The virus does not threaten the United States blood supply; high levels of vitamin D do not protect against COVID-19

The following is a summary of some of the latest scientific studies on the novel coronavirus and efforts to find treatments and vaccines for COVID-19, the disease caused by the virus.

Coronavirus does not threaten United States blood supply

Current guidelines for screening U.S. blood donors for symptoms of COVID-19 and for a history of recent infections effectively protect the blood supply from contamination with the novel coronavirus, the researchers say. In a study conducted for the National Institutes of Health, researchers tested nearly 18,000 “minipools” of blood samples, that is, blood samples collected from a total of about 258 000 donors from all over the country. Only three minipools contained genetic material from the virus, according to a report published in the journal Transfusion. In all three cases, viral levels were low. In the only minipool that could be tested for infectivity, the viral material was non-infectious, the researchers said. “Other studies have shown that in rare cases where a blood sample is positive, transmission by blood transfusion has not occurred,” said co-author Sonia Bakkour of the University of California at San Francisco. in a press release. “Therefore, it appears safe to receive blood as a transfusion recipient and continue to donate, without fear of transmitting COVID-19 as long as current screenings are used. “(https://bit.ly/3iblpG9)

High Vitamin D Levels Do Not Protect Against COVID-19

Low levels of vitamin D have been linked to higher risks of COVID-19 and more serious illness, although no studies have proven that vitamin D deficiency is in fact to blame. A study published Tuesday in PLoS Medicine suggests that increasing vitamin D levels with supplements wouldn’t help. Researchers studied more than 1.2 million people of European descent from 11 countries, some of whom had genetic variants that result in naturally higher levels of vitamin D. People with these variants did not have a lower risk of coronavirus infection, hospitalization or severe COVID-. 19, the researchers reported. Their results suggest that increasing vitamin D levels in people with deficiency likely wouldn’t help fight the coronavirus, and they don’t think randomized trials testing vitamin D supplementation would be worth it. Other experts, however, would still like to see such trials, especially in people of African and non-European descent. (https://bit.ly/3g62hqA)

Immune system workaround helps blood cancer patients with COVID-19

In blood cancer patients who lack antibody-producing cells, other immune cells may compensate to help fight the coronavirus, new research shows. People with blood cancers – like leukemia, lymphoma, and myeloma – often lack antibody-producing immune cells called B cells, especially after treatment with certain medications. Without enough B cells and antibodies, they are at risk for severe COVID-19. But other immune cells, called T cells, learn to recognize and attack the virus, according to a report in Nature Medicine. Blood cancer patients in the study were more likely to die from COVID-19 than patients with solid tumors or without cancer. But among blood cancer patients, those with higher levels of CD8 T cells were more than three times more likely to survive than those with lower levels of CD8 T cells. The authors speculate that CD8 T cell responses to COVID-19 vaccines could protect blood cancer patients even if they do not have typical antibody responses. “This work may help us counsel patients while we wait for more specific vaccine studies,” co-author Dr. Erin Bange of the University of Pennsylvania said in a statement. While patients’ vaccine response “is probably not as robust as that of their friends / family who do not have blood cancer, it is still … potentially life-saving,” Bange added. (https://go.nature.com/2STOVWf)

In some long cases of COVID, air is trapped in the lungs

Some COVID-19 survivors with persistent respiratory symptoms suffer from a condition called “air entrapment,” in which inhaled air gets stuck in the small airways of the lungs and cannot be exhaled. Researchers studied 100 COVID-19 survivors who still had breathing problems, such as cough and shortness of breath, on average more than two months after their diagnosis. A total of 33 had been hospitalized, including 16 who needed intensive care. The amount of lung area with so-called ground glass opacities on imaging studies – a typical sign of lung damage from COVID-19 – was higher in the hospitalized group than in people with milder disease, and it was even higher in patients who required intensive care. However, the severity of COVID-19 made little difference in the average percentage of lungs affected by air entrapment. It was 25.4% in outpatients, 34.5% in those hospitalized without intensive care, and 27.2% in critically ill patients. By comparison, this proportion was 7.3% in a group of healthy volunteers. Air entrapment was largely limited to the patients’ narrowest airways, according to a report released on medRxiv on Saturday ahead of the peer review. “The long-term consequences” of small airway disease in these patients “are not known,” the authors said. (https://bit.ly/3pcekXo)

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