The aim of the present report was to describe an outbreak of Brucellosis in a family group due to its unfrequency and etiological value. The infection caused by Brucella is a disease of animals (zoonoses) , and humans are accidental hosts. The major determinant of a human risk of acquiring the disease is the contact with infected animals.

The genus Brucella contains four species pathogenic for humans:

B. melitensis, B. abortus, B. suis and B. canis. Brucella are intracellular bacteria and among the species pathogenic for humans, B. melitensis are the most virulent. The organisms commonly enter the body through cuts in the skin of people handing infected animals or through their blood or secretions, and also the entry can include the respiratory or gastrointestinal tracts. Brucellosis exists worldwide, and Argentina reports 300 cases annually. Between August and October 2015, we diagnosed four cases in a family group: these cases are reported in the article.