New Research suggests Omicron Is Not as Severe As Delta
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People who get COVID-19 infections caused by the Omicron variant are less likely to need hospitalization, compared to those affected by the Delta variant, as per two new studies of a large size from the U.K. and South Africa.
These findings were released before peer review and provide evidence that Omicron although highly contagious, may cause less severe symptoms than its predecessors.
“This is helping to determine how severe Omicron is in comparison to Delta and Delta, and it appears that between 40 and 75% less risk for hospitalizations, adjusted to a variety of aspects, which are excellent,” said Eric Topol MD who is the editor-in-chief of Medscape and a cardiologist at Scripps Research Translational Institute La Jolla, CA.
The first analysis that was conducted by the World Health Organization Collaborating Centre for Infectious Disease Modelling and Imperial College London, found that overall, people infected by Omicron had around a 20% lower likelihood of needing any hospital care for their infections and 40% less risk of a hospital stay lasting more than a night when compared to those who were affected by Delta.
The patients who were infected again, which means they were infected again following an earlier COVID-19 infection, had a 50%-60% lower likelihood of needing hospitalization. This could be due to the advantage of having immunity to the same family of viruses.
The study covered all patients with polymerase chain reaction-confirmed COVID-19 in the U.K. during the first 2 weeks of December -about 56,000 Omicron cases and 269,000 Delta infections.
The second study was conducted by South African researchers at the National Institute for Communicable Diseases. It included more than 29,000 COVID-19 patients whose lab results strongly suggested Omicron infection. As compared to people who had the Delta variant, patients with presumed Omicron infections were around 70 percent less likely to develop severe illness.
The positive news for the population is encouraging, however the authors of the study cautioned that health systems are still under pressure.
“Given the fact that the Omicron virus is highly transmissible the Omicron virus, there is the potential for health services to be faced with increasing demand when Omicron cases continue to increase at the rate that has been observed in recent weeks,” said study author Neil Ferguson, PhD, who studies the way in which infectious diseases spread at Imperial College London.
The study’s authors claim that their findings are specific to the U.K. and South Africa, where substantial portions of the population have some immunity to past infections. In other words, they may not apply to countries where fewer have been vaccinated or have recovered from a bout with COVID-19.
Eric Topol, MD, editor-in-chief, Medscape and cardiologist, Scripps Research Translational Institute, La Jolla, CA.
Neil Ferguson, PhD, professor, Imperial College London.
MRC Center for Global Infectious Disease Analysis at Imperial College London: Report 50 – Omicron patients in England
MedRxiv: “Early assessment of the clinical severity of the SARS CoV-2 Omicron variant in South Africa.”