The coronavirus (COVID-19) is going viral. Many details about the virus are currently speculative. However, there are some facts and possible conclusions that I will further describe here.
Confirmed cases of COVID-19
From its origin in the city of Wuhan in China it has already spread to at least 157 countries worldwide. Looking at the numbers and the countries affected it is becoming clear that COVID-19 is very successful in infecting people and it is spreading fast. As it stands today, on 18th of March 2020, from the 207.518 cases confirmed worldwide, 8248 people have already died. This is already a high number of reported cases already and unfortunately death rates seem to be quite high, too. It is beyond doubt that this is not the end of the coronavirus story at all.
As there is no current cure for a COVID-19 infection, the current measures are intended to slow down the growth of infections in order to prevent overcrowding of hospitals and to permit the treatment of severe cases of people infected with COVID-19, but will not prevent all of us becoming infected by COVID-19 at some point.
COVID-19 Symptoms and course of disease
The course of the disease is varying a lot from person to person. COVID-19 infections can be mild, moderate or severe. Also, non-symptomatic cases are possible. Especially children are often asymptomatic and the course of disease in children is usually mild. An infection initially manifests with unspecific symptoms that resemble flu. These include:
- Fever (90-98 %)
- Dry cough (approx. 70% of reading)
- Tiredness – Fatigue (approx. 40%)
- Slime production – Sputum (approx. 30%)
- Sore throat (approx. 15%)
- Muscle and joint pain (approx. 15%)
- Headache (approx. 15%)
- Chills (approx. 10%)
A running nose is much less common (<10%), Same accounts for gastrointestinal complaints (nausea, diarrhoea1, vomiting) or conjunctivitis (eye infection).
Progression towards serious course of disease
However, COVID-19 infections can worsen and progress to a viral pneumonia (lung infection)1, causing additional symptoms, like shortness of breath (Dyspnoea) quicker breathing frequency (Tachypnoea), and chest pain. From hospitalised cases, 17 to 29% of patients develop acute lung failure (ARDS).
People at risk
This accounts especially for people with previous illnesses like cardiovascular disease, diabetes, respiratory diseases, liver and kidney diseases, and cancer. Generally old people above 60 years and immunosuppressed patients are at a much greater risk of serious disease and disease progression towards pneumonia. The latter groups also may have additional atypical symptoms and may lack fever despite advanced disease.
Many people don´t show any symptoms
Most probably, the majority of people infected with COVID-19 don´t show any (or only very mild) symptoms, which means they are asymptomatic. Asymptomatic infections might account for up to 80% of all infections, as some sources suggest. It is being assumed that asymptomatic people might be able to transmit the virus to other people2, thereby largely contributing to the viral spread. Actually, one study finds that asymptomatic people might account for the infection 79% of confirmed cases2.
One huge bias for an exact picture of the real infection numbers and the spread of disease in different countries worldwide are the diagnostic tools. The standard testing method currently recommended by the WHO is reverse transcription polymerase chain reaction (rRT-PCR). Samples are taken from a nasopharyngeal swab or sputum sample. The problem is, testing is (not yet) done on a large scale.
Many people are not being tested
Every European country has different COVID-19 testing criteria. The problem is, current testing policies and capacity in different European countries are preventing even symptomatic people to be tested. Even in Germany – the country that is probably testing the most in Europe, because the calculated death rates seem to be the lowest – only a small percentage of people with symptoms are actually tested for COVID-19. Furthermore, asymptomatic people are very rarely tested and will therefore not appear in the official statistics.
In Germany, only people that had prior contact with a confirmed COVID-19 case, people who have been in China or Italy, or people with clinical or radiographic signs of a viral pneumonia are eligible for COVID-19 testing by the national healthcare bodies. This testing policy seems to be changing in the past days, allowing also people with moderate symptoms to be tested. However, there are several reports of people with clear COVID-19 symptoms that had to go to several places to finally get tested. It´s also clear that many people with only mild symptoms are not willing to make such an effort. Furthermore, Germany can currently process only about 10.000 tests a day (Information from 11th of march).
The real infection numbers
It is very likely that there are far more people already infected by COVID-19 than the current numbers suggest, because only the people that had a positive COVID-19 lab test are currently mentioned in the statistic. The real infection numbers are the sum of confirmed cases by COVID-19 lab testing and the current dark figure, which is the number of infected people that are not confirmed by any lab test (undocumented infections).
How much the real infection numbers differ from the current data of confirmed COVID-19 cases, only depends on the amount undocumented infections, which can only be estimated.
Real infection numbers – An estimation
In Europe, there are far less people tested than necessary to get a clear estimate of the real infection numbers. Unfortunately, the limited testing capacity is making it literally impossible to test even only the people with typical COVID-19 symptoms, not talking about mild or asymptomatic cases. Another issue with the current testing in Europe is that the negative test results are not published. However, also the negative test results are needed to get a good estimation of the real infection numbers.
Recent scientific publications estimate, that undocumented infections might account for 86 %2to 96 %3. If 86 % of all people infected are actually asymptomatic (and thus are currently not being tested)2, the real infection numbers would be 5-6 times higher. If it 96 %3 were asymptomatic, as a recent publication suggests3, the real infection numbers would be even 20 times higher. I personally estimate that the real infection numbers are 100 times – if not even 1000 times – higher than the number of confirmed cases suggest.
Without taking the testing policies and capacity into consideration it is very clear that asymptomatic are currently not being tested for COVID-19. If 80% of all people infected are actually asymptomatic, as some sources suggest, the real infection numbers would be 5 times higher than the number of confirmed cases.
Not too many people are actually tested
If you also take into account that testing policies are modest and testing capacity is low throughout Europe, the real infection numbers must be much more than only 5 times the number of confirmed cases.
If you consider that every 4th infected person that is showing symptoms is actually tested positive, the real infection numbers would be 4×5= 20 times the number of confirmed cases.
If you consider that every 10th infected person that is showing symptoms is actually tested positive, the real infection numbers would be 10×5= 50 times the number of confirmed cases.
If you consider that every 20th infected person that is showing symptoms is actually tested positive, the real infection numbers would be 20×5= 100 times the number of confirmed cases.
As you can see, the real infection numbers could easily be 100 times, if not 1000 times higher than the number of confirmed cases suggest.
Number of deaths and death rates
Unfortunately, the number of deaths that are attributed to COVID-19 infections seems to be quite high. As it stands today, on 18th of March 2020, 8248 people have already died after a COVID-19 infection worldwide. The current number of 207.518 confirmed COVID-19 cases and 8248 deaths, results in a calculated death rate of 4 % worldwide.
In Italy, the most affected European country, the current death rate seems to be higher, at somewhat 8 % and in Spain it´s 4,5 % of confirmed cases that died from COVID-19. The lowest calculated death rate in Europe is in Germany with only 0,2 %.
Why do the death rates differ so much?
The fact that death rates in Europe differ so much is another hint that the numbers of confirmed cases do not represent the real infection numbers at all. Looking at the death rates in Italy (8 %) and in Germany (0,2 %), this suggest that the numbers of confirmed cases are actually totally misleading.
If in Italy less people that are infected with COVID-19 are tested than in Germany, the numbers of confirmed cases are lower and the death rates SEEM higher. This is exactly how it looks like today. Most probably the real infection numbers in Italy are 8 % /0,2 % = 20 times higher than in Germany.
Death rates are possibly much lower than currently expected
Considering that the real infection numbers are presumably much higher, death rates are likely to be much lower than it looks at first glance. If there were 10 times more real infections, than the number of confirmed COVID-19 cases suggests, death rates would be 10 times lower, meaning 0,4 % worldwide, 0,8 % in Italy, 0,45 % in Spain, and only 0,02% in Germany. Also, according to the real infection numbers, serious course of disease from COVID-19 would also be 10 times less frequent.
These death rates are actually very similar to the seasonal flu, which would actually be good news. However, as there will become more and more people infected, the total number of deaths from COVID-19 will most probably exceed the number of deaths from seasonal flu.
You should also take into account that death rates might turn out to be even 100 times lower than it currently seems, simply because of the fact that it is likely that the real infection numbers are 100 times higher than the number of confirmed COVID-19 cases.
Measures on an individual level
Of course, it makes sense to protect yourself from a possible COVID-19 infection. The only officially agreed measure to prevent infections with COVID-19 is to avoid contact with body fluids and especially protect your eyes, your nose and your mouth. Therefore, not shaking hands, not kissing, and washing your hands regularly, especially when you enter your house or after contact with other people, is a prerequisite.
Also, avoiding gatherings of crowd is another important measure to reduce your personal risk of infection with COVID-19. That´s why football games in many European countries as well as the Champions and Europa league will be held without fans, at least until Easter, if not longer. The Euro Cup was even postponed to next year.
Also, more and more European countries are implementing curfews, so that many people are not allowed to leave the house for other than really necessary reasons. These measures are important to prevent an exponential growth of infection numbers, that could result in too many hospitalised people and overcrowding of hospitals. This is often referred to flattening the curve (see an excellent article and graphic here). These measures will slow down the infections in the population, they will, however, not protect you from becoming infected on the long term.
Last but not least, you should make sure you are getting enough vitamins, minerals, and secondary plant substances, as it is well known that these micronutrients can increase the strength of your immune system and thus prevent bacterial and viral infections. Whether this is also true for COVID-19 is currently unknown, but likely.
What does this all mean?
Most probably, many more people (10 to 100 times more) are actually already infected with COVID-19. That also means that a serious course of disease and death rates will most probably turn out to be actually much lower (10 to 100 times less) than the current data suggests. That means if you consider the real infection numbers, the real death rates are possibly actually very similar to the seasonal flu, or even lower.
It might sound strange to you, but this is actually good news. For me it shows that not all corona-news are a reason to panic. Keep in mind that the current measures are intended to slow down the growth of infections in order to prevent overcrowding of hospitals and to permit the treatment of severe cases of people infected with COVID-19, but will not prevent all of us becoming infected by COVID-19 at some point. It also gives us more time to find a drug that works against the infection. A vaccine is not expected before 2021.
As at least 80 % of people do not show any symptoms you are most probably on the safe side. If, however, you are belonging to a risk group the above stated individual measures are really important for you to decrease your personal risk of an infection with COVID-19. This accounts especially for people with previous illnesses, immunosuppressed patients and generally old people above 60 years.
In a nutshell: Keep calm and wash your hands
1 Huang, C. et al. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. Lancet 395, 497-506, doi:10.1016/S0140-6736(20)30183-5 (2020).
2 Li, R. et al. Substantial undocumented infection facilitates the rapid dissemination of novel coronavirus (SARS-CoV2). Science, doi:10.1126/science.abb3221 (2020).
3 J., S. & Galanti, M. Direct Measurement of Rates of Asymptomatic Infection and Clinical Care-Seeking for Seasonal Coronavirus. medrxiv. (2020).