Those who received at least two vaccinations and had fewer repeat infections, and those who were infected with later variants of SARS-CoV-2 had lower measures of cognitive decline.
The length of time you spend around a person with COVID-19 seems to heavily influence your likelihood of getting sick, according to a recent Nature study that has been peer-reviewed but not fully edited. Most exposures that result in transmission last at least an hour, if not much longer, the researchers say.