According to the American Heartworm Society (AHS), its "every-three-years survey, which tracks heartworm incidence from data supplied by more than 5,000 veterinary clinics, has documented cases in every state." [Note: this may, and probably does, mean that two or three cases, but not necessarily more, have been reported by these drug-pushing clinics, which represent only a fraction of U.S. veterinarians. The trick is that they don't say where the dogs came from. Colorado received a lot of heartworm-positive dogs after Hurricane Katrina, but the actual rate of heartworm infection in ...