Giardiasis is infection of the small intestine with the parasite Giardia lamblia. The disease is spread by drinking water or eating food contaminated with the parasite, or by direct contact with an infected person. Symptoms usually start about 1 to 2 weeks after infection.
They may include diarrhea with foul-smelling feces, flatulence, belching, abdominal cramps, bloating, loss of appetite, and nausea.
If symptoms last for more than about a week, weight loss and malnutrition may occur, due to insufficient nutrients being absorbed. Treatment with antibiotics usually clears up the infection within a few days.
The risk of infection can be reduced by good personal hygiene and by avoiding food or water that might be contaminated