PICOBOO randomized trial, evaluating second boosters after mRNA priming. 1) novavax is more durable 2) mRNA vaccines have higher antibody responses 3) novavax has fewer side effects
Pfizer antibody levels drop around 40% between 1 month to 3 months post vax. Moderna is less, w/ a 14% drop in younger adults, 26% decline in older adults. Novavax had only a 3% decline in younger adults and 17% in older adults.
Study at KU Leuven on hamsters finds that immunity from XBB.1.5 COVID-19 vaccine favors the original strain, limiting antibody response to newer variants like JN.1.
Highlights the challenge of updating vaccines for evolving SARS-CoV-2.
While effective at preventing severe COVID-19, the protection you get from mRNA vaccines can fade within months.
Long-lasting immune cells that fight SARS-CoV-2 aren't usually found in mRNA-vaccinated people, unlike the immune cells for tetanus and flu.