Prevalence of Cryptosporidium parvum infections in weaned piglets and fattening porkers in Kanagawa Prefecture, Japan.

Fecal samples from 232 weaned piglets (1 and 3 months old) and 252 fattening porkers (6 months old) in 8 stock-raising farms located in Kanagawa Prefecture, Japan, from June 1998 to June 2000 were examined to determine the prevalence of Cryptosporidium infection. Detection of oocysts was performed using the ethyl acetate fecal concentration method and immunofluorescent staining. C. parvum oocysts were identified in 77 (33.2%) 1-3 months old weaned piglets from four farms. The odds of excreting among 1-3 months old piglets were more than 100 times greater than among 6 months old porkers (95% confidence interval: 17-902). This strongly suggests that weaned piglets are important reservoirs of pathogenic microbes whose potential contamination of drinking water has epidemiological implications for human health.