Test your well water regularly and avoid drinking untreated water, such as water from lakes and streams.
Restrict access to contaminated areas. Clean them thoroughly, disinfect and dry them. You can use bleach.
The parasite that causes giardiasis is resistant to most disinfectants. Adding chlorine to drinking water or to swimming pools is not enough to kill it.
Humans can be contaminated by domestic or wild animals, especially beavers. Infected animals that do not show any symptoms can still transmit the disease.
Giardiasis can be diagnosed 3 to 24 days after contamination. Signs appear most frequently within 7 to 10 days.
Giardiasis can be transmitted through direct contact with sick people or animals, via the fecal-oral route. For example, you can contract the disease if you smoke after touching an infected animal.
A person can also contract the disease by drinking untreated water or eating a vegetable from a garden fertilized with contaminated manure.
The parasite is also transmitted in areas polluted with excrement, such as a watercourse, grassland or garden.
People in good health generally do not show any symptoms. Visible symptoms include diarrhea, intestinal cramps, abdominal bloating and weight loss. The disease can last from several days to several weeks and reappear even after recovery.