Coronavirus Death Rate Lower Than Thought

While media reports have put the COVID-19 death rate as high as 4.5%, a study at the disease's epicenter in Wuhan found it's actually much lower. The fatality rate of people who develop symptoms of COVID-19 is about 1.4%, and even lower among certain age groups

Fewer people may die from coronavirus than was previously thought, according to new research from a team of infectious disease experts.^[i] The death rate from novel coronavirus, COVID-19, in Wuhan, China, where the virus is said to have originated, is about 1.4% -- far lower than the 3.4% death rate reported by the World Health Organization in early March 2020.^[ii]

While fatality risk is often calculated on the proportion of deaths out of the total number of reported cases, the study took into account estimations of unreported cases, which were thought to be significant in number. "Specifically, delineating the proportion of infections that are clinically unobserved under different circumstances is critical … ," the researchers noted.^[iii]

Using a range of publically available and recently published data sources, the study built a picture of the full number of COVID-19 cases and deaths by age group, including some early cases that may have initially been missed.

Coronavirus Death Rate 1.4% After Developing Symptoms

While the media has reported a COVID-19 death rate as high as 4.5%,^[iv] the study, published in Nature Medicine, found the fatality rate of people who develop symptoms of COVID-19 is about 1.4%.

This varied according to age, with those above 59 years being 5.1 times more likely to die after developing symptoms compared to those aged 30 to 59, while those under 30 were even less likely to die than 30- to 59-year-olds. The researchers noted:

" … [W]e estimate that the overall symptomatic case fatality risk (the probability of dying after developing symptoms) of COVID-19 in Wuhan was 1.4% (0.9-2.1%), which is substantially lower than both the corresponding crude or naïve confirmed case fatality risk."[v]

The risk of developing symptoms increased with age at a rate of approximately 4% per year among those aged 30 to 60 years. When broken down by age group, the fatality rates were as follows:^[vi]

• 15 to 44 years: 0.5% (with a potential range of 0.1% to 1.3%)
• 45 to 64 years: 0.5% (with a potential range of 0.2% to 1.1%)
• Over 64 years: 2.7% (with a potential range of 1.5% to 4.7%)

Among younger people, "The chance of serious illness from coronavirus infection … was so low, the scientists estimate a fatality rate of zero," Stat News reported.^[vii] These fatality rates may be even lower in areas outside of Wuhan, the researchers noted, in part because their health systems were not as overwhelmed.

In fact, as of February 29, 2020, they found that the crude case fatality risk outside of Hubei province (Wuhan is the capital of Hubei) "was 0.85%, which is ~23-41% lower than our sCFR [symptomatic case fatality risk] estimates of 1.2-1.4% for Wuhan."^[viii]

Another unknown factor is the number of asymptomatic or very mild cases. If these cases were included, the overall infection fatality risk would be even lower than the 1.4% for symptomatic cases, echoing other reports that COVID-19 death rates may have been overestimated.