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Coronavirus (COVID-19) Mortality Rate

Coronavirus (COVID-19) Mortality Rate


Covid-19 death toll in Italy shoots past 10,000 with no signs of respite

3.4% Mortality Rate estimate by the World Health Organization (WHO) as of March 3
In his opening remarks at the March 3 media briefing on Covid-19, WHO Director-General Dr Tedros Adhanom Ghebreyesus stated:

“Globally, about 3.4% of reported COVID-19 cases have died. By comparison, seasonal flu generally kills far fewer than 1% of those infected.” [13]

Initial estimate was 2%
Initially, the World Health Organization (WHO) had mentioned 2% as a mortality rate estimate in a press conference on Wednesday, January 29 [1][2] and again on February 10. However, on January 29 WHO specified that this was a very early and provisional estimate that might have changed. Surveillance was increasing, within China but also globally, but at the time it was said that:

We don't know how many were infected ("When you look at how many people have died, you need to look at how many people where infected, and right now we don't know that number. So it is early to put a percentage on that."[1][2]).
The only number currently known is how many people have died out of those who have been reported to the WHO.
It is therefore very early to make any conclusive statements about what the overall mortality rate will be for the novel coronavirus, according to the World Health Organization [1][2].
Mortality Rate as of Feb. 20 in China (findings from the Report of the WHO-China Joint Mission)
The Report of the WHO-China Joint Mission published on Feb. 28 by WHO [12] is based on 55,924 laboratory confirmed cases. The report notes that "The Joint Mission acknowledges the known challenges and biases of reporting crude CFR early in an epidemic" (see also our discussion on: How to calculate the mortality rate during an outbreak). Here are its findings on Case Fatality Ratio, or CFR (the mortality rate):

"As of 20 February, 2,114 of the 55,924 laboratory confirmed cases have died (crude fatality ratio [CFR: 3.8%) (note: at least some of whom were identified using a case definition that included pulmonary disease).

The overall CFR varies by location and intensity of transmission (i.e. 5.8% in Wuhan vs. 0.7% in other areas in China).

In China, the overall CFR was higher in the early stages of the outbreak (17.3% for cases with symptom onset from 1-10 January) and has reduced over time to 0.7% for patients with symptom onset after 1 February. " [12]

The Joint Mission noted that the standard of care has evolved over the course of the outbreak.
Mortality Rate, as discussed by the National Health Commission (NHC) of China on Feb. 4
Asked at a press conference on February 4 what the current mortality rate (or case fatality rate, CFR) is, an official with China NHC said that [7]:

The formula they are using is: cumulative current total deaths / current confirmed cases. Therefore, as of 24:00 on Feb. 3, the formula used was 425/20,438.
Based on this figure, the national mortality rate to date was 2.1% of confirmed cases.
There might be mild cases and other cases not reported.
97% of the country's total deaths (414) were in the Hubei Province.
Mortality rate in Wuhan was 4.9%.
Mortality rate in the Hubei Province was 3.1%.
Mortality rate nationwide was 2.1%.
Fatality rate in other provinces was 0.16%.
Deaths in Wuhan were 313, accounting for 74% of China's total.
Most of the cases were still mild cases, therefore there was no need to panic.
Asked why Wuhan was so much higher than the national level, the NHC official replied that it was for lack of resources, citing as an example that there were only 110 critical care beds in the three designated hospitals where most of the cases were sent.
National mortality rate was basically stable, as of Feb. 4 at 2.1%, and it was 2.3% at the beginning of the epidemic, which can be seen as a slight decline.
Front the analysis of death cases, it emerged that the demographic profile was mainly male, accounting for 2/3, females accounting for 1/3, and is mainly elderly, more than 80% are elderly over 60 years old, and more than 75% had underlying diseases present such as cardiovascular and cardiovascular diseases, diabetes and, in some cases, tumor.
Elderly people with basic diseases, as long as they have pneumonia, were clinically a high-risk factor regardless of whether it is a coronavirus or not, and the case fatality rate was also very high, so it is not that the case fatality rate of pneumonia is high because of the infection with the new coronavirus. "This point must be explained to everyone," concluded the NHC official.[7]
Preliminary study providing a tentative 3% estimate for case fatality rate
A preliminary study published on The Lancet on January 24 [3] provided an early estimation of 3% for the overall case fatality rate. Below we show an extract (highlights added for the relevant data and observations):
Of the 41 patients in this cohort, 22 (55%) developed severe dyspnoea and 13 (32%) required admission to an intensive care unit, and six died.

Hence, the case-fatality proportion in this cohort is approximately 14.6%, and the overall case fatality proportion appears to be closer to 3%.

However, both of these estimates should be treated with great caution because not all patients have concluded their illness (ie, recovered or died) and the true number of infections and full disease spectrum are unknown.

Importantly, in emerging viral infection outbreaks the case-fatality ratio is often overestimated in the early stages because case detection is highly biased towards the more severe cases.
As further data on the spectrum of mild or asymptomatic infection becomes available, one case of which was documented by Chan and colleagues, the case-fatality ratio is likely to decrease.

Nevertheless, the 1918 influenza pandemic is estimated to have had a case-fatality ratio of less than 5% but had an enormous impact due to widespread transmission, so there is no room for complacency.

Death rate among patients admitted to hospital
A study on 138 hospitalized patients with 2019-nCoV infection, published on February 7 on JAMA, found that 26% of patients required admission to the intensive care unit (ICU) and 4.3% died, but a number of patients were still hospitalized at the time. [9]

A previous study had found that, out of 41 admitted hospital patients, 13 (32%) patients were admitted to an ICU and six (15%) died.[5]

Days from first symptom to death
The Wang et al. February 7 study published on JAMA found that the median time from first symptom to dyspnea was 5.0 days, to hospital admission was 7.0 days, and to ARDS was 8.0 days.[9]
Previously. the China National Health Commission reported the details of the first 17 deaths up to 24 pm 22 Jan 2020. A study of these cases found that the median days from first symptom to death were 14 (range 6-41) days, and tended to be shorter among people of 70 year old or above (11.5 [range 6-19] days) than those with ages below 70 year old (20 [range 10-41] days.[6]

Median Hospital Stay
The JANA study found that, among those discharged alive, the median hospital stay was 10 days.[9]

Comparison with other viruses
For comparison, the case fatality rate with seasonal flu in the United States is less than 0.1% (1 death per every 1,000 cases).

Mortality rate for SARS was 10%, and for MERS 34%.




Virus
Death Rate
Wuhan Novel Coronavirus (2019-nCoV)
2%*
SARS
9.6%
MERS
34%
Swine Flu
0.02%


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