Human infection by Brucella melitensis: an outbreak attributed to contact with infected goats.

Although several outbreaks of Brucella melitensis infection have been reported among laboratory workers or goat cheese consumers, outbreaks related to rural labour have been rarely studied. An outbreak of human brucellosis among farm workers of Argentina was studied and revealed a close relationship with an epidemic of caprine abortions which occurred shortly before on the same farm. High rates of B. melitensis infection were found among goats. Active brucellosis was diagnosed in 33 subjects (14 with positive blood culture for B. melitensis), while other 27 did not show evidence of illness. While 25 of the brucellosis active patients were rural workers, only 5 of the healthy subjects were engaged in rural labour. Active brucellosis was diagnosed in 91.3% of the subjects in continuous contact with goats and in 32% of those having an occasional contact with the animals. All the 60 subjects denied consumption of goat cheese or milk. As shown here, epidemic human infections by B. melitensis may develop among people frequently in contact with infected goat herds or goat manure.