Staff writers
Dutch medical scientists are warning about the risk of viruses mutating over long periods in infected immunocompromised people.
Forthcoming research from the group relates to a previously reported case of a 72-year-old Dutch man who was infected with the SARS-CoV-2 virus for a record 613 days before dieing from a blood disorder.
The research, which is not yet published or peer-reviewed, will this week be presented at a global congress of the European Society of Clinical Microbiology and Infectious Diseases.
They tracked the evolution of the virus within the man’s system, while he was administered the antivirals sotrovimab, sarilumab and dexamethasone.
Samples taken between February 2022 and September 2023 noted more than 50 mutations in the virus’s genetic sequence. Evidence of immune escape was also observed in the form of changes multiple changes to the virus spike protein.
During the period of infection, the virus evolved resistance to sotrovimab.
In their presentation, the 6 researchers will argue that immunocompromised patients need close monitoring, not only for their own health outcomes but also for signs of viral change that could spread beyond the patient.
They report that in this case the highly mutated, drug-resistant variant was not passed to anyone else.
“This case underscores the risk of persistent SARS-CoV-2 infection in immunocompromised individuals as unique SARS-CoV-2 viral variants may emerge due to extensive intra-host evolution,” the researchers write.
Though they note this is an “extreme” case, they report also monitoring other prolonged infections ranging from a month to 2 years in length.
“Prolonged infections in immunocompromised patients are much more common compared to the general community,” they say “ However, from the viewpoint of the general public, prolonged infections remain rare as the immunocompromised population is only a very small percentage of the total population.”