Most cases of Omicron in South Africa are mild, the head of its medical association has told British MPs, as new real-world data suggests two doses of the Pfizer vaccine offer 70% protection against hospital admission.
Dr Angelique Coetzee, chairwoman of the South African Medical Association, told the Commons Science and Technology Committee she agrees with a new study from the South African Medical Research Council suggesting that Omicron may be 29% less severe than the first wave of infection that swept the country.
She said “we don’t have all the answers” but the clinical picture so far is that people are mostly suffering mild illness from Omicron.
Dr Coetzee said some people are getting breakthrough infections if they are vaccinated or if they have had Covid before, but cases seemed to be milder, especially for the vaccinated.
“On a hospital level… between 88% to 90% (of people) are unvaccinated.”
She said that in hospitals it is hard to differentiate between those patients with the Delta variant and those with Omicron, but that intensive care units “are still not overwhelmed”.
It came as a new study, based on preliminary data from the first three weeks of the Omicron surge in South Africa, suggested that two doses of the Pfizer/BioNTech jab makes vaccinated people 70% less likely to be admitted to hospital compared with those who are unvaccinated.
This is lower than the 93% protection the jabs gave during the Delta wave, but still offers a good degree of protection.
Overall, adults infected with Omicron were 29% less likely to need hospital care compared with earlier variants, the study found.
Younger age groups were slightly less likely to go to hospital than older people, though experts think this may be due to waning immunity in older people who were given their vaccines first.
The study was in a population where most had had a previous Covid infection – as high as 70% of people in some areas of Gauteng province.
South Africa also has a high burden of TB and HIV.
The study was based on 211,000 positive coronavirus test results in the three weeks to December 7, including 78,000 thought to be Omicron.
Overall, 41% of those testing positive had received two doses of the Pfizer/BioNTech vaccine.
Dr Michael Head, senior research fellow in global health at the University of Southampton, said the analysis covers just three weeks of data and “it is important to avoid inferring too much right now from any national scenario”.
He added: “For example, the narrative around South Africa is that Omicron may be much milder, whereas reports out of Denmark broadly suggests the opposite.
“This reflects the uncertainty of new data. Within that, factors include the different levels of exposure to Covid-19 and previous infection, levels of vaccination and potential waning of immunity, and also age ranges infected thus far.
“We know that Covid-19 is very adept at moving from younger to older populations within a few weeks.
“Is Omicron milder or more severe than Delta? Time will tell. The world’s finest scientists, including many in the global south such as in South Africa, will find out.
“For now, national-level decision-makers have to consider that discretion is the better part of valour.”