Omicron is as deadly if not more so than previous variants of the SARS-CoV-2 virus, a pre-print US study has found.
The study, which is yet to be peer-reviewed, counters previous indications that Omicron, while more transmissible, was less severe.
The study states that, after adjusting for other factors including comorbidities, vaccination status, and other demographics, the risk of severe COVID-19, hospitalization, and death, were nearly identical.
Previously, the WHO had also warned that the Omicron variant may be "less severe as a viral infection in an individual,” but that it is not a mild disease.
To test the assumption that previous waves of COVID were more severe the study's authors say they linked state-level vaccination data with quality-controlled electronic health records from the US healthcare system, including 13 hospitals in Massachusetts, USA.
"We then performed a weighted case-control study to compare risks of hospital admission and mortality across the SARS-CoV-2 waves in over 130,000 COVID patients...Our analysis suggests that the intrinsic severity of the Omicron variant may be as severe as previous variants."Excerpt
In a statement to Reuters, Dr. Arjun Venkatesh from the Yale School of Medicine, who wasn't involved in the study, called it unique and fairly strong.
'Omicron As Severe As Previous Variants, Possibly More'
The study also asserts that risk of hospitalization in the period of winter 2020-2021 was lower than risk of hospitalization during the Omicron period.
However, the study found no difference when comparing the adjusted risk of hospitalization during the Omicron wave to the spring months of 2021, or when comparing hospitalization risk during the Omicron wave to the Delta wave.
Limitations of The Study
Since the start of the pandemic, containment measures have grown and changed from quarantines, travel restrictions, and safe hand-washing practices, to include vaccinations, self- isolation, hospitalization, and preventive booster doses of vaccines.
However, the study failed to account for other treatments patients may have received, including monoclonal antibodies or antiviral drugs which have been proved to reduce hospitalizations, according to a statement from Dr. Venkatesh to Reuters.
He adds, "It's possible that if we didn't have these treatments available today, Omicron would be even worse."
The bottom line, Dr. Venkatesh says, is that the importance of vaccinations cannot be