Public health emergencies refer to outbreaks of infectious diseases that could severely endanger public health, group diseases of unknown causes, severe food poisoning, occupational poisoning and other incidents that could cause serious consequences for public health.
There are various ways to classify public health emergencies, such as diseases caused by biological pathogens, food poisoning events, poisoning caused by toxic and harmful substances, deaths or harm caused by poisoning, natural disasters, deaths caused by accidents and diseases or deaths from unknown causes.