Nearly 230 Idaho residents have contracted a waterborne parasite this year, along with hundreds of others across the Rocky Mountain West. Fifty six cases were reported in Colorado in August, which is more than four times the usually number of cases reported that time of year. Other western states such as Wyoming, Kansas, and North Dakota have also seen an increase this summer.
Cryptosporidium species have been found in a variety of hosts, including mammals, birds and reptiles. Waterborne outbreaks have been associated with contamination of municipal water and exposure to contaminated swimming pools. In these most recent cases of Cryptosporidium, the most common source of the infection (68%) reported swimming in pools and 35% reported swimming in natural water, such as lakes and streams.
Transmission in humans can also occur from farm livestock, including animals found in petting zoos, or pets. This parasite is excreted in feces, and person-to-person transmission can easily occur in childcare centers. It can also be a common cause of traveler’s diarrhea. Because the form of this parasite is resistant to chlorine, many sand filters used in swimming pools are ineffective in removing cryptosporidium from contaminated water.
Symptoms can range from frequent non-bloody watery diarrhea, abdominal cramps, fatigue, vomiting, weight loss and anorexia, to no symptoms at all. In those with poor immune systems (HIV, on chemotherapy, etc), severe diarrhea can develop leading to malnutrition, dehydration and death. It lasts an average of 10 days and is treated with anti-parasitic drugs such as Nitazoxanide. Probiotics are also recommended during the coarse of treatment.
Please contact your health practitioner if you have any symptoms of diarrhea to rule out this infectious parasite. Do not swim until 2 weeks after the resolution of your symptoms, and diapered children should not go to daycare until their diarrhea has resolved.