Human and animal brucellosis in the Sultanate of Oman: an epidemiological study

Abstract

Introduction: Brucellosis is an infectious disease caused by direct contact with infected animals or animal products contaminated with Brucella. Brucella is a Gram-negative aerobic coccobacillus that infects different types of animals and is considered to be an important zoonotic disease. Methodology: Brucella were isolated from blood samples and identified following biochemical tests and agglutination with A and M monospecific antisera. Furthermore, Brucella antibody titers of the tested sera were obtained by the microtiter agglutination method (MAM). Results: The main Brucella species isolated in Oman was B. melitensis. However, in countries bordering Oman and their neighboring countries, both B. melitensis and B. abortus have been isolated and identified. A total of 412 human patients with suspected cases of brucellosis were admitted to the Department of Communicable Disease Surveillance and Control in the Dhofar Governorate for diagnosis and treatment. During the year 2015, a total of 343 human cases were positively diagnosed with brucellosis in the Dhofar Governorate. During the years 2015 to 2019, a total of 10,492 animals were examined in different Governorates of Oman for brucellosis. The results indicated that 1161 (11%) animals were serologically positive for brucellosis. Conclusions: The results of this study confirmed that Brucella melitensis is the main species responsible for human brucellosis in Oman. It was not surprising that the Dhofar Governorate exhibited a high percentage of infected patients since it is culturally acceptable to drink raw camel milk (unpasteurized), unlike cow milk which is pasteurized.