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A Connecticut cancer patient had COVID-19 for at least 471 days, and the virus appeared to evolve into several new lineages, researchers at Yale University say in a new study.
The findings show that "untreated chronic infections accelerate SARS-CoV-2 evolution, ultimately providing opportunity for the emergence of genetically divergent and potentially highly transmissible variants as seen with Delta and Omicron," the study says.
Scientists following COVID-19 variants found a lineage called B.1.517 in Connecticut after it stopped appearing much elsewhere. They traced it back to the cancer patient, in his or her 60s, who has lymphoma.
That person tested positive for COVID-19 from November 2020 through at least March of this year, the study says.
The patient had only a few mild symptoms at the beginning and was almost entirely free of Covid-19 symptoms during the period. The patient was infectious with high viral loads throughout most of the period, according to NBC News.
"The patient continues to test positive for SARS-CoV-2 471 days and counting after the initial diagnosis," the study says.
During the observed time, the virus evolved in the patient, presenting three distinct lineages.
Researchers found the virus evolving at two times the speed inside this patient as it does generally.
The study has not been peer reviewed.
MedRxiv: "Accelerated SARS-CoV-2 intrahost evolution leading to distinct genotypes during chronic infection"
NBC: "Connecticut Patient Had COVID for 471 Days, Evolved 3 New Lineages: Study"
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Cite this: Virus Evolved in Patient Who HadCOVID for 471 Days - Medscape - Jul 06, 2022.