Why is it that the Case Fatality Rate (CFR) may be either overestimating or underestimating the exact or true mortality rate in patients suffering from COVID-19 in the world and different other countries?
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.
The availability of healthcare in general and specifically critical care will affect case fatality. In China and Italy where large numbers of healthcare professionals were infected the capacity to deliver healthcare was substantially reduced.
Another important factor to consider when trying to interpret variation in mortality rates between countries is differences in cultural interpretation of quality of life. This impacts the social and medical ethics and the delivery, limitation and withdrawal of life sustaining therapies.
In many Western cultures quality of life is valued far more than quantity of life. In those setting limitation and even withdrawal of life sustaining therapies are a common mode of death.
In many Eastern cultures quantity of life is valued more than quality of life. In these settings treatment limitations and withdrawals of therapy are rare. Admission to intensive therapy units and prolonged organ support are common. Mode of death is often cardiac arrest.
These differences are magnified when there are limited resources particularly in Western countries. The social and medical acceptance of treatment limitations is increased; this may significantly increase case fatality rates.
The USA has known for two years, what the implications of the virus is going to be, because in 2018, the John Hopkins Center for Health Security ran a simulation called "Parainfluenza Clade X" to determine what the potential would be of a virus pandemic, and they concluded: "...twenty months 150 million people worldwide--two percent of the global population--have died."
"...The global economy has collapsed under the strain, with the Dow Jones average down 90 percent. U.S. GDP down 50 percent, and unemployment at 20 percent. Washington is barely functioning--the president and vice president are both ill, one one-third of Congress is dead or incapacitated."
People involved in that simulation were Tom Daschle (former leader of US Senate), Dr. Julie Gerberding (former head CDC), Jim Talen (former Missouri senator)--Why are all of these people keeping quiet right now, and not telling us what they saw in the global virus pandemic simulation only two years ago, and helping lead us out of this mess, with some new simulations???!!!
This simulation information and attendee list is from pages 201-203 of the Bryan Walsh book, "END, A Brief Guide to the End of the World: Asteroids, Supervolcanoes, Rogue Robots, and more", published in 2019.
Details about the John Hopkins "CLADE X" exercise can be read at
http://www.centerforhealthsecurity.org/our-work/events/2018_clade_x_exercise/index.html
Those death rates were from the 2018 John Hopkins virus pandemic simulation, not any death rates that have been estimated for the real pandemic today. We need new computer models right now, to help us choose the best methods to slow down and stop this real pandemic, but at least we have some clues from the 2018 simulation, what an out of control pandemic could result in?
Saudi Arabia right now has only 1300 cases, and has the slowest doubling rate of every seven days, but in early May should have about 32,000 new cases. Is your country on any kind of Lockdown, or have you gone to strict quarantine yet?
About the virus-curve--California is double its cases every three days, but in order for the curve to bend, the number of days between doubling must be 30 more more, which means we are going to need a total China-style quarantine lockdown. Everyone for their own country, should track the number of days to for the number of cases to double, and when you get 30 or more, that is very good! If fewer than 30 days, need to do more
Since the first reports outlining the deadly nature of the novel Sars-Cov-2 with approx. 15% case fatality rate (CFR), we have come down to a 1,4% CFR in Wuhan and the region the first cases had been reported from.
With the rates still on their way to the peak in Europe we are looking at massive CFRs in Italy and Spain, whereas in Germany is amongst the lowest.
This pattern of decreasing CFRs is typical during the initial phase of a pandemic. The CFR displays an important part in forming strategies both at national and international level from the public health perspective. Estimates of mortality rate and case fatality rate or infection fatality rate are of upmost importance in this process.
However, as it can be demonstrated by the countries mentioned above multiple factors can impact obtaining accurate estimations of the IFR, CFR and overall mortality rate.
In general, the virus under investigation and its clinical impact are new, as we are only three months into the outbreak. Health care resources and financial burden are different in different countries and even regions. Testing quantity and quality is not equally available, in some scenarios testing is simply not possible anymore. In the presence of legislature and resources enabling contact tracing and strict containment measures in suspected individuals, there will be a low real CFR. Finally, the subjects deceased tested positive with COVID-19 are accounting for death by COVID-19 NOT dead with COVID-19. So the underlying diseases are not held responsible for their death but COVID-19 is officially the reason.
Situation in Italy
In Italy we are looking into several key points, resulting in a seemingly high CFR at the moment:
Italy has 3 beds per 1000 inhabitants and 12 ICU beds per 100.000 inhabitants with an overall of about 3000 mechanical ventilators. The median of age of subjects tested positive is 80 years. The region hit hardest is small leading to a healthcare system massively overwhelmed (can't test sufficiently anymore). Lacking of healthcare personnel and specialists in all of Italy.
Taking this into account a massive underdetection of COVID 19 cases is suggestive.
Situation in Germany:
In Germany we are looking into several key points, resulting in a realistic CFR:
Germany has 8 beds per 1000 inhabitants and 30 ICU beds per 100.000 inhabitants with an overal of 22.000 mechanical ventilators. The median age of patients tested postive with COVID-19 is 47 years (350.000 tests per week). Outbreak is still balanced due to strict containment early into the pandemic.
With the simple monitoring of the number of days for the doubling of new cases, can have everyone on the planet become the judges of the effectiveness of their own country's methods. And if the current methods are failing, as they are here in the USA, insist that more stringent methods are employed immediately, to slam the brakes on the virus.
That is the only weakness that the virus has--we watch and monitor and change our behaviors so we do not become prey. The doubling times in China, starting when they had about 1,200 cases on January 24--Two days, then one day, 2 days, 3 days, 5 days, 8 days, then the doubling stopped on February 15, and since then less than a 10% increase, because they were applying the brakes all along, then slammed on the brakes in late February to early March. I am confident we can all do that too, slam on the brakes in only 3 weeks, and stop the doubling of the new cases?
Thanks all for insightful input on the COVID-19 mortality data, that is dynamic as is the spread of SARS-CoV-19.
On closely following the present pandemic, in my humble assessment a combination of the following important factors are responsible for the day-to-day mortality, and fluctuations:
1. Economic capability of the country to test, contain (quarantine contacts and isolate confirmed mild cases at home), and treat seriously sick patients in the hospitals.
2. Hospital beds available in general and ICU beds with functional ventilators available in a country.
3. Number of tests done for SARS-CoV-19 to detect positive cases early vs the mortality (diluting effect on mortality rate) in the country.
4. Comorbidity rate of diseases (Diabetes, Hypertension, pulmonary diseases, obesity, smoking status, heart failure, immune status – congenital or acquired, vaccination status etc) in the country.
5. Viral factor depending on mutation (L or S type) of SARS-CoV-19 in that particular country.
6. Hospital beds, doctors, and nurse to the population ratio of the country.
7. Quality of the healthcare infrastructure of the country.
8. The occupancy rate of the ICU beds by serious cases due to seasonal influenza (responsible for up to 500,000 death yearly) and other locally endemic infections in that country.
9. Temperature and humidity level in that country that possibly may be impacting the transmission of the coronavirus.
10. Demographic factors i.e. population structure (children, young, old, and very old) of the country.
11. Literacy rate (capability to read, understand information, and act on local health policies) of the country.
12. Other factors e.g. malnourishment, quinine/chloroquine/hydroxychloroquine use for endemic malaria, or anti-retroviral medications being used due to high HIV prevalence, may be playing a role in certain countries (e.g. Africa).
13. Very selective testing of symptomatic COVID-19 cases and mortality of critical cases (concentrating effect on mortality), under-reporting (to avoid political effect, or a fear of international monetary support cuts), or over-reporting of mortality (including all SARS-CoV-19 positive cases even if the cause of death was some other comorbid cause; as has been seen in Italy).
13. Last, and most importantly, the BREAKING POINT of sustainability, at which the number of critical case overwhelm the ventilators and other health care in an area, city, or in the whole country. A current example is the situation in Italy, where the doctors are triaging COVID-19 patients for use of ventilators.
Ultimately, one will be able the gauge the definite mortality rate at the end of the COVID-19 pandemic.
Hope the super-scientist Mr. Corona SARS-CoV-19, decides to wind up its business from this hapless world soon.
An interesting conundrum has arisen. There has been a dramatic fall in the number of blood donors in Saudi Arabia a result of social isolation during the Covid-19 Pandemic. Supplies of blood are being depleted.
Patients may die as a result of not being transfused blood severe acute bleeding due to stress ulceration, for example. If the patient has severe or critical Covid-19, the cause of death is actually the Covid-19 but it is likely to be coded as GI tract bleeding.
Lies, damned lies and statistics as Disraeli said. It will be impossible to unpick the true effect of Covid-19 on patient outcomes.
GOOD NEWS from California and the USA on April 2! The days to doubling of total cases is lengthening. In California our total case numbers were doubling like clockwork, every 3-4 days between March 8 and March 29th.
We put on "Lockdown Lite" on the 16th. Then from March 30 to today, the numbers are now doubling every 12 days. Once every country ON THE PLANET goes on a severe-enough lockdown for at least a month, then the total number of cases and days to double, start stretching out after 2 weeks of Lockdown.
There is a good chance of NOT Dying from the virus, if your country institutes the Lockdown immediately, instead of like the USA whose president unfortunately had a chronic infection of "Denier-Disease" whose symptoms are: "a person who refuses to accept the existence, truth, or validity of something despite scientific evidence."
Yesterday, President Trump was still refusing to do any lockdowns in any of the Republican states that support him, which means that a lot of his supporters will be too sick or dead, to be able to vote in November?
A major factor is the length of time it takes to die from this disease. The CFR can appear low in the early days of an outbreak, or any time the number of cases in the region are increasing exponentially. This is simply because most of the infected people are still early in the course of their illness, when the symptoms are usually mildest. People are dying from COVID-19 weeks (even over a month, in some cases) after their first symptoms. We can only know the true CFR in retrospect, after all the patients have either recovered or passed.
There's been a suggestion that elderly people are more likely to die early in the course of their illness, but younger people who die hang on for longer after their first symptoms. It still seems that elderly people are at greater risk, but young people may not be as protected as was originally thought.
Current fatality rates are almost 10-times more than that reported based on
SAR-CoV-2 RT-PCR tests
The CFR is an 10 times overestimating of actual mortality if we extrapolate the initial antibody screening for COVID-19 in New York, USA, due to large number of undocumented (or asymptomatic patients.
https://www.ny1.com/nyc/all-boroughs/news/2020/04/23/governor-cuomo-daily-coronavirus-update-with-first-antibody-test-results
Surely it will depend on the undocumented COVID-19 case by doing SARS-CoV-2 specific antibody testing.
Yaa... number of people died of COVID 19 may be more than what data shown by the company...and it may be due to luck of good testing facilities....
Therefore, because tests for the presence in the human body of the SARS-CoV-2 Coronavirus (causing Covid-19 disease) are carried out in most countries only in people who in a severe, symptomatic condition undergo Covid-19 disease and this is only usually a small part of the community of citizens who are or have been infected with SARS-CoV-2 Coronavirus. In addition, usually 80-90 or more percent. people who died and who were diagnosed with Covid-19 disease also had other co-morbidities significantly lowering the level of the body's natural immunity, respiratory and / or circulatory function, etc.
Best regards,
Dariusz Prokopowicz
Since IFR is more appropiate - Mortality rate( MR ) = Infection fatality rate ( IFR ) + CFR . https://science.thewire.in/health/covid-19-mumbai-comorbid-fatality-criteria-missing-deaths-modelling/