progress in controlling this outbreak," said WHO director general Dr. Tedros Adhanom Ghebreyesus in video remarks on Wednesday.

But those gains haven't been felt equally.

Only sporadic infections are now being reported here in Canada and in the U.S., following vaccination campaigns geared toward higher-risk individuals. Yet the mpox virus continues to transmit in other areas, such as the Western Pacific region, along with a simmering outbreak involving thousands of cases in Mexico that is prompting concerns over possible underreporting of infections and deaths.

Dr. Jorge Saavedra, executive director of the AHF Global Public Health Institute at the University of Miami, said a lot of cases likely went undiagnosed in Mexico last year.

"The worst part," he said, "is they have not authorized the vaccine."

There's also a lack of access to vaccines and therapeutics in Nigeria and other African countries, even though the continent has been dealing with mpox for longer, Ogoina noted.

Tedros also said there's "no clear trend" for cases in that region.

Ogoina said WHO's figures are actually hard to parse. Looking at data reported throughout Africa, he said it appears that many countries aren't reporting cases.

"It's not because we don't have cases," he said, "but it's because of a lack of capacity."

'Still uncertainties' about how mpox will evolve

That lack of surveillance makes it difficult to know the true scope of mpox's spread throughout the entire continent, and should other countries follow suit as interest in the global outbreak wanes, Ogoina is concerned more regions will be "walking blindly," not knowing the full burden of disease.

University of Manitoba microbiologist Jason Kindrachuk, who is currently part of an mpox research team working between Canada and Africa, agreed the situation may be growing murkier.

"So if we see a travel-related case in the summer, somewhere in Canada, it can realistically be from anywhere in the world where we've seen circulation — because we don't really have a good idea of what areas have cryptic transmission or ongoing transmission that's not being recognized," he said.

All the while, the virus continues to evolve. Decades ago, once it was established that mpox could spread to humans, it was restricted to rural settings, often impacted children and was mostly acquired through contact with animals, Ogoina said.

WATCH | Sorting fact from fiction on how mpox spreads:

He outlined its trajectory since then: Next came hospital infections, then the discovery of a deadlier strain, then Nigeria's 2017 outbreak involving younger men, then its global explosion among sexual networks in 2022, coupled with a growing understanding that the disease can have a more severe presentation among individuals co-infected with HIV.

How will it change next?

"There are still uncertainties," Ogoina said.

At some point down the line, the virus could move into additional niches in the global population, Kindrachuk said, "like we've seen in Africa for decades, with women and children being included."

He said that while the current outbreak was curtailed, thanks to a combination of vaccination programs and community efforts to clamp down on chains of transmission, the virus hasn't disappeared.

"And until we're able to control [mpox] circulation at the source, where it's endemic, we need to appreciate that even if we get it eliminated from different countries across the globe where it's been introduced, there is still that risk that we can see other [strains] or reintroductions," he said.