Revista da Sociedade Brasileira de Medicina Tropical 46(6):791-794, Nov-Dec, 2013http://dx.doi.org/10.1590/0037-8682-0160-2013 INTRODUCTION ABSTRACTHuman brucellosis is an occupational disease affecting workers in slaughterhouses, butcher shops and the milk and dairy product industry as well as individuals who work in clinical or research laboratories. We report the fi rst outbreak of a Brucella abortus infection in a Brazilian laboratory and compare the data obtained with reports available in the literature. Exposure was a result of damage to a biological safety cabinet and failure of the unidirectional airfl ow ventilation system. An epidemiological investigation identifi ed 3 seroconverted individuals, 1 of whom had clinical manifestations and laboratory results compatible with infection at the time of exposure (n=11; attack rate=9.1%).