Why COVID-19 has to be taken seriously

BY GEERT MOLENBERGHS (KU Leuven and UHasselt), PIERRE VAN DAMME (UAntwerpen), SARAH VERCRUYSSE (UHasselt) and NIEL HENS (UHasselt and UAntwerpen). Are they really necessary, all those far-reaching measures to limit the number of SARS-CoV-2 infections? Without a doubt, according to researchers from KU Leuven, UHasselt and UAntwerp. In this blog they explain why we’d better take COVID-19 seriously.

Written by professor Geert Molenberghs(KU Leuven and U Hasselt), professor Pierre Van Damme (UAntwerpen), professor Sarah Vercruysse (UHasselt) and professor Niels Hens (UHasselt and UAntwerpen).

It has often been claimed that the infection with SARS-CoV-2, causing COVID-19, is overrated and has led to global hysteria. A large variety of arguments have been used to underscore this position. For example, in Belgium up to now only 40 people have died from COVID-19, under the age of 45. If we add the age segment from 45 to 65 years of age, we have an additional 500 deaths. So, for people under 65, the mortality has not even increased when compared to what is typically seen. A suggestion often heard is to separate the younger from the older generation, with a cutoff at age 65, to then protect the older generation, and let the younger generation go on with their life and keep the economy going.

Indeed, that is what we often hear…

Symptoms and fatality

It is true that many people who get infected live through it without symptoms, or with mild symtoms at best. Unfortunately, roughly a fifth of the patients develop serious symptoms and are admitted to hospital. A good fraction is admitted to intensive care and, depending on the country, between 0.5% and 1.5% or more of the patients do not make it.

For Belgium, the first wave (March – June 2020) led to roughly 10,000 deaths. The vast majority occurred among the elderly population, given the steep infection fatality rate curve. Men of 85+ years had an infection fatality rate of 13%, for females this was 11%. So, one in eight 85+ males who got infected died, with one in nine females who got infected passed away.

It is true that children are relatively unaffected: their infection rate is low, and there is mortality remains an exception. Post-puberty youngsters tend to get infected much more easily, and really many live through it well. However, also in this group a sizeable fraction gets critically ill, with sometimes weeks in intensive care, in coma, with ventilation, and long rehabilitation afterwards.

We are seeing better and better that also people with mild to moderate infections still show quite severe damage: to the lungs, but also to the heart. Cardiovascular problems are coming to surface now: scar tissue in the heart, leading to arrhythmias, that apart from being uncomfortable, will lead to increased risk of heart attacks. These conditions are seen in young people with mild infections.

So, when people say: “Let us contract COVID-19, get over it, and then get on with our life.” It is like playing Russian roulette: there is a small risk of dying, but a considerable risk of coming off with heart and/or lung damage.

In addition, there is more and more evidence of brain damage. These effects get worse and worse with increasing age.


The incubation time is relatively long, roughly a week. One of the many tricky things with this infection is that people are infectious, and often very infectious, 4 days before they develop symptoms. Another one is the occurrence of superspreaders and superspreading events. We did not even know that so very well in February-March 2020, but it has become clearer and clearer. It has been suggested that the prevalence of superspreaders might be increasing, but this requires careful study.


Another key aspect that unfortunately we do not understand at this time is how the immunity works. Antibodies take a while before being detectable, then the antibodies wane again. So, immunity might work in a different way, e.g., via T cells. How long does protection last? Will it be complete or partial protection? We just do not know yet. It is too early for that.

A new normal

To lead a carefully redesigned normal life, we need to work on several levels:

  • People should observe the key social distancing and hygienic rules.
  • Social contact should be done with care.
  • Governments need to have contact tracing and cluster follow up in place.
  • We need antiviral medication. The more there are, and the better they work, the more will we be able to mitigate symptoms, to avoid people from developing very serious form of the illness.
  • Evidently, we need a vaccine, and this may take some time. While the speed of vaccine development is unprecedented, the careful assessment of a vaccine’s safety and efficacy takes some time. In the long run, the virus may become milder and milder; but we should not count on that happening too quickly. Our hope rests on the vaccine.

Deadly April

The month of April 2020 in Belgium was the most deadly month of April since World War II. There were a few months of January and February in the 1950s and 1960s that were about equally deadly, because of flu pandemics. However, there were no social distance measures put in place. Should we have had no measures like that, there is a huge risk that we would have had between 50,000 and a quarter million deaths – rivaling the Spanish Flu. This is because an unmitigated epidemic would likely lead to a completely overwhelmed health care system. We have been seeing that around the world, including mass graves in cities like New York City.

Crush the curve

A second wave of the epidemic is potentially more dangerous because it tends to set off against the background of a good amount of virus circulating. This is why we need to make sure that we flatten the curve and make it go down until we reach a very low level of viral circulation. New Zealand and Finland have been doing that, and can lead a reasonably normal life.

We should all take COVID-19 seriously. Those who do, adhere to the measures and protect themselves and their loved ones, while we wait for a vaccine. Till then, we can and should build further on the strength of our behaviour and in the continuously increasing scientific insights to fight the epidemic.

This article originally stated that one in six men older than 85 died from COVID-19, this has been corrected to ‘one in eight’ (13%).


  1. Interesting article. You say that ‘a sizeable fraction gets critically ill’, what fraction is this? And also, what is the fraction of people with mild or moderate symptoms that develop serious damage?

  2. In summary, we make the enitre population suffer from less freedom, and make the entire economy a complete mess here in Belgium for many generations to come, because “we don’t know many things about this virus” and thus we better “play the extreme safe cards”. Example: the patients of Covid-19 may have lungsdamage. But we don’t know if that means they will die sooner than without this lungsdamage. In comparison to this: Are we banning all cars from the streets and all planes from the air because they damage our lungs…no, so why for Covid-19 ‘unproven risks’ we are so drastic? Did the professors also analyse another “unknow”, like for instance: how many people will die from forced isolation from normal socializing, how many people will die from loosing their jobs, how many people will die from being unable to pay back their real estate loans, how bad is the impact on our kids who see the prospect of making friends for life when joining the university this year taken a way (a digitial teaching process is by far not equivalent to the real experience, how can you ever make friends for life, a network for life?). We are killing ourselves in another way as a response to not get killed by Covid-19, this is really crazy to see happening

  3. Just one remark: An infection fatality rate of 13%, means that one in seven to eight 85+ males who got infected died.

Reacties zijn gesloten.