Brazzaville – Virus genome sequencing is playing a vital role in the efforts to tackle the COVID-19 pandemic. Sequencing enabled the world to rapidly identify SARS-CoV-2. Knowing the genome sequence allowed rapid development of diagnostic tests and other tools for the response.

Continued genome sequencing is enabling health authorities, governments and researchers to monitor the evolution of COVID-19 and adjust response accordingly.

In Africa, the World Health Organization (WHO) and the Africa Centres for Disease Control and Prevention in September 2020 launched network of 12 laboratories to reinforce genome sequencing of the virus. To date, 7891 sequences had been produced in the region, up from around 5000 in December 2020.

The emergence of new, more contagious SARS-CoV-2 variants is reinforcing the need to step up genomic surveillance. In Africa, South Africa detected the 501Y.V2 (also known as B1.351) variant in December 2020. The variant has been linked to the country’s recent surge in COVID-19 infections and it has now been identified in eight other African countries. Meanwhile, the variant initially identified in the United Kingdom (VOC202012/01) has been found in six countries in the continent.

WHO is working with countries to track and tackle new variants by helping build and boost the complex genomic surveillance capacities needed to detect and respond to new variants, shipping samples to sequencing laboratories and providing supplies, technical guidance and financial support to some countries for laboratory equipment.

Genomic sequences can help in the design of diagnostic assays, drugs and vaccines and in monitoring whether hypothetical changes in their efficacy over time might be attributable to changes in the virus genome. Analysis of SARS-CoV-2 virus genomes can therefore complement, augment and support strategies to reduce the burden of COVID-19.