ABSTRACT
Cryptosporidium, a zoonotic parasite with various hosts, is well recognized as pathogen in humans, particularly those with immune-suppression or immune-deficiency. The epidemiologic considerations for cryptosporidiosis emphasize on transmission of resistant oocystes via drinking water, vegetables, food, etc. The present study was undertaken to study the Cryptosporidium contamination in lettuce from different regions as a source of infection for human beings in Shiraz. In a descriptive-analytical study, the cryptosporidium contamination of 200 lettuce samples from four different regions was investigated during spring and summer, 2006. All samples were processed and examined using modified Ziel-Neilsen staining and also by a quantitative method for counting oocystes per sample. From a total of 200 samples, forty seven samples [23.5%] were positive. No significant difference was seen between contamination rate of lettuce and seasons, except for samples from Jahrom, where showed higher contamination rate in spring than summer. In addition, no significant difference was observed among oocytes count in different samples, except for lettuce from Ahwaz in summer with higher parasite intensity. Regarding to the high contamination of lettuce with Cryptosporidium, as well as to sanitary washing of vegetables before consumption, taking special procedures appear to be helpful for reducing the contamination rate at the farm level