| 17 April 2024, Wednesday |

South Africa study suggests Omicron could displace Delta

According to South African scientists, the Omicron variation of the coronavirus might supplant the Delta variety because infection with the new variant enhances immunity against the older one.

The study only included a limited number of participants and was not peer-reviewed, but it discovered that persons infected with Omicron, particularly those who were vaccinated, gained greater immunity to the Delta version.

The study included 33 patients who were infected with the Omicron strain in South Africa, both vaccinated and unvaccinated.

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

“The increase in Delta variant neutralization in individuals infected with Omicron may result in decreased ability of Delta to re-infect those individuals,” the scientists who conducted the study said.

The results of the study are “consistent with Omicron displacing the Delta variant, since it can elicit immunity which neutralizes Delta making re-infection with Delta less likely,” they said.

According to the scientists, implications of this displacement would depend on whether or not Omicron is less pathogenic compared to Delta. “If so, then the incidence of COVID-19 severe disease would be reduced and the infection may shift to become less disruptive to individuals and society.”

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

According to an earlier South African study, there is reduced risk of hospitalization and severe disease in people infected with Omicron compared with the Delta variant, though the authors say 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 in some countries.

  • Reuters