Epidemiology of a toxoplasmosis outbreak in a research institution in northern Parana, Brazil

Toxoplasmosis is a reportable disease in Brazil. The objective of this study was to investigate a toxoplasmosis outbreak at a research institution in Londrina-PR, Brazil. The outbreak was reported in October 2015; however, the first cases occurred in August 2015. Blood samples were collected from 674 persons at the institution. Samples were collected from soil, water (water tank) and food (vegetables) served in the restaurant. Each participant responded to an epidemiological questionnaire. For the blood samples, a chemiluminescent microparticle immunoassay was performed to detect IgM, IgG and specific IgG avidity antibodies; 10.8% (73/674) had evidence of acute toxoplasmosis. Statistical analysis showed a significant association (p < .001) between acute infection and eating lunch in the restaurant of the institution. Regarding the types of food offered in the restaurant during the period, there was a significant association between consuming raw salad (p < .001) and becoming ill. We conclude that the vegetables or raw vegetables served in the restaurant were probably the source of infection; however, the long period between exposure and case reporting made it difficult to identify the source of transmission.