By CBSBoston.com Staff

BOSTON (CBS) – For 154 days last year, a man was in and out of Boston hospitals fighting a losing battle with COVID-19. He did not survive, but researchers say his rare case could help them better understand how the virus mutates.

The man, whose identity was not released, was first diagnosed in the spring of 2020. Dr. Jonathan Li, an infectious disease specialist at Harvard Medical School, has been studying the case since then.

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The 45-year-old man lived with the virus for 154 days which they believe is due in part to an autoimmune disease he had. Because he was immunocompromised, his body may not have been strong enough to fully eradicate the virus. As a result, that could force the virus to adapt. In a healthy person the virus is usually gone in about two weeks.

Doctors saw the man every few weeks at Brigham and Women’s Hospital and each time, they were able to get a sample of the virus. Every sample was different, showing the virus was mutating.

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Overall, it mutated more than 20 times over five months.

“It was challenging at times to try to tease out which part of his symptoms that he was being re-admitted for was because of his underlying autoimmune disorder, and what was due to COVID,” Dr. Li said. “And I have to say that I think that it’s still not fully clear which hospitalization was due to COVID, and which one was due to his autoimmune disorder.”

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Dr. Li and his colleagues first published their findings in November, but they are getting new attention now because of the mutant strains of coronavirus. Dr. Li said he and his colleagues have spoken with other medical teams that say they have seen similar cases of the virus mutating while living inside a person with an autoimmune disease.

CBSBoston.com Staff