Outbreaks common in western U. S. and elsewhere. Idaho and Utah were hard hit this year. The Mayo Clinic estimates about 3000 cases/year in the U. S., but many cases are unreported. Most people have contracted the parasite at sometime in their lives.

In 1993, there were over 450,000 cases in Milwaukee but only 4 fatalities. In Nevada there were 16 fatalities in 78 cases, but it is suspected most cases went undetected (Las Vegas area, many visitors). Only serious local cases seem to have been reported.

People who contract the parasite usually recover in a month. Most people suffer diarrhea which lasts a couple of weeks. Those with very weak immune systems are seriously affected.

Microfiltration helps, but 100% elimination takes time. Water recirculation in pools contributes to the problem; chlorination is not always sufficient.

The Mayo Clinic suggests drinking boiled and filtered water. It also suggests that children should not wear diapers in wading pools, and other measures.
See Cryptosporidium