According to a study by the National Institute for Communicable Diseases, which is a South African national public health institute:

  • Omicron infections had an 80% lower odds of being admitted to hospital
  • In those who are hospitalized, the risk of severe disease does not differ
  • When compared to Delta infections, omicron infections were associated with a 70% lower odds of severe disease
  • Estimates that after South Africa’s third coronavirus wave, 60%-70% of individuals had evidence of previous infection
  • Say unclear whether decreased severity in this wave is due to greater levels of immunity in the community or inherently decreased virulence
  • Study acknowledges that it was conducted when omicron numbers were ‘small’ and ‘patients with milder symptoms were more likely to be admitted’

The study can be found here