HFMD is not a disease that can only be acquired once, but many times. Some patients with severe disease can even get it 2-3 times a year, but this is relatively rare, and the vast majority of patients can only get it once a year at most. The pathogens of HFMD are many viruses, including echovirus, coxsackie virus and enterovirus. There are many types of these viruses, and after a virus infects the body and causes HFMD, the virus can no longer infect the body and cause HFMD, but other viruses can still infect and cause HFMD. However, other viruses can still cause HFMD. In addition to causing HFMD, these viruses can also cause herpes pharyngitis. In addition to causing these two diseases, some of them can also cause insidious infections with no symptoms, and most enterovirus infections are insidious, with relatively few symptoms of HFMD.