Tracking SARS-CoV-2 variants is important for disease monitoring and assessing the evolution of the virus. Additionally, variant monitoring is also important for accurate detection of SARS-CoV-2 lineages, which helps with predicting the prognosis of disease and making treatment decisions. Until recently, assigning epidemiological SARS-CoV-2 lineages has been challenging due to the small number of sequenced SARS-CoV-2 genomes. To address this issue, Akçeşme et al. (2022) set out to sequence SARS-CoV-2 genomes in mass and analyze epidemiological SARS-CoV-2 lineages in Turkey. The team collected nasophyrangeal swab samples from PCR confirmed, SARS-CoV-2 positive patients distributed in 10 distinct cities of Turkey. After RNA extraction and next-generation sequencing of viral genetic material, 1346 SARS-CoV-2 genome samples were uploaded to the CosmosID SARS-CoV-2 Strain Typing Analysis Portal (CosmosID, Germantown, MD). The results follow:
- 60 SARS-CoV-2 lineages were detected in Turkey
- The lineage B.1.617.2 is the dominant lineage in Turkey
- 29 lineages compose 10 different clades
- The clade 20A, including the lineage B.1.617.2, constitutes 77% of all infections between ages 18-45, but ~50% in +65 age cohort
- All clades are predominantly identified in the age group 18-45, yet some lineages seem to have age group preferences
- Infection clades are associated with patient outcome
- Monthly clade distributions illustrate that a new dominant clade rapidly sweeps the distribution
Key Findings:
Results of the study illustrate that age and disease outcome are associated with the lineage of the SARS-CoV-2 virus. The COVID-19 epidemiological setting in Turkey emerges to be similar to that of the global with different lineages in different cities and similar predominant SARS-CoV-2 lineages as B.1.617.2 or B.1.1.7.
