The COVID-19 vaccine may need to be re-engineered to be effective against the new variant that has emerged in South Africa, says National Institute for Communicable Diseases (NICD) acting executive director Professor Adrian Puren.
The vaccine works by employing an antigen protein to train the immune system to produce antibodies to fight against the virus and prevent it from taking hold of the body. The new variant in South Africa, however, has mutated and the antibodies the vaccine produces may not be entirely effective against it.
The 501.V2 variant, which is dominant and driving the second wave in South Africa, was first detected in Nelson Mandela Bay before spreading to the Garden Route and KwaZulu-Natal, Health Minister Zweli Mkhize announced on December 18.
This new variant has three mutations, and has been detected in nearly 200 genomes collected in October and November. The higher viral load in swabs may translate to the higher efficiency of transmission.
Speaking to MyBroadband, Puren explains that two of the mutations caused two amino acid changes in the receptor membrane-binding protein that is important for antibody recognition.
“These changes, in theory, can affect antibody binding and it is currently under investigation to determine what effect if any these will have,” he said. “If this region is essential for antibody responses, then the antigen protein may have to be re-engineered to ensure efficacy,” he said.
The NICD also continues to investigate the relationship between the variant and re-infections, although at present there is no indication that it is associated with an increased risk.