MILWAUKEE _ Production problems at a U.S. manufacturer have delayed chronic wasting disease testing this fall on thousands of deer submitted by hunters in Wisconsin and other states.
The shortage of CWD test kits could not have come at a worse time for the Wisconsin Department of Natural Resources.
A backlog of about 3,600 samples built up during the nine-day gun deer season in November, the state's annual peak of hunting activity and deer harvest, said DNR wildlife director Eric Lobner.
The agency urged hunters to submit deer for testing this fall, a voluntary but critical component of monitoring prevalence and distribution of the fatal deer disease.
And more hunters responded this year. Through Dec. 3, the DNR had received 7,609 samples from hunters, a 24 percent increase from the number received in all of 2016 and the most since 2008, according to state figures.
The lack of test kits caused samples to pile up in the Wisconsin Veterinary Diagnostic Laboratory in Madison.
The DNR issued a statement Monday on social media regarding the delay in testing and urging patience by hunters.
The Michigan Department of Natural Resources made a similar announcement Dec. 1, stating, "This situation is not unique to Michigan; there is a national shortage. The Michigan DNR originally placed its testing kits order earlier this summer."
The supply problems were due in part to increased demand as more states ramped up CWD testing this year. But the manufacturer, Bio-Rad Laboratories Inc. of Hercules, Calif., also had internal production issues, according to laboratory managers in several states.
Chronic wasting disease is a transmissible spongiform encephalopathy, a family of prion diseases that includes Mad Cow and scrapie. CWD is fatal to whitetails and other members of the deer family but has not been shown to cause illness in humans.
However, state and federal health officials recommend humans avoid consuming meat from CWD-positive animals.
In line with this recommendation, thousands of Wisconsin hunters are likely holding venison in freezers and awaiting test results before eating the meat.
Before the test kit shortage, turnaround time was about eight days in Wisconsin for CWD results from the ELISA test manufactured by Bio-Rad. The time includes sample shipping, preparation, testing and reporting.
Over the last month, results have not been available for more than 20 days.
The logjam is about to break, however. On Friday, Wisconsin received enough test kits to process more than 7,000 samples, said Ben Johnson, WVDL staff microbiologist.
If a positive test result is found on a deer from outside the CWD-endemic area, a follow-up immunohistochemistry test is performed. In such a case, the results could be further delayed by seven to 14 days.
"We greatly appreciate the patience of hunters who are waiting to find out the results," Lobner said. "Together with the staff at WVDL, we are doing everything possible to process the remaining samples in the coming days."
The DNR is providing test results to hunters by email (if the address was provided to the agency) and by mail. Hunters also can check the DNR website, where results are being updated daily.
