Alzheimer's May Be Contagious

Alzheimer's disease may, in some cases, be contagious, according to surprising results from a new study. "Some of the sporadic Alzheimer's cases may arise from an infectious process" similar to mad cow disease, a researcher says. In the study, mice that were injected with human brain tissue from Alzheimer's sufferers contracted the disease, while mice injected with healthy brain tissue did not.

The new study, however, is preliminary and involves artificial conditions unlikely to occur in the real world. MSNBC notes that researchers are planning experiments to investigate whether Alzheimer's transmission would be possible in a more likely, natural scenario. (More Alzheimer's disease stories.)