|External Parasites – Ticks and Fleas|
This page is based on an episode of The Woof Meow Show which aired on May 3rd, 2014. Don Hanson and Kate Dutra talk with Dr. Dave Cloutier from the Veazie Veterinary Clinic about ticks and fleas and how to safely and effectively protect your pet from these parasites and the diseases they carry. You can listen to the show by <clicking here>
Fleas and ticks are both external parasites that can affect our dogs, our cats and even us. In talking with many pet parents, it seems they believe fleas and ticks are only a “summer problem”. However, they are a potential problem any time it is warm enough for our pets to have “muddy paws.” Since most of our pets live indoors the vast majority of the time, fleas have the potential to be an issue 365 days per year.
Ticks live outdoors and once the ground is frozen they become dormant for the winter. As soon as the ground thaws ticks wake up, crawl up vegetation and wait for a victim to come by. They do not jump onto their victim; they wait until an animal brushes against them. The tick then begins crawling on the body, usually up towards the head, with a goal of biting and attaching to the animal so they can get a blood meal. When the ticks bite, they inject a numbing agent so the bite does not sting, they then inject an anti-coagulant so the bite bleeds as they lap up their meal. Ticks also regurgitate when eating, so whatever is in the ticks stomach often transfers to the bite and then into the victim’s bloodstream. After feeding, the tick will detach itself, fall off and look for a place to lay their eggs.
Ticks can carry several bacteria that cause diseases in animals and humans. Among these are Borrelia burgdorferi (Lyme disease), Ehrlichia, Anaplasma, Babezia and others. While many animals and people can fight off these infections, some cannot. The first three of these are included as part of the test when your pet is checked for heartworm.
The Deer Tick is the primary vector for transmitting Lyme disease, but they are very tiny and hard to find on our pets or on ourselves. Fortunately, Deer Ticks are not prevalent everywhere. If you avoid areas where they live you may not need a tick preventative for your pet. For example, Dr. Cloutier indicated he does not use a tick preventative on his dog because he typically finds one tick or less on his dog per year. He does choose to use a preventative, however, when visiting family in Connecticut because he sees more ticks in one short visit there than he does the rest of the year in Maine. Whether or not your pet will acquire ticks depends on where they go and how they move through vegetation in any given area. Dr. Cloutier has clients with multiple dogs that often find ticks on one dog but none of the others.
There are ways you can minimize the chance of picking up ticks, therefore minimizing the chance of obtaining a tick-borne disease. At home, keep your yard mowed and fence off any areas where you let vegetation grow wild. While hiking, avoid areas with a high tick concentration and stay on the trail. Whether hiking or at home check your pets, and yourself, for ticks daily.
The tick obtains the organism that causes Lyme disease from the White-Footed Mouse. The tick then feeds on the deer, which becomes another vector for the disease. However, you must have a White-Footed Mouse to start the cycle and they typically stay within 30 minutes of large bodies of water. If you stay away from large bodies of water, you will be less at-risk for Lyme disease.
Lyme disease rarely affects cats, but it is possible. Because cats are such fastidious groomers, they often groom the tick off before it has had its blood meal and a chance to infect them.
When choosing a tick preventative, you need to balance the toxicity of the preventative along with its efficiency in killing ticks. In dogs, the preventatives often use two chemicals: one to kill the tick and the other to keep the tick crawling. Normally, ticks do not move much, which is why it is hard to deliver enough of the chemical to kill them. The second chemical is safe on dogs but is very unsafe for cats. Cat’s systems cannot clear this toxic chemical from their body. This is why it is absolutely essential to talk with your veterinarian when selecting tick preventatives for your pets.
Fleas are the other concern when it comes to external parasites. When topical products like FrontLine came out in the late 80s, everyone was excited about how effective it was at preventing fleas on pets. In Europe, it was originally labeled as being effective for three months. Currently, FrontLine only seems to be effective for about two weeks because the fleas have developed a resistance to the chemical.
Dr. Cloutier prefers to use a flea preventive that uses a growth inhibitor instead of a toxic pesticide. These products don’t kill the flea, but prevent them from reproducing. This product is administered to our dogs as an edible tablet they eat and for our cats is injected. When a flea feeds upon their blood, the flea consumes the growth inhibitor. The growth inhibitor prevents the flea from developing their endoskeleton and their eggs won’t hatch.
Some people worry about the growth inhibitor products because they are a chemical. Also, they are not just applied to our pet externally; they ingest the product or it is injected into them. The growth inhibitor prevents the flea from making chitin, a derivative of glucose. Mammals do not make chitin or have chitin in their systems; therefore, they are not affected by this chemical.
Fleas and ticks are very different creatures so, in some ways, it makes no sense to use the same product on both. Ticks live 99% of their life outside in the wild. They get on our pet for a couple of hours, drop off, and then go live in the external environment. The bulk of their life-cycle occurs in the wilderness which gives us very little opportunity to kill them. Fleas, on the other hand, love living in our homes and on our pets. Most of their life-cycle occurs on our pets.
It’s important to remember that most of the products we use to control fleas and ticks on our pets are toxic pesticides. They not only kill the fleas and ticks, but also have the potential to make our pets ill or even kill them if they are not used properly. Some of these products are only available from a veterinarian. Some can be ordered on-line or purchased in pet stores, as well as grocery stores and convenience stores. Too many people assume that since these products can be purchased so easily, they 1) must be effective and 2) must be safe for all applications. Unfortunately, neither is true.
A small number of these products, the growth inhibitors, are considered drugs. This means they must be approved by the Food and Drug Administration. These drugs are approved for use on a healthy animal, in a specific application, on a specific species, and at a specific dose per weight. This is also assuming it is the only product you are using. None of the other products are drugs, but are pesticides. This means that they are regulated by the Environmental Protection Agency (EPA). When evaluating a pesticide, the EPA’s primary focus is on protecting the environment from chemicals. Typically these products are not tested as stringently as drugs, nor are they tested when used with other chemical products.
Evaluating which products will be the safest and most effective with your unique family of pets is something that your veterinarian is better equipped to do than anyone else. Your veterinarian knows your pet’s health history and, if you inform them, information about others in your home as well as environmental factors that need to be considered when selecting these products. For these reasons, we recommend that everyone talk to their veterinarian before using these products.
Many people choose to make decisions regarding flea and tick preventatives without their veterinarians input. This is why the number one call to the National Animal Poison Control Center is about reactions to flea products. The number of pets that become sick, or even die due to inappropriate use of flea and tick products in the US is alarmingly high. It is not because these products are bad, but because people use the product differently than intended. Either they don’t read the instructions, use too much of the product, use the product on an inappropriate species or use the product with another product that has a cumulative toxic effect. Many people are unaware that some of the products designed for use on dogs are very toxic to cats – at any dose.
The key things to remember are: fleas and tick are here to stay, they can be a big problem and can affect both humans as well as our pets, and the best source of information you have for helping you decide what products are best for your pet, and for you, is your veterinarian.