COVID-19: scientists warn that reinfection with omicron appears to be more likely

Scientists from South Africa warn that reinfection among people who have already battled COVID-19 appears to be more likely with the new omicron variant than with previous mutations of the coronavirus.

A research group that has followed reinfections in South Africa reported an increase with the arrival of the omicron variant that had not been recorded in the country with the two previous variants, even with the more contagious delta variant.

The findings are preliminary and have not yet undergone scientific review. The researchers also did not specify how many of the reinfections were confirmed as omicron cases or if they had caused severe illness.

However, the peak of reinfection, by the time it occurs, reveals that there is substantial evidence that immunity from previous infection wanes, the scientists said.

“The previous infection used to protect against the delta variant and now with the omicron this does not seem to be the case,” said one of the researchers, Anne von Gottberg of the University of the Witwatersrand, in a briefing at the World Health Organization on Thursday. (WHO).

The study also did not analyze the protection offered by the vaccine. Vaccines unleash different layers of immune responses, some to prevent infection and others to prevent severe illness should someone become infected.

“However, we believe that vaccines still protect against severe disease,” stated Von Gottberg.

Scientists discovered the most recent variant just over a week ago in South Africa and Botswana, and it has now been found in several countries. Much remains unknown about the new variant, even if it is more contagious, as some authorities suspect, if it causes more severe disease or if it can evade the vaccine.

But it is important to know how much protection a previous infection offers, especially in parts of the world where much of the population remains unvaccinated.

The study indicates that the “omicron variant will be able to overcome natural and probably vaccine-induced immunity to a significant degree,” said Paul Hunter, professor of medicine at the University of East Anglia, in a written response to the study. To what extent “is not yet clear, although it is doubtful that this represents the full scope.”