Brucellosis is a severe febrile disease caused by various members of the genus Brucella. Canine brucellosis occurs worldwide and is endemic to America, Asia, and Africa leading to infertility and abortion in dogs. The bacterium is equipped with a battery of virulence factors like Lipopolysaccharide (LPS), T4SS secretion system and BvrR/BvrS system which enable its survival as well as spread in the host. The clinical signs in male dogs include inflammation of epididymis, testis and prostate gland where chronic epididymitis and orchitis may lead to unilateral or bilateral atrophy of testis making them sterile. The females show mid to late term abortion accompanied by inodorous, brown to yellow genital discharge. Aborted fetuses are usually partially autolyzed, edematous, congested with hemorrhages in the subcutaneous abdominal region. Females may give birth to dead or weak puppies that may die within few days. Various serological diagnostic tests have been developed but there is no standardized protocol available. Isolation of bacteria from blood samples is considered as goldstandard but has less sensitivity. Many molecular tests have also been developed with varying sensitivity and specificity. Dogs can also infect humans but the prevalence is low and infection is acquired by direct contact with infected dogs or their blood or reproductive products. The symptoms in humans are nonspecific flu like and include fever, headache, back pain, chills/night sweats, undulant fever, and weakness which are easily misdiagnosed. Unlike dogs, human do respond well to antibiotic therapy and able to clear the bacterium after long-term treatment. The disease burden can be reduced by preventing unrestricted movement of reproductively intact dogs and by continuous testing of breeding animals and their offspring before sale. Sterilization of intact stray animals and euthanasia of infected dogs may also limit the disease spread as well as the level of infection in canine population.
