How Diseases Spread Through the Fecal-Oral Route

Proper handwashing is your best defense

Viruses, bacteria, fungi, and parasites spread from person to person, sometimes causing diseases as they move in and out of people's bodies along various routes. When the disease spreads through the fecal-oral route, it means that contaminated feces from an infected person are somehow ingested by another person.

For obvious reasons, this almost never happens deliberately. Usually, the situation occurs when an infected person might forget to properly wash their hands after using the toilet. Anything they touch afterward might be contaminated with microscopic germs that other people may encounter.

Mother squeezing hand sanitizer onto little daughter's hand outdoors to prevent the spread of viruses during the Covid-19 health crisis
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A person infected with a disease transmitted through the fecal-oral route uses the bathroom and then opens the restroom door. Another person comes along, touches that contaminated doorknob, and then nervously bites on a fingernail before washing their hands properly. The microbe is spread through the fecal-oral route.

Microbe Transmission

Food workers must be extra diligent about hand hygiene because they are in a position to easily spread a fecal-oral disease through the food they prepare to anyone who eats it. In many cases of foodborne illness outbreaks, poor hand hygiene is the precipitating factor.

While poor hand washing is a major cause of fecal-oral contamination, there are other equally important considerations. Here are other ways microbes use the fecal-oral route to cause disease:

  • Drinking water contaminated with raw sewage.
  • Eating shellfish (such as oysters and clams) that have been harvested from contaminated water.
  • Eating raw fruits or vegetables washed in contaminated water.
  • Sexual activity that allows direct mouth-to-anus contact or indirect contact (touching the mouth to something that touched the anus).
  • Swimming pools that aren't properly disinfected.

Viral Hepatitis

There are many microbes that can be passed along through the fecal-oral route, including two of the hepatitis viruses, hepatitis A and hepatitis E. The other hepatotropic viruses spread by direct contact with infected blood, such as from sharing used needles, bodily fluid, or through childbirth.


Good handwashing is a tremendously effective way to break the fecal-oral cycle. Other important tools for preventing the spread of disease through fecal-oral transmission include:

  • Using instant hand sanitizers when soap and water are not available
  • Practicing safe and careful food-handling practices
  • Avoiding ingestion of water in pools or from other non-potable sources
  • Using disposable towels
  • Cleaning or disinfecting commonly touched, infected surfaces such as doorknobs, faucet handles, remote controls, etc.

Frequently Asked Questions

  • What diseases can be spread through the fecal-oral route?

    A few diseases that can be spread through the fecal-oral route include hepatitis A, hepatitis E, cholera, adenovirus, and E. coli. These diseases occur due to the viruses, bacteria, fungi, and parasites that can spread through fecal-oral transmission.

  • How does fecal-oral transmission happen?

    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. Eating foods that were washed or harvested from contaminated water can also spread disease in a similar manner.

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Centers for Disease Control and Prevention (CDC). Viral Hepatitis.

  2. Centers for Disease Control and Prevention. Food Worker Handwashing and Restaurant Factors.

  3. Centers for Disease Control and Prevention. Food & water precautions.

  4. Bonadonna L, La rosa G. A review and update on waterborne viral diseases associated with swimming pools. Int J Environ Res Public Health. 2019;16(2). doi:10.3390/ijerph16020166

  5. John Hopkins Medicine. Viral hepatitis A and E.

Additional Reading

By Charles Daniel
 Charles Daniel, MPH, CHES is an infectious disease epidemiologist, specializing in hepatitis.