(Reuters) – The following is an overview of some of the latest scientific studies of the new coronavirus and efforts to find treatments and vaccines against COVID-19, the disease caused by the virus.
Certain blood groups are less likely to get COVID-1
A large study adds evidence that people with type O or Rh-negative blood may have a slightly lower risk from the new coronavirus. Among 225,556 Canadians tested for the virus, the risk of a COVID-19 diagnosis was 12% lower, and the risk of severe COVID-19 or death was 13% lower in people with blood group O versus those with A, AB or B, reported researchers Tuesday in the Annals of Internal Medicine. People in any blood group that was Rh-negative were also somewhat protected, especially if they had O-negative blood. People in these blood type groups may have developed antibodies that can recognize some aspect of the new virus, said co-author Dr. Joel Ray from St. Michael’s Hospital in Toronto to Reuters. “Our next study will specifically look at such antibodies and whether they explain the protective effect,” Ray said. Whether or how this information may affect COVID-19 prevention or treatment remains unclear. (bit.ly/2JhQvws)
Vitamin D does not help in severe COVID-19 cases
Low levels of vitamin D have been associated with a higher risk of severe COVID-19, but high levels of vitamin D do not solve the problem. Increased vitamin D levels in critically ill patients did not shorten their hospital stays or lower their odds of being moved to intensive care, needing mechanical ventilation or dying, doctors in Brazil found. They randomly assigned 240 patients hospitalized with severe COVID-19 either a single high dose of vitamin D3 or placebo. Only 6.7% of patients in the vitamin D group had “deficient” levels of the nutrient compared to 51.5% of the patients in the placebo group, but there was no difference in the results according to a paper published on medRxiv prior to peer review. The same was the case when the researchers focused on the 116 patients with vitamin D deficiency before treatment. The authors say theirs is the first randomized trial of its kind to show that vitamin D supplementation “is ineffective in improving hospital stays or other clinical outcomes among inpatients with severe COVID-19.” (bit.ly/3mfqOeH)
Triggers of COVID-19 “cytokine storm” identified
A form of inflammatory cell death called panoptosis triggers the storm of cytokines or inflammatory proteins that cause critical illness in COVID-19, researchers say. During panoptosis, “the cells spit out their contents instead of neatly unpacking them,” as happens during routine cell death, said Thirumala-Devi Kanneganti of St. Petersburg. Jude Children’s Research Hospital to Reuters. Neighboring cells see the waste, including cytokines, as a sign of danger and respond by secreting more cytokines so that the cytokine storm can build up, Kanneganti said. Her team identified a synergy between two cytokines, TNF-alpha and IFN-gamma, as the cause of panoptosis in COVID-19. Mice given TNF-alpha and IFN-gamma developed symptoms and organ damage at COVID-19 and died quickly, Kanneganti said. Treatment with antibodies that neutralize these two cytokines protected the mice from death, not only from COVID-19, but also from other life-threatening diseases involving cytokine storms, such as sepsis, her team at Cell reported. Trials are needed to test these treatments in humans, Kanneganti said. (bit.ly/375VBEa)
COVID-19 survivors benefit from home treatment
COVID-19 survivors benefit from home treatment after being discharged from hospital, new data shows. Researchers from the visiting nursing service in New York, the University of Pennsylvania, and Villanova University studied 1,409 patients receiving home care, nearly half of whom were under 65 years of age. When they were discharged, 80% were still short of breath, most reported anxiety or confusion, and more than 80% needed help to walk, dress, and bathe. After an average of 32 days of home health care, 94% no longer needed the service. The vast majority were not fully recovered, but most symptoms were significantly improved, as was the patients’ ability to perform daily activities. Only 10% needed to be resumed, researchers reported Tuesday in the Annals of Internal Medicine. “Only 11% of COVID-19 survivors nationwide were discharged from hospital settings with qualified home health care,” said co-author Margaret McDonald of the visiting nurse in New York. This study “suggests that HHC is significantly underused for the recovery of hospitalized COVID-19 patients.” (bit.ly/39kY7Jz)
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Reporting by Nancy Lapid; Editing by Tiffany Wu