The severity of COVID-19 has been linked to the destruction of the surface of the lungs – both due to the viral attack itself and as a consequence of the immune response described as a “double-edged sword”. The same phenomenon, when patients with healthy immune systems succumbed to the disease was observed during the deadly 1918 Spanish Flu.
Critically-ill COVID-19 patients can be saved by dampening their immune system, a new study from Aarhus University, Denmark has found.
The research indicated that the immune system’s response to fight off COVID-19 by releasing cytokine proteins that impede the spread of viral diseases by slowing down cell division may undermine the lungs of patients leaving them struggling to breathe.
The severity of the disease is linked to the destruction of the surface of the lungs – both due to the virus attack itself and as a consequence of the immune response. The cytokines draw large amounts of fluid and weaken the lung tissue, making it harder to protect against harmful bacteria. Multiple-organ failures associated with so-called “cytokine storms” have been observed in many countries during the COVID-19 epidemic.
“The immune system’s cytokines are a double-edged sword in these types of infections. The cells infected by the virus are prevented from growing and dividing, but unfortunately these cytokines have the same effect on the cells that do not contain viruses, such as those in the damaged lung tissue”, Rune Hartmann, a professor at the Department of Molecular Biology and Genetics at Aarhus University said in a statement.
Therefore, a timely reduction of the immune system’s reaction to the coronavirus could help save lives.
“Our new results show that the damaged lung cells are not repaired. The ideal treatment for people who are seriously ill with respiratory viruses is therefore to initially stimulate cytokines early during infection and then down-regulate them later to avoid killing the patient”, Hartmann explained.
Despite the new study having been conducted on mice with the influenza virus as a model organism, researchers are confident that their observations also hold true for humans.
Cytokine storms are also suspected to be the main cause of death during the 1918 Spanish Flu pandemic, whose death toll may have reached 100 million. Incidentally, deaths were weighed more heavily towards people with healthy and uncompromised immune systems, because of their ability to generate stronger immune responses with dramatic spikes in cytokine levels.