Brucellosis reemerged in Bulgaria between 2005 and 2007, marking a return to a disease that had been eradicated since 1958. The resurgence highlights the need for active surveillance and collaboration between public health and veterinary authorities. Bulgaria had previously implemented serologic screening for cattle, sheep, and goats, but after 1998, surveillance focused on high-risk areas near countries with brucellosis. During 2005–2007, 105 human cases were reported, with 84 linked to occupational exposure. The majority of cases were imported, but 54 were autochthonous, indicating local transmission. Animal cases also increased, with 635 confirmed. The outbreak was linked to raw milk consumption and poor hygiene in family farms. The reemergence of brucellosis is not unique to Bulgaria, affecting the Balkans and Caucasus. Factors include increased animal trade, migration, and incomplete public health systems. The study suggests that brucellosis may reappear due to complex disease cycles and changes in social structures. The report emphasizes the importance of health education and active surveillance in controlling infectious diseases. The authors note limitations, including the lack of bacterial cultures and potential over-reporting due to improved surveillance. The study underscores the need for cooperation between public health and veterinary sectors to address public health threats.Brucellosis reemerged in Bulgaria between 2005 and 2007, marking a return to a disease that had been eradicated since 1958. The resurgence highlights the need for active surveillance and collaboration between public health and veterinary authorities. Bulgaria had previously implemented serologic screening for cattle, sheep, and goats, but after 1998, surveillance focused on high-risk areas near countries with brucellosis. During 2005–2007, 105 human cases were reported, with 84 linked to occupational exposure. The majority of cases were imported, but 54 were autochthonous, indicating local transmission. Animal cases also increased, with 635 confirmed. The outbreak was linked to raw milk consumption and poor hygiene in family farms. The reemergence of brucellosis is not unique to Bulgaria, affecting the Balkans and Caucasus. Factors include increased animal trade, migration, and incomplete public health systems. The study suggests that brucellosis may reappear due to complex disease cycles and changes in social structures. The report emphasizes the importance of health education and active surveillance in controlling infectious diseases. The authors note limitations, including the lack of bacterial cultures and potential over-reporting due to improved surveillance. The study underscores the need for cooperation between public health and veterinary sectors to address public health threats.