In severe COVID-19 disease, the immune system becomes overactivated which generates excessive inflammation. Therefore, therapies that decrease immune system activity may improve the health of these patients.
Ye, Q., Wang, B. & Mao, J. The pathogenesis and treatment of the `Cytokine storm’ in COVID-19. Journal of Infection (2020). https://doi.org/10.1016/j.jinf.2020.03.037
10 April 2020
The immune system is responsible for defending the body against infections, including infection by SARS-CoV-2, the virus that causes COVID-19. The immune system clears infections by generating an ‘inflammatory response’, which causes cells of the immune system to move to the site of an infection (e.g. lungs) and kill the infectious agent. While inflammation is usually helpful, patients who have severe COVID-19 develop excessive inflammation, which can cause respiratory distress and multi-organ failure. Due to this, researchers are investigating whether treatments that control the immune system and decrease inflammation are helpful for patients with severe COVID-19. Corticosteroids are general anti-inflammatory medications, and their use in patients with severe COVID-19 has led to improved health. Additionally, medications that block key chemical signals needed to generate inflammation appear promising, either due to initial results showing their usefulness in treating severe COVID-19 or a proven track record in treating other diseases which involve excessive immune activity. Treatments that decrease immune system activity must strike delicate balance – while it is important to quell excessive inflammation, it is also important that patients retain enough immune system activity in order to clear the virus. Treatments that dampen immune system activity show preliminary promise in advanced COVID-19, in which patients’ immune systems are overactive, and further research is important to determine which specific treatments work best.
Summary by: Jacob Ferguson