Science and Technology Daily, Beijing, May 9th, according to a paper published in the latest issue of "Journal of Clinical Research", researchers at Northwestern University Feinberg School of Medicine applied machine learning techniques to medical data and found that patients who could not be cured Secondary bacterial pneumonia is a key driver of death in patients with 2019-nCoV infection, and may even exceed the fatality rate of the viral infection itself. They also found evidence that SARS-CoV-2 infection does not cause the "cytokine storm" that has traditionally been thought to cause death.

The researchers found that secondary bacterial infections of the lungs were extremely common among patients infected with the new coronavirus, affecting nearly half of those requiring mechanical ventilatory support. In other words, nearly half of COVID-19 patients will develop secondary ventilator-associated bacterial pneumonia.

The study analyzed 585 patients with severe pneumonia and respiratory failure in the intensive care unit of Northwestern Memorial Hospital in the United States, 190 of whom were new crown patients. The researchers developed a new machine learning method called CarpeDiem, based on data from daily rounds recorded by the ICU team, to understand how complications such as bacterial pneumonia affect the course of the disease.

Those who were cured of secondary pneumonia were more likely to survive, while those who were not cured were more likely to die, the researchers said. The study data showed that the mortality rate associated with the new coronavirus itself was relatively low, but other things that happened during the ICU, such as secondary bacterial pneumonia, made the mortality rate increase.

The findings also disprove the cytokine storm theory. "If cytokine storms were indeed responsible for prolonged hospitalizations in patients with COVID-19, we should have seen frequent transitions to states characterized by multi-organ failure, but this was not the case," the researchers said.

The importance of bacterial superinfection of the lungs as a cause of death among COVID-19 patients has been underestimated, researchers say. This study highlights the importance of preventing, searching for, and aggressively treating secondary bacterial pneumonia in patients with severe pneumonia, including those with 2019-nCoV infection.