Monkey pox: case in France, symptoms, transmission, should we be worried?

A first case “suspect” of monkey pox has been identified in France, announced the Directorate General of Health (DGS), Thursday, May 19. He is a 29-year-old man, residing in Île-de-France and with no history of travel to a country where the virus is circulating. “In the absence of seriousness, he is isolated at his home,” said the DGS in a press release published on Friday May 20 (source 1).

Since May 14, 2022, confirmed cases of Monkeypox virus infection not directly linked to travel to Central or West Africa have been reported in several European countries: in the United Kingdom, Portugal, Spain, Sweden, Italy, as well as in the United States and Canada. Suspected cases are being assessed in many countries and the situation is changing rapidly.

Monkey pox, also called « simian orthopox virus » is transmitted via a specific virus, « Monkeypox ». It is a rare viral zoonosis, which is mainly observed in isolated areas of central and western Africa. , near tropical rainforests, was discovered in the 1970s in the Democratic Republic of Congo, after human smallpox had been eradicated with the vaccine.

The World Health Organization states that: « The clinical presentation is similar to that observed in patients with formerly smallpox, but less severe » (source 2). The incubation of the disease can range from 5 to 21 days. Generally benign, it most often heals spontaneously, after 2 to 3 weeks.

In the first phase, called « invasive »we distinguish :

• fever (1 to 3 days),
• severe headaches,
• swollen glands,
• back and muscle pain,
• a lack of energy,
• etc

Then comes a second period, characterized by the appearance of a rash (on the face, first, then on the rest of the body). « It evolves in about ten days from maculo-papules (flattened base lesions) to vesicles (small liquid-filled blisters), then pustules and finally crusts », specifies the WHO.

Monkeypox is mainly transmitted to humans through contact with wild animals: « African rodents and non-human primates (such as monkeys) can harbor the virus and infect humans » says the US Agency for Disease Control and Prevention (source 4). But theSecondary transmission (from human to human) remains limited.

It is often the result of direct and close contactss with infected secretions from the respiratory tract (saliva, sneezes, sputters, etc.), skin lesions or mucous membranes of a sick person. You can also be contaminated in an « indirect » wayin contact with objects recently contaminated with biological fluids, or materials from a patient’s lesions (bedding, clothing, dishes, etc.).

« Typically, transmission occurs through the respiratory route, but suspected cases of infection suggest that transmission occurred through mucous membranes during sexual intercourse« , said the Spanish health authorities on discovering the first cases. Patients are experiencing « a positive development », they added.

According to Professor Jean-Daniel Lelièvre, head of infectious diseases at Henri-Mondor hospital, interviewed by our colleagues from Le Parisien (source 3), people in their fifties, vaccinated against smallpox before the 1970s, are able to very quickly produce antibodies against its cousin, monkeypox.

There is no specific treatment, or vaccine capable of preventing monkeypox. Patients usually recover spontaneously, in two to three weeks.

Nevertheless, vaccination against human smallpox is also effective against the form transmitted by monkeys: approximately 85% effective, according to the Institut Pasteur (source 5).

And Public Health France to add: « the disease is more serious in children and in immunocompromised people. It can be complicated by superinfection of skin lesions or respiratory, digestive, ophthalmological or neurological damage » (source 6). But at this stage, the cases reported in Europe are mostly mild.