Covid-19 in Bulgaria: Omicron BA.5 lineage remains dominant – NCIPD

Bulgaria’s National Centre for Infectious and Parasitic Diseases (NCIPD) said on October 25 that it has completed the sequencing of 86 samples taken from Covid-19 patients in the country, which showed the BA.5 lineage of the Omicron strain and its subvariants remained dominant in the country.

All 86 samples, taken over a period of time ranging from September 11 to October 12 in 13 out of Bulgaria’s 28 districts, displayed evidence of the Omicron variant or one of its lineages.

The BA.5 lineage and its subvariants, which NCIPD collectively referred to as BA.5.x, is the main driver of the most recent coronavirus wave globally. Initially detected in South Africa in January 2022, BA.5 is categorised by the World Health Organisation (WHO) as a variant of concern lineage under monitoring.

The WHO defines a variant of concern lineage under monitoring as a subvariant that shows sign of “transmission advantage” to other lineages and has “additional amino acid changes that are known or suspected to confer the observed change in epidemiology and fitness advantage as compared to other circulating variants.”

BA.5.x was found in 61 cases or 70.9 per cent of the total sample size, compared to 77.7 per cent of the samples in the previous batch sequenced by NCIPD and announced on October 5.

The remaining samples showed evidence of several other lineages of the Omicron strain – 22 cases of the BE.x and BF.x lineages, which are a subvariant of BA.5, as well as one case each of of BA.4.6.1, BQ.1.1 and BM.1.1 lineages.

(Top photo: Military Medical Academy)

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The Sofia Globe staff

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