Just how fatal is the coronavirus? Experts are still struggling — months after the virus emerged — to answer that question. Epidemiologists trying to pin down a fatality rate for covid-19 say they simply lack enough reliable data. On Monday, for example, China’s Center for Disease Control and Prevention published a study with the best and most conclusive statistics. Drawing on the patient records of 44,672 confirmed cases, Chinese researchers deemed the virus to have an overall fatality rate of 2.3 percent. “The problem is they basically just took the total number of deaths and divided it by number of cases,” said Caitlin Rivers, an epidemiologist at Johns Hopkins Center for Health Security. “It’s not exactly the ideal way to understand fatality rate because it doesn’t take the element of time into consideration.” The study didn’t take into account, for example, that the virus has a long incubation period, […]