Recently researchers at the Canadian Food Inspection Agency announced that their experiments with Chronic Wasting Disease (CWD) on macaques were yielding some alarming results. Of the 18 macaques that they exposed to CWD, 5 have been confirmed as infected. Of the 5 infected macaques, two were exposed to CWD by direct introduction to the brain, one was administered infected brain material orally and two were fed infected meat.
CWD (Chronic Wasting Disease) is an incurable prion disease that causes fatal degeneration of the brain in deer. Until this point, there had been no evidence that CWD could jump to humans, but the concern has been present since CWD was first documented in the late 1960s, because CWD’s sister disease – bovine spongiform encephalopathy (AKA “Mad Cow Disease”) has killed 229 people in the UK.
The implications of this discovery have immense potential. If CWD can indeed jump to humans, hunters are concerned about the spreading potential of the disease. Since cases of CWD have been reported in 24 states, and there currently are few if any regulations in place for preventing the spread of CWD, the risk of spread is quite high. Hunters postulate that the best option to protect humans against CWD is to test all deer meat for CWD before consumption.
In my opinion, the current results of this research are intriguing and have the potential to be alarming, but are not yet conclusive enough to set off national alarm bells. The experiment size is quite small, having only 18 participating macaques. Of those 18, only 5 have been proven to be infected, after a variety of different treatments. These results are not conclusive enough for us to be certain that humans are in danger of being infected with CWD. While the results do prove that it is possible for macaques to be infected, the infection methods for most infected macaques are so drastic that they do not correspond to likely real-life scenarios. For alarm bells to actually start ringing, I believe far more experiments need to be done to show realistic susceptibility in macaques and other primates. Additionally, there should be some documentation of the possibility of infection in humans. Because it is unrealistic and unethical to do similar experiments as have been previously performed on macaques on humans, the similarities in disease susceptibility between macaques and humans would have to be proven.
Overall, while these findings are very interesting and certainly cause for conversation, I don’t think we should be preparing for Mad Cow Part Two just yet. Hopefully more research in the coming years will make the possibilities less murky.