You have probably heard more than once about heartworm disease in dogs, but what is it really about? In this article we tell you about its causes, symptoms, consequences, and what you can do to prevent it.
What is a heartworm, and how is it transmitted?
Canine filariasis, or heartworm, is a serious and potentially fatal heart disease. The causative agent is a blood parasite known as Dirofilaria immitis.
The disease is not spread directly from dog to dog, as transmission requires a mosquito as an intermediary. The mosquito usually bites the dog where the hair coat is thinner. However, having long hair does not prevent the mosquito from biting, since parasites are a world of their own and are transmitted in infinite ways. The spread of the disease therefore coincides with the mosquito season, which can last all year round in many parts of the world.
Once the dog has been infected, the larvae travel through the bloodstream and mature into their adult form, usually settling in the heart chambers and pulmonary vessels.
The female parasite is between 15-36 cm long and 5 mm wide. The male is about half the size of the female. A dog may have up to 300 worms present when diagnosed.
How do I know if my dog has heartworm disease?
It usually takes several years before dogs show clinical signs of infestation. The disease is uncommon in dogs under one year of age because it takes five to seven months for the larvae to mature into adult worms after infection. Consequently, the disease is primarily diagnosed in dogs two to eight years of age.
Unfortunately, by the time clinical signs are observed, heartworm disease is well advanced.
Symptoms of heartworm disease in dogs
- Shortness of breath.
- Fatigue or weakness.
All of these symptoms are most noticeable after exercise, when some dogs may even faint or become disoriented.
Your veterinarian may notice abnormal lung and heart sounds when listening to your dog’s chest. In advanced cases, the abdomen and legs become swollen due to fluid accumulation. There may also be evidence of weight loss and anemia. Severely infected dogs may die suddenly during exercise or excitement.
Heartworm disease in dogs prevention
In order to prevent canine dirofilariasis, it is necessary to avoid the bite of the vector and to eliminate the infected larvae before they become adult worms.
There are some commercial products that help prevent mosquito bites, such as collars or pipettes. These should be used during the warm months, up to and including the last weeks of autumn.
There are also some drugs that help eliminate the larvae from the dog’s organism, which can be administered orally, topically or by injection, according to the veterinarian’s indications.
Preventive treatment should be carried out after verifying, through the application of a test, that the dog does not suffer from the disease.