Despite early comparisons between COVID-19 and influenza, coronavirus was never going to be just another flu. It comes from a different family of viruses and it has proven far more pernicious and unpredictable. Even so, “cytokine storms,” where the immune system turns on the body by overreacting to a virus, were widely regarded as playing a critical role in 1918 influenza pandemic.
Not all historians and scientists agree that cytokine storms led to as many deaths during the 1918 flu, and now a new study questions just how critical a factor they have been in COVID-related fatalities. So how large a part have these potentially fatal hyperinflammatory immune responses played in the 2020 coronavirus pandemic, and the flu pandemic more than a century ago?
Fewer than 5% of the COVID-19 patients in a new study, including some of the sickest individuals, had the life-threatening, hyperinflammatory immune response known as a ‘cytokine storm.’
Some 500 million people, or one-third of the world’s population, became infected with the 1918 Spanish flu. An estimated 50 million people died worldwide, with about 675,000 deaths occurring in the U.S., according to the Centers for Disease Control and Prevention. As of Sunday, nearly 54 million people worldwide contracted COVID-19, with 1.3 million deaths, 245,600 of which were in the U.S.
These scientists aimed to find out. Most adults with moderate-to-severe COVID-19 have a suppressed viral immune response when compared to those suffering from influenza, according to research published Saturday by scientists at St. Jude Children’s Research Hospital in Memphis, Tenn., and Washington University School of Medicine in St. Louis, Mo.
“Fewer than 5% of the COVID-19 patients in this study, including some of the sickest individuals, had the life-threatening, hyperinflammatory immune response known as cytokine storm syndrome. Cytokines are small proteins secreted by blood cells that help coordinate the immune response and trigger inflammation,” it found.
“We did identify a subset of COVID-19 patients with the broadly upregulated array of cytokines, which is a hallmark of cytokine storm,” said co-author Paul Thomas, Ph.D., a member of the St. Jude Department of Immunology. “But, overall, the average person with COVID-19 c even patients with moderate-to-severe disease — had less inflammation than the average person with flu.
He said patients would benefit from a rapid, reliable and inexpensive test to measure cytokines and identify those most likely to benefit from immunosuppressive treatment. “The findings suggest that treatment suppressing inflammation might only be effective in that minority of patients with the hyperinflammatory profile,” Thomas added.
A hallmark of some viruses: A surge of immune cells and their activating compounds (known as “cytokines”) effectively turned the body against itself, led to an inflammation of the lungs, severe respiratory distress, leaving the body vulnerable to secondary bacterial pneumonia. It was seen as one reason why seemingly healthy people were so hard hit by the 1918 flu.
The research included 168 adults with COVID-19, 26 adults with influenza and…