Study finds Omicron variant of Covid is as severe as Delta variant

Back in November last year when the Omicron variant of COVID-19 was first identified, many experts and scientists claimed that the variant is mild and not as dangerous as its predecessors Delta and Alpha.

Now, a study led by Massachusetts General Hospital and Harvard Medical School has found that the risk of hospitalisation and mortality between Omicron and previous waves was "nearly identical".

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"Our analysis suggests that the intrinsic severity of the Omicron variant may be as severe as previous variants."

The variant was first detected in South Africa and previous studies have reported that it is more transmissible than other variants.

Conducted in multiple countries, these studies also claimed that the variant is less severe, leading to a lower number of hospitalisations and deaths.

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Scientists integrated state-level vaccination data with quality-controlled electronic health records from a large healthcare system in Massachusetts, which included 13 hospitals, for the study.

The researchers then conducted a weighted case-control study on approximately 130,000 Covid patients to examine the risks of hospitalisation and fatality across the SARS-CoV-2 waves.

Previous waves appeared to have higher unadjusted rates of hospital admission and mortality than the Omicron period.

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However, after controlling for variables such as demography and vaccination status, the researchers concluded that "the Omicron variant was as deadly as previous SARS-CoV-2 waves," according to the study's authors, which included MGH's Zachary H. Strasse.

While previous reports have made note of Omicron's vaccine evading properties this new study provides evidence that the vaccines helped people escape its worst effects.

(With inputs from agencies)