For more please visit: www.DogExplorer.com – comments are moderated! Follow us on Twitter http – Every month, lots of dog owners, and a few cat owners, give their pets some form of heartworm prevention. But recent studies are showing increasing numbers of heartworm positive pets across the country. Some people believe the worms now have the upper hand. Has our trusted protection failed us? Dog owners, and a growing number of cat owners understand that once-a-month heartworm preventives keep their pets safe from a very serious cardiovascular parasitic disease. Despite consistent use of preventive medications, a significant number of dogs are testing positive for heartworms, especially in the mosquito heavy Southeastern US. Are we seeing the beginnings of a resistance movement? In some cases, careful questioning of clients reveals some monthly doses of medication were not given, opening the door for potential infection. In other cases, medical records and client compliance appear to be complete, yet the pet is positive on the annual heartworm blood test. Heartworm preventive works by killing immature heartworm larvae that are spread by mosquitoes. In theory, a pet who receives medication each month should be protected and never have a positive heartworm test. Why then, do some dogs test positive? Many owners are quick to blame the heartworm preventives. They believe continued use of the drugs will create resistant worms and that will lead to an increase in positive cases …