Aetiological agent of brucellosis is bacteria: Brucella abortus, Brucella melitensis and Brucella suis
Epidemiology
They are Gram-negative, aerobic, non-spore forming, short, oval, non-motile rods that grow optimally at 37°C and pH 6.6-7.4. They are heat labile.
Symptoms
Incubation period varies and can take several weeks or months. Continuous, intermittent or irregular fever, sweat, headache, chills, constipation, generalized aching, weight loss, and anorexia.
Mode of Transmission
Brucella abortus is found in cows, Brucella melintensis in sheep and goats while Brucella suis are found in pigs.
The disease is contracted principally from close association with infected animals and therefore an occupational disease of farmers, herdsmen, veterinarians and slaughterhouse workers.
Can also be contracted by consumption of milk and products made from unpasteurized milk such as fresh goat’s cheese (Quinn, et al., 2001).
Control and prevention
Heat treatment of milk (Pasteurization or sterilization); use of pasteurized milk for cheese production, ageing cheese for at least 90 days; thermal processing’ good hygiene practices during production and processing.
Other measures include: Vaccination of animals, eradication of diseased animals (testing and slaughtering). Consumers should avoid consumption of raw milk and cheese made with raw milk.
The occurrence of Brucellosis is worldwide with the exceptions of northern Europe where it occurs rarely. Prevalent in eastern Mediterranean areas, southern Europe, North and east Africa, central and southern Asia, Mexico, Central and South America.
The disease is often unrecognized and unreported. Case-fatality ratio is up to 2% if the disease is untreated.
References
- Quinn, P., Markey, B., Carter, M., Demelly, W., & Leonard, F. (2001). Veterinary Microbiology and Microbial Disease (8th ed.). Oxford, UK: Blackwell Publishing.
