A condition in which the blood and tissues are flooded by the excessive release of cytokines that can, in some cases, be fatal.
In optimal quantities, cytokines effectively regulate the immune response to fight off infections and other diseases. But in some cases, an excess of these proteins is produced by the body which can trigger over-inflammation, high fever, severe fatigue, and nausea. In COVID-19, cytokine storms may be severe or life-threatening and lead to multiple organ failure.
Cytokine storms can occur in other diseases such as SARS and multiple sclerosis.