storms were responsible for the disproportionate number of healthy young adult deaths during the 1918 influenza pandemic, which killed an estimated 50 million people worldwide. In this case, a healthy immune system may have been a liability rather than an asset. Preliminary research results from Taiwan also indicated this as the probable reason for many deaths during the SARS epidemic in 2003. Human deaths from the bird flu H5N1 usually involve cytokine storms as well. Cytokine storm has also been implicated in hantavirus pulmonary syndrome. In 2006, a study at Northwick Park Hospital in England resulted in all 6 of the volunteers given the drug theralizumab becoming critically ill, with multiple organ failure, high fever, and a systemic inflammatory response. Parexel, a company conducting trials for pharmaceutical companies claimed that theralizumab could cause a cytokine storm—the dangerous reaction the men experienced. Relationship to COVID-19 During the COVID-19 pandemic, some doctors have attributed many deaths to cytokine storms. A cytokine storm can cause the severe symptoms of acute respiratory distress syndrome (ARDS), which has a high mortality rate in COVID-19 patients. SARS-CoV-2 activates the immune system resulting in a release of a large number of cytokines, including IL-6, which can increase vascular permeability and cause a migration of fluid and blood cells into the alveoli leading to such consequent symptoms as dyspnea and respiratory failure. In an autopsy study from Karolinska Hospital, 29 pleural effusions of deceased COVID-19 patients, were analyzed using Olink® Inflammation and Organ Damage panels. Out of 184 protein markers, 20 markers were raised significantly in COVID-19 deceased patients. A group of markers showed over-stimulation of the immune system, including ADA, BTC, CA12, CAPG, CD40, CDCP1, CXCL9, ENTPD2, Flt3L, IL-6, IL-8, LRP1, OSM, PD-L1, PTN, STX8, and VEGFA; furthermore, DPP6 and EDIL3 indicated damage to arterial and cardiovascular organs. The higher mortality has been linked to the effects of ARDS aggravation and the tissue damage that can result in organ-failure and/or death. ARDS was shown to be the cause of mortality in 70% of COVID-19 deaths. A cytokine plasma level analysis showed that in cases of severe SARS-CoV-2 infection, the levels of many interleukins and cytokines are highly elevated, indicating evidence of a cytokine storm. Additionally, postmortem examination of patients with COVID-19 has shown a large accumulation of inflammatory cells in lung tissues including macrophages and T-helper cells. Early recognition of a cytokine storm in COVID-19 patients is