Pictures of early symptoms of hand, foot and mouth disease (detailed explanation of early symptoms of hand, foot and mouth disease) Hand, foot and mouth disease is one of the common infectious diseases in children. The main routes of infection are droplet transmission and contact transmission. The initial symptoms of the disease are mild and difficult to detect. This article will elaborate on the causes, early symptoms, picture display, and preventive measures of hand, foot and mouth disease. The cause of hand, foot and mouth disease is mainly enterovirus infection. The virus can be transmitted through the respiratory tract, mouth, feces, etc.