What is Cryptosporidiosis?
Cryptosporidiosis (crip-toe-spor-id-I-o-sis) is a disease caused by cryptosporidium parvum which, as late as 1976, was not known to cause disease in humans. Cryptosporidium is a single-celled, protozoan parasite found in the waste of humans and animals (such as cattle, sheep, raccoon, beaver, muskrat) infected with the organism. It can be found in the environment in rivers, lakes, streams and reservoirs. Until recently little has been known about its disease producing capabilities. Cryptosporidium is too small to be seen with the naked eye.

How is Cryptosporidiosis Spread?
Infection with the disease can occur via ingestion of contaminated food or water. The disease is easily spread through hand-to-mouth contact. A person can become infected by drinking contaminated water, eating raw or undercooked food, direct contact with the droppings of infected animals or stool of infected humans, or hand-to-mouth transfer of the organism from surfaces that may have become contaminated with microscopic amounts of stool from an infected person or animal. The infectious form of the parasite is called oocyst (o-o-cysts), which is an egg-like form of the parasite.

What are the Symptoms of Cryptosporidiosis?
The symptoms of cryptosporidiosis are diarrhea, headache, abdominal cramps, nausea, vomiting and low-grade fever. Onset typically occurs within 2 to 10 days after exposure. At present there is no treatment for cryptosporidiosis. In an otherwise healthy person, cryptosporidiosis symptoms usually last 1 to 2 weeks by which time the body's immune system is able to overcome the infection.

In persons with compromised immune systems, such as those persons who have been receiving chemotherapy treatment for cancer, people with AIDS or those taking immune suppressant drugs, and the very young or old, the infection may continue and become life-threatening. See your doctor to determine if symptoms are caused by cryptosporidium, and what actions to take.

Presence in Water Supplies
Cryptosporidium can enter water supplies via runoff from the watershed, cattle feed lots, grazing operations and direct discharge of waste, all of which represent significant contributors to contamination through runoff. Cryptosporidium can be transmitted by water and may be present in any unfiltered surface water. Cryptosporidium could also be present in poorly constructed wells that allow the direct and immediate entry of raw surface water.

Water Quality Testing
The DES laboratory does not analyze water samples for cryptosporidium. A partial list of commercial laboratories performing this test is given on page three of this document. Laboratory testing of water samples for cryptosporidium is very expensive and time consuming. The collection procedure consists of filtering approximately 500 gallons of water through a cartridge type particle filter, a process which takes approximately six hours. When collection is completed, the cartridge sample must be refrigerated and delivered to the laboratory within 24 hours. Actual processing of the cartridge by the laboratory takes additional hours. Commercial laboratory testing for cryptosporidium typically costs hundreds of dollars per sample.

Well Construction
Cryptosporidium are approximately twice as large as coliform organisms. Thus if your well can resist the entry of minute organisms like coliform then it certainly should be able to resist larger organisms like cryptosporidium. Rather than conduct costly water testing for cryptosporidium, DES recommends the following more practical approach to determining whether your well is at risk relative to cryptosporidium.

1. Inspect your well for proper construction. Carefully inspect the cover and exposed sides of your well for a broken casing or leaking cover. Look for any construction weaknesses where animal waste, insects, or unfiltered surface water could enter the well. Repair as necessary. If you need further information concerning good well construction, please request DES fact sheets concerning "Bedrock Well Design" WD-WSEB-1-2 or "Dug Well Design" WD-WSEB-1-4.
2. Once the well's defects have been repaired, and the well has been disinfected, take samples for coliform bacteria. These samples should be taken after a heavy rain and spaced out over weeks or months. We suggest taking 3 or 4 coliform bacteria samples and evaluating the results.

If Bacteria Is Present
Where coliform bacteria are detected, the well must be judged as at risk to cryptosporidium and other potentially harmful organisms. In such cases the well's construction or aquifer's filtration must be further evaluated.

Where the well's construction is judged to be sufficient, but bacteria still continue to be present, other actions should be taken. Options include drilling another well or installing a continuous disinfection system. Please note that cryptosporidium is particularly hardy and very resistant to disinfection by chlorine. In addition, the weakness of disinfection is that on occasions the concentration of bacteria from the still unknown source may exceed the capability of the disinfection system, thus leaving the user unprotected.

FOR MORE INFORMATION
If you have further questions pertaining to your water supply please contact the DES' Water Supply Engineering Bureau at (603) 271-3139. If you have further questions concerning the disease cryptosporidiosis, please call the Health Risk Assessment Unit of the Department of Public Health at 271-4664. We would appreciate your comments on this fact sheet. For a list of all drinking water fact sheets, please request WD-WSEB-15-2. Drinking water fact sheets are available through the DES web site at: www.des.state.nh.us/ws.htm then select fact sheets. 4/03