horse-with-bridleA recent cluster of equine infectious anemia (EIA) cases in Saskatchewan highlights the personal side of EIA control. EIA is a serious insect-borne viral disease of horses that can cause illness ranging from mild to fatal. Some horses recover uneventfully but are then potential sources of the virus for others, and disease can build up slowly and silently in the horse population. Because the disease can be so severe and survivors become life-long carriers, there are EIA control programs (and importation rules) in many countries, including Canada. Here, horses that test positive for the virus must be euthanized, or housed in strict fly-proof isolation that is utterly impractical in most cases. So, a positive test almost always means euthanasia, even if the horse appears outwardly healthy. Some horses are diagnosed when they get sick, and others are identified during routine testing (many people still refer to this as the “Coggins test”, but the test used for initial testing is now different).

A recent cluster of EIA infections was detected on a farm in Saskatchewan. In July, one horse on the farm was identified as being infected. This lead to an investigation, because EIA is a federally reportable disease.  Ultimately 9 other positive horses were euthanized on Aug 19. It was suspected that more euthanasias would follow,  because more test results were pending.

While there is some (rather token) compensation for animals that must be euthanized due to EIA infection, the owner’s comments are similar to those from other outbreaks:

“Some of these horses, I’ve got a lot of money invested in them, and some of them maybe aren’t worth much to people,” he said. “But to ourselves, they’re worth a lot of money because they’re trustworthy. They’ve done us very well. How do you put a price tag on that?”

 “(The horse) can act normal, be normal, do normal everyday things,”[the rancher] said. “You can ride them and everything like that, but until you draw blood from them you’ll never know (they’re infected).”

The financial and emotional impact of euthanasia of positive horses can be substantial. This can lead to arguments both for control (e.g. let’s control the disease so this doesn’t happen again) and against control (e.g. let’s stop killing horses that aren’t necessarily sick).

EIA control is a timely topic in Canada, given potential changes coming to the national control program. One concern is whether the program is effective or if it mainly just satisfies international horse movement concerns.

Reasons for having a control program:

  • EIA is a nasty disease that can spread silently in the horse population.
  • Testing is a key part of control and measures to deal with positive animals (unfortunate as they are) are critical to containing or eliminating the disease
  • Control of EIA is important for international horse movement, as increased barriers could be put in place if this disease is not considered adequately controlled within Canada.

Reasons against having a control program:

  • It’s expensive
  • Testing is unbalanced. Some horses (e.g. competition horses) are tested regularly while others are almost never tested. The horses that are regularly tested are typically the low risk horses, while the ones at highest risk of infection are not tested.
  • The implications of a positive test can lead people to avoid testing unless it’s absolutely required.
  • There are questions about why the government should pay for this program, since it’s not a disease that affects people or food animals.

In the outbreak reported above, the owner said:

“I think (the government) should start implementing it, and make it a mandatory test right across the board. I think that’s the only way you’re ever going to get a little bit of control on this disease, otherwise it’s going to run rampant.”

You’ll find lots of other people in that area that will say “I think the government should stay away. They’re wasting a lot of our money and killing our horses, even the ones that aren’t sick.” (I’m making up that quote but it’s pretty much verbatim from conversations I’ve had.)  Not a good way to contain a disease, but you can see why comments like that are made.

There are a lot of knee-jerk reactions to discussions of EIA control, but once you get thinking about the issues, it becomes very hazy. Good arguments can be made for many different options, including keeping the program as it is, or modifying the program to reflect the fact that EIA is well controlled in some regions but poorly controlled in others. Ultimately, the equine industry will have to take a leading role in determining what is required from an EIA program in Canada, the implications of any changes, and how to sustain any funding for the program since federal efforts may not be maintained at the current level in the future.

There will be a lot more debate, only some of which will be based on science.  It will be interesting to see where this ends.

An infosheet (short and long version) on equine infectious anemia is available on the Worms & Germs Resources – Horses page.