The person in question suffered from an immune deficiency and took part in a study intended to provide information on how the virus changes in long-term patients. As the release shows, the scientists found indications that new virus variants can develop in immunocompromised patients. This weekend, the results will be presented at an international congress in Lisbon.
The typical infection lasts two weeks.
According to the researchers, a coronavirus infection usually lasts one to two weeks in people with a functioning immune system. Even if the virus can still be detected by a PCR test for up to 90 days, it can no longer replicate. This is different for people with a severely weakened immune system, where active infections can last long.
As part of the study, nine Covid-19 patients were observed who had a weakened immune system due to other diseases or therapies. On average, they were infected for 73 days. In two patients, the infection lasted longer than a year.
New variants arise in immunocompromised patients.
“Regular sampling and genetic analysis of the virus showed that five of the nine patients developed at least one mutation present in variants classified as worrying,” the statement said. Ten mutations were found in one patient, which individually occur in worrying variants such as alpha, gamma, or omicron.
“This provides evidence that mutations present in variants of concern are present in immunocompromised patients and supports the idea that new variants of the virus may arise in immunocompromised individuals,” said Luke Blagdon Snell of Guy’s and St Thomas’ NHS Foundation Trust.
However, it is essential to emphasize that none of the patients observed in the study developed a virus variant that has become one of the widespread variants of concern, Snell said. It is also unclear whether the Alpha, Delta, and Omikron variants were created in this way.