Studies show that a fourth mRNA vaccine dose offers the elderly and other high-risk groups strong protection against hospitalization and death from COVID-19, but experts say benefits for other populations may be more limited.
Early reports that Omicron causes less-severe disease than Delta seem to be borne out, but it’s not yet clear to what extent that’s due to the variant itself versus the populations it’s infecting.
Experts have a decent grasp on how COVID-19 impacts cardiovascular health in the near term. The implications of long COVID, however, remain mysterious.
Recent studies have lent support for a variety of hypotheses explaining the debilitating symptoms affecting millions of people after SARS-CoV-2 infection.