Keeping the dog on HW prevention is in our adoption contract -- and their history of doing so is part of our pre-adoption vet reference check. We talk about it during adoption.
Aside from the cost of HW treatment, we also discuss how hard it is on the dog, and the fact that we've known several dogs who died during treatment, despite the vet doing everything right. The fact that the dog has to survive three very expensive injections of an arsenic-based compound during treatment tends to sober people. I also describe what it looks like when a dog goes Caval in end-stage HW disease -- it's a God-awful way for a dog to die.
Even in the high-HW regions of the South, there is an economically disadvantaged population that thinks that "worms" are only "intestinal" worms, and doesn't understand that heartworms are not treated by giving the dog dewormer. This requires education. This population is likely to adopt through open-adoption shelters (municipal facilities) on low or no-fee weekends. I used to volunteer at one of these facilities and had many such conversations. Once educated, their biggest barrier is cost -- regular vet exam fees, heartworm test fees, vet clinic product mark-up. They love their pets but don't have the money to go to a "regular" vet. In some cases, even having a vehicle to take the dog to the annual exam is a challenge. They are more likely to buy HW meds directly from the shelter than from a community vet, and would be likely to be interested in generic ivermectin tablets that are very low cost (e.g., Iverhart, TriHeart Plus, etc.), esp. if offered by the shelter at the time of adoption. I used to write down the names of the cheapest local "discount" vet clinics, the stores with low-cost pop-up vax weekends, and the websites where they could buy very cheap prevention -- having a handout would make a lot of sense!
I've long thought that shelters serving economically challenged populations should get grants to wrap a year's supply of HW prevention into the the adoption -- and offer community vetting clinics for alumni if at all possible to help people access HW tests, vax boosters, and very low-cost prevention. Low-cost annual clinics are essential for preserving access since HW meds are not OTC.
In Northern areas, there is an opposite problem of affluent holistic-favoring adopters who are likely to adopt from breed rescues or shelters that do transports of dogs "with a story." They're afraid of "putting poisons in the dog" with products from "big Pharma." They need education on how much worse the arsenic-based HW treatment is as a "poison" than the low-dose preventions, as there is no viable holisitic HW prevention at this time.
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Maggie Thomas
President
Red Stick German Shepherd Rescue
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