The Brazilian variant can re-infect survivors of the virus; COVID-19 vaccine antibodies pass into breast milk

(Reuters) – 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.

Variant in Brazil more likely to re-infect survivors

A variant of the coronavirus circulating in Brazil is likely able to re-infect people who have survived infections with previous versions of the coronavirus, new data suggests. The variant that emerged in Brazil, called P.1, carries a mutation that is already known to make a variant prevalent in South Africa more difficult to treat with antibodies and more difficult to prevent with available vaccines. New data suggests that in many recovered patients, immunity to previous versions of the virus does not confer immunity to P.1. Researchers tested the ability to neutralize antibodies in plasma samples taken from survivors of COVID-19 caused by earlier versions of the virus. Plasma “had a 6-fold less neutralizing capacity” against the P.1 variant than against earlier versions of the virus, researchers reported Monday ahead of peer review on a pre-print server owned by The Lancet journal . “A weaker neutralizing capacity of anti-SARS-CoV-2 antibodies and partial immunity against new variants suggest that reinfection could occur in recovering or even vaccinated individuals,” said the authors. In another article published Wednesday on medRxiv ahead of the peer review, some of the same researchers estimated that out of 100 COVID-19 survivors due to previous versions of the virus, 25 to 60 could be re-infected if exposed to the virus. P.1 variant because their antibodies could not protect them. As of Thursday, according to the United States Centers for Disease Control of Prevention, there have been 13 cases of COVID-19 due to P.1 in the United States. (bit.ly/2PyNFGt; bit.ly/3qeqq1a)

COVID-19 vaccine antibodies pass into breast milk

COVID-19 antibodies induced by Pfizer Inc / BioNTech and Moderna Inc vaccines can pass into breast milk, a small study suggests, although it is not yet known how long the antibodies will be present. Six nursing mothers who planned to receive both doses of the Pfizer / BioNTech or Moderna vaccines provided researchers with pre- and post-vaccination milk samples, with the last sample taken two weeks after the second vaccine. None of the women had been infected with the coronavirus. A week after the first injection, all of the women had COVID-19 antibodies in their breast milk. Antibody levels dropped slightly afterwards and then rose sharply after the second stroke. Both vaccines were equally effective at inducing antibodies, although antibody levels vary from woman to woman, the medRxiv research team reported on Tuesday before the peer review. “More research is needed on the longevity of the antibody response in breast milk, as well as the magnitude and duration of the effect on infant immunity to the virus,” the researchers said. (bit.ly/3kNOPJP)

Common neurological problems in hospitalized children with COVID-19

Most children and adolescents are spared from severe COVID-19, but among those who require hospitalization, temporary neurological effects are common, researchers say. In their study of 1,695 patients aged 21 or younger hospitalized with COVID-19 or a COVID-19-related illness known as multisystem inflammatory syndrome, 365 – or 22% – had neurological complications, including 43 ( 12%) with life-threatening neurological disorders. disorders such as stroke and central nervous system infections. Other neurological effects included seizures, headaches, weakness, loss of smell and taste, and altered consciousness or confusion. Neurological involvement in most patients was transient and resolved by the time they left the hospital, according to a report published Friday in JAMA Neurology. Because they only studied hospitalized children, the range and rate of neurological complications may be an underestimate of the actual problem, the authors said. They said more research is needed both to determine the true incidence and to follow these children over the long term. (bit.ly/2PCxXKC)

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