Parasite Prevention in PetsParasites may be tiny, and some we’re even unable to see with the naked eye. But, they can cause big problems for your pet. From heartworm, to internal parasites, to external parasites like fleas and ticks, the threats to your pet’s health come from many directions. So, as the weather warms up (and parasites get more active), we’re focusing on parasite prevention and the steps you can take to protect your pet (and your family) this spring and all year round.

Parasites 101

First, what exactly are we talking about here? Below are some of the most common parasites we see.

Internal parasitesheartworm, roundworm, whipworm, hookworm and giardia are among the most common internal parasites.

External parasitesfleas, ticks, and mosquitoes are common and can cause many serious problems for pets.

Lifecycle of the Heartworm

Heartworm, a type of roundworm, is one of the most insidious diseases we see, and bears a bit of focus here. The lifecycle of the heartworm is long and complex. In summary:

  • A mosquito bites and takes a blood meal from an infected animal (dog, cat, or wild species) .
  • Baby heartworms, or microfilariae, then develop in the mosquito’s body for 10-30 days.
  • The mosquito bites an uninfected pet, and the microfilariae are transmitted to the pet’s bloodstream where they continue to develop for several weeks before making their way to the pet’s heart and pulmonary arteries where they develop into foot long worms capable of reproduction.
  • After about 6-8 months after infection, the adult heartworms release new microfilariae into the pet’s bloodstream, and the process is repeated with a new mosquito bite.

Diagnosis of Heartworm Infection

Diagnosis of heartworm infection is made with 2 different blood tests, which detect the presence of either adult heartworms or microfilaria.

Adult heartwormsan in-clinic test is run using a sample of blood from your pet. The test detects a protein from the cuticle (skin) of the pregnant female adult heartworm.

Microfilariawe use the Knott’s concentration blood test, which uses a larger amount of blood from your pet than most clinics use. Many clinics use only a single drop of blood, which can easily return a false negative result. The Knott’s test, which uses a milliliter (ml) of sample, is a much more accurate test.

Treatment of Heartworm Disease

Our practice follows the current treatment protocol recommended by the American Heartworm Society. In dogs, treatment consists of the administration of an injectable drug that kills the adult heartworms. Because dead and dying heartworms may break into fragments that can obstruct oxygen flow to the heart and lungs, observation in the hospital may be recommended. Your dog will also need to be on exercise restriction for the duration of treatment (several weeks) in order not to exacerbate these problems.

We highly discourage the so called “slow kill” method of treatment. The slow kill method, which uses monthly preventive to kill the microfilaria but not the adult worms, leaves adult heartworms to wreak havoc on a pet’s heart and pulmonary vessels, often for years, before the worms die off. Our other concern with this method is that it could lead to the development of preventive resistant strains of heartworm which would nullify our greatest weapon in the fight against this serious and ubiquitous parasite.

Unfortunately, in cats there is no approved treatment available. One approach is to treat the cat’s symptoms, and hope that the cat outlives the worms. Heartworms in the cat live 2-3 years, compared with dogs (5-7 years). However, due to a reaction of the cat’s lungs to young worms,  and/or dead and dying worms obstructing oxygen flow, a respiratory emergency or sudden death may occur at any time.

Heartworm Prevention

Luckily, heartworm prevention is easy, effective, and safe. Talk to us about the best option for you and your pets. Options include a monthly oral (chew), a monthly topical used on the skin, or an injectable that can be administered in our office every 6 months. Of the three, we’ve found that the oral preventives seem to work the best and be easiest for everyone. There are several good options available, and we’d be happy to discuss them at your pet’s next preventive care exam. Heartgard is typically our first choice.

Intestinal and External Parasite Prevention

Besides heartworm, we see many other internal and external parasites in our patients. Intestinal parasites are common and can make your pet sick, usually with diarrhea, vomiting, or weight loss. It’s important to know some of these intestinal parasites can also be transmitted to you or your children, so routine testing is recommended for all pets, even if they have no symptoms.

Puppies and kittens are routinely de-wormed since they so commonly contract intestinal parasites during fetal development and/or nursing.  An important component of wellness exams is testing and inspection for parasites which is one of the reasons an annual exam is significant to the health of your pet.

One great thing about heartworm preventives is that they typically also prevent many intestinal parasites as well. A win-win!

Other ways to protect your pets, home and family include:

  • Clean up your dog’s feces right away, and clean your cat’s litter box daily to minimize chances of infection.
  • Cover children’s sand boxes when not in use to prevent cats from using them as giant litter boxes.
  • Wash your hands after cleaning up after your pet, after gardening, and when coming inside from being outdoors.
  • Prevent your pet from killing and eating small rodents.
  • Visit your veterinarian regularly for fecal and blood testing and to ensure heartworms, intestinal and external parasites are not present.
  • Make sure your pets have clean, fresh drinking water; don’t allow them to drink from sources where other animals may have dropped feces.
  • Have any new pets coming into your home tested for parasites and started on monthly preventives to ensure they don’t infect other pets.
  • Effectively prevent external parasites by using a topical or oral monthly preventive.

Our Pet Health Library provides handouts with more in-depth information regarding specific parasites. As always, we’re available to address any questions or concerns you might have. Please give us a call or schedule an appointment to make sure you have a solid parasite prevention plan for your pet.