The world is ablaze with the news that the coronavirus has a new variant of concern — one that appears to be driving a dramatic surge in South Africa and offering a glimpse of where the pandemic might be headed. What do we know so far about how omicron differs from delta?
Little is known about the new variant, but the spike in South Africa suggests it might be more contagious, said Dr. Sikhulile Moyo of Botswana, the scientist who may have been the first to identify the new variant, though researchers in neighboring South Africa were close on his heels. It’s not clear if the variant causes more serious illness or can evade the protection of vaccines.
South African Health Minister Joe Phaahla noted that only a small number of people who have been vaccinated have gotten sick, mostly with mild cases, while the vast majority of those who have been hospitalized were not vaccinated, as has been the case with the delta variant.
South African scientists reported that omicron appears more likely than earlier variants to cause reinfections among people who have already had a bout with COVID-19.
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.
“Previous infection used to protect against delta, and now with omicron it doesn’t seem to be the case,” one of the researchers, Anne von Gottberg of the University of Witwatersrand, said at a World Health Organization briefing on Thursday.
The study also did not examine the protection offered by vaccination. Coronavirus vaccines trigger different layers of immune response, some to fend off infection and others to prevent severe disease if someone does become infected.
“We believe that vaccines will still, however, protect against severe disease,” von Gottberg said.