The Lancet Microbe

Scientists from Hokkaido University have shown that an antigen-based test for quantifying SARS-CoV-2 in saliva samples is simple, rapid, and more conducive for mass-screening.

Study shows that antibody longevity varies widely from 40 days to as long as several decades and not everyone who has recovered from COVID-19 is immune from reinfection. Individuals with low levels of neutralising antibodies may still be protected if they have robust T-cell immunity. Blood tests and a computer algorithm suggest annual vaccinations might be needed for some individuals to prevent future outbreaks of COVID-19.