The mortality rate for COVID-19 is being measured by WHO and world-wide as: cumulative current total deaths / current confirmed cases. Isn't this incorrect? Or at least misleading?
The current number of infected patients that are sick shouldn't be incorporated in the equation! Since the final state of an infected patient is either death or cured, shouldn't the mortality rate be calculated by: total deaths / (total deaths + total cured)?
The first formula gives a value of 4.8%, while the latter formula gives an alarming value of 18.8%, for the current statistics of COVID-19!
Both numbers are informative; true mortality rate can only be determined after the pandemics is over. The first number, 4.8%, is currently an underestimate (the outcome of some active cases will be death), the second number, 18.8%, is an overestimate (the outcome of most active cases will be recovery; and it usually takes more time to recover from the disease than to succumb to it). The true mortality rate will be closer to the first number, and maybe even lower than that: 2-3% is not unrealistic.
The current estimates of numbers of COVID-19 cases and deaths are very inaccurate. The sensitivity and specificity of the diagnostic tests for COVID-19 are not yet known in vivo. There are reports of very high sensitivity and specificity in vitro. However a number of confounding factors (e.g. the stage of illness and the way the swab was taken) mean that the false negative rate of these tests may be high in clinical practice.
The numbers of cases reported will also depend on strategies used for screening. Many countries are only screening symptomatic patients presenting to healthcare facilities. Others are attempting to screen a significant proportion of the population.
I believe the total number of cases of COVID-19 is significantly higher than that being reported. There are many confounding factors (both political and diagnostic) that make the initial number of deaths reported as being due to COVID-19 extremely difficult to interpret.
Dmitry Nikolaenko can you please stop spamming questions with your preprint, especially when it does not address the question in hand.
If you want to get people involved in your work open your own discussion on Researchgate please.
The currently reported mortality rates may be overestimates or underestimates, depending on the country and situation. Some countries are testing far more people with mild symptoms or currently asymptomatic, while others are only testing the sickest people (and in some cases, even the sickest people can't get tests). Some countries (like Germany today) are far earlier in their outbreak than others, so most infected people are in their first week or so of illness and will probably get worse.
South Korea was reporting a case fatality rate of 0.6% back in mid-March, but now it's up to 1.9%. More of the people who were infected weeks ago have now died, and some are still sick.
The death to outcome ratio in China, where the epidemics is over, is 1/25. The current worldwide ratio of serious-or-critical to active cases is also 1/25. At this point, it seems that the real death rate, when the pandemics ends, will be closer to 4% than to the current 21%.
The ratio of positive tests to all tests differs among countries (see the comment by Ilana Goldowitz Jimenez above) by about a factor of 52: 1/130 in the United Arab Emirates vs. 2/5 in Brazil.
Some countries, besides China, may have already peaked as hinted by recoveries > active cases: Australia, Austria, Brazil, Germany, Iran, Malaysia, South Korea, Switzerland, Thailand; many other countries are approaching the tipping point.
But the late-comers to the 'party,' USA, Turkey, Russia, and India, will have to wait for their peaks a few more weeks.
https://www.worldometers.info/coronavirus/
The current level of mortality rate shows some impressive differences among Europe Asia and N.America >>> https://www.researchgate.net/figure/ResGa-FxFac-post_fig71_339781431
.... these differences are according to March hypothesis of a COVID19 sensu Hubei-Wuhan and a COVID19 sensu Europe because there are 3 strain (A B C) of SARS CoV / 2 >>> https://www.researchgate.net/figure/ResGa-FxFac-post_fig74_339781431
The dramatic situation of mortality in Central Europe and in particular in Lombardia (N. Italy) is followed in this personal open question for a know-how aid >>> https://www.researchgate.net/post/The_novel_Coronavirus_in_N_Italy_Lombardia_COVID19_2019nCoV_SARSCoV2_shows_a_fatality_rate_compatible_with_SARS-MERS_Why
Based on Antibody testing in New York, USA, the actual mortality is 10 times less than based on COVID-19 cases based on RT-PCR test results
https://www.ny1.com/nyc/all-boroughs/news/2020/04/23/governor-cuomo-daily-coronavirus-update-with-first-antibody-test-results
Because the COViD-19 is still ongoing final mortality figures would be known once the pandemic comes under control.
Current fatality rates are lowest for Qatar and Singapore and highest for United Kingdom, although it is likely that there is overestimation due to so many undocumented SARS-CoV-2 infection, that can be as high as 80% of current figures.
When it comes to the death rate, we should understand three measures. 1. Crude Death Rate (CDR) that measures deaths per total population. 2. Case Fatality Rate (CFR) that measures deaths per total confirmed cases. 3. Infection Fatality Rate (IFR) that measures deaths per total cases.
the later one addresses best for measuring the risk of death for particular diseases. But because it is not possible to know the total cases as every one of the disease is not tested and the real cases are much less than the reported cases in the population the other two measures are used, more recently on the CFR. But CFR has its weakness as stated above.