By Veterinary Practice News Editors The American Heartworm Society (AHS) has announced a new set of veterinary best practices for minimizing heartworm transmission in dogs relocated due to recent natural disasters, a cross-country family move, or other circumstances. The guidelines include recommendations for heartworm testing, treatment, and prevention, and were developed in collaboration with the Association of Shelter Veterinarians (ASV). “Preventing transmission of D. immitis has always been a focus of the AHS Heartworm Guidelines,” sais Chris Rehm, DVM, AHS president. “However, we believe we need to do more, given the potential for heartworm-positive dogs to serve as reservoirs for infection. For example, if a microfilaria-positive dog is rescued in one state and subsequently moved to a new home in another state where nearby pets are unprotected, mosquitoes feeding on the new dog can quickly become heartworm vectors. The results can be disastrous for unprotected pets in the vicinity.” Measures can be taken to protect the health of both infected animals and their new neighbors, according to Dr. Rehm. While the ideal scenario is to treat infected dogs before transporting or traveling with them, situations often dictate that infected animals cannot undergo a full course of heartworm treatment, including adulticide administration, before hitting the road, he said. The AHS’ Transportation Guidelines are designed to prevent infected dogs from becoming heartworm reservoirs, to ensure that untimely travel does not trigger heartworm disease complications, and to assure that, once treated, dogs are on lifelong heartworm prevention. The new best practices include the following steps: Testing of all dogs six months of age or older prior to relocation; Relocation delay for heartworm-positive dogs; Pretreatment (g., administration of macrocyclic lactone drugs, application of an EPA-approved product that kills and repels mosquitoes, and antibiotics) for heartworm-positive dogs when relocation cannot be delayed to allow for the full series of treatment Guidelines for microfilaria testing and retesting to avoid the transport of microfilaremic dogs Guidelines for transport following administration of melarsomine to infected dogs “It is clear that care, cooperation, and communication are needed on both ends of any journey that involves a heartworm-positive dog,” said Rehm. “Our goal is to help veterinarians who oversee the health of both traveling and adopted dogs—as well as their clients—understand the threat and make the prevention of heartworm transmission a priority.
