Diseases transmitted through the gastrointestinal route can be transmitted through saliva, such as viral hepatitis A, viral hepatitis E and acute dysentery, cholera, typhoid, etc., which are representative of gastrointestinal infectious diseases, with the common feature that eating food contaminated by pathogens or drinking contaminated water can lead to infection of the body. In addition to digestive tract infectious diseases, diseases transmitted by droplets can also be transmitted by saliva, such as chickenpox, mumps, tuberculosis, etc. Transmission can be through sharing utensils or kissing, etc. To avoid transmission, meal sharing should be recommended.