Two doses of the BioNTech/Pfizer vaccine provide 70% protection against hospitalizations with the Omicron coronavirus variant, according to the first real analysis of protection against severe illness with the new virus strain in South Africa. .
But the protection against Omicron was lower than the 93% protection against the Delta variant, said a report from Discovery Health, the largest private healthcare provider in South Africa.
The study also showed that the rate of severe illness during the early stages of the country’s Omicron wave was lower than during the same period in previous surges. The study was not submitted for peer review.
The researchers found that the risk of a Covid-19-positive adult being hospitalized since 15 November was 29% lower than in the first wave in South Africa. This reduction in severity was maintained after adjusting for age, immunization, and prior infection, as well as baseline health.
The findings demonstrate that, although the number of Omicron infections is likely to rise particularly when it is on hold, the rates of those cases developing severe disease will be lower than those seen over the past 20 months. The successive layers of immunity acquired through infection and vaccination probably play an important role.
Professor Glenda Gray, president and chief executive officer of the South African Medical Research Council (SAMRC), says that very high levels of pre-existing infections, combined with increasing vaccination coverage, have can create a wave of seemingly “no more deaths and hospitalizations”.
“We don’t think it’s a question of virulence,” she added.
Dr Simon Clarke, associate professor of cellular microbiology at the University of Reading, stressed that the increase in Omicron’s infectivity “could easily outsurp” the decrease in disease severity seen observation in the study.
“Similarly, the mass illness of those who are not sick enough to go to the hospital, but who need to recuperate at home, can cause significant shutdowns of public services and slow economic activity. again”.
One area of concern is the rising rate of coronavirus hospitalizations among children. The study found that, while rates in recent weeks were higher than in previous episodes, many of these cases were accidental hospitalizations in which patients tested positive only after hospitalized for another reason, and most children hospitalized with Covid-19 symptoms recover in about three. day.
The authors caution, however, that all of their findings are stub. They said the age profiles of Discovery Health members and the broader South African population may limit the extent to which their conclusions would translate to other countries.
Shirley Collie, head of health analytics at Discovery Health, said: “This is preliminary data and needs to be carefully monitored.
Research has proven previous findings of SAMRC that Omicron is more likely than other variants to re-infect people who have previously had coronavirus, especially when the infection was months earlier.
Among those infected during the first wave in South Africa in mid-2020, the relative risk of re-infection with Omicron was 2.5 times higher than that of reinfection with another variant.
