Fecal-oral transmission happens when an infected person's contaminated feces enters the body of another person. This can occur when an infected person's hands aren't washed properly after using the bathroom; anything they touch afterward, such as a doorknob, can become contaminated with bacteria and be picked up by someone else.

Faecal-oral transmission refers to the process whereby disease is transmitted via the faeces of an infected individual, to the mouth of a susceptible individual.

What is fecal-oral transmission? Fecal–oral transmission occurs when bacteria or viruses found in the stool of one child (or animal) are swallowed by another child. This is especially common in group-daycare settings, where fecal organisms are commonly found on surfaces and on the hands of providers. Usually, the contamination is invisible.

The fecal-oral route most commonly results in Norovirus and is the number one cause of foodborne illnesses. The FDA defines the fecal-oral route as “a means of spreading pathogenic microorganisms from feces produced by an infected host to another host, usually via the mouth; e.g., contact between contaminated hands or objects and the mouth.”

Fecal-oral transmission is usually associated with organisms that infect the digestive system. Microorganisms enter the body through ingestion of contaminated food and water. Inside the digestive system (usually within the intestines) these microorganisms multiply and are shed from the body in feces.