Leukemia patients get rid of the new coronavirus infection for at least 70 days

most people infected with SARS-CoV-2 show active transmission of the virus within about 8 days, but there are significant differences between people. It is important to know how long people can remain active in infection because it provides new details about a disease and virus that are still not fully understood and can provide information for public health decision-making. Researchers reported a rare case in Cell recently in which a woman with leukemia and a low antibody count was infected with the new coronavirus for at least 105 days, was infectious for at least 70 days, and remained asymptomatic.
study, we really didn't know the duration of detox. "As the virus continues to spread, more people with immunosuppressive disorders will be infected, and it is important to understand how SARS-CoV-2 behaves in these populations," said Vincent Munster, senior author of the paper and a virologist at the National Institute of Allergy and Infectious Diseases (NIAID). Munster
an expert on new infectious diseases, began publishing his study on SARS-CoV-2 in January. In April, infectious disease expert and co-author Francis Riedo contacted him about a patient in Kirkland, Washington, who was infected early in the COVID-19 pandemic. Riedo's patient tested positive for PCR several times in a few weeks, and he wondered if the patient was still spreading the virus.
patient was a 71-year-old woman with low immune function due to chronic lymphocytic leukemia and access to hypoproproteinemia. She has never had any COVID-19 symptoms. She was admitted to hospital with severe anemia and was screened for the new coronavirus, and doctors noted that she had been a regular visitor to a rehabilitation facility that had experienced a major outbreak.
Munster Laboratory, based at the NIAID Rocky Mountain Laboratory in Hamilton, Montana, began studying samples regularly taken from the patient's upper respiratory tract. They found that the infectious virus persisted for at least 70 days after the first test positive, and that the woman did not completely remove the virus until the 105th day. "It's something we expected, but it's never been reported before." Munster said.
believe the patient's virus has been contagious for so long because her damaged immune system does not allow her to react. Blood tests showed that her body could never produce antibodies. At one point, she received a recovery plasma treatment, but Munster said it was ineffective because of its low antibody concentration. Although she was unable to produce an antibody response, she never developed symptoms.
team sequenced all virus samples taken from patients to see how the virus might change during infection. Samples taken at different times showed different explicit gene variants. However, the researchers don't think these mutations have an effect on the survival of the virus because they don't see evidence of natural selection. If a mutation seems to give the virus a survival advantage and becomes a dominant variant, then natural selection is involved, but none of the mutations are dominant. They also tested whether the mutations affected the virus's ability or speed to replicate, but found no difference.
Munster said he knew it was the longest asymptomatic case of SARS-CoV-2 infection. "We've seen similar cases of influenza and MIDDLES, which are also caused by coronavirus," he said. We hope to see more such reports in the future. (Source: Tang Erdu, China Science Daily)
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