CDC Study: Omicron Variant 91% Less Fatal than Delta

Hannah BleauJanuary 13, 2022

The omicron variant of the Chinese coronavirus is reportedly 91 percent less fatal than the delta variant, a Centers for Disease Control and Prevention (CDC) study released this week found.

The study, released January 11, 2022, seemingly affirmed that the omicron variant of the virus is significantly less severe than the delta variant.

“During a period with mixed Delta and Omicron variant circulation, SARS-CoV-2 infections with presumed Omicron variant infection were associated with substantially reduced risk of severe clinical endpoints and shorter durations of hospital stay,” the study found.

The study reads in part:

Within the subset of our cohort tested in outpatient settings, among whom prospective follow- up adverse outcomes was possible, Omicron variant infections were associated with 52%, 53%, 74%, and 91% reductions in risk of any subsequent hospitalization, symptomatic hospitalization, ICU admission, and mortality, relative to Delta variant infections. Median duration of hospital stay for patients admitted with symptomatic Omicron variant infections was approximately 70% (~3.4 days) shorter than that observed among patients with symptomatic Delta variant infections. Reductions in disease severity associated with Omicron variant infections were evident among both vaccinated and unvaccinated patients, and among those with or without documented prior SARS-CoV-2 infection. Prior vaccination against COVID-19 was associated with a dose-dependent lower risk of detection of the Delta variant as compared to the Omicron variant; likewise, Delta variant infections were less commonly detected among cases with documented prior SARS-CoV-2 infection.

“Thus, the finding of a reduction in severity of Omicron in patients with known prior infection is compelling evidence of an intrinsically less severe infection, rather than only different (more immune) persons becoming infected with the Omicron variant,” the study found, looking at 70,000 infected Californians and finding they were “less than half as likely to need hospitalization as those with Delta — and about 75 percent less likely to need intensive care,” according to the New York Post:

Even though the study looked at three times as many people with Omicron, none of them needed to go on a ventilator in the hospital — compared to 11 in the far smaller group with Delta.

Most encouragingly, just one of the 52,297 people infected with Omicron died — a reduction of 91 percent compared to 14 deaths in the 16,982 studied with Delta. It did not say how old those who died were, or if they were vaccinated.

This coincides with the narrative offered by public health officials and similar studies, both of which have pointed to the fact that the omicron variant of the virus is a more mild form of the illness.