Abstract
Since the beginning of the SARS-CoV-2 pandemic, the emergence of multiple new variants posed an increased risk to global public health. The aim of this study is to investigate SARS-CoV-2 variants and possible transmission of variants of concern (VOCs) in Sierra Leone. A total of 65 nasal swab samples were collected from COVID-19 cases in Sierra Leone, among which 24 samples were collected during the second wave and 41 samples were collected during the third wave. Nanopore sequencing generated 54 SARS-CoV-2 whole genomes. The second COVID-19 wave was mainly caused by R.1 lineage while the third COVID-19 wave was dominated by B.1.617.2 lineage (Delta variant). The phylogenetic analysis suggested multiple introductions of SARS-CoV-2 Delta variant into Sierra Leone and subsequent local transmission in this country. Our findings highlight the importance of genomic surveillance of SARS-CoV-2 variants and the urgent need for implementation of strengthened public health and social measures (PHSM) to control the spread of virus variants.
Keywords: Delta variant; Lineage; SARS-CoV-2; Sierra Leone.
【저자키워드】 SARS-CoV-2, delta variant, Lineage, Sierra Leone., 【초록키워드】 COVID-19, public health, pandemic, SARS-CoV-2 pandemic, Nanopore, Genomic surveillance, variant, SARS-CoV-2 variant, variants of concern, Delta, B.1.617.2, Local, Transmission, delta variant, variants, Spread, Phylogenetic analysis, Surveillance, SARS-CoV-2 variants, implementation, VOCs, Lineage, nanopore sequencing, second wave, virus variants, nasal swab, genomic, COVID-19 cases, increased risk, global public health, COVID-19 case, measure, whole genomes, country, highlight, collected, caused, subsequent, suggested, the SARS-CoV-2, 【제목키워드】 SARS-CoV-2 variant,