CWD

[P6smSKC]

These questions were originally for C. Killmaster however, if anyone else has an opinion on the matter feel free to speak up.

With CWD established in Tennessee, and the length of time it takes for a deer to show symptoms once contracting it, is it possible CWD is already here in GA now?

I have read it takes up to a year, sometimes two years, from the time a deer contracts the prions to the time the deer shows the tell tale symptoms (drooping head/neck, emaciated look, drooling etc.) Not only this, but in order for us to notice CWD here in GA to officially report it, we would have to have a hunter check one in with CWD and it be specifically tested or have someone notice an animal acting odd and report it to DNR and then the DNR get a hold of the animal to test it. Seems to me by the time we notice CWD here in GA it would have already been circulating, at least in low numbers, for a while.. perhaps up to a year or two. This has lead me to decide to not eat venison this year and wrestle with the idea of maybe being done deer hunting altogether (which is very hard for me to accept) because I would worry once it has been found here, that I could have eaten one that may have already had it.

Could this be possible or am I missing out on some great sausage and Jerky this year? Am I being too careful or is this a reasonable concern?

The CDC states it is unknown whether it can be transmitted to humans or not yet, but to not knowingly eat a CWD positive deer. They say to specifically avoid spinal cord tissue and brain tissue from the animals. But there have been studies where Monkeys (can’t remember the type but they were genetically very similar to humans) were fed CWD positive venison (I think cooked and uncooked) and they DID contract CWD. On top of this we do know eating beef with BSE (Mad Cow)results in contracting it in the human form (CJD).

Anyway, wanted to get your opinion on this. Hunting with my dad is just something I have done since I was a kid and something I look forward to every year. Plus I make some great smoked jerky and I always look forward to the fresh tenderloins on the grill the day after a kill.

I also wonder what will happen once it is widespread here. I have a garden and the prions have been reported to be absorbed from the soil into plants, which is a vector for transmission in the wild deer population. Makes me wonder if the deer running through the neighborhood could contaminate my garden veggies, or produce we get at the store for that matter. A lot of what we get from the stores comes from farms with plenty of deer running around, some in areas already known to have CWD established in the area.

Thoughts?

 

[C.Killmaster]

Great questions!

CWD does have a long incubation period, ~18 months so it would be a long time before the first deer showed up with symptoms. While hunters reporting sick deer to DNR is a big part of disease surveillance, we also test a lot of otherwise healthy hunter killed deer. Most of those samples we collect each fall at deer processors around the state. We've been testing deer for CWD in Georgia annually since 2002.

Is it possible that it's here and we just haven't found it yet? Yes, and that is true for every state that hasn't had a positive case. However, not having much of a captive deer industry in Georgia knocks out the single biggest risk factor for CWD. Tennessee discovered CWD after working with Cornell University to develop a surveillance strategy that would direct sampling effort to the most likely areas of the state to look. The next year we contracted with Cornell to do the same for Georgia.

 

[C.Killmaster]

The CDC states it is unknown whether it can be transmitted to humans or not yet, but to not knowingly eat a CWD positive deer. They say to specifically avoid spinal cord tissue and brain tissue from the animals. But there have been studies where Monkeys (can’t remember the type but they were genetically very similar to humans) were fed CWD positive venison (I think cooked and uncooked) and they DID contract CWD. On top of this we do know eating beef with BSE (Mad Cow)results in contracting it in the human form (CJD).

There was a study on macaque monkeys a couple of years ago in Canada that suggested that they could be susceptible. The authors failed to get the study through peer review, so there must have been some serious flaws in their research. An identical study was conducted in the US that found the opposite and the monkeys did not get sick. Here is a link to that study.

https://journals.asm.org/doi/abs/10.1128/JVI.00550-18

Looking at all the research using monkeys and humanized mice, there does appear to be a strong species barrier that prevents human infection from eating infected venison. They will likely never be able to completely rule it out though.

 

[C.Killmaster]

I also wonder what will happen once it is widespread here. I have a garden and the prions have been reported to be absorbed from the soil into plants, which is a vector for transmission in the wild deer population. Makes me wonder if the deer running through the neighborhood could contaminate my garden veggies, or produce we get at the store for that matter. A lot of what we get from the stores comes from farms with plenty of deer running around, some in areas already known to have CWD established in the area.

Let's say hypothetically you live in an area endemic with CWD, here's what it likely will be like.

You will have to test every deer you kill for CWD before you eat it and you will have to throw out any that test positive. Managing for mature bucks will be difficult. You likely won't be allowed to bring whole carcasses out of the area, just boned out meat and hides/antlers. Baiting and feeding will likely be prohibited.

While prions do remain infectious in the soil and can be taken up by plants, those are not likely to be good mechanisms of transmission to other deer or humans (if they ever did discover that humans could be susceptible). Direct contact among live deer seems to be the best mechanism for transmission.

 

[TomC]

I have a sneaking suspicion that baiting might be banned statewide or at least a good portion of central and western KY next year. Already prohibited in the county next to me plus 4 other western KY counties due to confirmed cases found in NW Tennessee.

 

[P6smSKC]

Thank you for the info/your thoughts. Maybe completely stopping deer hunting at the moment is too extreme.

Do we have any options of testing our deer harvested in GA at the moment? If so, how would we go about doing that? I believe they check the brain and some lymph nodes in the neck somewhere?

 

[C.Killmaster]

Thank you for the info/your thoughts. Maybe completely stopping deer hunting at the moment is too extreme.

Do we have any options of testing our deer harvested in GA at the moment? If so, how would we go about doing that? I believe they check the brain and some lymph nodes in the neck somewhere?

Yes, I forgot to mention it. You can call any Game Management office and schedule an appoint to collect a sample. You need to bring the head and preferably a few inches of neck by, but make sure to keep it refrigerated and not frozen. If you don't keep the head cool the sample will be no good. We charge $40 to have your deer tested, we only charge what it costs us.

 

[jiminbogart]

There was a study on macaque monkeys a couple of years ago in Canada that suggested that they could be susceptible. The authors failed to get the study through peer review, so there must have been some serious flaws in their research. An identical study was conducted in the US that found the opposite and the monkeys did not get sick. Here is a link to that study.

So what's the bottom line? Is it safe to feed our monkeys deer meat or not?

 

[C.Killmaster]

So what's the bottom line? Is it safe to feed our monkeys deer meat or not?

Yep, just test the deer first if it came from a known CWD endemic zone. Your monkeys will thank you!

 

[Roadwarrior]

Thank you Killmaster for the information.

 

[JROESEL]

Now what other forum can you have a biologist answer and solve any questions you’ve got in fifteen minutes??? I couldn’t even get that when I was in biology class in college!! Thanks for being such a great example and a walking wealth of knowledge c.killmaster, now to the op, go kill a deer and eat it

 

[lampern]

Does deer urine transmit or spread CWD?

 

[earlthegoat2]

I just hunted in a CWD surveillance area area in MI that has had a confirmed CWD deer in the last year in an adjoining county.

We submitted our heads for testing just as we have done for the last several years there. Every time we asked the biologist there if there had been any positive tests recently and they said there were 1 or 2 statewide in the last 5 years.

Aside From the most recent positive case, that last few that were positive for CWD we’re not even in the surveillance area.

MI has a Bovine TB surveillance area as well and deer are routinely tested statewide for CWD and TB. These tests are what key the DNR in to area where disease may be greater.

I must say though, MI is pretty bush league when it comes to deer reporting. When we submit our heads we give them the location ourselves. There is no other method for the DNR to get a broader idea of what deer are killed where. No online or app reporting system that I am aware of.

 

[earlthegoat2]

IMO, stopping deer hunting is a bad idea. License sales fund CWD testing and surveillance. Without hunting, we would lose the funding and it would be more difficult to figure out when CWD had been reduced since hunters play a big part by turning in deer parts to be tested.

Eliminating artificial baiting and feeding would seem like the best solution to reduce concentrated disease communication events.

Animal rights activists like to say diseases like this are caused, spread, and proliferated by too much animal farming and meat consumption. They then point out many diseases in humans originate in animals. I have to admit, the evidence is compelling but that is for another conversation.

What I really am getting at is CWD and BSE, among others, first noticeably proliferated in domestic cattle. The deer population may have already been affected but either way, an infected cattle population will easily and inevitably effect the local deer herd.

In MI, cattle are also tested for CWD, TB, and BSE aggressively. There have been few instances of thsee disease in the local cattle populations leading one to believe that, at least in MI, CWD and TB are isolated to the deer herd.

 

[C.Killmaster]

IMO, stopping deer hunting is a bad idea. License sales fund CWD testing and surveillance. Without hunting, we would lose the funding and it would be more difficult to figure out when CWD had been reduced since hunters play a big part by turning in deer parts to be tested.

Eliminating artificial baiting and feeding would seem like the best solution to reduce concentrated disease communication events.

Animal rights activists like to say diseases like this are caused, spread, and proliferated by too much animal farming and meat consumption. They then point out many diseases in humans originate in animals. I have to admit, the evidence is compelling but that is for another conversation.

What I really am getting at is CWD and BSE, among others, first noticeably proliferated in domestic cattle. The deer population may have already been affected but either way, an infected cattle population will easily and inevitably effect the local deer herd.

In MI, cattle are also tested for CWD, TB, and BSE aggressively. There have been few instances of thsee disease in the local cattle populations leading one to believe that, at least in MI, CWD and TB are isolated to the deer herd.

CWD isn't really known to transmit to cattle except under expermental conditions where it was directly injected into the brain of cows. TB was transmitted to deer from cattle in MI and it still remains endemic to the deer population, hence the testing.

BSE (mad cow disease) has largely been limited to Europe and was eliminated when they stopped feeding cow bone meal back to cows.

 

[splatek]

@C.Killmaster You mentioned one of the responses to discovering a CWD endemic area would be to eliminate baiting in that area. Is that because there is something about baiting, or bait that puts animals at risk (like feeding bone meal to cattle), or is it simply that bait concentrates deer in an area thus increasing the likelihood of contact spread (similar to the way influenza and the ‘vid spread better indoors because we are in closer proximity to more folks)?
And thanks for the highly informative responses.

 

[C.Killmaster]

@C.Killmaster You mentioned one of the responses to discovering a CWD endemic area would be to eliminate baiting in that area. Is that because there is something about baiting, or bait that puts animals at risk (like feeding bone meal to cattle), or is it simply that bait concentrates deer in an area thus increasing the likelihood of contact spread (similar to the way influenza and the ‘vid spread better indoors because we are in closer proximity to more folks)?
And thanks for the highly informative responses.

It's strictly about not concentrating deer. They banned the use of animal products in feed that could spread prion diseases in 1994.

https://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs144p2_033674.pdf

 

[bany]

Thanks P6 and Charlie for a good read!

 

[Jim Boyd]

Superior information from @C.Killmaster.

We have not been allowed to bait or to bring home the head / any bones from Illinois for well over a decade.

Has not hurt us one bit.

 

[C.Killmaster]

Hopefully this might help with perspective. I pulled these numbers from a study on mad cow disease. To date there has never been a single instance of CWD causing disease in humans, but I'm using this as a hypothetical example.

This is mad cow disease NOT CWD!

Approximately 10 million people are believed to have been exposed to mad cow disease by eating contaminated beef from 1980 to 1996. Of those, they believe approximately 32,000 (0.32% of the population) were genetically susceptible to mad cow. The total number of people that contracted the disease was 232 (0.00232% of the total population, all died from it). While this was obviously a terrible tragedy for those who died, the risk to the individual was very low.