Home Business amount Most unvaccinated children lack antibodies after COVID; GSK vaccine shows promise against Omicron

Most unvaccinated children lack antibodies after COVID; GSK vaccine shows promise against Omicron


March 21 (Reuters) – The following is a summary of some recent studies on COVID-19. They include research that deserves further study to corroborate the findings and that has not yet been certified by peer review.

Most unvaccinated children lack antibodies after COVID-19

Most children and adolescents do not have COVID-19 antibodies in their blood after recovering from SARS-CoV-2 infection, new data has confirmed.

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Beginning in October 2020, researchers in Texas recruited 218 subjects ages 5 to 19 who had recovered from COVID infections at some point in the past. Each provided three blood samples, three months apart. More than 90% were unvaccinated when they enrolled in the study. The first blood test showed antibodies linked to the infection in only a third of the children, the researchers reported online Friday in Pediatrics. Six months later, only half of those who had the antibodies still had them. The study was designed to detect the presence of antibodies, which are only one part of the immune system’s defences, not the amount of antibodies. The level of protection, even in those with antibodies, is unclear. Researchers found no difference depending on whether a child was asymptomatic, the severity of symptoms, when they had the virus, or due to weight or gender.

“It was the same for everyone,” Sarah Messiah of UTHealth School of Public Health Dallas said in a statement. “Some parents…think that just because their child has had COVID-19, they are now protected and don’t need to be vaccinated,” Messiah said. “We have a great tool available to give children extra protection by getting vaccinated.”

GSK’s experimental vaccine shows promise against Omicron

A booster shot of an experimental vaccine developed by GSK (GSK.L) showed “durable protection” against the Omicron variant in rhesus macaques, according to new data.

The monkeys had received two initial doses of the vaccine plus a booster 6 or 12 months later. Blood samples from the boosted primates showed “remarkably high” levels of antibodies that could neutralize both the original strain of the virus and the Omicron variant that skyrocketed infections, the researchers reported. Sunday on bioRxiv before peer review. The animals’ second-line immune defenses were also “substantial and persistent”, they said. The vaccine, called GBP510 and developed in partnership with SK Bioscience (302440.KS), triggers immune system responses by delivering copies of a key part of the coronavirus’ surface spike protein. The protein “subunits” are studded on nanoparticles to resemble the virus itself. These components are supplemented with an adjuvant that boosts immune system responses, explained Bali Pulendran of Stanford University in California.

“Vaccination with two doses … followed a year later by a booster shot … plus an adjuvant, led to very durable antibody responses and protection against Omicron infection even six months later,” said said Pulendran. Large late-stage trials of GBP510 in humans are underway.

AstraZeneca drug less protective against Omicron in transplant patients

AstraZeneca (AZN.L) antibody injections given to prevent COVID-19 in children and high-risk adults with weakened immune systems do not adequately protect organ recipients against the Omicron variant, researchers have found. researchers.

The drug, Evusheld, protected against the Delta variant in kidney transplant recipients, and lab test results released Monday show that Evusheld can neutralize Omicron in mice, including the highly contagious BA.2 version. But of the 416 kidney recipients treated with Evusheld after Omicron became the predominant variant, 9.4% developed symptomatic breakthrough infections, and one in three patients required hospitalization, the researchers reported. Saturday on medRxiv before peer review. Two patients have died from COVID-19. In laboratory experiments, researchers exposed the BA.1 version of Omicron which caused the winter spike in blood samples from 15 patients treated with Evusheld. None of the samples was able to neutralize the virus.

The United States Food and Drug Administration recently advised that higher doses of Evusheld are likely needed to prevent Omicron infections, and that patients who received the originally approved injections should receive booster doses. The researchers said kidney transplant recipients “should be advised to maintain health protection measures and undergo vaccine boosters.”

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Reporting by Nancy Lapid; Editing by Bill Berkrot

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