Detection of Cryptosporidium parvum in locally manufactured yoghurt and Kareish cheese

Abstract

C ryptosporidium parvum is an important zoonotic parasite causing severe diarrhea in humans and young animals. Fifty milk products (25 Baladi yoghurt and 25 Kareish cheese) were tested for detection of C. parvum oocysts. The prevalence of C. parvum in yoghurt was 44%, 36% and 12% by microscopic examination, experimental infection and PCR, respectively. There is a statistical significant difference of C. parvum in yoghurt between microscopic examination and PCR as well as between experimental infection and PCR. While, its prevalence in Kareish cheese was 24%, 44% and 20% by microscopic examination, experimental infection and PCR, respectively. No statistical significant difference of C. parvum were detected in Kareish cheese between microscopic examination, experimental infection and PCR. Microscopic examination of prepared yoghurt and Kareish cheese smears and experimentally infected rats fecal smears showed the spherical shape of C. parvum oocysts (4-6μm). A banana shape of C. parvum sporozoite (3.2x1.4μm) was found in fecal smear of experimentally infected rat by contaminated yoghurt. Meanwhile, the PCR identified the specific Actin gene of C. parvum in 3 yoghurt and 5 Kareish cheese samples. From the obtained results, it could be concluded that C. parvum oocysts remain viable in locally made milk products.