Between the lines: Thus far, it’s believed the Omicron subvariant is more transmissible — roughly 30% more than the original strain, WHO reported — but may not cause more severe disease than the original Omicron strain.

A preprint study out of Japan, which used animals with no immunity to COVID-19, indicated the BA.2 subvariant had features that make it capable of causing more severe illness.

However, several real-world data from pre-print studies, including one from South Africa, where immunity from vaccination or natural infection is high, has found “no difference in severity” between the original Omicron and the subvariant.

A pre-print study from Denmark found the subvariant is capable of reinfecting individuals who’d recently had COVID-19 from the Omicron or Delta strains, though the phenomenon was not common.