Study suggests past COVID infection may not fend off omicron

South African scientists are warning that the new omicron variant may be causing more reinfections among COVID-19 survivors than earlier virus mutants

THE HAGUE, Netherlands -- South African scientists are warning that reinfections among people who’ve already battled COVID-19 appear to be more likely with the new omicron variant than with earlier coronavirus mutants.

A research group has been tracking reinfections in South Africa and reported a jump with the arrival of omicron that they hadn't seen when two previous variants, including the extra-contagious delta variant, moved through the country.

The findings, posted online Thursday, are preliminary and haven't yet undergone scientific review. Nor did the researchers say what portion of the reinfections were confirmed as omicron cases — or whether they caused serious illness.

But the timing of the reinfection spike suggests that omicron “demonstrates substantial population-level evidence for evasion of immunity from prior infection," they wrote.