New Delhi: A preliminary study published by South African scientists suggests that the Omicron variant is three times more likely to cause reinfection as compared to previous Delta and Beta variant strains.
The findings of the study, which are yet to be peer-reviewed, collected data from the country’s health system and provided the first epidemiological evidence that Omicron is capable of evading immunity derived from the previous infection.
“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,” tweeted Juliet Pulliam, director of the South African DSI-NRF Centre of Excellence in Epidemiological Modelling and Analysis.
She said that it proves that Omicron has the advantage to infect those who had previously been infected with Covid-19 strains in the previous two waves.
“These findings suggest that Omicron’s selection advantage is at least partially driven by an increased ability to infect previously infected individuals,” she said.
She further added that now the study will need to focus on the data of the vaccinated people and the prevalence of Omicron strain in such individuals.
“We do not have information about the vaccination status of individuals in our data set and therefore cannot make any assessment of whether Omicron also evades vaccine-derived immunity,” she explained.
The paper was uploaded on a medical preprint server and has not yet been peer-reviewed.
This finding has important implications for public health planning, particularly in countries like South Africa with high rates of immunity from prior infection.
The country is witnessing a jump in recent cases. As of today, the cumulative number of COVID-19 cases identified in South Africa is 2,988,148 cases with 11,535 new cases reported on Thursday. With 44 deaths reported the total death tally has swollen to 89, 915 lives lost so far. The cumulative number of recoveries in South Africa now stands at 2, 850, 905 with a recovery rate of 95.4 per cent, as per the country’s health bulletin.