Heartworm is a serious and potentially fatal parasitic infection that can affect dogs, cats and even ferrets. While it used to be most prevalent in pets living along the Atlantic Gulf coasts, hundreds of thousands of cases are reported each year and it has also been found in animals across the United States. Here is everything that you need to know about this supremely dangerous disease, including how best to protect your pet.
What causes heartworm?
Heartworm is caused by parasitic worm larvae that is spread from animal to animal through mosquito bites. When the mosquito bites a new host, it deposits some immature heartworms, called microfilariae, near the wound. These then enter the wound, become larvae and migrate beneath the skin. Eventually they reach the host’s heart and lungs where they mature into fully-grown worms.
How big are heartworms?
Dogs are natural hosts for heartworms, which can eventually grow as long as 12 inches long. If untreated, dogs have been known to have infestations of as many as several hundred heartworms in their bodies.
Cats are actually not the best hosts for heartworms and many larvae do not survive to the adult stage. Felines diagnosed with heartworms are often found to have between one and three juvenile heartworms, often up to around 6 or 8 inches in length.
What are the symptoms of a heartworm infestation?
Early identification of heartworm can help your pet on the road to recovery. Unfortunately, the early symptoms can very subtle and it may not be until the infection has progressed that you realise something is very wrong. In the early stages, symptoms to look out for include:
- Coughing or wheezing
- Lack of interest in playing
More advanced indications of a heartworm infection can include:
- Persistent coughing
- Difficulty breathing
- Definite lethargy
- Struggling to exercise
- Weight loss
- Loss of consciousness
How is heartworm diagnosed?
Early diagnosis is essential if your pet is to make a full recovery from a heartworm infection. The easiest and most reliable way to diagnose heartworm is for our vet to administer a small blood panel which will check for the presence of heartworm proteins. Results are usually available very quickly which means that prompt action can be taken if the sample shows that your pet does indeed have a heartworm infestation.
What is the best treatment for heartworm?
If your pet is diagnosed with heartworm, our vet may prescribe a combination of antibiotics, steroids and heartworm preventatives before starting him on the actual worm treatment. This is because antibiotics help to combat bacteria that lives inside the worms that can cause inflammation in the lungs and kidney, steroids help to reduce inflammation and the preventatives can help to kill any immature worms. The latter is particularly important because heartworm treatment only addresses adult worms.
The main treatment for adult heartworms takes at least 60 days to complete and consists of a series of injections that are placed into your pet’s lower back muscles. On the days that your pet receives the injections, he will have to stay in our vet’s care overnight, so that he can be monitored to ensure that he doesn’t experience any adverse effects. After the entire course of treatment has been completed, your furbaby will need to be tested for the presence of heartworms, and again six months later.
Should your pet continue to test positive for heartworms six months after his treatment has ended, a repeat of the program may be required.
Can I protect my pet from heartworm?
Fortunately, there are some very effective heartworm preventive treatments, although which is right for you animal will depend on his species and size. Puppies and kittens can start preventive medication from as young as six to eight weeks of age. However, if your pet is older and you are just starting a new schedule of preventive treatment, you will need to ensure that your furbaby is tested before you commence the new medication. This is because using preventive medicine in an animal that already has a heartworm medication can be dangerous.
Our East Nashville vet will be delighted to talk through the preventive schedule with you and will emphasize the importance of adhering strictly to the program. This is because being late with the medication can potentially put your pet at risk of infection.
How often should my pet be tested for heartworm?
If you have any reason to suspect that your pet may be suffering from heartworm, you should arrange to have her checked immediately. Left untreated, a heartworm infection could put the life of your pet at risk.
Many veterinarians advocate annual heartworm testing and recommend incorporating it into your regular program of preventive treatments for your pet. This will help to ensure that your pet’s prevention program is working.
Can I or my family contract heartworm from my pet?
This is a very common concern, particularly as the disease is passed by mosquitos. However, heartworm is a parasite that only affects animals. While there have been isolated incidents of heartworm infecting humans, the worm does not complete its lifecycle.
If you would like further information about heartworms, we would be happy to help. Please call our friendly and knowledgeable team today, or stop into our office on Gallatin Pike, Nashville.