Development and Preliminary Evaluation of a Nanoparticle-Assisted PCR Assay for the Detection of Cryptosporidium parvum in Calves

Simple Summary Accurate and rapid detection of Cryptosporidium parvum is useful for the prevention and control of cryptosporidiosis in humans and animals. This study developed a nano-PCR assay for the rapid detection of C. parvum in calves for the first time, and it was ten-fold more sensitive than the normal PCR assay and had no cross-reaction with other common gastrointestinal pathogens. Further analyses of faecal samples of calves indicated potential usage of the nano-PCR assay in clinical settings. C. parvum is an important diarrheal pathogen in humans and animals, especially in young hosts. To accurately and rapidly detect C. parvum infection in calves, we established a nano-PCR assay targeting the cgd3_330 gene for the specific detection of C. parvum. This nano-PCR assay was ten times more sensitive than that of the normal PCR assay by applying the same primers and did not cross-react with C. andersoni, C. bovis, C. ryanae, Balantidium coli, Enterocytozoon bieneusi, Giardia lamblia, and Blastocystis sp. To further test the nano-PCR in clinical settings, a total of 20 faecal samples from calves were examined by using the nano-PCR, the normal PCR, and the nested PCR assays. The positive rates were 30% (6/20), 30% (6/20), and 25% (5/20) for the nano-PCR, the normal PCR, and the nested PCR assays, respectively, indicating that the nano-PCR and the normal PCR assays had the same positive rate (30%). Taken together, the present study could provide a candidate method for the specific detection of C. parvum infection in calves in clinical settings.