A preliminary study from the United States of nearly 70,000 people positive for COVID-19 showed a substantially reduced risk of hospitalization and death from the omicron variant even after controlling for increasing immunity levels in the population.
According to the study, people infected with Omicron were half as likely to be hospitalized, about 75% less likely to need intensive care, and 90% less likely to die than people infected with the previously dominant delta variant.
Of some 50,000 people infected with Omicron, none ever needed a respirator.
Hospital stays lasted an average of 1.5 days for Omicron compared to five days for delta, and 90% of omicron patients were discharged in three days or less.
The analysis was conducted with data from the Kaiser Permanente hospital system in Southern California, which served about 4.7 million people between December 1, 2021, and January 2, 2022, when both strains were circulating. Widely.
The findings are based on the accumulation of population-level research from countries such as South Africa and Great Britain and animal and cell-based tests, which have found that Omicron replicates better in the upper respiratory tract than the lungs.
"This study controlled for important key parameters such as age, gender, prior Sars-CoV-2 infection, prior vaccination, and comorbidities," CDC Director Rochelle Walensky told reporters in a call Wednesday.
Thus, the results suggest that Omicron is "inherently less severe than delta." The reductions seen in severe cases are not just the result of more people being vaccinated and infected over time, according to the article.
Although the study observed a reduction in the vaccine's efficacy against omicron infection, it also found substantial continued protection against serious outcomes.
Walensky cautioned that the results should not lead to complacency, as Omicron's extreme transmissibility is still testing America's already overburdened healthcare system and its exhausted healthcare workers.
This new article, which has not yet been peer-reviewed, was written by researchers at the University of California, Berkeley, Kaiser Permanente, and the Centers for Disease Control and Prevention (CDC).
Currently, the United States is registering an average of 750,000 cases per day, around 150,000 total hospitalizations for covid, and more than 1,600 deaths daily.
President Joe Biden's chief medical adviser, Anthony Fauci, predicted Tuesday that "omicron, with its extraordinary and unprecedented degree of transmissibility efficiency, will ultimately hit just about everyone."
But he added that after the country emerged from its current wave, it would transition to a future of coexistence with the virus, with covid vaccines that would moderate-severe disease for the majority and effective treatments available for the most vulnerable.