Targeted ORF8-N Sanger Sequencing as a SARS-CoV-2 Surveillance Contingency During Supply Shortages.

BACKGROUND

Global shortages of next-generation sequencing (NGS) reagents threatened SARS-CoV-2 genomic surveillance in low- and middle-income countries during the COVID-19 pandemic.

METHODS

During the 2021 NGS reagent shortages, we implemented targeted ORF8-N Sanger sequencing for SARS-CoV-2 variant surveillance in Brazilian public health laboratories.

RESULTS

In silico analysis of whole-genome sequencing (WGS)-derived SARS-CoV-2 genomes from the Federal District, Brazil, showed that the ORF8-N target discriminated the major 2021 lineages (Gamma and Delta) and enabled analysis of ˃300 samples despite constrained NGS access.

CONCLUSIONS

Targeted ORF8-N Sanger sequencing was a useful temporary contingency during NGS reagent shortages but offered lower phylogenetic resolution than WGS.