HEARTWORMS

Heartworm

Symptoms

Heartworm disease is caused by parasitic worms that live in the heart, lungs, and blood vessels of affected dogs. Symptoms can range from mild to severe, depending on the number of worms present and how long the dog has been infected. Common symptoms include:

  • Coughing: Dogs with heartworm disease often develop a persistent cough, which may worsen with exercise.
  • Fatigue or lethargy: Infected dogs may tire easily, even after mild physical activity.
  • Difficulty breathing: Severe cases may cause labored breathing, rapid breathing, or wheezing.
  • Weight loss: Chronic infection can lead to gradual weight loss, even in dogs with a normal appetite.
  • Swollen abdomen: Fluid buildup in the abdomen can occur in more severe cases, making the dog appear bloated.
  • Collapse or fainting: In the worst cases, heartworm disease can lead to sudden collapse or fainting, especially during exercise.

Transmission

Heartworm disease is transmitted through mosquito bites. When a mosquito bites an infected dog, it picks up tiny heartworm larvae (microfilariae). These larvae mature inside the mosquito and are transmitted to a new host when the mosquito bites another dog.

  • Mosquitoes are the only vector: Heartworm larvae cannot be passed from dog to dog directly; it always requires a mosquito to transmit the parasite.
  • Geographical risk: Areas with warm, humid climates are more likely to have mosquitoes and, therefore, a higher risk of heartworm disease. However, heartworms have been found in all 50 U.S. states, so year-round prevention is recommended.

Diagnosis

Heartworm disease is diagnosed through a combination of clinical signs, blood tests, and possibly imaging:

  • Blood test: The most common diagnostic tool is the heartworm antigen test, which detects proteins produced by female heartworms.
  • Microfilaria test: A blood sample may also be examined under a microscope to detect the presence of heartworm larvae in the bloodstream.
  • X-rays or ultrasound: In severe cases, imaging can help assess damage to the heart and lungs or detect the presence of adult worms.
  • Physical examination: Veterinarians may also look for symptoms like coughing, fluid in the abdomen, or abnormal heart sounds during a physical exam.

Treatment

Heartworm treatment can be complex and should be handled by a veterinarian. The process typically involves:

  1. Stabilization: If your dog has severe symptoms (such as difficulty breathing or an enlarged abdomen), your vet may need to stabilize them before starting treatment.
  2. Adulticide treatment: The most common treatment for adult heartworms is an injection of melarsomine, which kills the adult worms in the heart and lungs. This treatment is administered in a series of injections over a few months.
  3. Microfilariae treatment: After adult worms are eliminated, your vet may treat the microfilariae (baby worms) to ensure they do not mature into adult worms.
  4. Strict exercise restrictions: During treatment, dogs must remain as calm and inactive as possible. Activity can cause the dead worms to break apart and block blood vessels, which could lead to serious complications.
  5. Post-treatment care: After treatment, your dog will need regular check-ups to monitor for any complications, including infection or damage to the heart or lungs.

It is important to note that treatment can be expensive and sometimes risky, especially for dogs with advanced heartworm disease. Prevention is far safer and more effective.

Prevention

Preventing heartworm disease is far easier and more cost-effective than treating it. There are several options available to protect your dog:

  • Monthly preventatives: The most common form of prevention is oral or topical medications given once a month. These medications, such as Heartgard®, Interceptor®, Sentinel®, and Revolution®, kill any larvae before they can develop into adult heartworms.
  • Annual injections: For dogs that struggle with monthly doses, there is a ProHeart® injection that provides heartworm prevention for up to 12 months.
  • Year-round prevention: In areas with a high mosquito population, it is crucial to give heartworm preventatives year-round, even during the colder months when mosquitoes are less active.
  • Routine testing: Even on preventatives, it's important to have your dog tested for heartworms annually to ensure they are protected.

Key Points to Remember

  • Heartworm disease is a serious, often fatal condition that can cause permanent damage to the heart, lungs, and blood vessels if left untreated.
  • The disease is transmitted by mosquitoes and cannot be passed directly between dogs.
  • Early detection is key to minimizing damage, and preventing heartworm disease is easier than treating it.
  • Be sure to maintain a consistent prevention schedule to protect your dog, especially in areas where mosquitoes are prevalent.

Where to Find Preventatives

For reliable heartworm prevention products, visit the Shopping List section on my website for trusted products and links to order online. Taking proactive steps now can help keep your dog safe and healthy for years to come!