Researchers with the University of Cambridge for the first time leveraged human data to quantify the speed of various processes in the brain that lead to Alzheimer’s disease.

The U.S. Centers for Disease Control and Prevention (CDC) on Sept. 24 backed a booster shot of the Pfizer and BioNTech Covid-19 vaccine for Americans aged 65 and older, adults with underlying medical conditions and adults in high-risk working and institutional settings.

Booster shots to bolster immunity against the coronavirus would be free and accessible, U.S. President Joe Biden said on Friday, one day after federal health agencies backed a booster rollout.

Three U.S. studies suggest Covid-19 vaccines offer strong protection against hospitalization and death, even in the face of the highly transmissible Delta variant, but vaccine protection appears to be waning among older populations, especially among those 75 and older.

The mRNA vaccine from Pfizer and BioNTech may be less effective than Moderna’s against the Delta variant of the coronavirus, according to two reports posted on medRxiv on Aug. 8 ahead of peer review.

Although there have been discussions about using different Covid-19 vaccines in combination, World Health Organization (WHO) chief scientist Soumya Swaminathan warned against it, calling it a “dangerous trend.”

The World Health Organization (WHO) forecasts that people most vulnerable to Covid-19, such as the elderly, will need to get an annual vaccine booster to be protected against variants, an internal document seen by Reuters shows.

Medicago and GlaxoSmithKline reported positive interim Phase 2 clinical trial safety and immunogenicity data for Medicago’s plant-derived Covid-19 vaccine candidate, which has been tested in combination with GSK’s pandemic adjuvant.

The first study to directly compare immune reactions between Pfizer’s and AstraZeneca’s Covid-19 vaccines found strong and broadly similar antibody responses in over-80-year-olds after a first dose of either shot, scientists said on April 14.

Covid-19 was the primary or contributing cause of 377,883 deaths in the United States during 2021, with a particularly high toll among the elderly, according to a government report released on March 31.