The prevalence of Brucella abortus and Brucella melitensis in local cheese produced in Sarab city, Iran and its public health implication

Abstract

Brucellosis is an infectious disease caused by different species of Brucella. The main sources of human brucellosis for general population are dairy products prepared from raw milk. The aim of this study was to determine the prevalence of Brucella abortus and Brucella melitensis in unpasteurized cheese produced in Sarab city. For this purpose, a total of 1000 cheese samples were collected from Sarab city and its rural area from September 2006 till September 2007. Samples were cultured on selective Brucella agar and incubated at 37 C for a period of 2 weeks. Brucella species were confirmed by biochemical tests and then serological screening was performed by specific Brucella antisera. Overal, among 1000 samples which were examined by bacteriological tests, Brucella organisms were isolated from 22 samples (2.2%), seven of which (0.7%) were B. melitensis and the rest 15 positive samples (1.5%) were B. abortus. The prevalence rates of Brucella organisms in examined cheese samples in autumn, winter, spring, and summer were determined 2.42, 1.39, 2.5 and 2.62% respectively. This study revealed the public health hazard of local cheese produced in Sarab city.