Over the last year, chronic wasting disease (CWD) has been found in one new state, whereas four previously affected states have seen small increases in their CWD-positive regions, reports the Wildlife Management Institute.

Surveillance

In February 2006, the Kansas Department of Wildlife and Parks confirmed that a whitetail doe harvested from deer management Unit 1 in northwestern Kansas tested positive. The addition of Kansas brings the number of CWD positive states to 11. To date, no additional CWD cases have been identified in Kansas.

Despite very extensive surveillance efforts, the Wisconsin Department of Natural Resources has identified CWD from one deer in a new county, Grant, within the state's Herd Reduction Zone.

Similarly, Illinois added Ogle County to its CWD positive counties and saw the border of the affected area in Dekalb County expand 20 miles southward. In response, the Illinois Department of Natural Resources extended its special CWD Antlerless-only Deer Season in January to include all of Dekalb County, along with five other northern Illinois counties already included in the hunt.

The CWD control area in New Mexico has increased from 250 square miles to 400 square miles as a result of recent CWD-positive test results from areas northeast of the original control area near the White Sands Missile Range east of Las Cruces. Interestingly, one CWD positive deer was recently found southeast of San Antonio, 75 miles north of any previously identified cases in New Mexico.

The Wyoming Game and Fish Department identified two deer hunt areas (4 and 11, along the northern half of the Wyoming/South Dakota border) and two elk hunt areas (16 and 22, within the southeast central core of the state) from which CWD-positive animals were taken.

Wyoming tested moose for CWD in 2006, but found no positive animals. Colorado, however, found that two moose harvested southeast of Glendevey in Game Management Unit 7 tested positive for the disease.

CWD Research

In October 2006, newly published research supported what scientists had been suspecting for some time; CWD may be transmissible through the blood and saliva of infected deer. In this study, researchers also tested the transmission of CWD through urine and feces; the results were negative. According to the authors, however, those negative results should be viewed cautiously due to the small number of animals used in the study. These findings provide new insight into how easily CWD may be transmitted through simple social interactions, particularly in situations where animals are found in high densities. Although no evidence to date shows that CWD is transmissible to humans, this study reinforces the need for hunters to use appropriate caution when handling animals harvested in CWD-positive regions. Visit www.cwd-info.org to see recommendations for hunters.

Additional evidence against the transmission of CWD to humans was presented in a September 2006 study that examined whether human deaths from Creutzfeldt-Jakob disease (CJD)?the human equivalent of CWD?in residents living in CWD-positive counties are more frequent than average. By identifying the number of deaths caused by CJD over 22 years in seven Colorado counties that have a high prevalence of CWD in their deer and elk herds, the researchers found that, even though 75 percent of hunting licenses are issued locally and harvested animals generally are consumed locally, there was no significant spike in the prevalence of CJD. In fact, the rate of CJD has decreased over time. While the possibility of CWD transmitting to humans cannot be eliminated, this study reinforces that the risk of its transmission to humans is extremely low, if there is any risk at all. To view this study, go to www.cdc.gov/ncidod/eid/vol12no10/06-0019.htm.