Toxoplasmosis Outbreak Associated With Toxoplasma gondii-Contaminated Venison-High Attack Rate, Unusual Clinical Presentation, and Atypical Genotype.

Background: During 2017, in response to a physician's report, the Wisconsin Department of Health Services, Division of Public Health, began investigating an outbreak of febrile illness among attendees of a retreat where never frozen, intentionally undercooked, locally harvested venison was served. Preliminary testing tentatively identified the illness as toxoplasmosis.

Methods: Confirmatory human serology panels and testing of the venison to confirm and categorize the presence and type of Toxoplasma gondii were completed by French and American national reference laboratories.