The Omicron variant of Covid-19 appears to be reinfecting people at three times the rate of previous strains, experts in South Africa have said, as public health officials and scientists from around the world closely monitor developments in the country where it was first identified.
As the EU’s public health agency warned that Omicron could cause more than half of all new Covid infections in Europe within the next few months, evidence was emerging, however, that vaccines still appear to offer protection against serious illness.
According to new evidence collected in South Africa by its National Institute for Communicable Diseases (NICD) the latest epidemiological evidence suggests that Omicron can evade immunity from infection with earlier variants and is causing reinfections at three times previous rates.
The South African Centre for Epidemiological Modelling and Analysis along with the NICD said the latest findings “provide epidemiological evidence for Omicron’s ability to evade immunity from prior infection”.
“We believe that previous infection does not provide protection from Omicron,” said Anne von Gottberg, an expert at the NICD.
In mid-November South Africa was reporting about 300 Covid cases a day. On Wednesday, it reported 8,561 new cases, up from 4,373 the day before and 2,273 on Monday.
Outlining early research into the newly emerged variant, Von Gottberg said doctors were seeing “an increase for Omicron reinfections [of Covid-19]”.
She said: “We believe the number of cases will increase exponentially in all provinces of the country. We believe that vaccines will still, however, protect against severe disease. Vaccines have always held out to protect against serious disease, hospitalisations and death.”
Scientists from the same institute have said initial data suggests that Omicron may provoke less severe illness than previous variants although that may be skewed by the fact that many of the first Omicron cases have been identified in younger individuals or detected in very recently screened travellers.
But even as South Africans have rushed to get vaccinated – nudged by President Cyril Ramaphosa’s warning on Sunday that stricter lockdowns may have to be imposed if vaccination rates don’t improve – Aslam Dasoo, of the Progressive Health Forum, warned that the recent increase in vaccinations may be insufficient.
“It’s not enough to make a dent in the fourth wave,” he told the country’s News 24 news channel. “The test positivity rate was 1% last Monday. And it is now in the double digits. We are in the teeth of the fourth wave. Everyone you know is a potential risk to you,” he said.