Seropervelance detection of Coxiella burnetii antibodies in milk and serum of dairy cattle by recent methods

This study aimed to detect C. burnetii antibodies in milk and serum of dairy cattle using PCR compared with other immunological techniques namely IFAT and ELISA. These samples were collected from apparently healthy cows (n=300) from Giza, Fayoum and Beni Suief Governorates. Real-time PCR for detection of C. burnetii DNA was performed on samples using two individual PCR assays with specific primers and probes to increase specificity of the result using Roche kits. IFAT revealed detection of 6% IgM antibodies in milk and 7.3% in sera. While IgG was 10.6% of milk and 24% in sera. The main value of positive samples by ELISA test were 25.7%; in serum 34% and in milk 17.3%. These results showed that sensitivity and specificity of the ELISA test and IFAT were highly comparable. The result of Real time PCR from 77 positive samples of C. burnetii was 45.4%. The highest results for real time PCR recorded 57.1% in Beni Suief followed by 44% in Giza and 33.3% in Fayoum. It was concluded that the apparently healthy dairy cows are an important reservoir of C. burnetii infection. Investigations on C. burnetii using PCR as well as serological surveys of animals are important methods for diagnosis and control of Q-fever. Awareness is needed for animal owners, veterinarians, physicians and authorities.