Nonpathogenic (harmless) intestinal protozoa are single-celled parasites found in the intestine that do not cause illness. They are not harmful to the body, even in individuals with compromised immune systems.

The following are some examples of nonpathogenic (harmless) intestinal protozoa:

  • Entamoeba polecki
  • Chilomastix mesnili
  • Entamoeba hartmanni
  • Entamoeba dispar
  • Iodamoeba buetschlii
  • Entamoeba coli
  • Endolimax nana

Protozoa are exclusively present in the intestine’s lumen (cavity). They are also not present in the cells of the intestine and don’t scatter in other sections of the body.


Watery feces characterize protozoa infection, stomach bloating and cramping, nausea, exhaustion, and weight loss. Nonpathogenic (harmless) intestinal protozoa do not lead to disease. Other possible reasons for your symptoms must be looked into. Your doctor may test your feces for bacteria, viruses, or other parasites to establish if you are infected with a pathogen.


Your doctor may request a stool test if you experience diarrhea and other symptoms. Your healthcare professional will examine your health history and evaluate you by conducting an examination. Some laboratory tests may be done to assist in the diagnosis of parasitic infections and other noninfectious reasons for gastrointestinal symptoms:

  • Stool examination. This test detects parasites. Your healthcare practitioner may offer a container containing preservation fluid for your stool sample. It would be best if you waited to take your samples to your doctor’s office or lab to keep them refrigerated, not frozen.
  • Endoscopy. If the stool examination does not indicate the reason for your symptoms, your doctor may request this test. A unique camera on a tube serves to inspect your digestive system while you are sedated.

The presence of these protozoa in your stool indicates that you have previously been exposed to fecal matter by ingesting them, such as by drinking feces-contaminated water or food. This is known as fecal-oral transmission.


Because they do not cause illness, nonpathogenic (harmless) intestinal protozoa do not need treatment.

Preventative Measures

If you are still worried about these problems, even if they don’t cause disease, you may do a few things to lower your chances of acquiring a parasitic infection. Here are a few examples:

  • It is best to avoid drinking water from lakes, ponds, or streams.
  • People should avoid handling poop or pet litter when pregnant.
  • Eat only cooked foods.
  • Boil and filter the water before drinking.
  • Hands should be disinfected regularly.

Related Articles


Overview and FactsTypes and SymptomsDiagnosis & MedicationsOverview and Facts Tetralogy of Fallot is a congenital heart defect that affects the [...]


Overview and FactsTypes and SymptomsDiagnosis & MedicationsOverview and Facts Trichinosis, also known as trichinellosis, is a parasitic infection caused by [...]


Overview and FactsTypes and SymptomsDiagnosis & MedicationsOverview and Facts Trigeminal neuralgia is a neurological condition characterized by severe facial pain. [...]