Figuring the characteristics of the Delta variant SARS-CoV-2 gene mutations in an Indonesian hospital: a descriptive study

Aim: Coronavirus disease 2019 (COVID-19) is a respiratory infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The SARS-CoV-2 has undergone several mutations, and ultimately, Indonesia was designated the Asian epicenter of the pandemic in 2021 due to the emergence of Delta variant SARS-CoV-2. Therefore, this study aimed to determine the characteristics of the Delta variant SARS-CoV-2 gene mutations. Methods: This is a cross-sectional descriptive study to determine the mutation characteristics of the Delta variant SARS-CoV-2 with data collected from patients’ medical records and whole genome sequencing (WGS). Results: The forty-nine patients who contracted the Delta variant SARS-CoV-2 were mainly aged 31−45 years and female. Four sublineages were identified, namely AY.23 (69.39%), AY.24 (22.45%), B.1.617.2 (6.12%), and AY.62 (2.04%), with fever and malaise being the most common clinical manifestations (79.60%). Furthermore, the spike (S) protein was most frequently mutated (12 mutations), with mutations in the Delta variant SARS-CoV-2 membrane (M) protein, nucleocapsid (N) protein, open reading frame (ORF), and nonstructural protein (NSP) also identified. Conclusions: The most common Delta variant SARS-CoV-2 sublineage in the current study cohort was AY.23, with the S protein being most frequently mutated. Continuous genomic surveillance is required to contain future outbreaks or infection waves, especially during the COVID-19 pandemic.