The World Health Organization (WHO) on Wednesday, August 14, issued its highest level of international alert in the face of the resurgence of cases of mpox (or “monkey pox”) in Africa.
An epidemic that worries global health authorities. The circulation of mpox (formerly Monkeypox) in Africa prompted the World Health Organization (WHO) to trigger its highest global alert on Wednesday, August 14.
A total of 38,465 cases of the disease have been recorded in 16 African countries since January 2022, with 1,456 deaths, including a 160% increase in cases in 2024 compared to the previous year, according to the health agency Africa CDC.
Sometimes benign, sometimes fatal, this disease is rather easily identifiable because of the rash that follows the infection, this over a period of two to four weeks. Blisters or lesions can appear all over the body, which are generally accompanied by fever, headache, fatigue and muscle pain.
Monkeypox in DR Congo © AFP
• A worrying new strain
“We are facing multiple outbreaks with different strains in different countries, with different modes of transmission and different levels of risk,” said WHO Director-General Dr Tedros Adhanom Ghebreyesus.
This emergence of new strains, or “Clades”, is one of the drivers of concern about the resurgence of this disease. Clade 1 first circulated in the Congo and its basin, while clade 2 multiplied rather in West Africa.
Mpox: Why is “monkey pox” worrying health authorities again?
But it is the new clade 1b strain, derived from the first, that is focusing the fears of the scientific community. This version, identified since the end of 2023, first circulated in Congo before spreading to a series of African countries, including Egypt, Ivory Coast and Uganda. A circulation in territories that had been preserved until now.
In France, the Public Health France (SPF) agency is closely monitoring the situation but has not yet identified any patients carrying this new strain, although cases of Mpox have been occasionally observed in the country since the epidemic in summer 2022 according to information from the Parisian.
• What we know about the mode of transmission
At this stage, “it is not known whether strain 1b is more transmissible, but we do know that it is more efficiently transmitted,” said Dr Rosamund Lewis, WHO’s chief of monkeypox.
“It is probably more transmissible, and also more deadly than the variant that circulated in 2022,” said infectiologist Karine Lacombe, a guest on BFMTV on Wednesday evening.
As its name suggests, this virus is a zoonosis. Monkeypox initially emerged in an animal host. It probably crossed the species barrier during contact between humans and certain species of monkeys or terrestrial rodents, such as the tree squirrel.
“You can also contract the virus by eating undercooked infected animals,” he said. WHO in a dedicated page.
This is how strain I spread, while its descendant is transmitted more from person to person. Infections occur during “close” contact with the infected person, particularly during sexual (heterosexual and homosexual) or intimate exchanges. The disease can also be spread by the exchange of contaminated objects. A person with lesions on the skin, leaving virus on a surface.
“People with monkeypox are contagious until all of their lesions have crusted over, the scabs have fallen off and a new layer of skin has formed underneath, and all lesions on the eyes and body (mouth, throat, vagina and anus) have also healed, usually within two to four weeks,” says the WHO.
For his part, The Pasteur Institute emphasizes that “studies are underway to better understand the epidemiology, sources of infection and modes of transmission of this disease”, particularly due to the appearance of new strains.
• A disease that is “not limited to sexually active or gay people”
During the 2022 international outbreak, monkeypox was seen by the general public as primarily affecting men who have sex with men.
However, “the risk of contracting monkeypox is not limited to sexually active or gay people, or other men who have sex with men,” the WHO warns.
Those most at risk are those who have multiple risky sexual relationships with multiple partners, regardless of the partner’s gender, since both women and men are likely to contract the virus and subsequently spread it. Oral sex and sex with vaginal or anal penetration present risks.
• Transmission by blood or by asymptomatic people: unknowns remain
Scientists are playing cat and mouse with a virus that is constantly mutating. Several unknowns remain about how Mpox is transmitted, as noted by Center for diseases control (CDC).
Based on current scientific knowledge, there is no consensus on “how often a person with no symptoms” can transmit the disease. It is also unknown whether the virus can be “spread through respiratory secretions.”
But scientists are also looking at whether smallpox can be spread through bodily fluids: semen, vaginal secretions, urine, blood and feces.
• Three vaccines and exceptional treatments
While the move to maximum alert is a warning signal, there is no real cause for concern in France and Europe. The WHO is primarily seeking to protect the populations of African countries where health systems cannot absorb the wave.
The aim is also to facilitate access to vaccination, while three models have already been developed and have been approved by health authorities. Health authorities in Africa say they need 10 million doses, but only 200,000 are available at this stage. However, thanks to an emergency authorisation, organisations such as UNICEF will be able to obtain and distribute them.
Finally, treatments for smallpox have been developed, but their use remains limited due to a lack of data. “Their use is usually part of a clinical trial or expanded access protocol accompanied by data collection to improve our knowledge of how best to use them in the future,” explains the WHO.
