the virus is often transmitted before the first symptoms, according to a study published by the “British Medical Journal”

The monkeypox virus is often transmitted before the first symptoms appear, suggests a study published Wednesday, November 2 in the British Medical Journal (BMJ). These results still need to be refined, but they could play a decisive role in the future management of the epidemic.

This work was carried out in the United Kingdom, one of the first countries where the current epidemic spread. If this one, which struck nearly 80,000 patients and caused around thirty deaths in the world, seems today to be reduced, the health authorities remain vigilant. The WHO has thus decided to maintain the maximum health alert on Tuesday, in particular because of new infections in certain countries.

The authors of the study, led by epidemiologist Thomas Ward, attempted to analyze the risk of transmission “silent”, that is, during the incubation period, before the patient is struck by the first symptoms. They therefore examined data from almost 3,000 UK patients, mostly men who have had same-sex relationships.

This review allowed to get an idea of ​​two types of delays and to compare them. The first is the incubation time, during which the patient carries the virus without knowing it. The second is the time that elapses from the onset of symptoms in a given patient, until their appearance in the one to whom he transmitted the disease. The researchers concluded that this second delay tends to be shorter than the first, which suggests transmission before the first symptoms.

British researchers estimate that this pre-symptomatic transmission represents more than half of cases, and can occur up to four days before symptoms.

However, these results still need to be confirmed by other studies, say other researchers in a commentary also published by the BMJ. At present, and even with this work, the pre-symptomatic transmission “is not irrefutable”they warn.