It is unfortunate when people use half truths and selective information to propagate their negative positions and to misinform others. The history of CWD as presented is not complete nor entirely correct. The “discovery” of this disease occurred in 1967 in a wildlife research center in Colorado, not on a game farm. It took several years to identify what was killing the deer and elk held in the facility for experimental purposes, and during those years many animals came and went before it was determined what the cause was. Animals were released back to the wild, transferred into private hands and to zoos. In 1974 the Toronto zoo had a positive case of CWD in a mule deer traced back to the Colorado facility. It has never been determined if the disease was generated on site or came in with captured animals. Prior to this time the technology to identify and diagnose the disease did not exist.
CWD is found only when it is looked for. One cannot say an area is free of CWD if no one is looking for it. While there is widespread and thorough monitoring of farmed and ranched elk and deer, there is relatively little monitoring of wild animals. Maps of CWD in wildlife may show the presence of the disease in a location, but rarely show rates of infection in that area. Many areas do not submit hunted animals for analysis, so it is unknown if the disease is present.
In Western Canada, most of the deer and elk raised domestically are professionally tested for CWD after their death. The initial diagnosed case in Saskatchewan was determined to have come with animals imported from United States. The US source ranch had received animals from the wildlife research facility mentioned above. Subsequently several positives have traced back to this initial infection. Those herds were entirely depopulated. For a short period of time, there was no CWD detected on domestic farms and it was thought to be gone. However, the disease then reappeared, but analyses of the source have generally ruled out farm to farm transmission and suggest infection from the wild as the most probable cause.
Not all CWD is linked to previous cases. Several cases diagnosed on ranches in North East Saskatchewan were never linked by Canadian Food Inspection Agency to the original Saskatchewan case. Furthermore, recent cases in Europe – Finland in particular – were found to involve different strains than North American ones. CWD also exists in 9 US states in the free-ranging herds, but has not been detected in game farms or game farms are not allowed in those states. This suggests that CWD may start spontaneously, or it has previously existed and was not detected.
CWD has not been shown to transfer to humans to date. Presentations by Dr. Stephanie Czub of CFIA suggest that monkeys exposed to CWD material will develop the disease over time. However, despite numerous presentations and public appearances by Dr. Czub, this material has not been subjected to scientific peer review, nor has it been published in an accredited scientific journal. Thus far, the conclusions are opinion only. Furthermore, a similar study conducted by the National Institute of Health in the US found several contradictions to Czub’s conclusions. In that study, several monkeys developed neurological symptoms but never developed the disease. Secondly the lesions in question in the monkeys were found in other areas of the brain than where CWD is known to infect and thirdly, the control animals had the same lesions as the infected ones. The NIH has also monitored areas of the US where CWD is known to have existed for 50 years and has so far not found any increases in neurological diseases in humans.
It is very unlikely that you will ever see a wild animal with CWD and only a low percentage of any population will die of it in the wild. Studies from Wyoming Fish and Wildlife show causes of death of infected animals are firstly predators, then road kill, hunting and fourthly CWD. Colorado has had infected populations for over 50 years yet recently recorded the highest population numbers and hunter kills of elk ever in over 100 years of monitoring.
A new undertaking by the Saskatchewan Cervid Alliance will be implementing live testing for detection of CWD. Technology is now available for industry to begin this. We also promote co-operation with wildlife to jointly work on this issue.
Domestic elk and deer producers work hard to ensure the health and security of our products and we expect the same effort from stakeholders outside of the fence. Our removal will not change what is happening in wildlife. You cannot stop the sun from shining nor the wind from blowing and you most certainly will not stop wildlife from migrating. We as an industry did not create this problem, but we are committed stakeholders in its solution.
Harvey Petracek,
Director, Canadian Cervid Alliance
Saskatoon, Saskatchewan