Development of PCR-RFLP method to distinguish between Cryptosporidium parvum and C. hominis in Taiwan water samples.

Cryptosporidium, a protozoan pathogen that causes cryptosporidiosis has emerged as an important source of diarrheal illness among humans and animals. The current routine laboratory technique used for Cryptosporidium diagnosis is light microscopy with acid-fast staining but the technique has low efficiency and sensitivity for species-specific identification. Single PCR to amplify a 220 bp fragment of 18 S ribosomal DNA of C. parvum and C. hominis was developed. The restriction enzymes, TaqI and VspI, were used to distinguish between amplicons of human and bovine C. parvum genotype. Water samples, collected from Lo-Na, Ton-Pu, Ho-Ping, and Jen-Ai, Taiwan contained only bovine C. parvum genotype whereas in the Ton-Pu and Jen-Ai samples C. hominis was also present. Thus, the used of PCR-RFLP allowed successful identification of Cryptosporidium in water samples and differentiation between human and bovine species.