You can boost a vaccine’s effect with good moods and good friends

By Marta Zaraska

AS COVID-19 vaccine roll-out begins in earnest in many countries, there is an extra reason to be cheerful. Such an outlook, along with other personality traits and the kinds of social interactions we have, can enhance how our bodies react to immunisations.

“There is now a large literature that shows that these sorts of psychological factors influence how people respond to vaccinations as measured by magnitude of antibody response,” says Anna Marsland, a psychologist at the University of Pittsburgh in Pennsylvania.

In one of …