CJD isn’t easily contagious from person-to-person contact. The only way to spread it from person to person is through organ or tissue transplants or certain types of hormones taken from a donor who had CJD.
Variant CJD can pass in blood transfusions, but this is extremely rare, and there are only four confirmed instances of this happening. Variant CJD is also extremely rare on its own. As of 2021, there had only been two cases of vCJD in the preceding five years (2016–2021). The last person with a confirmed case died in France in 2019.
Prions can cause similar conditions in different species of animals. BSE affects cattle, scrapie affects sheep and goats, and chronic wasting disease (CWD) affects deer, elk and related species. However, there’s currently no evidence that scrapie or CWD can affect humans.
While there’s no evidence that scrapie or CWD can cause Creutzfeldt-Jakob disease in humans, experts still recommend careful handling of both domestic animals and wild animals hunted for food because of the risk of a mutation that could allow a prion-caused condition to affect humans. Other diseases can also cause illnesses in humans. The U.S. Centers for Disease Control (CDC) and the U.S. Department of Agriculture both have more information about these topics and concerns.