Cell study: Asymptomatic new crown patients positive for 105 days

previous studies have shown that most SARS-CoV-2 infection patients show strong infectiousness within about 8 days, but there are significant differences between people, especially in people with low immunity or different manifestations. On November 4th Cell, a leading academic journal, published a study online by researchers from the National Institutes of Health's Institute of Allergy and Infectious Diseases (NIAID) and others, providing new details on the issue or advice on public health decisions.
team reported a particular case of a new corona: a woman with low immune function with leukemia was infected with the new coronavirus for at least 105 days, and detox for at least 70 days was potentially contagious and remained asymptomatic. The study, entitled "Case Study: Prolonged Infectious SARS-CoV-2 Shedding from an asymptomatic immunocomprom cancerized patient." Wassed by NIAID virologist Dr. Vincent J. Munster and infectious disease specialist Francis X. Riedo of Evergreen Health Medical Center in Kirkland, Washington. The study team reported a 71-year-old woman. The patient has a 10-year history of chronic lymphocytic leukemia (CLL), access to hypopropanosis
emia, anemia, chronic white blood cell growth, february 12, 2020, she was called to the emergency department with low back pain, lower limb pain. On 14 February, the patient underwent the operation and was transferred to a rehabilitation centre on 19 February. On 25 February, she was admitted to hospital again with anemia, and the next day she had a chest X-ray, which showed normality.
the patient was unable to return due to an outbreak of COVID-19 confirmed by a previous rehabilitation centre, and the results of a chest CT examination conducted on 28 February were not abnormal. During this time, the patient does not have any respiratory or other systemic symptoms.
, however, tested positive on March 2 for SARS-CoV-2 in light of an outbreak at her previous rehabilitation center. After being diagnosed with a positive SARS-CoV-2, the patient was isolated in a negative pressure ward. Over the next 15 weeks, she underwent 14 more SARS-CoV-2 tests. Until June 15, 105 days after the initial positive test, the test results remained positive.
, the patient tested negative for four consecutive swabs from June 16 to July 16, suggesting that the new coronavirus had been removed from the patient's body.
s what we expected, but it's never been reported before," Munster said. Munster, an expert on inged infectious diseases, began publishing research on SARS-CoV-2 in January. In April, Riedo contacted him to discuss the patient in the paper.
we started this study, we really didn't know much about the duration of the virus's discharge, " he said. As the virus continues to spread, more people with a range of immunosuppressive disorders will be infected, and it is important to understand how SARS-CoV-2 behaves in these populations. "It is worth noting that the patient received some treatment during the infection. Serum antibody testing showed that the patient's new coronavirus S protein and subject binding domain (RBD) specific IgG antibody titration was very low, and no SARS-CoV-2 specific neutral antibody was detected. However, although she was unable to produce an antibody response, she never showed symptoms.
patients also received recovery plasma treatment at one point. On 12 May (71st day after positive test) and 23rd May (82nd day after positive test), patients received recovery plasma therapy, respectively. After the first infusion, the IgG antibody titration increased, the body has not yet detected the melioth antibody;
, after two plasma infusions, the patient tested positive. This indicates that plasma therapy during recovery has not succeeded in removing viral infections from the patient's upper respiratory tract.
team also sequenced all virus samples taken from patients to see how the virus might change during infection. The results showed that samples taken at different times showed different advantageous gene variants. However, the team believes that these mutations have no effect on the virus's survival time because they do not see evidence of natural selection, and if one of the mutations provides the virus with a survival advantage, there will be selective advantage variation. They also tested whether the mutations affected the virus's ability or speed of replication through cellular experiments, and found no difference.
Munster said it was the longest known case of SARS-CoV-2 infection but still asymptomatic. "We have seen similar cases of long-term infections in influenza and Middle East Respiratory Syndrome (MERS), both of which are also caused by coronavirus," he said. We hope to see more cases like ours in the future to provide information for outbreak prevention and control. "