Scientists reported that a U.K. patient suffering from a weak immune system was treated with COVID-19 and continued to receive it for nearly a year. This underscores the need to protect vulnerable individuals against the coronavirus.
There’s no way to know for sure whether it was the longest-lasting COVID-19 infection because not everyone gets tested, especially on a regular basis like this case.
But at 505 days, “it certainly seems to be the longest reported infection,” said Dr. Luke Blagdon Snell, an infectious disease expert at the Guy’s & St. Thomas’ NHS Foundation Trust.
Snell’s team plans to present several “persistent” COVID-19 cases at an infectious diseases meeting in Portugal this weekend.
Their study investigated which mutations arise—and whether variants evolve—in people with super long infections. The study involved nine people who were positive for HIV for at most eight weeks. They all had weak immune systems due to organ transplants or HIV/cancer treatment. For privacy reasons, none were named.
Multiple tests revealed that their illnesses lasted an average of 73 consecutive days. Two of them had the virus for longer than one year. Researchers previously said that 335 days was the longest time that a PCR test could confirm a case.
The persistence of COVID-19 can be rarer than the long COVID.
“In Long COVID, it’s generally assumed the virus has been cleared from your body but the symptoms persist,” Snell said. “With persistent infection, it represents ongoing, 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. Genetic sequencing revealed that the virus evolved over time and mutated as it changed.
Snell explained that these mutations are similar to ones later found in numerous variants. But, Snell did not say that any of the patients had spawned mutants that would be of concern. There’s also no evidence they spread the virus to others.
In early 2020, the person who had the longest-known infection was tested and confirmed positive. He received antiviral medication Remdesivir treatment, which was administered to him. The patient died in 2021. Researchers refused to identify the cause of death, but said that the victim had multiple other diseases.
Five patients survived. One patient survived the infected without any treatment while two others were cured with treatment. The third one was still suffering from COVID-19. At the last follow-up earlier this year, that patient’s infection had lasted 412 days.
Scientists hope that more treatment options will soon be available to people suffering from persistent infection.
“We do need to be mindful that there are some people who are more susceptible to these problems like persistent infection and severe disease,” Snell said.
Experts say persistent infections are very rare. However, there are still many patients with compromised immune systems at high risk for severe COVID-19. They are also trying to avoid the disease by staying safe once restrictions were lifted and masks began coming 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 research.
“Masking in crowds is a considerate thing to do and a way we can protect others,” he said.
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