ABSTRACT
The emergence of SARS-CoV-2 variants including the Delta and Omicron along with waning of vaccine-induced immunity over time contributed to increased rates of breakthrough infection specifically among healthcare workers (HCWs). SARS-CoV-2 genomic surveillance is an important tool for timely detection and characterization of circulating variants as well as monitoring the emergence of new strains. Our study is the first national SARS-CoV-2 genomic surveillance among HCWs in Lebanon. We collected 250 samples from five hospitals across Lebanon between December 2021 and January 2022. We extracted viral RNA and performed whole genome sequencing using the Illumina NextSeq 500 platform. A total of 133 (57.1%) samples belonging to the Omicron (BA.1.1) sub-lineage were identified, as well as 44 (18.9%) samples belonging to the BA.1 sub-lineage, 28 (12%) belonging to the BA.2 sub-lineage, and only 15 (6.6%) samples belonging to the Delta variant sub-lineage B.1.617.2. These results show that Lebanon followed the global trend in terms of circulating SARS-CoV-2 variants with Delta rapidly replaced by the Omicron variant. This study underscores the importance of continuous genomic surveillance programs in Lebanon for the timely detection and characterization of circulating variants. The latter is critical to guide public health policy making and to timely implement public health interventions.
Subject(s)
COVID-19ABSTRACT
As the novel coronavirus SARS-CoV-2 continues to spread in all countries, there is a growing interest in monitoring and understanding the impact of emerging strains on virus transmission and disease severity. Here, we analyzed SARS-CoV-2 genomic sequences reported in the Eastern Mediterranean Region (EMR) countries, as of 1 January 2021. The majority (∼75%) of these sequences originated from three out of 22 EMR countries, and 65.8% of all sequences belonged to GISAID clades GR, GH, G and GV. A delay ranging between 30-150 days from sample collection to sequence submission was observed across all countries, limiting the utility of such data in informing public health policies. We identified ten common non-synonymous mutations represented among SARS-CoV-2 in the EMR and several country-specific ones. Two substitutions, spike_D614G and NSP12_P323L, were predominantly concurrent in most countries. While the single incidence of NSP12_P323L was positively correlated with higher case fatality rates in EMR, no such association was established for the double (spike_D614G and NSP12_P323L) concurrent variant across the region. Our study identified critical data gaps in EMR highlighting the importance of enhancing surveillance and sequencing capacities in the region.