Why is COVID-19 that dangerous? It's not only because it's deadly

Photo: EPA/Wikipedia/Index

SINCE the beginning of the COVID-19 pandemic, every now and then someone launches theses and new arguments in the media and on social media, that should serve as proof that COVID-19 isn't even a remotely dangerous disease as it is being presented, that it's more or less on the same level as the flu, which suggests that the whole panic about the pandemic is blown out of proportions, and the anti-epidemic measures are excessive because nothing even remotely drastic is undertaken in the flu season.

Moreover, there were doctors and so-called experts who called the scientists who present COVID-19 as a serious threat, panic-mongers and even terrorists.

One of their key arguments in this context is usually the fact that the majority of the infected still don't exhibit symptoms, or only have mild symptoms, which means that the mortality rate of COVID-19 is significantly lower than it seems when the number of deaths is divided with the number of confirmed cases (CFR). Obsessed with only one parameter - the mortality rate of COVID-19 - the deniers of the seriousness of this diseases are always thinking of new calculations of the deaths in the total number of the infected, which is called IFR (infection fatality rate), just to show that the disease is relatively mild, and should not be a reason for disastrous lockdown consequences. As this text will show, that is a wrong and harmful fixation.

Those attempts to soothe the situation cause a dangerous counteract because it encourages people to act as if everything is more or less normal, as it was just the flu season. The attempts to ease the perception of the danger that COVID-19 represents are understandable to an extent. The fear and efforts to stop the spread of this disease have paralysed the economies around the world, causing one of the biggest economic crises in the last hundreds of years and forced humanity to behave in a way that it isn't used to. So it makes sense to ask questions over and over again about which measures are necessary and appropriate, and which are ineffective or excessive. But it doesn't mean that there should be an excuse for a scientific fact to be adjusted to particular political or economic interests.

The features of a disease define public health priorities 

Today we know more about COVID-19 than several months ago, so we are better at assessing how dangerous it is. But one should bear in mind that an infectious disease isn't only dangerous if it's very deadly. Quite on the contrary, as Index already wrote, some pandemics with the biggest number of victims in the world were caused by viruses that weren't as deadly, such as measles, which are one of the most infectious pathogens. In the pre-vaccination era, a couple of million people died every few years during the measles epidemic. On the other hand, the number of Ebola victims, which was much more deadly, is thousands.

How much is an infectious disease dangerous will depend on many factors, including the mortality rate and infectiveness, and the priorities of the health policies are usually defined according to the following key factors:

A) How many people are infected or can be infected 

B) What are the consequences of the disease, which implies the mortality rate, disability, suffering of patients, implications for the family, economic consequences (sick leave, costs of treatment), social consequences (justice, stigmatization), etc.? 

C) How easily can we protect ourselves from the diseases (for example, do we have drugs or a vaccine) 

What do we know today about the facts mentioned above that are crucial for defining health policies, i.e., the healthcare system's response to the new pandemic?

A) How many people are infected or can be infected 

How many people in the world can be infected with COVID-19 will depend on many factors, such as the infectiousness of the virus, which is presented with the basic reproduction number R0.

In one study published in a medical journal, "Immunity," it was estimated that COVID-19 R0 is somewhere between 2 and 6, compared to 1.5-1.8 in cases of the flu. A new study published in a respectable journal "The Cell" showed that in some parts of the world, a new strain of G614 is starting to dominate, which could be between three and nine times more infectious than the one that had been spreading across Europe for the first couple of months. When it would mean that the virus causes respiratory infections and milder symptoms, that would be good news. However, there are no studies so far to confirm it.

On the other hand, if a disease is more infectious, it spreads faster, and it's more difficult to stop it because, to acquire the immunity of the herd, the greater level of the collective immunity of people is required.

Even if we would accept the above mentioned and more conservative estimations for COVID-19 R0, and suppose it's somewhere between 2 and 6, we can calculate that between 50 and 83 percent of people should recover from the virus to develop the collective immunity.

More than 100 million people were infected around the world, but it's still not even remotely close to the number of people infected with the flu per year; the WHO estimated that around a billion people get the flu every year. But one should expect that, despite being more infectious than the flu, COVID-19 still hasn't had time to infect a billion people because it only started half a year ago in China. 

Finally, a new study published in a respectable medical journal, "The Lancet," and conducted in Spain on a sample of 61,000 participants showed that it would be immoral to let the virus circulate freely in the population to get a collective immunity because it would cause a huge death toll. Namely, the serological tests revealed that only 5 percent of the people had antigens in Spain, and at the same time, 28,300 people died. According to that estimation, nearly 340,000 people should die in Spain to gain collective immunity.

The virus spreads in the pre-symptomatic phase of the disease

The feature of the virus to spread without symptoms favors the rapid spread of COVID-19. It makes the spread of the virus easier and makes it harder for the healthcare systems to track and control the disease. SARS was easier to fight off because of its very severe symptoms, which were easy to identify and isolate.

Since no world economy can endure the lockdown for a long time, it's obvious why the gloomy forecast for COVID-19 is realistic, and not merely an unnecessary spread of fear.

B) What are the consequences of the disease

At the very beginning of the pandemic, when it wasn't known how many infected people have only mild symptoms, the mortality rate was expressed by the number of deaths among the infected (CFR). Eventually, as it became clear that much milder infections were going under the radar, great serological studies were made that revealed the possible number of deaths in the total number of the infected (IFR). According to a medical journal "Nature," many studies so far have shown that IFR of COVID-19 is between 0.6% in China, more than 0.7% in France, and up to 1% in Brazil and Spain, which is ten times more than IFR of the seasonal flu, which is usually less than 0,1%. One should bear in mind that IFR is tricky to calculate precisely, especially in the countries that don't have a large number of the infected in the population. 

Finally, the specific mortality rate of COVID-19 in New York is currently around 0.3% - around 23,000 deaths on 8.400.000 citizens, which means that even this percentage is three times higher than the highest IFR of the flu. The specific mortality rate will always be significantly lower than IFR because IFR is calculated only with the infected population, and the mortality rate is calculated with the total mortality rate, which is always multiple times higher.

Whichever way of calculating the mortality rate is taken, there's no doubt that COVID-19 is deadlier than the seasonal flu, at least for now when there's no collective immunity. So far, around 560,000 people died of COVID-19, and approximately 290,000 and 650,000 people die from the flu every year. But COVID-19 numbers are confirmed cases while the flu numbers are estimations.

COVID-19 causes many diseases and damages 

Analysis of the consequences of COVID-19 showed that it causes many different diseases such as pneumonia, acute respiratory syndrome, cardiovascular diseases, diabetes, diseases of the nervous system, organ failures, sepsis, and death. Some of them can leave permanent consequences. There is even a study that shows that young and healthy people with mild symptoms can experience a stroke, and COVID-19 can also cause diabetes.

There is a significant increase in the number of brain damages. Neurologists published in the medical journal "Brain," that heir study on the sample of 40 patients who recovered from COVID-19 and experienced only mild symptoms, showed that ten of them had an inflammation of the central nervous system, ten had brain disease with delirium and psychosis, eighth suffered a stroke, and eight had a bad function of the peripheral nerve, most often diagnosed as Guillain-Barre syndrome, i.e., the immune reaction which attacks the nerves and causes paralysis, and it's fatal in 5% of cases. The experts got worried that the virus could cause subtle brain damages, which could become evident in the following years. 

One significant problem is also the fact that COVID-19 causes a high number of hospitalizations among the infected. It varies from country to country, but one analysis in the USA on the sample of 2,449 patients showed that between 20 and 31 percent of the infected were taken to hospitals, with between 4.9 and 11.5 percent on intensive care. It imposes a great burden on the healthcare system and makes its functioning more difficult, so many people who suffer from other diseases cannot get the necessary diagnostics and treatment. 

One should bear in mind that COVID-19 will cause many psychological problems as well, such as anxiety and stress. As the new measures are introduced, especially the lockdown and the consequences it leaves on everyday activities, routines and income, the growth of loneliness, depression, alcohol, and drug abuse, as well as suicide attempts, are expected. 

C) How easily can we protect ourselves from the diseases 

It's not easy to protect ourselves from COVID-19 because we still haven't developed a vaccine, and there is only a slim chance of a vaccine being developed until the end of the year. At this time, 18 vaccines are being tested on people. Even if a vaccine is developed until the end of the year, there is a question of how long we have to wait to produce a vaccine in a sufficient number and distribute it worldwide. 

Studies have shown that some drugs, such as antiviral remdesivir and corticosteroid dexamethasone, have positive effects on the severity of the disease, but there are no drugs that could prevent the virus so far.

With all that being said, it means that the only solution for fighting off COVID-19 is maintaining physical distance (testing, tracking, and isolating the infected and the people they've been in contact with), wearing masks, maintaining personal hygiene, especially washing hands.

Since the virus is highly contagious, it's challenging to protect the risk groups. As the infection spreads, it's more challenging to isolate the risk groups because it's more difficult to ensure the health of their contacts - family members, caregivers, medical staff, dentists, etc. It means that COVID-19 policies of healthcare systems will have to manage the estimations on how the social and economic segments are important for the society and the economy on the one hand, and what threat they pose to the society on the other hand. 

To conclude, according to everything that we know today, COVID-19 is a dangerous disease, more dangerous than the flu, and every demagogic diminution of its danger is only increasing it - on the one hand, it makes it more difficult to fight the pandemic, and on the other hand, it reduces the importance of responsible behaviour which is unfamiliar and unpleasant.

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