Is Omicron More Fatal Than The Seasonal Flu?

As the Omicron variant of COVID-19 swept over the world at the end of 2021 to become the dominant strain in most countries, there has been a collective sigh of relief over its milder symptoms and reduced ability to hospitalize and cause death, compared to earlier strains (via Reuters). But experts have been warning that we should not let down our guard, as much of Omicron's purported mildness in the population could be due to immunity already gained by prior infection and vaccination rather than any lower potency of the variant itself (via Harvard T.H. Chan School of Public Health).

A report released by a panel of Japanese government health officials this week is lending more weight to the advice that we should take Omicron seriously (via The Mainichi). By examining mortality records of patients hospitalized for both Omicron and the seasonal flu, Japanese health officials were able to infer that the fatality rate for Omicron, 0.13%, is significantly higher than that of the seasonal flu: 0.006–0.09%. With Omicron still transmitting at high levels around the globe, this data reinforces many health experts' call to not consider the pandemic over just yet and keep practicing preventative measures. Even worse, Japanese officials have identified a new subvariant of Omicron.

According to the Japanese health officials, Omicron is still on an upward trajectory in Japan and is quickly being replaced with the new BA.2 subvariant, dubbed the "stealth Omicron," which is predicted to replace the original Omicron and account for 74% of the country's cases by April 1 (via The Mainichi). Because their fatality rate calculations that showed Omicron more fatal than the flu were based on the original Omicron strain, the new fatality rate for the "stealth" variant may be even higher.

According to U.S. News & World Report, the case rates of the "stealth" variant are doubling each week in the U.S., and it already made up more than 11% of all infections the first week of March. Not only is this new subvariant of Omicron significantly more contagious than the original (via U.S. News & World Report), but a recent Danish study showed that BA.2 may be able to reinfect people with the virus at much higher rates than any previous strain of COVID-19. Because each infection raises the possibility of a severe outcome, including death, it is highly possible that this new subvariant, poised to take over the world, will be even more dangerous than the original Omicron variant — and certainly more fatal compared to the common flu.