Sensitivity and Specificity of Dot Blot Method for Diagnosis of Cryptosporidium Infection

Diagnosis of cryptosporidiosis is based on the use of the routine microscopic methods, but these methods possess poor sensitivity and also need an expert technician. The aim of the present study was to determine sensitivity and specificity of dot blot method for diagnosis of bovine cryptosporidiosis.
In this study 131 fecal samples were collected from suckling calves during summer 2014. The collected samples were concentrated using formalin ether method. The samples were then examined by modified-Ziehl-Neelsen (mZN) and finally all samples were examined by dot blot methods.
Findings: Oocysts of Cryptosporidium spp. were found in 40 (30.5%) out of 131 fecal samples using mZN staining method but 49 (37.4%) of the samples were positive for Cryptosporidium antigen using dot blot method. No significant differences were observed among the results of the two methods and the sensitivity and specificity of dot blot calculated as 87 % and 86%, respectively.
Based on the results of the present study, dot blot method showed rather equal performance as modified-Ziehl-Neelsen method.