A UK patient had COVID-19 for 505 days in a row

A British patient with a severely weakened immune system had had COVID-19 for nearly a year and a half, scientists reported, underscoring the importance of protecting vulnerable people from the coronavirus.

There is no way to know for sure if it was the longest lasting COVID-19 infection because not everyone gets tested, especially not on a regular basis like this case.

But after 505 days, “it certainly appears to be the longest-reported infection,” said Dr. Luke Blagdon Snell, an infectious disease expert at Guy’s & St. Thomas’ NHS Foundation Trust.

Snell’s team plans to present several “ongoing” COVID-19 cases this weekend at an infectious disease meeting in Portugal.

Their research examined what mutations arise — and whether variants arise — in people with super-long infections. It concerned nine patients who tested positive for the virus for at least eight weeks. They all had weakened immune systems from organ transplants, HIV, cancer or treatment for other diseases. None were identified for privacy reasons.

Repeated tests showed that their infections lasted an average of 73 days. Two had the virus for more than a year. Earlier, researchers said the longest known case to be confirmed with a PCR test lasted 335 days.

Persistent COVID-19 is rare and different from Lung COVID-19.

“In Lung COVID, it is commonly believed that the virus has been cleared from your body, but the symptoms remain,” Snell said. “With ongoing infection, it represents continued, active replication of the virus.”

Each time researchers tested patients, they analyzed the genetic code of the virus to make sure it was the same strain and that people didn’t get COVID-19 more than once. Still, genetic sequencing showed that the virus changed over time and mutated as it adapted.

The mutations were similar to the mutations that later showed up in widespread variants, Snell said, although none of the patients spawned new mutants that became variants of concern. There is also no evidence that they have spread the virus to others.

The person with the longest-known infection tested positive in early 2020, was treated with the antiviral drug remdesivir, and died sometime in 2021. Researchers declined to name the cause of death, saying the person had several other illnesses.

Five patients survived. Two cleared the infection without treatment, two cleared it after treatment, and one still has COVID-19. At last follow-up earlier this year, that patient’s infection had lasted 412 days.

Researchers hope more treatments will be developed to help people with persistent infections beat the virus.

“We have to keep in mind that there are people who are more susceptible to these problems, such as persistent infections and serious illnesses,” Snell said.

While persistent infections are rare, experts said there are many people with compromised immune systems at risk for severe COVID-19 who are trying to stay safe after governments lift restrictions and masks began to go off. And it’s not always easy to know who they are, said Dr. Wesley Long, a pathologist at Houston Methodist in Texas, who was not part of the study.

“Making in crowds is a thoughtful thing and a way to protect others,” he said.

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This post A UK patient had COVID-19 for 505 days in a row

was original published at “https://time.com/6169717/persistent-covid-19-infection/”