A pathogen carrier is a person who carries pathogens such as viruses or bacteria that have invaded the human body without causing a clinical infection, and a person who carries these viruses or bacteria is called a pathogen carrier. The invading pathogens are able to remain at the site of invasion or enter more distant organs to continue to grow and multiply, but the person does not appear to have any disease state. This is mainly due to the fact that the body’s ability to resist and the pathogen’s ability to invade are not comparable and are in a state of contention. According to the period in which the infection occurs, it can be categorized into latent carriers as well as recovering carriers. Generally speaking, if the body carries the pathogen for a duration shorter than 3 months, it is called an acute pathogen carrier, and if it is longer than 3 months, it is called a chronic carrier. However, there are exceptions, such as hepatitis B virus carriers, who have been carrying the hepatitis B virus for more than 6 months before they are called chronic carriers.