Detect the presence and manage the impact of SARS-CoV-2 variants
Widespread, standardised efforts to monitor and sequence SARS-CoV-2 samples will enable fast, efficient identification and management of viral mutations.
Arising mutations of the SARS-CoV-2 genome calls for global due diligence to closely monitor any variants to ensure diagnostic tests, vaccines, antiviral therapies and public health control measures remain effective.
In order to track variants, a portion of positive SARS-CoV-2 samples should be sequenced to detect novel variants or confirm known variants. Once the variant sequences are available, PCR genotyping assays have been developed to target particular mutations, thereby detecting the presence of variants in a region. This process constitutes the genomic surveillance programmes to detect, characterise and monitor SARS-CoV-2 variants over time.
How are SARS-CoV-2 variants classified?
The World Health Organisation (WHO) classifies variants into two groupings: Variants of Interest and Variants of Concern. Variants of Interest escalate to Variants of Concern after they reach certain criteria as listed by the table below:
Variants of Concern (VOC) 1
- Increase in transmissibility or detrimental change in COVID-19 epidemiology;
- Worsening in the severity of the disease or changes in symptoms;
- Reduced efficacy of public health and social measures, diagnostics, vaccines and therapeutics.