![]() Paul Offit, a vaccine scientist and professor of pediatrics in the Division of Infectious Diseases at the Children’s Hospital of Philadelphia and a member of the advisory committee, emphasized before the meeting that it’s important to discuss who needs an updated vaccine this fall. He noted that the FDA will need to work with the US Centers for Disease Control and Prevention to make a recommendation soon about whether eligible people should continue getting the currently available vaccines.ĭr. Peter Marks, director of the FDA division that oversees vaccines, suggested that the updated vaccines could be available around September, acknowledging that there is still some uncertainty around timelines. The agency isn’t bound to the outcome of the committee’s vote but takes it into consideration. The FDA asked its advisers to discuss the specific strain to choose for the vaccine update but to vote only on whether the vaccine should target a single XBB strain. The World Health Organization said in May that its advisory group recommended that updated vaccines target an XBB strain of the virus and leave out the original version. The FDA appears set to follow that advice, which would also keep it in step with international guidance. “That’s why we made the recommendation that if you want to broaden out your antibody responses, it’s best to remove the ancestral spike in future vaccines,” Ho said. His research has shown that the bivalent boosters, which are designed to target both the original strain and the BA.4 and BA.5 versions of Omicron, produce an immune response that’s similar to a boost with the original vaccine alone – but that infection with the BA.5 strain, encountering the immune system without the older strain alongside it, improves the immune response against newer strains of the virus. It’s a phenomenon known as immunological imprinting, Ho said: The immune system reacts best to strains it already knows, so showing it the old strain along with new ones hampers the immune response to the new, more relevant strains. David Ho, a professor of microbiology and immunology and director of the Aaron Diamond AIDS Research Center at Columbia University whose research is cited in the FDA’s briefing documents. ![]() “Your immune response likes to react to what it’s seen before,” said Dr. This single-strain or monovalent vaccine would drop protection against the original strain of the virus that emerged in China in late 2019, a version that experts don’t expect to return and whose continued inclusion in vaccines may contribute to lower efficacy against newer strains. What does the end of the Covid-19 national emergency mean? Our medical analyst explains (AP Photo/Steve Helber, File) Steve Helber/AP The Biden administration will end most of the last remaining federal COVID-19 vaccine requirements next week when the national public health emergency for the coronavirus ends, the White House said Monday, May 1, 2023. FILE - Pfizer, left, and Moderna bivalent COVID-19 vaccines are readied for use at a clinic, Nov.
0 Comments
Leave a Reply. |