During Omicron, disease severity appears to be lower than during other periods of high transmission, according to CDC study

During a period when the Omicron coronavirus variant was dominant, severe outcomes for patients hospitalized with Covid-19 -- including ICU admission, ventilator use and death -- were less common than during Delta or the first winter surge, according to a study published Tuesday by the US Centers for Disease Control and Prevention.

Also, although the daily average of new cases and hospital admissions reached record highs during the Omicron period, there were fewer hospitalizations and fewer deaths for every 1,000 cases than during the Delta period or the first winter surge. These ratios compared the peaks of each metric within each period analyzed.

Severity of disease appears to be lower during the Omicron period due to a combination of factors, according to the researchers: higher vaccination coverage including boosters, immunity acquired from previous infection and potentially lower virulence of the Omicron variant.