‘Immune Imprinting’: How It Affects Booster Shots — And Spoiled The Party

Fortune: High Hopes Were Riding On The New Omicron Boosters This Autumn. But They May Not Work Any Better Than The Original
Both papers cite “immune imprinting” as a potential reason for the new booster’s inability to outperform the original vaccine. It’s a phenomenon in which an initial exposure to a virus—say, the original strain of COVID, by infection or vaccination—limits a person’s future immune response against new variants. ... Immune imprinting “may pose a greater challenge than currently appreciated for inducing robust immunity” to COVID variants, the Harvard-affiliated authors wrote in their new paper. The authors of the other paper expressed the same concern, but cautioned that a second dose of the new booster may lead to a better antibody response. (Prater, 10/26)

CNN: Updated Covid-19 Boosters Offer Protection, But New Studies Suggest They Don't Offer An Edge Against Omicron 
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. 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. But 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. (Goodman, 10/26)

Boston.com: Dr. Ashish Jha: If You're Boosted, COVID Almost Definitely Won't Kill You. That's The Good News
Are you vaccinated and boosted? Your risk of dying from COVID-19 is “close to zero,” according to a top White House official — but studies show the newest booster may not be as effective as advertised. Dr. Ashish Jha, head of the White House COVID task force, said the U.S. has come a long way since the early days of the pandemic when thousands of people were dying daily from the virus. (McCourt, 10/26)

More on the spread of covid —

The Boston Globe: Meet The COVID-19 Variants That Experts Say Could Fuel A Surge This Winter
“It is this constant evolutionary arms race we’re having with this virus,” Jonathan Abraham, an assistant professor of microbiology at Harvard Medical School, told The Washington Post last week. Two particular strains have received an increased amount of attention recently, BQ.1 and XBB. (Finucane, 10/26)

The Washington Post: Still Afraid Of Covid: The People Who Are Still Isolating And Masking 
[Many] Americans are still going very far out of their way to avoid the virus. They don’t dine indoors at restaurants. They continue to practice social distancing. They wear highly protective masks if they must visit a doctor or stop at a pharmacy. Some are home-schooling their kids. Others are refusing to return to the office. They populate the dozens of social media groups whose members identify as “Still COVIDing.” Many of them would like the unmasked masses to know that this isn’t easy and that it’s only gotten harder. (McCarthy, 10/26)

Wired: Where Did Omicron Come From? Maybe Its First Host Was Mice 
It's one of the perplexing mysteries of the Covid pandemic: Where did Omicron emerge from, almost one year ago? The fast-moving, extremely contagious variant arrived just after Thanksgiving 2021, bristling with weird mutations. When scientists untangled the array, they found that Omicron wasn’t related to Delta or Alpha, the two waves that preceded it. Instead, its divergence from its closest common ancestor dated back more than a year, to the first few months of the pandemic—practically a geologic era in viral-replication time. (McKenna, 10/27)

Bloomberg: Covid-19 Forced Architects To Rethink Hospital Designs
UC Health is constructing an emergency department that can be easily switched to “pandemic mode,” which includes a separate entrance, triage space and treatment area for patients that may have respiratory illness. The hospital is also building a so-called alternate-care site, a separate area that can accommodate even more patients in the event of a pandemic or mass emergency. When it’s not being used for emergencies, the area can be used for other purposes, including as a public event space. Construction is expected to be completed by 2024. (Rutherford, 10/27)