Getting infected twice with two different Omicron Covid-19 sub-variants is possible, but rarely happens, a Danish study has found.

In Denmark, a more infectious sublineage of the Omicron coronavirus variant known as BA.2 has quickly dethroned the “original” BA.1 variant, which is the most common worldwide, but it has remained unclear whether a person could get infected by both variants.

A new study, led by...