Heartworm

Heartworm begins from a mosquito bite, but for dogs and cats the results can be fatal. The minute baby heartworms grow and fill the blood vessels leading from the heart to the lungs weakening the heart and filling the lungs with fluid. The adult worms can be up to 30 cm long. Like most vets, I have a heart in a jar on my shelf that is absolutely full of heartworms. It is easy to see why so many worms can cause problems, but even just one worm can be a concern. Treating dogs and cats with heartworm can be risky and expensive but prevention, whilst lifelong, is straightforward.

Heartworm, like so many diseases, is most at home in the tropics where there is an over abundance of mozzies. In recent years however, due to increased travelling by dogs the disease has spread across the country. Certainly in all areas of the Territory prevention is not optional but vital.

Heartworms primarily affect dogs although there is increasing evidence that it is a growing problem in cats. One of the reasons we may have missed it for so long in cats is that the first sign in cats is sudden death and generally people have buried them rather than looked for a cause. Prevention in cats is with tablets or spot on behind the shoulders.

In dogs we now have a variety of choices to prevent heartworm with. There are three groups; dailies, monthlies and a year long injection. Most people cannot manage the dailies as sooner or later they forget to give them; the monthlies are the most popular and come in variety of forms – tablets, meat chews, spot ons, and injections. Some of the monthlies will do other worms as well. The year long injection is very popular because you don’t need to remember anything, simply wait for the reminder in the mail from your vet to remind you its time for your dog to visit.