How Dangerous is the New Coronavirus Mutation: Here is the Data that Just Came out

A Just-Released Table of Comparison from South Africa

In a paper just published on JAMA titled “Characteristics and Outcomes of Hospitalized Patients in South Africa During the COVID-19 Omicron Wave Compared With Previous Waves,” authors assess hospitalized patients with a positive SARS-CoV-2 test result during the fourth contagion wave compared with previous waves. Their goal was to evaluate the mortality and severity of disease associated with the SARS-CoV-2 variant of concern, Omicron (B.1.1.529).

The data was from Netcare, a private health care group consisting of 49 acute care hospitals (>10 000 beds) across South Africa:

As seen in these two tables, the 4th wave (Including Omicron) impacts the broader (younger and healthier) populations (average age of hospital admission of 36 vs. 53-59 in previous waves) including those vaccinated, but it leads to a lower hospital admission rate of 41.3% vs. 67.8-69.3% during the previous waves of Coronavirus. And among those admitted into the hospital, only 31.6% suffered from acute respiratory conditions vs. 72.6-91.2% in previous waves. In other words, only 13% of symptomatic (treated) people had serious respiratory conditions, as compared to 50-55% in previous waves.

That is some good news because even among those admitted into the hospital during the new wave, only 18.5% were moved into Intensive Care vs. 29.9-42% in previous waves. In addition, patients stayed in the hospital for much shorter periods (average of 3 days) during the 4th wave. Overall, 27 out of 2351 people with symptomatic COVID-19 died, which is 1.1% mortality vs. 13-20% in previous waves. In other words, Omicron seems to be 13-18 times less lethal than major previous Coronavirus variants.

But remember not everyone who is infected with the virus is symptomatic or seeks treatment from a hospital. An estimated 40% to 81% of people infected with Coronavirus show NO symptoms. Among the rest with symptoms, probably half have mild symptoms not seeking hospital treatment. So if only 10-30% of infected people seek treatment, the research paper from South Africa confirms that the overall mortality rate (CFR, or case fatality rate) of the virus variants have dropped from 1.3-6% in previous waves to 0.1-0.33%, which is slightly higher than the mortality rates (of 0.05-0.15%) historically associated with seasonal flu virus strains.

The South African study does not look into the vaccination status of those who died so it is unclear how effective or ineffective the vaccines are in reducing new variants’ mortality rates. Also, the study did not conduct virus genotyping on the patients so it is unknown how many of new patients were infected with new variants. They do estimate that generally speaking, the Omicron variant was 81% of the variants isolated by November and 95% isolated by December 2021.

Although the study has several other limitations (outlined by the authors in the paper too), it clearly demonstrates a significant diminishment in the mortality of SARS-CoV-2 mutations, and shift in their pathogenesis towards milder disease.