The number of cases of a new sub-variant of Omicron in Northern Ireland have tripled in a week, new figures show.
A Department of Health briefing paper states that the BA-2 strain now accounts for 23.5% of Omicron cases - up from 7.7% the previous week.
The paper quotes ONS survey results which suggest that between 1 in 15 and 1 in 20 of the NI population tested positive for the virus in the week up to January 22.