Monkeypox (“monkeypox” in English) has not caused any deaths in Europe, but the disease is progressing. With nearly 17,000 cases worldwide, World Health Organization (WHO) Director General Tedros Adhanom Ghebreyesus raised the highest level of monkeypox alert on July 23. Public Health France (SPF) has identified 1,567 patients in the country since May; 3% of them had to be hospitalized. This epidemic differs from the waves observed so far in a dozen African countries, in particular by the profile of the patients: the cases are almost exclusively men and most of them have had sexual relations with other men – “MSM”.
Why are MSM overrepresented among patients? First, keep in mind that SPF figures are necessarily incomplete. Screening is in its infancy and is made complex by the fact that the symptoms are non-specific. “This virus behaves like a great mimic of herpes or syphilis. It is therefore easy to miss the diagnosis., underlines Benjamin Davido, infectiologist at the Raymond-Poincaré hospital, in Garches (Hauts-de-Seine). In addition to the symptoms usually reported in endemic areas, some patients suffer from new conditions such as angina or proctitis (inflammation of the rectal mucosa).
“Anyone who has close physical contact with another person who has contracted monkeypox is at risk, regardless of their sexual orientation,” says Yannick Simonin.
Monkeypox is transmitted by direct contact, including through mucous membranes and skin lesions or by contact with contaminated surfaces or objects. It can also be transmitted by respiratory droplets, at short distance and during prolonged face-to-face exposure. “Anyone who has close physical contact with another person who has contracted monkeypox is at risk, regardless of sexual orientation,” emphasizes Yannick Simonin, lecturer specializing in emerging viruses at the University of Montpellier and calls for “be careful not to stigmatize the homosexual community” : “Monkey pox is not just about this community, even though cases are currently overrepresented there. »
Regardless of sexual orientation, the main factor of spread remains the multiplicity of sexual partners: 74% of the cases informed declared having had more than two sexual partners in the three weeks before the onset of symptoms. Of the cases investigated, 26% are HIV positive.
“We lack complete information, but the data rather confirms a single introductory event and then the spread, especially in the MSM community following super-spreading events”, says Mr. Simonin. The outbreaks that appeared in Spain and Belgium could thus be the cause of the very rapid spread of the virus within the gay community. A hundred positive cases were detected after Gay Pride at Yumbo in Maspalomas, Canary Islands, while another outbreak arose at the same time at the Darklands festival in Belgium in early May. However, monkeypox was already circulating before these festive events. While patient zero is unknown, Spanish health authorities have identified symptomatic cases of the disease in Madrid as early as April, reports El País.
Is monkeypox a sexually transmitted infection?
Beyond the high risk of contamination attributed to close contacts, the scientific community is closely monitoring the evolution of the virus into a sexually transmitted infection (STI). Studies conducted in Italy and Germany have shown the presence of the virus in the seminal fluid of some patients, although scientists have not established its infectious nature. The SPF data put forward another clue: 78% of patients present with a genito-anal rash. Virologist Yannick Simonin recalls that“an STI is a disease that is transmitted during sexual intercourse and which does not necessarily imply the presence of virus in sexual secretions”. As he explains, “The current hypothesis is that the transmission of this virus during sexual intercourse takes place largely at the level of lesions of the mucous membranes, in particular at the level of the anogenital region. »
The vaccine, which is 85% effective, is the only way to prevent monkeypox at the moment. Wearing a condom alone is not enough, which among other things distinguishes monkey pox from STIs
Benjamin Davido adds: “These lesions are contagious and infective. There were probably mutations in the virus that changed the chains of transmission. It is therefore not excluded that this virus becomes an STI. » Statements tinged with uncertainty for the moment. Sequencing the genome of the virus, six times longer than SARS-CoV-2, should make it possible to confirm an evolution of the modes of transmission, as indicated in this article published in the journal Nature. Yannick Simonin nevertheless weighs: “It is also very likely that this mode of transmission has been largely underestimated in areas where this virus is endemic, and relatively little studied. » Vaccination is the key to stopping the epidemic. According to Benjamin Davido, “The test-trace-isolate protocol is not suitable for this epidemic. We are in a fateful period. I call for the vaccination of people at risk to be completed by the start of the school year. » The vaccine, which is 85% effective, is the only way to prevent monkeypox at the moment. Wearing a condom alone is not enough, which among other things distinguishes monkeypox from STIs.
In addition to the identified contact cases, the High Authority for Health (HAS) extended preventive vaccination, on July 11, to MSM, multi-partner trans people, sex workers and professionals working in places of sexual consumption. With vaccination against smallpox stopped since 1984 following the eradication of the disease, the State has kept doses to guard against a bioterrorist attack. Although their number is classified secret-defense, the general direction of health (DGS) released 7,500 doses then 5,000 doses in mid-July. Asked by Franceinfo, the DGS announced that 30,000 doses have already been taken out of strategic stocks, of which 20,000 are already in the field.
“Expanding vaccination further at the moment does not seem necessary to me, especially since we do not know the number of doses available, so the priority is really to vaccinate people at risk”, says virologist Yannick Simonin. On social networks, testimonials are multiplying and associations for the fight against AIDS, Aides et Act Upcall for an acceleration of the vaccination campaign.
Eventually, the virus could be transmitted from humans to animals and evolve into a retro-zoonosis. “We could generate a kind of reservoir of this virus in Europe which would maintain it for much longer periods and make Europe an endemic zone”confirms Mr. Simonin, who recommends that people with the disease avoid contact with pets.