During 2001, 198 cases of laboratory-confirmed Cryptosporidium parvum infection were reported (4.0 per 100,000 population). This is similar to the 197 cases reported in 2000 but represents a 14% increase from the median number of cases reported annually from 1996 to 2000 (median, 173 cases; range, 81 to 242).
Demographic characteristics of cases reported in 2001 were similar to previous years. The cryptosporidiosis rates in the Southeastern, West Central, Southwestern, and Central districts (12.0, 9.9, 7.8, and 7.5 cases per 100,000 population respectively), were significantly higher than the statewide rate. The Twin Cities metropolitan area had the lowest rate of cryptosporidiosis (1.1 cases per 100,000 population). Case-patients ranged in age from 3 weeks to 87 years, with a median of 9 years. Children less than 10 years of age accounted for 53% of cases, and children less than 5 years of age accounted for 35%. Fifty-eight percent of cases had stool samples collected during July through October. Sixteen percent of cases were hospitalized; four (2%) cases were known to be HIV-positive.
Two outbreaks of cryptosporidiosis were identified in 2001, accounting for 11 confirmed cases. One outbreak was associated with a child daycare facility, and one was associated with contact with ill calves at a farm day camp.