SARS-CoV-2 Variants of Concern (VOC) alpha, beta, gamma, delta, and omicron coincident with consecutive pandemic waves in Pakistan

Document Type

Article

Department

Pathology and Laboratory Medicine

Abstract

Identification and monitoring of SARS-CoV-2 Variants of Concern/Interest (VOC/VOIs) is essential to guide public health measures. We report the surveillance of VOCs circulating in Karachi during the pandemic between April 2021 and February 2022. We screened 2150 SARS-CoV-2 PCR positive samples received at the AKUH Clinical Laboratories. VOC was identified using a PCR-based approach targeting lineage-specific mutations using commercially available assays. Of the SARS-CoV-2 PCR positive samples, 81.7% had VOC/VOI, while 18.3% were undetermined. Alpha variants were predominant at 82.5% and 40.3% of the cases in April and May 2021. Beta variants increased in May (29%) and June (42%) and then reduced to 6% by July. Gamma variant cases were at 14.5% and 9% in May and June, respectively. Delta variants first detected in May, increased to comprise 66% of all variants by July, remaining dominant in August, September, October, and November 2021 at 88%, 91%, 91% and 85% respectively. Omicron (BA.1) variants emerged in December, rising to 42% of cases with an increase to 81% by January 2022 and then reducing to 45% in February 2022. Delta variant prevalence was coincident with increased hospital admissions and mortality. The Omicron variant surge was associated with increased daily infections but limited COVID-19 severity. We highlight the predominance of the VOCs identified through a rapid PCR based approach. As this is important to inform a public health response, we propose that a mutation targeted approach can be a rapid, lower cost solution to aid tracking of known VOCs during pandemic waves.

Comments

Volume, issue and pagination are not provided by the author/publisher.

Publication (Name of Journal)

MedRxiv

DOI

10.1101/2022.05.19.22275149

Link to Full Text

Share

COinS