As more veterinarians examine animals rescued from the Gulf Coast region, reports of heartworm disease have become more common in non-endemic areas across the United States and Canada. So common, in fact, that the American Heartworm Society (AHS) released recommendations for the treatment of those animals and AAHA Helping Pets Fund announced a new grant program for the treatment of animals displaced by the hurricanes. Funds are available through The Hurricane Heartworm Treatment Program for heartworm treatments provided only by AAHA-accredited hospitals. Details on the program are available online.

California-based shelter managers and veterinarians were the first to sound the call for help with heartworm cases, said Tom Nelson, DVM, AHS president. In response, the society released a separate set of recommendations for Katrina animals on Sept. 18, 2005. The document is intended to help shelters and private practitioners reduce microfilaria before treating infections. “This is a big issue,” he said. “Dogs coming out of the Gulf Coast at the peak of heartworm season are now all across the country. We want to make [adoption] as safe as possible.”

AHS Katrina recommendations call for a three-dose treatment and a conservative initial approach to reducing the microfilaria. An overzealous approach could cause adverse reactions and anaphylactic shock, Nelson added.

More than half of the abandoned or homeless dogs in the Gulf Region that were sent to other states after Hurricanes Katrina and Rita tested positive for heartworm disease, Nelson said. “We want to prevent the potential [for spread,]” he added.

New AHS Recommendations for Katrina Animals Only

Kate Hurley, DVM, MPVM, shelter medicine program director for UC Davis, stressed the limited use for the new AHS document. “These were created for shelters, and were not intended to replace guidelines for pet animals in any way, nor are they intended to provide shelters with a new standard for heartworm treatment on an ongoing basis,” Hurley said. “They … reflect an attempt to balance the best interest of the animals with the financial constraints of shelters faced with treating dozens or even hundreds of animals.”

The main difference in the Katrina heartworm treatment recommendations and the regular AHS guidelines is an injection of Immiticide, which may increase the cost of treatment by 40 percent but “It is the safer protocol,” Nelson said. It encourages doctors to test for infection before administering preventative medication, which will slowly kill any worms, even those four months or younger that may not show up on tests; and the initial low dose (6 micrograms) of medication will minimize the chance for adverse reactions, Nelson said. “We cannot predict or tell how many worms a dog has,” he added.

To help subsidize the costs of treating heartworm disease, the AAHA Helping Pets Fund launched the Hurricane Heartworm Treatment Program with assistance from the Humane Society of the United States, the American Society for the Prevention of Cruelty to Animals, the Humane Society of Greater Miami and Adopt-A-Pet. Grants of up to $500 are only available to AAHA-accredited practices that provide heartworm treatment to certified animals. Certification is decided by designated shelters participating in animal rescue operations. Detailed guidelines for monies made available through the Hurricane Heartworm Treatment Program are available online.

Industry statistics indicate that only half of the nation’s pets are on heartworm prevention, which illustrates how vulnerable pets are to infection, Nelson said. In addition to the widespread adoption of Gulf Coast dogs, heartworm disease has spread across the United States due to climactic changes, construction, golf courses and a mobile society, Nelson added. Those changes prompted the AHS to recommend year-round prevention for dogs and cats in 2005.