A patient who tested positive for COVID-19 remained so for 16 months until his death, the longest known case of infection, according to a study devoted to the evolution of the virus in immunocompromised patients.
The patient, whose identity has not been revealed, had first tested positive in mid-2020 and had breathing problems. He remained positive in all tests (about 45) until his death 505 days later, said Dr. Gaia Nebbia, co-author of the study.
This is the longest known case of COVID-19 infection, according to a press release from the European Congress of Microbiology and Infectious Diseases, which takes place in Lisbon from April 23 to 26 and where the study will be presented.
The study, conducted by researchers from King’s College London and Guy’s and St Thomas’ Hospital London, looked between March 2020 and December 2021 at nine immunocompromised patients with persistent infection with the virus.
All remained positive for at least eight weeks, two were positive for more than a year. Of the nine patients, four died and four eventually recovered. A last patient was still infected at the start of 2022, 412 days after his first positive test.
“Immunocompromised patients with persistent infection have little chance of survival, and new treatment strategies are urgently needed to end their infection,” said Nebbia.
The study aimed to study the mutations of the virus in infected patients for months. In one of the patients, the virus carried 10 mutations that appeared separately in several major variants, including Alpha, Gamma and Omicron.
“We wanted to characterize the viral evolution in these individuals who could accumulate mutations during their persistent infection. This is one of the hypotheses for the emergence of variants,” explains Ms. Nebbia. She points out that mutations of the virus were observed in five of the nine patients.
According to estimates from the Office for National Statistics published on Friday, 38.5 million people had COVID-19 in England between the end of April 2020 and mid-February 2022, or 70% of the population.