Cytokine Storm In Severe COVID-19 Infections

In rare cases, COVID-19 causes a cytokine storm. Today we explain what it is, even if it only happens in exceptional cases.

During the Corona crisis we learned a lot about infectious diseases and we also have to familiarize ourselves with new terminology. Today we explain what a cytokine storm is that can occur in severe cases. Read on to learn more about it.

Some data about COVID-19

In March, the death rate from COVID-19 was estimated at 3.7 percent of those infected. According to recent calculations, 49.21 people per 100,000 inhabitants (healthy and infected) have died in Spain.

The risk of dying from this disease, however, depends very much on age. Up to the age of 40, the mortality rate is less than 0.2 percent, but in people over 80 it increases to 15 percent.

It is important to keep this data in mind because  only a very small percentage of infected patients experience a cytokine storm. So you shouldn’t worry about it. Nevertheless, we would like to inform you about what exactly a cytokine storm is.

Cytokine storm: when our immune system damages us

Diseases such as COVID-19 or influenza can lead to hyperactivation of the immune system if the disease progresses seriously. This process is also known as a cytokine storm. 

As a result of an immune reaction of the organism, certain cells release cytokines in order to send further immune cells to the area of ​​inflammation and to intensify the reaction. The cytokines allow cells such as T lymphocytes or macrophages to migrate to the site of the inflammation. 

This process is retroactive, because the release of cytokines also promotes the further production of these small proteins by the immune cells.

This protection system is so efficient that it can be too strong and have harmful effects. For example, when the SARS-CoV-2 virus enters the lungs, the cytokines direct the antibodies into this area of ​​the body, where they fight the pathogens by causing local inflammation.

An uncontrolled release of cytokines or excessive retroactivation  can trigger hyperinflammation of the lung tissue. This can cause serious harm to the patient or be fatal.

Zytonkin storms are common in the elderly, and  not just related to COVID-19. They can also result from other viral infections such as flu, SARS, MERS and diseases such as multiple sclerosis or pancreatitis.

What to do in a cyctokine storm

Medical explanation of this phenomenon requires terminology that can be confusing. In order to answer this question in a simple and understandable way, we can briefly summarize that in these cases it is necessary to reduce the efficiency of the immune system. 

Steroids are hormones that are used  in these processes. Because we know that they reduce the intensity of the immune response in the short term. However, their effectiveness in patients with COVID-19 has not yet been adequately studied.

It is particularly difficult to find a balance  so that the immune system is strong enough to fight the pathogen but does not endanger the patient’s life.

There is good news on the subject. A Chinese study used an antibody that inhibits the immune response to some extent. This is used, for example, in patients with arthritis or cancer when they are suffering from a cytokine storm.

In this study, 21 patients with serious COVID-19 disease were given the antibody tocilizumab – Actemra. In a few days, the doctors were able to significantly reduce the fever and other symptoms. Of these 21 treated patients, 19 survived and were discharged from the hospital after two weeks.

This and similar antibodies are also being investigated in other countries, such as Italy. But the test groups are so far too small to get reliable results. 

Summary: is a cytokine storm worrying?

Today we looked at one of the worst situations: In a cytokine storm, your own immune system reacts so strongly that it is counterproductive and works against the patient. However, this does not mean that an infection with SARS-CoV-2 has to be fatal, because a cytokine storm only occurs in exceptional cases. 

Nevertheless, it is important to comply with security measures such as social distancing and to act responsibly. Because we know that COVID-19 can lead to complications that can be serious, especially for the risk groups.