The World Health Organization declared the spread of mpox in Africa a global health emergency on Wednesday.

The health agency warned that the virus might ultimately spill across borders.

What is mpox?

Mpox, also known as monkeypox, was first identified by scientists in 1958 when there were outbreaks of a “pox-like” disease in monkeys. Until recently, most human cases were seen in people in central and West Africa who had close contact with infected animals.

In 2022, the virus was confirmed to spread via sex for the first time and triggered outbreaks in more than 70 countries across the world that had not previously reported mpox.

Mpox belongs to the same family of viruses as smallpox but causes milder symptoms like fever, chills and body aches. People with more serious cases can develop lesions on the face, hands, chest and genitals.

Digitally-colorized electron microscopic (EM) image depicting a monkeypox virion (virus particle), obtained from a clinical sample associated with a 2003 prairie dog outbreak, published June 6, 2022. (Smith Collection/Gado/Getty Images)

How many deaths have been reported?

WHO said there have been more than 14,000 cases and 524 deaths in Africa this year due to mpox, which exceeds last year’s figures.

Are there cases in the US?

So far, more than 96% of all cases and deaths are in a single country in Africa – Congo.

Scientists are concerned by the spread of a new version of the virus that might be more easily transmitted among people.

What’s different about the current outbreak in Africa compared to the 2022 epidemic?

During the global outbreak of mpox in 2022, gay and bisexual men made up the vast majority of cases and the virus was mostly spread through close contact, including sex.

Although some similar patterns have been seen in Africa, children under 15 now account for more than 70% of the mpox cases and 85% of deaths in Congo.

Ahead of its emergency meeting, Tedros said officials were dealing with several mpox outbreaks in various countries with “different modes of transmission and different levels of risk.”

“Stopping these outbreaks will require a tailored and comprehensive response,” he said.

Greg Ramm, Save the Children’s Congo director, said the organization was particularly worried about the spread of mpox in the crowded camps for refugees in the east, noting there were 345,000 children “crammed into tents in unsanitary conditions.” He said the country’s health system was already “collapsing” under the strain of malnutrition, measles and cholera.

Dr. Boghuma Titanji, an infectious diseases expert at Emory University, said it was unclear why children were so disproportionately hit by mpox in Congo. She said it might be because kids are more susceptible to the virus or that social factors, like overcrowding and exposure to parents who caught the disease, might explain it.