HFMD is an infectious disease caused by enteroviruses, most of which are enterovirus 71, and occurs mostly in children under the age of five. The main symptom of mild HFMD is a rash that appears as small blisters the size of rice grains to green beans with a red halo, seen on the palms of the hands and toes as well as on the buttocks and inner thighs. Sometimes the blisters in the mouth can form ulcers that interfere with eating due to pain. Some patients may also experience fever, weakness, and poor appetite, which are all manifestations of mild cases. Only a small number of patients will experience severe cases, and those with severe cases will develop meningitis, encephalitis, encephalomyelitis, and pulmonary edema.