Little was known about the how protective the shots might be in people full data from clinical trials testing the BA.4 and BA.5 bivalent vaccines in humans hasn’t yet been made public.īut modeling data suggested that getting the boosters out in September could save tens of thousands of lives if the country had another winter surge, so the FDA authorized the shots, ahead of results from clinical trials, in order to get them to the public more quickly. When the US Food and Drug Administration issued emergency use authorizations for new bivalent Covid-19 vaccines from Pfizer and Moderna at the end of August, it did so on the basis of studies in mice and previous human trials with a different two-strain booster formulation.
Scientists say imprinting may complicate efforts to stay ahead of new variants as the coronavirus continues to evolve, and it adds urgency to the development of new vaccine technologies to fight the virus. Immunologists say a vaccine against two strains may not be better than a single strain shot because of a phenomenon called immune imprinting. David Ho, professor of microbiology and immunology at Columbia, whose team authored one of the studies. “We see essentially no difference” between the old boosters and the new about a month after the shot, said Dr. Hans Gutknecht/MediaNews Group/Los Angeles Daily News/Getty ImagesĬovid-19 vaccine study links side effects with greater antibody response
People receive booster shots during a COVID vaccination clinic at Villa Parke in Pasadena Friday, July 8, 2022.
0 kommentar(er)
