Eating something that someone else has eaten can cause disease transmission. Eating food together can be contagious when the person who eats it has an infectious agent of his or her own that can be transmitted through the digestive system. The transmission of pathogens requires the fulfillment of three elements: the source of infection, the means of transmission, and the susceptible population. Pathogens can spread through the air, droplets, respiratory tract and digestive system. Therefore, the act of eating together can result in the transmission of a disease when the person eating together has an infectious disease and the pathogen can be transmitted through the digestive tract. However, the specific transmission of disease and the chance of infection is still related to the individual’s physical condition and the amount of virus exposure. When susceptible people are in good health or have high levels of antibodies in their bodies, they are less likely to be infected. At the same time, when the amount of virus remaining in the common food is low and cannot cause direct infection in the body, it may not cause disease transmission. When there is a possibility of transmission of the disease in the living habits and daily diet, it is recommended to take personal protection and comprehensive prevention and control measures.