Anika Begay
In May 2023, the World Health Organization issued a statement declaring the end of mpox, formerly known as monkeypox, a public health emergency. A little over a year later, the agency was forced to backtrack, with a much more serious outbreak spreading across much of sub-Saharan Africa.
Statistics show that since January, more than 15,000 cases of mpox and 461 deaths have been reported on the African continent, with the spread from countries such as the Democratic Republic of Congo (DRC), where mpox has long been endemic, to 13 other African nations: countries such as Rwanda, Kenya, Burundi and Uganda, where the disease had never previously had an impact.
In the eyes of scientists like Boghuma Titanji, an associate professor of infectious diseases at Emory University who studies Mpox outbreaks, this new, deadlier outbreak is the consequence of global health regulators failing to do enough last time.
It was the summer of 2022 when the outbreak of mpox first set off alarm bells. Suddenly, a virus that had always been mostly contained to parts of West and Central Africa was suddenly going global. Between early 2022 and December 2023, there were 92,783 confirmed cases of mpox in 116 countries, resulting in 171 deaths.
Despite those numbers, its perception as a public health threat quickly faded. “Ninety-five percent of cases in the 2022 outbreak were in men who have sex with men, who reported exposure through sexual or close contact with another infected person,” Titanji says. “It was a very targeted outbreak, which allowed vaccinations to be prioritized in that network.”
Countries in the Global North have been quick to successfully quell the outbreak within their own borders. Meanwhile, Titanji says, ramping up viral surveillance among African nations that had been battling a steady rise in mpox cases for the past four decades has quickly slipped to the bottom of the priority list, allowing a potentially more problematic variant to emerge undetected.
Mpox exists in two main subtypes, clade 1 and clade 2. Of these, clade 1 is thought to be up to 10 times more deadly, especially among population groups with weakened or developing immune systems, such as children younger than 5, pregnant women, and people who are immunosuppressed. This is the viral strain behind this new outbreak, and why infectious disease scientists are so alarmed. (Another outbreak spreading in South Africa among people with HIV is thought to be related to clade 2.)
“The 2022 global outbreak was clade 2, and the mortality was less than 1 percent,” says Jean Nachega, a Congolese infectious disease physician and associate professor of medicine at the University of Pittsburgh. “Now we’re talking about a strain that can have a mortality rate of up to 10 percent.”
While the previous outbreak primarily affected homosexual populations, data suggest the new strain is also spreading much more widely, perhaps first through sexual networks and then passing to family members. Last month, Nachega and others published a paper in the journal Nature Medicine showing how an outbreak of mpox began in the small mining town of Kamituga in eastern DRC through sex workers before spreading to neighboring Rwanda, Uganda, and Burundi when infected individuals returned home to visit their families.
