Early studies show that Omicron can cause less hospitalization than previous variants

Early studies of Coronavirus test results in Johannesburg — South Africa have so far shown that patients infected with the Omicron variant may be hospitalized less frequently than patients infected with previous versions of the virus. Suggests.

The study, published Tuesday and based on just three weeks of data, also shows that the vaccine is less effective against mutants at high risk of breakthrough infections.

Epidemiologist Warns that more weeks of data will be needed to draw more solid conclusionsPartly because Omicron is not yet widespread and only a small proportion of infected people are ill enough to be hospitalized.

This study by a private health insurance company is a preliminary look at the course of the Omicron variety, but there are other possible explanations for the observed trends.

For example, the infection may appear mild overall, as more people in the current wave are protected to some extent from previous infections or immunizations. In addition, the average age of the subjects surveyed is 34 years, and adolescents generally tend to have mild symptoms. It may also make the Omicron infection look milder than it really is.

However, the findings reflect other studies showing that while new coronavirus cases are increasing exponentially, the trajectory of hospitalization is much flatter.

Snapshots of the first three weeks of each of South Africa’s four infectious waves show significantly less hospitalization in the Omicron-led fourth wave. In the Delta-led wave, there are 101 people per 1,000 people, compared to 38 people per 1,000 people. Studies have shown that if the beta variant was predominant, it would be 131 per 1,000.

Anecdotally, people admitted to the hospital had a much milder illness and a shorter length of stay, according to an account shared by doctors with researchers. The majority of patients in need of oxygen were not vaccinated, and only 16 percent of ICU admissions were vaccinated.

Studies have shown that the efficacy of the Pfizer-BioNTech vaccine appears to have diminished, with immunity between 80% in September and October after the delta wave subsided to only 33% in the Omicron wave.

“Omicrons significantly reduce the effectiveness of vaccines against new infections and can be exacerbated by reduced durability,” the authors conclude. Booster shots have increased the effectiveness of the vaccine against infection, but currently few booster doses are available in South Africa.

Nevertheless, studies have shown that the efficacy of the Pfizer-BioNTech vaccine for severe illness and hospitalization was approximately 70% after two doses.

The study also found an increased risk of reinfection with Omicron mutants and a decrease in immunity from previous infections. People infected with the delta variant of coronavirus had a 40% relative risk of being infected with the Omicron variant, but those infected during the beta drive wave in early 2020 could be re-infected with Omicron. Was 60%.

Initial assessment by South African epidemiologists Indicated Previous coronavirus infections appeared to provide little or no protection against Omicron.

“Hybrid immunity” means vaccination of people who are already infected with the virus, along with all existing non-pharmaceutical precautions, and highly contagious Omicron, said Dr. Ryan Noachi, CEO of He said it is likely to be the strongest defense against variants. Discovery Health, a private health insurance company that conducted the survey.

“Despite the reduced severity, the number of cases is so high that, frankly, we are concerned that the health care system may still be overkill,” Dr. Noach said.

The study tracked 211,000 test results and used anecdotal evidence from a private hospital in South Africa and a primary health care group. The findings are highly dependent on residents who can provide folk medicine. The majority of South Africans rely on state-owned hospitals and public clinics.

The study also stated that while few Covid-19 hospitalizations for children have been reported, children appear to be at greater risk during the current Omicron-led wave. However, some recent cases have been seen in children hospitalized for other reasons and may appear to be at higher risk than they really are.

Discovery’s actuary, Shirley Collie, said: Health that led the analysis.

South Africa’s experience is limited due to existing immunity and vaccination. Southern President Glenda Gray, who led another clinical trial conducted by Johnson & Johnson, said the Omicron mutation in countries with low vaccination rates, as more than 40% of adults are vaccinated. He said he had little understanding of how the body behaved. African Medical Research Council.