By Nancy Lapid
(Reuters) – The following is a summary of some of the latest scientific studies on the new coronavirus and efforts to find treatments and vaccines for COVID-19, the disease caused by the virus.
New York variant does not escape vaccines
The antibodies induced by the Pfizer / BioNTech and Moderna vaccines and antibody therapy by Regeneron Pharmaceuticals are able to neutralize a variant of the rising coronavirus in New York, show laboratory experiments. The New York variant contains mutations – E484K, S477N and D235G – that experts feared could reduce the antibody’s effectiveness. The new results “show that this potential problem will not be a problem,” said Nathaniel Landau of New York University, co-author of a report published on Wednesday in bioRxiv before the peer review. All mutations cause changes in the peak protein that the virus uses to infect cells and are located in the part of the peak protein where antibodies bind. The researchers exposed replicas of the New York variant to the blood of vaccine recipients or the combination of Regeneron antibodies used to treat infected patients. The vaccine-induced antibodies were “very effective in binding to the altered spike protein,” said Landau. Regeneron therapy was also “a potent blocker” of the virus. “Vaccines are very effective in stopping this highly contagious variant of SARS COV2, so it is more important than ever to be vaccinated,” said Landau. (https://bit.ly/3ssmR9u)
Over-spreading events bring virus variants to life
Over-propagation events, in which an infected person transmits the virus to many others, are essential for survival and the prevalence of new variants, the researchers found. If coronavirus transmission occurs in only one person at a time, a new variant is unlikely to gain a foothold and will usually die in the population by chance, said Daniel Reeves of the Fred Hutchinson Cancer Research Center in Seattle. “Even very strong variants can die if they are ‘unlucky’ and it is not by chance that they are transmitted in an overspread event,” he added. His team’s new mathematical models, posted on Wednesday at medRxiv before the peer review, show that the first over-spreading events that infect more than five people are essential for the survival of a variant, while the over-spreading events that infect more than 20 people are essential for its eventual predominance. Even a very infectious new variant usually needs an over-spreading event to help it overcome a current variant, explained Reeves. The findings provide one more reason to focus on preventing large over-spreading events, banning large indoor meetings, focusing on adequate ventilation in closed environments and requiring high-quality masks (K95 or N95) when group exposures are unavoidable, the researchers concluded . (https://bit.ly/39fZ4C7)
The coronavirus can infect the tissues of the mouth, spreading the infection
The new coronavirus can infect salivary glands, which can then play a role in transmitting the virus to the lungs or digestive tract via saliva, according to a report published Thursday in the journal Nature Medicine. The researchers first studied the cells in the mouth of healthy volunteers, looking for two proteins that the coronavirus uses as inputs. The cells of the salivary glands and gums express both proteins, making them vulnerable to infection. Next, the researchers found genetic material from the virus in the oral tissues of patients with COVID-19, indicating infection. They also found evidence that the virus was replicating in some of these cells. Among 27 volunteers with mild COVID-19, those with saliva viruses were more likely to report loss of taste and smell, suggesting that infected salivary glands may help explain some oral symptoms of COVID-19, the researchers said. “The study’s findings suggest that the mouth, through infected oral cells, plays a greater role in SARS-CoV-2 infection than previously thought,” said study co-author Kevin Byrd of the University of South Carolina. North on Chapel Hill in a statement. “When the infected saliva is swallowed or small particles of it are inhaled, we think it can transmit SARS-CoV-2” even more to the body. “(Http://go.nature.com/3spbFdQ)
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(Reporting by Nancy Lapid; Editing by Bill Berkrot)