SA study suggests Omicron enhances neutralising immunity against Delta

Research by SA scientists suggests Omicron infection enhances neutralising immunity against the Delta variant of the coronavirus.

The study, which has not been peer-reviewed, found that people who were infected with Omicron, especially those who were vaccinated, developed enhanced immunity to the Delta variant.

The analysis enrolled 33 vaccinated and unvaccinated people who were infected with the Omicron variant in SA.

While the authors found the neutralisation of Omicron increased 14-fold over 14 days after the enrolment, they also found there was a 4.4 fold increase of Delta virus neutralisation.

“The increase in Delta variant neutralisation in individuals infected with Omicron may result in a decreased ability of Delta to reinfect those individuals,” the scientists said.

Alex Sigal, a professor at the Africa Health Research Institute in SA, said on Twitter on Monday that if Omicron was less pathogenic, as it looked from the South African experience, “this will help push out Delta”.

According to an earlier South African study, there is reduced risk of hospitalisation and severe disease in people infected with the Omicron coronavirus variant compared with Delta, though the authors said some of that is likely due to high population immunity.

The Omicron variant, first detected in southern Africa and Hong Kong in November, has since spread worldwide and threatened to overwhelm hospitals and disrupt travel plans.

Reuters