The risk of hospital admission during the country’s fourth wave, when Omicron spread rapidly, was 29 percent lower than during its first wave in early 2020. And patients infected between mid-November and early December were also less likely to end up in intensive care units, experts said. They estimated that two doses of the Pfizer vaccine were still offering 70 percent protection against hospitalisation, despite a rise in breakthrough infections.
The research is by private health insurance administrator Discovery Health, with South Africa’s Medical Research Council (SAMRC). However, Prof Chris Whitty told Cabinet ministers yesterday that a “significant increase in hospitalisations” from Omicron was expected in Britain.
The Prime Minister’s spokesman reported that the Chief Medical Officer “said it was too early to say whether cases were reducing or plateauing in South Africa but there was no reliable evidence from South African scientists of a peak in case rates, and added that it also remained too early to say how severe the Omicron variant was”.
South African scientists were the first to raise the alarm over Omicron in November, as the country saw a rapid surge in infections. Discovery Health CEO Dr Ryan Noach said: “Epidemiological tracking shows a steep trajectory of new infections, indicating a rapid spread of Omicron, but so far with a flatter hospital admission trajectory possibly indicating lower severity.”
Dr Noach cautioned that all the data was preliminary and factors including high levels of previous infection in South Africa may have skewed the results.
Children seem to be a fifth more likely to be hospitalised with Omicron, while risk of reinfection with the latest variant was much higher than for previous strains, causing more breakthrough infections among the vaccinated.
For two doses of the Pfizer/ BioNTech vaccine, protection against infection plummeted from 80 per cent with Delta to just 33 per cent with Omicron. But the jabs were estimated to have offered 70 per cent protection against hospitalisation as Omicron cases rose. This compared with 93 per cent against Delta.
SAMRC president Professor Glenda Gray said: “It is extremely important to be able to demonstrate to the public that in a real-world setting, in the presence of a highly transmissible new Covid-19 variant, the Pfizer-BioNTech vaccine gives good protection against severe disease and hospitalisation.” Addressing UK MPs, Dr Angelique Coetzee, chairwoman of the South African Medical Association, said the findings lined up with what she had seen – saying many cases were mild and symptoms in vaccinated people were “less severe or intense than in the unvaccinated”.
But Dr Simon Clarke, of the University of Reading, argued that Omicron is still dangerous, adding that its high transmissibility “could deliver a much more significant impact to society and the NHS than previous waves”.