The 1st International Conference on Emerging Zoonoses, held in Jerusalem, Israel, focused on the global issue of brucellosis, a significant zoonotic disease. Brucellosis remains a major public health concern worldwide, with Brucella melitensis being the primary cause of human infection, despite the use of vaccines like Rev 1. Other species such as Brucella suis and Brucella abortus are also emerging as important causes of infection in both animals and humans. Recent isolations of Brucella strains from marine mammals have expanded the ecological range of the genus. Molecular genetic studies have shown that Brucella is phylogenetically related to Agrobacterium, Phyllobacterium, Ochrobactrum, and Rhizobium. Polymerase chain reaction and gene probe development are being explored for more effective typing methods. Brucella's pathogenicity is linked to the production of lipopolysaccharides, Cu-Zn superoxide dismutase, and other proteins that aid in intracellular survival. Protective immunity is conferred by antibodies to lipopolysaccharides and T-cell-mediated macrophage activation. Diagnosis relies on isolation of the organism and serologic tests, with enzyme immunoassay being widely used. Treatment involves tetracyclines, aminoglycosides, or quinolones, though no satisfactory vaccines are available. Recent research has identified promising attenuated purE mutants for vaccine development. Brucellosis has a complex epidemiology, with varying incidence across regions. It is particularly prevalent in the Mediterranean, western Asia, parts of Africa, and Latin America. The disease is primarily transmitted through consumption of contaminated foods and occupational exposure. Human-to-human transmission is rare. Prevention depends on controlling the disease in animals, with some success in eradicating bovine brucellosis in industrialized countries. However, Brucella melitensis remains challenging to control. Molecular genetics of Brucella has advanced significantly, revealing a genome of 2.37 × 10^9 daltons with high homology among species. The genus is classified as monospecific, though the old nomenclature is still used. The genome contains two chromosomes, and various genes are involved in pathogenicity and survival. Antigenic components include lipopolysaccharides, which are the main target of the immune response. Other proteins, such as ribosomal proteins, are also immunologically important. The mechanisms of Brucella pathogenicity involve intracellular survival, evasion of phagocytic responses, and production of inhibitors that prevent phagolysosome fusion. The bacteria can survive within macrophages by synthesizing specific proteins. The role of stress-induced proteins like HtrA and RecA is also being studied. Diagnosis relies on blood culture and serologic tests, with PCR and antigen detection methods under evaluation.The 1st International Conference on Emerging Zoonoses, held in Jerusalem, Israel, focused on the global issue of brucellosis, a significant zoonotic disease. Brucellosis remains a major public health concern worldwide, with Brucella melitensis being the primary cause of human infection, despite the use of vaccines like Rev 1. Other species such as Brucella suis and Brucella abortus are also emerging as important causes of infection in both animals and humans. Recent isolations of Brucella strains from marine mammals have expanded the ecological range of the genus. Molecular genetic studies have shown that Brucella is phylogenetically related to Agrobacterium, Phyllobacterium, Ochrobactrum, and Rhizobium. Polymerase chain reaction and gene probe development are being explored for more effective typing methods. Brucella's pathogenicity is linked to the production of lipopolysaccharides, Cu-Zn superoxide dismutase, and other proteins that aid in intracellular survival. Protective immunity is conferred by antibodies to lipopolysaccharides and T-cell-mediated macrophage activation. Diagnosis relies on isolation of the organism and serologic tests, with enzyme immunoassay being widely used. Treatment involves tetracyclines, aminoglycosides, or quinolones, though no satisfactory vaccines are available. Recent research has identified promising attenuated purE mutants for vaccine development. Brucellosis has a complex epidemiology, with varying incidence across regions. It is particularly prevalent in the Mediterranean, western Asia, parts of Africa, and Latin America. The disease is primarily transmitted through consumption of contaminated foods and occupational exposure. Human-to-human transmission is rare. Prevention depends on controlling the disease in animals, with some success in eradicating bovine brucellosis in industrialized countries. However, Brucella melitensis remains challenging to control. Molecular genetics of Brucella has advanced significantly, revealing a genome of 2.37 × 10^9 daltons with high homology among species. The genus is classified as monospecific, though the old nomenclature is still used. The genome contains two chromosomes, and various genes are involved in pathogenicity and survival. Antigenic components include lipopolysaccharides, which are the main target of the immune response. Other proteins, such as ribosomal proteins, are also immunologically important. The mechanisms of Brucella pathogenicity involve intracellular survival, evasion of phagocytic responses, and production of inhibitors that prevent phagolysosome fusion. The bacteria can survive within macrophages by synthesizing specific proteins. The role of stress-induced proteins like HtrA and RecA is also being studied. Diagnosis relies on blood culture and serologic tests, with PCR and antigen detection methods under evaluation.