Symptoms usually start 5 to 28 days after infection. Not all people who are infected have symptoms. But, all people who are infected can transmit the disease.
Symptoms may include:
- Diarrhea , acute or chronic
- Loose, greasy, foul-smelling stools
- Abdominal pain or cramps
- Nausea or vomiting
- Weight loss
- Mild fever (rare)
The doctor will ask about your symptoms and medical history, and perform a physical exam. Tests may include:
- Laboratory exam of several (usually three) stool samples
- Stool testing for Giardia proteins (called the Giardia antigen test)
- In some cases, testing of a fluid or tissue sample from the intestine
If you are diagnosed with giardiasis, everyone living in your household should be tested for infection as well.