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.
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.
A preprint reports that the new SARS-CoV-2 variant multiplies faster in human bronchial tissue but slower in lung tissue than the Delta variant, potentially explaining how it’s spreading from person to person so quickly.
Experts have a decent grasp on how COVID-19 impacts cardiovascular health in the near term. The implications of long COVID, however, remain mysterious.