Doctors noticed something else as well: patients who had no history of diabetes sometimes developed severe diabetic symptoms while battling COVID, and some remained diabetic after COVID resolved. According to a meta-analysis of eight studies published in late November, as many as 14 percent of hospitalized COVID patients developed what appeared to be “new onset” diabetes. In type 2 diabetes, the more common form, body cells have become less sensitive to insulin and beta cells are depleted or dysfunctional. Zimmet says that there is further evidence from postmortem studies of COVID patients showing the destruction of pancreatic beta cells. This treatment, too, is a reason that COVID patients may suddenly develop severe symptoms of diabetes.