The fecal–oral route (also called the oral–fecal route or orofecal route) describes a particular route of transmission of a disease wherein pathogens in fecal particles pass from one person to the mouth of another person. Main causes of fecal–oral disease transmission include lack of adequate sanitation (leading to open defecation), and poor hygiene practices. If soil or water bodies are polluted with fecal material, humans can be infected with waterborne diseases or soil-transmitted diseases. Fecal contamination of food is another form of fecal-oral transmission. Washing hands properly after changing a baby's diaper or after performing anal hygiene can prevent foodborne illness from spreading. The common factors in the fecal-oral route can be summarized as five Fs: fingers, flies, fields, fluids, and food. Diseases caused by fecal-oral transmission include typhoid, cholera, polio, hepatitis and many other infections, especially ones that cause diarrhea.

Background

Although fecal–oral transmission is usually discussed as a route of transmission, it is actually a specification of the entry and exit portals of the pathogen, and can operate across several of the other routes of transmission. Fecal–oral transmission is primarily considered as an indirect contact route through contaminated food or water. However, it can also operate through direct contact with feces or contaminated body parts, such as through anal sex. It can also operate through droplet or airborne transmission through the toilet plume from contaminated toilets.

F-diagram

The foundations for the "F-diagram" being used today were laid down in a publication by the World Health Organization (WHO) in 1958. This publication explained transmission routes and barriers to the transmission of diseases from the focal point of human feces. Modifications have been made over the course of history to derive modern-looking F-diagrams. These diagrams are used in many sanitation publications. They are set up in a way that fecal–oral transmission pathways are shown to take place via water, hands, arthropods and soil. To make it easier to remember, words starting with the letter "F" are used for each of these pathways, namely fluids, fingers, flies, food, fields, fomites (objects and household surfaces). Rather than only concentrating on human feces, feces from other animals should also be included in the F-diagram. The sanitation and hygiene barriers when placed correctly prevent the transmission of an infection through hands, water and food. The F-diagram can be used to show how proper sanitation (in particular toilets, hygiene, handwashing) can act as an effective barrier to stop transmission of diseases via fecal–oral pathways.

Examples

Transmission

The process of transmission may be simple or involve multiple steps. Some examples of routes of fecal–oral transmission include:

Prevention

One approach to changing people's behaviors and stopping open defecation is the community-led total sanitation approach. In this process "live demonstrations" of flies moving from food to fresh human feces and back are used. This can "trigger" villagers into action.

Diseases

The list below shows the main diseases that can be passed via the fecal–oral route. They are grouped by the type of pathogen involved in disease transmission.

Bacteria

Viruses

Protozoans

Helminths

Related diseases

Waterborne diseases are diseases caused by pathogenic microorganisms that most commonly are transmitted in contaminated fresh water. This is one particular type of fecal-oral transmission. Neglected tropical diseases also include many diseases transmitted via the fecal-oral route.