Sample date: April 17, 2014

Partly cloudy. Wind south 20 km/h gusting to 40 becoming light this evening. Wind becoming south 20 after midnight. Low plus 5.


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Safe Water

Elevated Fluoride Levels in Drinking Water

Small Drinking Water Systems


This page was reviewed or revised on Thursday, November 12, 2009 5:08 PM

What is Cryptosporidium?

Cryptosporidium is the name of an intestinal infection caused by a parasite. This parasite affects both man and animals such as poultry, fish, cats and dogs as well as livestock. It is commonly found in lakes and rivers, especially if the water is contaminated with human or animal waste.

This parasite is found all over the world and has caused several large outbreaks of gastrointestinal illness with symptoms such as diarrhea, nausea and/or vomiting and abdominal cramps. Those particularly susceptible to this parasite are young children under the age of 2 years, those who handle animals, people travelling to areas where the sanitation may not be very good, healthcare workers (particularly in a day care setting), as well as those with immune system impairments. Outbreaks have also been associated with drinking water supplies and contaminated lakes and swimming pools.

How is Cryptosporidium Spread?

The parasite is passed from person to person and from animal to person through the faecal-oral route (i.e. not washing hands after using the toilet or handling animals). It is also transmitted through drinking contaminated water or eating contaminated food. Because this parasite is very resistant to several disinfectants including chlorine bleach and because Cryptosporidium can survive in the environment for long periods of time, it can be very difficult to control.

What are the Symptoms?

It takes anywhere from 1 to 12 days after ingesting the parasite (or its eggs) for symptoms to begin. Symptoms may include severe, watery diarrhea, lack of appetite, cramping and possible vomiting, fatigue and fever. Symptoms in a healthy person may come and go but usually disappear in 30 days. It is even possible to carry the parasite and have no symptoms at all.

How Can Cryptosporidium Be Prevented?

  • Wash hands carefully after using toilet or handling animals.
  • Dispose of human and animal waste properly.
  • Persons with diarrhea should not work in a restaurant or health care facility until diarrhea has stopped for at least 24 hours.
  • Children with diarrhea should be excluded from daycare centers.
  • Boil drinking water supplies for one minute and be sure it is filtered if the possibility of contamination exists