Doença do Verme do Coração: O Assassino Silencioso de Cães e Gatos
Vermes do coração são transmitidos por mosquitos e causam danos ao coração e pulmões. A prevenção é simples; o tratamento é perigoso e caro.
Heartworm disease is a serious, potentially fatal condition caused by parasitic worms living in the heart, lungs, and blood vessels of infected pets. It's transmitted by mosquitoes. While dogs are the natural host, cats and ferrets can also be infected. Prevention is simple, safe, and inexpensive. Treatment is dangerous, painful, and costly. RVC provides heartworm testing and prevention. Call +853 6677 6611.
Key Points
- Heartworms are transmitted by mosquitoes — not directly from dog to dog
- Adult worms can grow 12 inches long and live 5-7 years
- Dogs can harbor hundreds of worms; cats typically have only a few
- Symptoms in dogs: cough, fatigue, weight loss, difficulty breathing
- Symptoms in cats: vomiting, coughing, asthma-like attacks, sudden death
- Monthly prevention is highly effective and much safer than treatment
The Heartworm Life Cycle
When a mosquito bites an infected animal, it picks up microscopic heartworm larvae (microfilariae). Inside the mosquito, the larvae develop over 10-14 days. When the infected mosquito bites your pet, the larvae enter through the bite wound. Over 6 months, larvae mature into adult worms that lodge in the heart, lungs, and pulmonary arteries. Adult worms produce new microfilariae, which circulate in the bloodstream and are picked up by mosquitoes, continuing the cycle.
Disease Progression in Dogs
Early stage: no symptoms. Mild stage: occasional cough, fatigue after exercise. Moderate stage: persistent cough, exercise intolerance, weight loss, difficulty breathing. Severe stage: heart failure, fluid accumulation in abdomen, collapse, and death. The number of worms and duration of infection determine severity. Dogs can harbor hundreds of worms. As worms die (naturally or through treatment), they break apart and can cause blockages in pulmonary arteries.
Heartworm in Cats
Cats are not natural hosts for heartworms, so most larvae don't survive to adulthood. However, even immature worms (2-3 inches) can cause severe inflammation in the lungs, called HARD (Heartworm Associated Respiratory Disease). Symptoms mimic asthma: coughing, wheezing, vomiting, and difficulty breathing. Sudden death can occur without warning. There is NO approved treatment for heartworm in cats — prevention is the only protection.
Treatment vs Prevention
Prevention: monthly chewable or topical medication kills larvae before they mature. Cost: $50-150/year. Safe and easy. Treatment for dogs: strict cage rest for months, deep IM injections of melarsomine (an arsenic-based drug) into the back muscles, pain management, and monitoring for complications. Cost: $500-1500+. Risks include: clots from dying worms, allergic reactions, and treatment failure. Prevention is clearly the better choice.
When to See a Vet Immediately
- Dog is not on heartworm prevention
- Coughing, exercise intolerance, or weight loss in a dog at risk for heartworm
- Annual wellness visit for heartworm testing
- Moving to or traveling to a heartworm-endemic area
- Missed doses of heartworm prevention
- Any concern about heartworm risk
How RVC Can Help
RVC provides heartworm testing and carries a full range of prevention products. Protect your pet year-round — call +853 6677 6611.
This article is for educational purposes only and does not replace professional veterinary advice. If your pet is showing any symptoms, please contact Royal Veterinary Center immediately at +853 6677 6611.