Will anyone be surprised if one hears that a patient tested positive for COVID-19 for 505 days? No need to be surprised as a patient in UK tested positive for COVID-19 for 505. The previous longest known PCR confirmed case is thought to be 335 days. The UK researchers mentioned this at this year’s European Congress of Clinical Microbiology & Infectious Diseases (ECCMID) in Lisbon, Portugal. The researchers, who studied the virus in nine Covid patients, also provide evidence that new Covid variants may arise in immunocompromised individuals.
First author, Dr Luke Blagdon Snell, of Guy’s and St Thomas NHS Foundation Trustsaid that new variants of SARS-CoV-2 emerged throughout the pandemic. “Some of these variants transmit more easily between people, cause more severe disease, or make the vaccines less effective. One theory is that these viral variants evolve in individuals whose immune systems are weakened from illness or medical treatments like chemotherapy, who can have persistent infection with SARS-CoV-2, the researcher said.
The study involved nine immunocompromised patients who tested positive for the virus for at least eight weeks. Infections persisted for 73 days, on average, but two patients had persistent infections for more than a year.
Regular sampling and genetic analysis of the virus showed that five of the nine patients developed at least one mutation. Some individuals developed multiple mutations associated with variants of concern, such as the Alpha, Delta and Omicron variants. The virus from one individual contained 10 mutations that would arise separately in’ variants of concern, such as the Alpha, Gamma and Omicron variants.
Dr Snell noted that this was evidence to show that mutations found in variants of concern do arise in immunocompromised patients. This supported the idea that new variants of the viruses may develop in immunocompromised individuals, the author said.
Five of the nine patients survived. Two of those five cleared SARS-CoV-2 in section without treatment, two cleared the infection after treatment with antibody therapies and antivirals, and one individual has ongoing infection. As their last follow-up in early 2022, the patient with ongoing infection had been infected for more than one year (412 days). At their last follow-up in early 2022, the patient with ongoing infection had been infected for more than one year (412 days). The person has been treated with mdnoclonal antibodies to try to clear their infection. If this person remains positive at their next follow-up appointment, they will likely pass the previous longest known infection of 505 days described in this report.
