How to Prevent Heartworm in Your Dog
Heartworms are parasites that live in dogs’ hearts and cause heart failure. Preventing this disease is critical because treatment of adult worms in the heart requires intensive care and can be life threatening.
Mosquitoes transmit larval heartworms from one dog to another by sucking the blood of an infected dog, then regurgitating a little blood when they bite their next victims.
Several excellent products are available for preventing heartworm infection, most of them monthly chew tabs that are so tasty you can just drop them in your dog’s food bowl and he’ll gobble them up. A heartworm preventive can be given to a puppy with his first set of vaccinations.
Before a dog is placed on a heartworm preventive, however, a blood sample must be tested to make sure the dog is not already infected. This simple test can be done in your veterinarian’s office while you wait. A heartworm test isn’t necessary for a puppy under three months of age.
In northern areas, where temperatures reach freezing, dogs need to take a heartworm preventive only during the spring, summer, and fall. In the southern United States, because mosquitoes are present year-round, dogs need to take a heartworm preventive year-round.
Dogs on heartworm preventive should still be tested every year, just in case the medication was forgotten or was ineffective for some reason.