Press Release No. 63/2022 COVID-19: ISS Flash Survey, on 6 September 100% Omicron, Predominance of Subvariant BA.5. Also Presence of BA.4, BA.2 and BA.1

ISS, 16 September 2022

In Italy on 6 September, the Omicron variant had an estimated prevalence of 100%, with BA.5 being the predominant subvariant. These are the results of the flash survey carried out jointly by the ISS and the Ministry of Health together with the regional laboratories and the Bruno Kessler Foundation.

For the survey, the laboratories of the Regions and Autonomous Provinces were asked to select sub-samples of positive cases and sequence the genome of the virus. The requested samples were chosen by the Regions/PPAAs randomly from among the positive samples, seeking to ensure geographic representation and, where possible, coverage of different age groups. In total, all the Regions/PPAAs with a total of 95 laboratories participated in the survey and 1065 samples were sequenced.

Estimated prevalence values were as follows:

BA.1 0.1% (range: 0% - 0.4%)

BA.2 1.1% (range: 0% - 14.3%)

BA 4 4.4% (range: 0.0% - 16.0%)

BA 5 94.4% (range: 84.0% - 100.0%)