Outbreak of nephritis by Streptococcus equi subspecies zooepidemicus: case-control study in the municipality of Monte Santo de Minas, Minas Gerais, Brazil, 2013

to investigate an outbreak of nephritis by Streptococcus zooepidemicus in Monte Santo de Minas, Minas Gerais State, Brazil. a case-control study and attempt to isolate the bacterial agent were carried out from January to April 2013, using clinical and laboratory data, interviews and inspections. 417 suspected cases were reported, of which 175 (42.0%) were confirmed; 90.9% lived in that municipality, of which 67.4% were female, with median age of 36 years; 24% of cases were hospitalized; three ice cream shops in the municipality used type A milk; there was significant association between the illness and the consumption of type A milk (odds ratio [OR]=4.16/95%CI: 1.55;11.18), one of the ice cream made with this milk (OR=3.09/95%CI: 1.39;6.86) and milk shake of non-processed milk (OR=3.25/95%CI: 1.13;9.36); the bacterium was not detected in rural properties. the outbreak of nephritis by Streptococcus zooepidemicus was associated with the consumption of milk and dairy products.