Detection of SARS-CoV-2 variants distributed from March 2020 to May 2022 and their effect on the infection severity in Iraqi population

Abstract

New SARS-CoV-2 variants appeared in late December 2020 as Mutations accumulated in the original virus. This study aimed to provide a local database about variants of COVID-19 circulating in the Iraqi population from 2020 to 2022 and the time of emergence of new strains each month since very few local studies have documented its existence in the country. Real-time reverse transcriptase polymerase chain reaction (rRT-PCR) assays were employed to 319 collected and analyzed nasal swabs to determine whether an infection had occurred. A sophisticated diagnostic kit that sorted the distinctive mutations was implemented to evaluate the variants. Results showed Younger patients were more likely to be infected with the Alpha variant (66 patients) than older people (43 patients). Additionally, patients with wild-type infestations had more robust viral load and lower Ct threshold values, culminating in an increase in severity during infection with wild-type virus 26/32 (81.250). Meanwhile, 65/109(59.63%) of patients infected with the Alpha variant developed severe and critical illness and 51/84(60.71%)were infected with Delta or Delta plus variants. In conclusion, the Alpha variant had the highest infection percentage of 109(46.6%), followed by Delta or Delta plus variant 84(26.33%), Beta or Gamma variants 47(20.1%), Omicron variant 46(19.6%), and finally wild-type virus of 32(13.7%). February 2020 witnessed a preliminary finding of the wild-type, while the Alpha variant emerged in December 2020, Beta/Gamma variances were recognized in December 2020, Delta/Delta plus variances began in April 2021, and the Omicron variant debuted in March 2022. Keywords: SARS-CoV-2, Mutation, rRT-PCR, Coronavirus disease 2019, TaqPath, cycle threshold (Ct) value