Mpox is an infection caused by the monkeypox virus, a zoonotic disease that causes a painful, bumpy rash. It can be spread through direct contact with infected animals or the body fluids of an infected person. The mpox virus started to become a worldwide problem in 2022, and is continuing to affect people in many countries, including the Democratic Republic of Congo (DRC). Scientists have been working to learn more about its spread and evolution. Since 2010, the virus has spread to affect almost every province of DRC, and while it once tended to infect people in rural areas, it now also infects people in urban settings. People had typically contracted the virus after contact with wildlife, but now the disease is mostly spreading from person to person.
This change has occurred with the emergence of a new type of mpox, called subclade Ib. This version is capable of sustained human-to-human transmission, and it has driven an increase in mpox cases among 15 to 34 year old individuals, particularly in the DRC province of South Kivu.
There, people with mpox had large number of skin and genital lesions, which indicated the the virus was likely related to sexual contact. The disease was not considered to be especially severe, however; there were two deaths among 403 individuals who had been hospitalized for the illness.
"The reality is that what we were seeing in South Kivu among those cases was actually different than what we've seen historically," said Dr. Jason Kindrachuk, the University of Manitoba Canada Research Chair in molecular pathogenesis of emerging viruses and associate professor of medical microbiology and infectious diseases at the Max Rady College of Medicine, Rady Faculty of Health Sciences.
Historically, there haven't been many mpox cases in the capital of DRC, Kinshasa. But this has changed too.
"The expansion of this virus is concerning. Viruses don't have passports. They don't respect international borders. We need to get things under control," noted Kindrachuk.
"It's concerning because our research that was published last week in The Lancet shows that it's spreading in Kinshasa. This becomes an even bigger predicament in terms of response efforts because you're not only dealing with spread across the majority of the country, but you also now have it embedded in this very large metropolis that is a major network for many other countries in Africa." About 17 million people live in Kinshasa.
A recent study reported in The New England Journal of Medicine has also found evidence of mpox transmission from three pregnant women to their fetuses, causing infection or the loss of the pregnancy.
Kindrachuk suggested that it will be important to make preventive interventions like vaccinations available to pregnant individuals, and learn more about the potential impact of mpox infection during pregnancy.
"For us, the complexity is increasing, but all the data that we are identifying in our studies helps inform our response and certainly the actions of other international individuals, organizations and the Congolese on the ground who are leading the response efforts."
Sources: University of Manitoba, The Lancet