The National Institute for Communicable Diseases (NICD) has released new information which suggests people can be re-infected with the new variant even if they had COVID-19 before.
The NICD explained people who have recovered from SARS-CoV-2 infection are usually protected from being infected a second time.
This is because they develop neutralizing antibodies that remain in their blood for at least 5 to 6 months, and maybe longer.
These antibodies bind to specific parts of the spike protein that have mutated in the new variant.
The institute said they now know that these mutations have allowed the virus to become resistant to antibody neutralization.
“The blood samples from half the people we tested showed that all neutralizing activity was lost. This suggests that they may no longer be protected from re-infection,” the NICD said.
In the other half, the levels of antibodies were reduced and which means the risk of re-infection is currently not known.
It is therefore important that people who have previously had COVID-19 continue to adhere to public health measures.
“Protecting ourselves through masks, regular washing or sanitising of hands, cleaning of surfaces, and social distancing remain the best defence against all SARS-CoV-2 viruses,” the NICD said.
New COVID-19 variant
The new COVID-19 variant was discovered through routine genomic surveillance of SARS-CoV-2 performed by a network of laboratories around the country.
The new variant is different from the others that were circulating in South Africa because it has multiple mutations in the spike protein.
The spike protein is the important part of the COVID-19 virus that binds to the receptor on the cells inside our body and that is also the main target for many of the antibodies produced during infection or after vaccination.
There is currently no clear evidence of the new variant results in more severe symptoms or a higher death rate.
Professor Salim Abdool Karim has, however, confirmed that the new variant is 50% more infectious than the first variant as it binds more readily to human cells.
He said the new variant contains changes in the charge and shape of the protein which means the virus and the spike protein can approach more deeply into the binding site.
This, in turn, means the new COVID-19 variant’s affinity and ability to bind into human cells is now stronger.
Karim added that researchers are still trying to establish whether current vaccines are effective against the new COVID-19 variant.