A normal person clears up the coronavirus in a few weeks after infection. But some people with a faltering immune system take much longer, or never succeed.
That was the case with a man who was cared for at Amsterdam UMC. He was infected with the coronavirus for no less than 613 days. A record, say the Dutch researchers who will explain the case at a conference on infectious diseases (ESCMID) in Barcelona.
Faltering immunity
The 72-year-old man was admitted to the Amsterdam hospital in February 2022 with a corona infection. Although he had been vaccinated several times, he had not built up immunity against the coronavirus, a test showed. That was not surprising, because the man’s immune system was severely suppressed.
The man suffered from a blood disease and had received a stem cell transplant for it. Because complications occurred afterwards, he was given a medicine that destroys all B cells. These white blood cells help to produce antibodies, also against the coronavirus.
That is why the man was given so-called monoclonal antibodies through an IV, which should help clear up the virus. But that didn’t work, the doctors say. After just three weeks, the virus in his body had mutated into a variant that could bypass one of the antibodies administered.
More than 50 mutations
And so it would continue for 613 days, until the man finally died from the effects of his blood disease. During that period, the doctors took 27 samples with a nose or throat swab. He had to be admitted to hospital repeatedly because his chronic corona infection regularly flared up.
The genetic material that the researchers collected from the virus shows that the virus mutated more than 50 times in the patient’s body between February 2022 and September 2023. “The long-term infection led to the emergence of a new variant that evades the immune system,” the researchers write. “Fortunately, no further infections with this highly mutated variant have been identified.” Analysis of all samples from the Amsterdam region shows that his variant (or a variant thereof) does not occur.
It is not the first time that it has been established that patients with a weakened immune system fail to clear the virus and therefore remain infected for a long time. A review study in 2022 showed that this occurs frequently in patients without B cells. Even when new variants emerged with an inexplicably large number of mutations, such as the British variant and omikron, it was suggested that the variant originated in one patient in which the virus learned to evade administered antibodies.
Seek balance
“This underlines the risk of new variants in immunocompromised patients,” the researchers say. “Given the potential danger to public health, it is very important to monitor this closely with genome analyses.”
But they also point out that a balance must be found between public health and humane care for a very sick patient at the end of his life. “This can be done, for example, by making tests quickly available to close contacts as soon as they develop symptoms.” They also note that not every new variant in an immunocompromised patient can break through into the broader population, which has built up immunity.
