the maximum contagiousness lasts 5 days

Studies follow one another and confirm that people infected with Covid-19 are particularly contagious in the first few days following the onset of symptoms. A British meta-analysis, published November 19 in the scientific journal The Lancet, confirms that no live virus was detected beyond 9^th day. He adds that the peak of contagiousness extends to 5^th day after the onset of symptoms.

Inactive fragments of the virus present up to 17 days later

The results of this study confirm the importance of isolation from the appearance of the first symptoms. To reach these conclusions, the researchers have 79 global studies aimed at determining the period of maximum contagiousness for patients with Covid-19. The active virus is present in nasal swabs for up to nine days after symptoms appear. Inactive fragments of the virus were found for up to 17 days after the onset of symptoms. In 97.5% of cases, people who develop the disease do so within 11.5 days of exposure to the virus.

“Other studies have shown that infected people are also contagious 48 hours before they exhibit symptoms, adds Professor Bruno Hoen, specialist in infectious diseases, medical director of the Institut Pasteur, a Parisian, which reminds us that even asymptomatic people can transmit the virus. Probably shorter than those with symptoms. Their contagiousness is lower than that of symptomatic people, perhaps because they do not cough. “

A woman who has been contagious for 70 days

However, there are special cases of people whose duration of contagion seems infinite. A 71-year-old woman recently piqued scientists’ curiosity by remaining contagious for 70 days despite showing no symptoms. In total, more than a dozen positive diagnostic tests have been reported, meaning the woman has retained SARS-CoV-2 particles in her body for several months. This woman’s case could be linked to her cancer and immunosuppressive treatments, which weaken the immune system.