Heartworm is a parasite of the heart. It is transmitted by a mosquito bite. As the mosquito bites the dog, it injects larvae into tissues which are then absorbed into the blood stream. The larvae matures and travels to the heart where the adult worm will live and reproduce. New immature forms (microfilaria) will be released into the blood stream by the adult. When another mosquito bites the dog, this blood will transmit the immature form to other dogs.

If heartworms are not treated they can interfere with the normal flow of the blood in the heart and the vessel serving the lungs , reducing the quality of life of your dog significantly and eventually can cause congestive heart failure and death.

Heartworm is a curable disease, but treatment is risky and expensive. Prevention is very easy. A Heartguard Plus chewable is given once a month, preferably on the same day each month. If given faithfully this is an effective preventative. The makers of Heartguard Plus guarantee its effectiveness as long as it is given to the dog every month and the pet is tested for heartworms yearly.

Heartguard Plus also treats and prevents intestinal parasites such as hookworm and roundworms. It is safe to use in puppies after they are 7 weeks old. This preventative is given all year long in Florida since it is a mosquito endemic area.

Top Spot is a topical insecticide that has some repellant qualities, keeping mosquitoes away, but the use of Heartguard is the safest way to prevent heartworm disease.