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BCI stories - Heartworms on the island

Before we started going to Big Corn Island, Nicaragua, there was no heartworm disease diagnosed on the island. We were the first group to bring heartworm tests with us, so we really had no idea if they even had them or not, we just suspected it. As we started testing, we were saddened to see so many positives….and so many of them were clinical for it too. We would hear the same story again and again – my dog is losing weight, he has a chronic cough, he seems to struggle when he runs and plays – he doesn’t even run and play any more, etc. And every time, they were heartworm positive. I believe that first year we diagnosed close to 50 dogs with heartworms, and spent a lot of time educating them.

As a quick recap – heartworms are spread by mosquitoes. They infect dogs when a carrier mosquito bites them, sharing the larva, which then slowly grow and migrate to the heart and the adults live there. As you can imagine, worms living in a heart is not ideal – so it leads to heart disease and eventually heart failure if left untreated. Since prior to us it was not even being diagnosed on the island, it certainly wasn’t being treated, and I can’t even imagine how many dogs had likely died from heart failure as it slowly progressed over time.

We scrambled that first year to figure out a treatment plan – here in the states, we do a 3 month regimen of pre-treatment with antibiotics and steroids, then deep intramuscular injections that are repeated a month later, with 2 months of strict rest between and after the treatments. This is obviously not realistic for the island dogs. Luckily there is also what is called the ‘slow-kill’ method where you start them on heartworm preventatives, and antibiotics and steroids, and a dewormer that kills them that is given every 2 weeks for 6 months! It’s a big commitment, but I was so pleasantly surprised by the willingness of every owner who came with their pup and got this terrible news, to keep the medications and follow the dosing instructions.

In follow up years we have also been pleasantly surprised with those who have come back who were previously positive and did all the treatments religiously (even brought back their little vaccine cards with their records!) – and we tested them again and they are negative!! So exciting!! The awareness has increased year to year, and we even had now had people asking for the test and treatment – baby steps towards getting it under control. Every dog treated is one less 😊

There has been some heartbreak with it too – there was this adorable waiter who worked at our hotel and he brought his dog in to be ‘cut’ (aka neutered), and he was coughing so we tested him first. Sure enough, he had heartworms. We explained everything and set him up with all the medications and the plan to have him follow up with the other vet team in 6 months. Two days later we saw him at the hotel and asked about his pup, and with tears in his eyes he told me that he had passed away the night before. He had started having trouble breathing, and then just fainted. My heart sank – I cried about that dog for 2 days. I suspect he had such a heavy worm burden that he had an anaphylactic type reaction with starting the medications – so RARE, so unlikely, but still so heartbreaking. I will never forget as he looked at me with tears in his eyes and said, ‘He was my best friend.’ That will stay with me forever. I know it was not our fault, I know it was still the right choice to treat him, and that is the only dog who we have lost that way…but damn if it doesn’t still sting. He did not blame us at all, and has since gotten another pup (who he has on preventatives!), but that loss was still so hard.

Last year when we went there was also a little old dog owned by our one cab driver, Courtney, who was very clearly in heart failure from heartworms. We tested him to be sure, and had a few general heart medications with us, so started him and explained what was happening to his family as they all cried over the little guy. We all knew he didn’t have much time, and what I was doing was just a band aide, but we hoped that it would at least make him a little more comfortable for the time he had. Once it progresses to heart failure, there isn’t much we can do, except try to control their symptoms until it is time to let them go.

Heartworms are tough – it is impossible to prevent mosquitoes, so we just have to focus on getting dogs on preventatives and treating those we can to cut down on the transmission. Thankfully this is not as a big of a problem here in the states, but it is creeping up here. Every year more and more dogs from states like Virginia, Maryland, and even Pennsylvania, are coming up positive. So my vet advice to you? Consider the preventative – it’s safe and effective, and preventing even one more dog from a terrible fate of heart disease and failure from something we CAN prevent, is worth it every time. Next year – even more tests and more treatments – heartworms – we are coming for you!

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