Hookworms and Roundworms | Heartworms | Heartworm Life Cycle

Heartworm disease is a serious condition where parasitic worms live in the heart and major blood vessels of dogs and cats. Heartworm disease can be life threatening, and animals often don’t show symptoms.

How Dogs and Cats Contract Heartworm Disease | Heartworm Disease Treatment | Heartworm Disease Prevention

Heartworm disease: treatment and prevention

How Dogs and Cats Contract Heartworm Disease

• Mosquitoes are the carrier of heartworm disease:
–	Of the 150 species of mosquitoes in the United States, two-fifths may transmit the disease.
–	When a mosquito feeds on an infected dog, it ingests a number of heartworm microfilariae.
–	After developing in the mosquito’s digestive tract, the larvae are spread to a new animal when the mosquito bites again.

• Larvae migrate under the skin for several months, before going into the blood vessels in the lungs.

• Once in the dog’s heart and lungs where they mature and reproduce, releasing more larva into the bloodstream.
–	Adult heartworms can reach one foot in length.
–	Dogs often have 15 to 19 worms living in their heart and lungs.

• In extreme cases, dogs may have up to 250 heartworms at once.
–	Cats usually only carry 1 to 3 heartworms.

• It only takes 1 heartworm to kill a cat.

• Infection can produce the following symptoms:

–

Dogs

•	Fatigue
•	Weight loss
•	Chronic coughing
•	Swelling of the abdomen

–

Cats

•	Asthma
•	Respiratory Distress
•	Vomiting

• Heartworm disease can eventually lead to more serious health problems including lung and heart damage and sudden death.

Heartworm Disease Treatment

• Treatment for dogs takes place in four stages:
–	Test to determine the presence of heartworm disease.
–	Therapy in order to remove adult heartworms.
–	Treatment to remove heartworm larvae.
–	Monthly prevention to avoid future heartworm infection.

• Treatment for dogs can be dangerous as the medicines involved in the treatment are toxic and dogs may need to be hospitalized during the treatment period.

• No treatments are available for cats.

Heartworm Disease Prevention

• Preventive medications are available for both dogs and cats:
–	Approximately 50 percent of dogs and 5 percent of cats are currently on a heartworm preventive.
–	Protecting your pet from heartworm infection is as easy as a visit to your veterinarian, who can provide you with a preventative medication to help keep your dog healthy.

Hookworms and Roundworms | Heartworms | Heartworm Life Cycle