The National Center for Infectious and Parasitic Diseases (NCIPD) reports that 82 clinical samples with SARS-CoV-2 collected from 02 August – 02 September 2022 were analyzed by next-generation whole-genome sequencing. The clinical samples were collected in 17 different medical centers, from 16 districts of the country.

For the first time in Bulgaria, a sub-variant of Omicron BA.2.75 (a sub-variant of the BA.2 lineage) was identified, which seems more transmissible than BA.5. The World Health Organization (WHO) classified BA.2.75 as a variant of concern lineages under monitoring (VOC-LUM).

In all 82 clinical samples, the Omicron variant was identified. The Omicron subvariant ratio was as follows: BA.2.75 (2.4%), BA.4.x (3.7%), BA.5.x (72.0%) and BE.x/BF.x, which are a subvariant of BA.5 (22.0%).

Pangolin COVID-19 Lineage Assigner v4.1.1. program was used to define SARS-CoV-2 variants. An epidemiological analysis is being carried out.

For information on the classification of SARS-CoV-2 variants and sub-variants, please visit: https://cov-lineages.org/index.html
For an up-to-date classification of the variants of concern (VOC), please visit:
https://www.ecdc.europa.eu/en/covid-19/variants-concern
https://www.who.int/en/activities/tracking-SARS-CoV-2-variants/

The NCIPD continues to monitor the spread of SARS-CoV-2 in the country, with a focus on VOC, altered virulence and immunogenicity that are of increased public health importance.