Polymerase chain reaction for the direct detection of Brucella spp. in milk and cheese

A polymerase chain reaction test was developed to detect Brucella spp. dire ctly in milk and cheese and optimized using primers for the BSCP-31 gene. A total of 46 cheese samples produced with sheep and goats milk were assayed , and Brucella spp. was detected in 46% of them, especially in cheese made from sheep milk. This method is of remarkable epidemiologic interest becaus e it is an indirect test indicating the sanitary quality of milk used in da iry industries. The method showed good sensitivity and specificity. It is f aster and less expensive than the conventional bacteriological assays.