There's a new covid-19 sub-variant on the loose, experts have warned, as positive cases rise once again among the elderly.
The new strain has gained the colloquial name "stealth omicron" as it is more difficult to differentiate from past variants than omicron itself was. This strain, officially named the BA.2 variant, is very closely related to the first omicron strain, BA.1, but lacks a telltale genetic sign that made omicron easy to differentiate from past variants such as beta and delta.
Coronavirus cases are substantially lower now than they were during their peak in January, but cases among the over-55s are slowly beginning to increase again. Researchers say this could be due to numerous factors, including more mixing between the age groups since restrictions eased and the waning of the protection offered from vaccines.
