GENETIC SIGNIFICANCE AND TRACKING OF CIRCULATING SARS-COV-2VARIANTS IN THE REPUBLIC OF MOLDOVA

Tracking the circulating variants of the SARS-CoV-2 virus and identifying new genetic variations provide a high-resolution perspective with many advanced applications, ranging from developing diagnostic tests and vaccines to real-time data for public health measures. This study aimed to investigate and assess the genetic variants of SARS-CoV-2 circulating in the Republic of Moldova to improve COVID-19 response strategies. A retrospective descriptive study was carried out in the National Public Health Agency virology laboratory. The study analysed 417 biological samples collected from patients infected with COVID-19, with SARS-CoV-2 presence confirmed by molecular biology techniques (Reverse transcription polymerase chain reaction (RTPCR)). Viral fragment sequencing was performed via the Ion Torrent Genexus sequencer, Pangolin, and GISAID (Global Initiative on Sharing All Influenza Data) software. The Omicron variant underwent multiple genetic changes throughout 2022. Thus, these changes were divided into four distinct periods of SARS-CoV-2 genome evolution. The first period (January–March) was characterized by the predominance of BA.1* and its subvariants; the second period (March–June) by the predominance of the BA.2* sublineage and its subvariants; the third period (June–October) by the predominance of BA.4*/BA.5* and their subvariants; and, finally, in the fourth-period various sublineages, including BQ.1*, BN.1*, CC.1*, and XBB.1.5, became predominant. In conclusion, the implementation of advanced SARS-CoV-2 genome sequencing technologies in the Republic of Moldova has proven the importance of detecting novel viral mutations and their impact on the epidemic progression of the COVID-19 infection.