Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy (TSE) of deer and elk. To date, this disease has been found only in cervids (members of the deer family) in North America. First recognized as a clinical "wasting" syndrome in 1967 in mule deer in a wildlife research facility in northern Colorado, it was identified as a TSE in 1978. CWD is typified by chronic weight loss leading to death. The disease is also known as 'zombie deer disease', because infected deer behave strangely, and like a zombie. It is highly likely the disease is spreading to humans. CDC studies proved it could, albeit at a low rate (1 million times less efficient). However, as long as a conversion happens, it is still possible to transmit to humans.