Jan 12, 2022 - Health

Study: Omicron associated with 91% reduction in risk of death compared to Delta

Picture of a health worker taking care of a COVID patient
Nurses wearing PPE attend to patients in a Covid-19 ICU at Martin Luther King Jr. Community Hospital on Jan. 6, 2021 in Los Angeles, California. Photo: PATRICK T. FALLON/AFP via Getty Images

Omicron infections are associated with a 91% reduction in risk of death compared to the Delta variant, the director of the Centers for Disease Control and Prevention said Wednesday, citing a new Kaiser Permanente Southern California study.

The big picture: The study also showed that Omicron infections were also associated with a 74% reduction in risk of going to the ICU, as well as a 53% reduction in risk of being hospitalized, Rochelle Walensky said.

Details: The study, which is yet to be peer reviewed, looked at 52,297 Omicron cases and 16,982 Delta cases. Those involved tested positive in Southern California between Nov. 30, 2021 and Jan. 1, 2022.

  • It was also done with CDC collaboration and funding, Walensky said.
  • No patients with Omicron in the study required mechanical ventilation.
  • Additionally, those with Omicron had a shorter duration in hospital stay when compared to Delta patients: "The duration of hospital stays was approximately 70% shorter, with the median of stays being 1.5 days for Omicron, compared to about five days for Delta," Walensky said.
  • "Looking at all hospital admissions for Omicron, 90% of patients were expected to be discharged from the hospital in three days or less," she added.

Yes, but: "While we are seeing early evidence that Omicron is less severe than Delta, and that those infected are less likely to require hospitalization, it's important to note that Omicron continues to be much more transmissible than Delta," Walensky said.

  • This has resulted in "unprecedented daily case counts, sickness, absenteeism, and strains on our healthcare system," according to the CDC director.

NIAID director Anthony Fauci added that those who are vaccinated and boosted are much less likely to get severe illness from Omicron.

  • He said that as the virus is controlled — but not eradicated — "virtually everybody is going to wind up getting exposed and likely get infected," but the chances of getting sick is "very, very low" for those who are up to date with their inoculations.
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