Prevalence of brucellosis and risk factors associated with its transmission to slaughterhouse employees in the Cuiaba metropolitan area in the state of Mato Grosso

Abstract

The aim of this study was to investigate the prevalence of Brucella abortus infection in employees of two slaughterhouses (A and B) in the metropolitan area of Cuiaba in the state of Mato Grosso and the risk factors associated with its transmission. We collected 134 blood samples from workers in all sections of the slaughterhouses to evaluate brucellosis, and we administered a questionnaire to obtain information about potential risk factors associated with its transmission. We also collected blood from 468 cows during slaughter on the same day of the blood collection from the slaughterhouse workers to determine bovine seropositivity. Six (4.5%) out of the 134 workers examined were positive for B. abortus infection, and all worked as slaughterers. We found a significant association between the prevalence of brucellosis and slaughterers compared to other occupations at the slaughterhouse. It is noteworthy that four seropositive workers had worked as a slaughterer in other establishments, they did not use personal protective equipment (PPE) and they had consumed dairy products without heat treatment. In assessing the prevalence of brucellosis in slaughtered animals in both slaughterhouses, there was a higher number of seropositive cows at slaughterhouse B than slaughterhouse A: of the 468 cows tested in both slaughterhouses, 35 (7.5%) were positive for B. abortus infection, as determined by the 2-mercaptoethanol test (2-ME). Slaughterhouse workers are susceptible to infection by B. abortus, and it was noted that in both slaughterhouses, all of the seropositive workers were slaughterers. Cows that were positive for B. abortus were slaughtered in both slaughterhouses without proper sanitary procedures and necessary information for slaughter. Not using personal protective equipment and the slaughter of animals that are seropositive for brucellosis are risk factors for the transmission of the disease to slaughterhouse workers.