Note: these updates are translated by means of Google Translate.
Covid-19: China relativized: But predominantly mild illness
By Prof. Dr. med. Pietro Vernazza, 18 February 2020
The Chinese CDC published a fairly comprehensive analysis of the new corona outbreak yesterday Monday for the first time. In total, data on over 70,000 patients were collected. This analysis puts a lot of earlier fears into perspective. Our study confirms our assumption that the new coronavirus outbreak (Covid-19) is a disease that is more comparable to severe seasonal flu. Of course, it is still worth waiting for the further course, but overall the further experiences with the diseases outside of China seem to point in the same direction.
- Over 72,000 sick people recorded in the study, detailed data from 44,672 confirmed cases in China
- Over 80% of sufferers have mild symptoms
- 14% of those with a severe clinical picture, 4.7% with critical illness
- In the first affected province of Hubei, the death rate was around 2.9%, in the other regions of China only 0.4%
- Deaths were observed only in older people over the age of 40 (including 0.2%)
- No deaths in children under the age of 10
- Death rate increases with age:
- 0.4% for 40+ year olds
- 1.3% for 50+ years old
- 3.6% for 60+ year olds
- 8% at 70+
- The death rate is higher in men than in women (2.8 vs. 1.7%) and
- Higher in patients with heart or diabetes and hypertension
(the latter observation suggests that therapies with ACE inhibitors could be a risk factor)
- Medical personnel have a high risk of infection (3019 sick, five deaths [0.16%] until 13.2.20)
- In the first affected province of Hubei, the death rate was around 2.9%, in the other regions of China only 0.4% (can also increase!)
- The course of the epidemic has decreased since the peak on January 25th (until February 11th)
Many pieces of the puzzle come together
This observation actually coincides with other observations from the past few days in cases outside of China. It showed up:
- People with mild illnesses are particularly common (outbreak Germany)
- The infection rate is particularly high, especially where people are close together (cruise ship)
- After undergoing infection, you are likely to be immune
- Severe cases are found predominantly in older people and with pre-existing illnesses
- Our hypothesis that treatment with ACE inhibitors could have a negative effect on the clinical picture is based on:
- The corona virus (COVID-19) uses the ACE receptor to enter the human cell
- In patients receiving blood pressure therapy with ACE inhibitors, the number of ACE receptors on the cell is increased (upregulated).
- Patients at high risk of death (heart, diabetes, blood pressure) are often treated with ACE inhibitors
The publication of the Chinese CDC must still be critically examined. Even if the new Coronvavirus (Covid-19) were like severe seasonal flu in the long term, we must not trivialize the epidemic. At the moment, it is still appropriate internationally to stop the further spread by means of containment measures. Because unchecked, the infection will infect many people in a very short time. Even mild illnesses can lead to failures in everyday life in large numbers. But the data at least suggest that panic is out of place.
It is still important that in addition to containment, we also try globally to promote effective, simple measures. Mathematical models were able to show that simple hygiene measures are sufficient to massively dampen the spread. We therefore recommend systematic compliance with general hygiene behavior, as the Federal Office of Public Health describes very clearly on its homepage under ” Hygiene in the event of a pandemic “ ( link on video ).
We were repeatedly asked about the differences between the lethality of HCoV-19 and seasonal flu. We do not want to trivialize the lethality of the new coronavirus infection. It is quite possible that this is even a factor of 10 above that of a severe flu season. However, we would like to point out that the annual, recurring seasonal flu is a serious illness that also kills young people every year, and that, unlike the current coronavirus infection, we punish it year after year. If in Eastern Switzerland barely 10% of nursing staff are vaccinated against flu, then this is an indication that we are neglecting the extent of this seasonal illness.
What is special about the new coronavirus infection is that this wave of illness suddenly strikes a non-immune population and is therefore a major burden on the health system in the short term . In contrast to seasonal flu, as a population we build up immunity to the new corona viruses. This is in contrast to the flu, against which we are only partially immune. PV3
Maybe 90% of corona infections go unnoticed!
By Prof. Dr. med. Pietro Vernazza, 20 March 2020
At the moment we are maximally busy with our activities to prepare for the upcoming spread of COVID in Switzerland. The political decisions of the past few weeks have been rash in part. That was also necessary, because in such situations we cannot miss time. But it is also worthwhile from time to time to reflect on what we are doing – and often we do it simply because the others have shown it to be -.
Follow the science!
With this quote, Barack Obama sent a clear signal in his presidential term: he made it clear that political decisions must ultimately always be based on evidence. And he has always consulted his best scientists. An attitude that is currently neglected in the United States. But not only in the United States. We too are in a state in which the inclusion of technical expertise in the political decisions around Corona hardly has any space. Day-to-day business almost no longer allows reflection.
Pioneering work barely noticed by the media
So it comes as no surprise that the publication by Li et al. passed us almost unnoticed. But the work published in the highly endowed “Science” has it all. The epidemiologists investigated the spread of COVID-19 in China and investigated how often the new infections were discovered. The methodology is sophisticated, it is based on calculations of contact probabilities and also includes mobility data and other complex information.
However, the result is told quite simply:
- Around 85% (82-90%) of all infections occurred without anyone noticing the infection *
- About 55% of the undetected infected infected other people
We have actually suspected this for a long time. Otherwise it would not have been possible to explain that the number of infections in China dropped to zero after a few weeks. This cannot be explained with an immunity rate of less than 1% of the population (less than 100,000 people in Wuhan are affected by around 10 million people). It would not even be surprising if further studies put the rate of silent infections even higher.
Consequences for epidemiology, case management and politics
This new and not surprising finding must quickly lead to an evidence-based correction of our measures.
- Stops wild test activity. Subito!
First of all, it is clear that we have to stop doing COVID-19 tests. These tests are of no use to anyone because they only discover the smallest part of the contagious. The costs are prohibitively high at CHF 200 per test. It is inefficient. Tests help us treat patients with serious infections in the hospital. There we want to know who is infected. But to stop the spread, the work of Li et al. shown, it brings nothing. I would like to praise the BAG, which has long said that you should no longer test all suspects. But the message has not yet arrived ** .
- Finally inform the population and speak plain text!
This infection is mild for young people. Fear is not a good guide. Most people face a terrible, dangerous illness. Yes, it is true. About one in ten people diagnosed die in Italy. But as we now know from this science work, this should be one of 1,000 infected people. And what we also know from Italy and China: Around 50% of the deceased patients are over 80 years old, almost 90% are over 70 years old. This does not mean that there are not tragic individual fates behind these numbers. But often – as we know from the flu season – it affects people who are at the end of their lives. At a point where they may even prepare themselves for death or, based on their condition, always expect it to happen. Life is finite. We also have to remind people of that.
- Think about the next steps!
I have already mentioned that immediate measures must be immediate. That is in their nature. But then it takes phases of prudence and reflection. We have to think deeply about the next steps. But based on the new insight, we also have to understand that many of the measures that we have implemented so massively today may even be counterproductive. Not that I already say that I know the solution. But at least we have to ask whether our approach is correct.
For example: We are convinced that closing schools was an important step. Correct, we know this from the experience of the Spanish flu. But I asked the federal government: Nobody had a scientific basis for this decision. It was introduced because the other countries had also introduced it. But if we now assume that perhaps a large proportion of the children will be infected quickly (and that is what the epidemiological figures leave us with), it could at least theoretically be that it would be best if our children became immune as quickly as possible ***. Because we know two things: If many children become immune, the disease will spread much more slowly. Exactly what we want. And what we also know: children do not become seriously ill and never die from the disease. But we also have to consider all other measures to limit the spread. Perhaps it would at least be worth considering whether isolation measures should be restricted primarily to people at risk and whether young, non-vulnerable people could gain access to the economy.
Not that I have now called for the end of the measures. But let’s think about it. Now.
Comment March 23 :
I thank the over 100 enthusiastic letters (which I could not answer all) as well as the 4 critical votes so far, which I take seriously.These included tips that I would like to include in a more precise way:
* unnoticed infection is imprecise and should not be interpreted as “asymptomatic”. They are infections that have not been recognized. Predominantly with very mild symptoms can be assumed. It can also have asymptomatic cases among them.
** Two critics wrote that I would object to the BAG’s stance. The opposite is the case. I am fully on the BAG line and emphasize this: The BAG has a very clear, limited test strategy. I resisted the massive demands of other groups, which (well-meant) require a much broader testing, in the idea that this would inhibit the spread. Currently have no more tests. We need this for the patients who need to be hospitalized. Without diagnosis we are blind.
*** I never said the decision was wrong. On the contrary. I just said that we have to critically examine whether it could possibly have the wrong effect.