Omicron 3 Times More Likely To Cause Reinfections Compared To Other Covid Strains: Report

The findings provide the first epidemiological evidence about Omicron’s ability to evade immunity from earlier infection.

Omicron variant is three times more likely to cause reinfections compared to the Delta or Beta strains | Representational image (Getty)

New Delhi: The Omicron variant is three times more likely to cause reinfections compared to the Delta or Beta strains, suggests a preliminary study by South African scientists published Thursday. The paper is yet to be peer-reviewed and was published on a medical preprint server.

The study was conducted based on the data collected by the country’s health system. The findings provide the first epidemiological evidence about Omicron’s ability to evade immunity from earlier infection, AFP reported.

35,670 Suspected Cases Of Reinfections

As of November 27, there were 2.8 million individuals with positive tests. Out of these, there were 35,670 suspected reinfections. When a person tests positive twice with a gap of 90 days, the case is considered reinfection.

Juliet Pulliam, Director of the South African DSI-NRF Centre of Excellence in Epidemiological Modelling and Analysis, tweeted that recent reinfections have occurred in individuals whose primary infections occurred across all three waves, with the most having their primary infection in the Delta wave.

Pulliam said the authors could not access to what extent Omicron evades vaccine-induced immunity because the authors did not have information about the vaccination status of individuals.

"Data are urgently needed on disease severity associated with Omicron infection, including in individuals with a history of prior infection," the AFP report quoted Juliet Pulliam.

The research was praised by Michael Head, a scientist at the University of Southampton. He said the fact that "immunity from previous infections being relatively easily bypassed" is a "false alarm" is looking less and less likely, the report stated.

There has been an exponential rise in Covid-19 cases in South Africa following the detection of the Omicron variant. South Africa was reported around 300 cases a day in mid-November. However, the country reported 2273, 4373, and 8561 new cases on Monday, Tuesday, and Wednesday respectively.