Colorado Division of Wildlife: Hunter Harvested Moose Tests Positive for CWD

From the Colorado Division of Wildlife

9/29/2005
Division of Wildlife

Hunter Harvested Moose Tests Positive for CWD

The Colorado Division of Wildlife (DOW) has confirmed that a bull moose killed by an archer has tested positive for chronic wasting disease (CWD)....

This is the first time that a moose has tested positive for CWD in a natural setting. Kreeger et al. reported experimental infection of moose with CWD (through oral inoculation) at the 2nd International CWD Symposium (abstract on page 54 of the symposium program).

The significance and epidemiology of this finding is unknown. Perhaps the moose could have been infected through consumption of infected faecal matter, either from elk, mule deer, or perhaps another moose. Elk and mule deer have CWD in this region (0.43% [n = 701] of elk and 1.3% [n = 235] of mule deer tested in the data analysis unit where the moose was shot were CWD positive in the 2002/3 and 2003/4 hunting seasons; data from here).

It isn't known if this moose was exhibiting clinical signs, and in Kreeger's experiment the moose all died of other causes than CWD. However, one moose did exhibit spongiform changes in the brain, suggesting that CWD might cause disease in moose.

In the past, moose have not generally been tested for CWD. I suspect that wildlife agencies will start to incorporate moose into their fall sampling activities.

We are clearly very early in our understanding of CWD epidemiology.