Creutzfeldt-Jakob disease in unusually young patients who consumed venison

Background: Creutzfeldt-Jakob disease (CJD) in humans and chronic wasting d isease (CWD) in deer and elk occur in the United States. Recent reports of 3 unusually young patients with CJD who regularly consumed deer or elk meat created concern about the possible zoonotic transmission of CWD. Objective: To examine the possible transmission of CWD to humans. Patients: Three unusually young patients (aged 28, 28, and 30 years) with C JD in the United States during 1997-2000. Methods: We reviewed medical records and interviewed family members and sta te wildlife and agriculture officials. Brain tissue samples were tested usi ng histopathologic, immunohistochemical, immunoblot, or prion protein gene analyses. Main Outcome Measures: Presence or absence of established CJD risk factors, deer and elk hunting in CWD- endemic areas, and comparison of the evidence for the 3 patients with that of a zoonotic link between new variant CJD an d bovine spongiform encephalopathy. Results: None of the patients had established CJD risk factors or a history of travel to Europe. Two patients hunted game animals and 1 was a daughter of a hunter. Unlike patients with new variant CJD, the 3 patients did not have a unique neuropathologic manifestation, clinicopathologic homogeneity, uniformity in the codon 129 of the prion protein gene, or prion characteri stics different from those of classic variants. Conclusions: Although the occurrence of 3 unusually young patients with CJD who consumed venison suggested a possible relationship with CWD, our follo w-up investigation found no strong evidence for a causal link. Ongoing CJD surveillance remains important for continuing to assess the risk, if any, o f CWD transmission to humans.