The Department of Health today published the next in the series of weekly results from its COVID-19 Infection Survey (CIS). The findings set out in this report relate to modelled positivity estimates for NI for the week up to the 13 September 2022. The aims of the CIS are to estimate how many people have the infection and the number of new cases that occur over a given time as well as estimating how many people have developed antibodies to COVID-19.

The survey over time will help track the extent of infection and transmission of COVID-19 among people in the community population (those in private residential households).

Due to the relatively small number of tests and positive swab results within our sample, credible intervals are wide and therefore results should be interpreted with caution.

The World Health Organization (WHO) have defined names for variants of concern.

Currently, the variants under surveillance in the UK are:

The Cycle threshold (Ct) value reflects the quantity of virus (also known as viral load) found in a swab test. A lower Ct value indicates a higher viral load. The latest Ct values of coronavirus (COVID-19) positive tests, as well as analysis of the genetic lineages of coronavirus seen in the samples that are sequenced, are provided in the Coronavirus (COVID-19) Infection Survey: technical dataset.

Since the end of June 2022, the majority of COVID-19 infections in the UK have been Omicron variants BA.4 or BA.5, with BA.5 comprising 88.5% and BA.4 comprising 9.0% of all sequenced COVID-19 infections in the week ending 4 September 2022.

More information on how variants from positive tests on the survey are measured can be found in the ONS Understanding COVID-19 Variants blog and the Coronavirus (COVID-19) Infection Survey methods article.

The last published main variant analysis was included in COVID-19 Infection Survey, Northern Ireland: Weekly Report 8 July 2022. This showed a very high proportion of infections compatible with the BA.4 and BA.5 variants, so a breakdown of infections by variants is not included in this release. Infections by variant will continued to be monitored and analysis will be reintroduced when considered helpful.