During February through April 2018, routine surveillance by the Minnesota Department of Health identified 3 toxoplasmosis cases with the same last name. All three cases were part of an extended family who hunted deer together and stayed at a family cabin between November 3-7, 2017. Fourteen of 15 people who were at the cabin agreed to be interviewed. Eleven provided serum for testing. Four of the 14 interviewed met the case definition, including 3 confirmed cases and 1 probable case. Dates of illness onset sere November 17 and 18. One person was hospitalized for 5 days. No one died.

Four of 10 people who field dressed deer met the case definition versus zero of four persons who did not field dress deer. Four of nine persons who consumed venison became ill, compared to none of the 5 five persons who did not consume venison. Four of the 7 persons exposed to potentially raw or undercook venison acquired toxoplasmosis, compared to none of the 7 person who did not report eating raw or undercooked venison.

Serum from the four cases were positive for Toxoplasma infection. Testing showed that 2 of the 4 cases were likely exposed within the timeframe of November 3-5, 2017. The other two cases' serology estimated that they could have been exposed to Toxoplasma greater than 1 year prior to serum collection dates. One case was diagnosed by an ophthalmologist and started on anti-Toxoplasma medication 4 months prior to serum collection which may have influenced results.

Family members reported that approximately 4 deer were killed. Venison was processed and the fresh inside loins and back strap of one of two deer were fried and consumed on November 5. Five families provided packages of venison for testing. One package of steaks was positive for Toxoplasma.