Skip to main content
ARS Home » Research » Publications at this Location » Publication #184069
Title: DETECTION OF CRYPTOSPORIDIUM PARVUM OOCYSTS ON FRESH VEGETABLES AND HERBS USING ANTIBODIES SPECIFIC FOR A C. PARVUM VIRAL ANTIGEN.

Author
item KNIEL, K - U DELAWARE, NEWARK DE
item JENKINS, MARK - 1265-40-00

Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/21/2005
Publication Date: 5/29/2005
Citation: Kniel, K.E., Jenkins, M.C. 2005. Detection of cryptosporidium parvum oocysts on fresh vegetables and herbs using antibodies specific for a c. parvum viral antigen. Journal of Food Protection. 68:1093-1096.

Interpretive Summary: Cryptosporidiosis is an intestinal disease of humans and animals caused by the protozoan parasite Cryptosporidium parvum. The disease is prevalent in young calves, which suffer weight loss associated with diarrhea and inappetance. There are no approved drugs or disinfectants available to treat infected individuals or destroy the parasite. One method to prevent infection is to reduce exposure of humans and animals to the parasite by a combination of land management and water filtration. These management techniques rely on sensitive methods to detect the parasite in water. All of the techniques that are presently used to detect C. parvum oocysts are neither sensitive nor specific enough to identify low numbers of organisms in water. The present study describes a dot-blot method that detects an obligate viral symbiont of the parasite. This virus, termed CPV, is present at 2000 particles per oocysts, and as such increases the sensitivity of detection by at least 1000-fold. In the present study, the technique was used to detect C. parvum oocysts on vegetables and herbs.

Technical Abstract: The purpose of this study was to determine if the viral symbiont of Cryptosporidium parvum (CPV) sporozoites could be used as a target for sensitive detection of the parasite in food samples. Polyclonal sera specific to the recombinant viral capsid protein (rCPV40) was used in a dot blot hybridization assay to detect oocysts recovered from green onions and cilantro. Small batches of chopped green onions and cilantro leaves were artificially contaminated with three different concentrations of oocysts: 10^6, 10^2, and 10^1. rCPV40 was superior in detecting oocysts compared with other antibodies directed toward total oocyst protein and oocyst surface antigens. This study provides evidence that CPV is an excellent target for sensitive detection of C. parvum oocysts in foods.