The best way to prevent giardiasis is to wash your hands. This recommendation is so easy that people sometimes forget about it. Hand-washing is especially important:

• After you use the toilet (especially after a bowel movement).
• After you change a baby's diaper or when you take care of children who are still in the process of toilet training.
• When you take care of adults who are ill or who may have trouble controlling their urine or bowels.
• Before you prepare or handle food.

Also, avoiding oral-anal contact will help prevent transmission of giardia.