The major external parasites of cats include fleas, ticks, mites and lice. Besides irritating the skin, these pests can transmit disease, suck blood and lead to serious skin infections. Fleas may harbor tapeworm larvae and cause Flea Allergic Dermatitis. Ticks can create localized skin infections. Mites will cause severe skin irritations. None of these pests does much to improve the lives of our feline friends.

Ticks are blood-sucking parasites closely related to spiders and scorpions. There are several species of ticks including Rhipicephalus sanguineus the Brown Dog Tick, Dermacentor viriabilis the American Dog Tick, and Ixodes species, the Deer Tick. All can transmit diseases such as Ehrlichiosis, Rocky Mountain Spotted Fever, Babesiosis and Lyme Disease, and can cause a paralytic disease in dogs called Tick Paralysis.

Ticks prefer to attach on the head and neck, in the ears, around the anus, near the shoulder blades, and between the toes. A male and a female tick will usually attach together with the female becoming quite large as she engorges with blood. The female will detach and lay thousands of eggs in the environment. (Upto 2000 at a time!) These eggs hatch into larval ticks called "seed ticks" which sometimes are seen by the thousands on some dogs. Seed ticks must feed on blood from a dog or other mammal, then they fall to the ground and molt into a "nymph" stage. Again, the nymphs must find a mammalian host, feed on blood, and again fall to the ground and molt into adults.

When the adults find a host to feed on, the cycle is completed and begins again. This whole cycle can take from 2 months up to 2 years, and will tend to proceed faster in warm, moist weather. Because all life stages can feed on your dog, and because ticks lay large quantities of eggs, tick problems can escalate rapidly. Frequent and consistent treatment will be essential to ending and controlling the problem.  ((Ticks))

There is no one-plan-fits-all strategy, but in short, killing and repelling ticks on the dog, and destroying and removing the eggs and nymphs from the house and yard are essential parts of any strategy.

It is best to work with your veterinarian to select safe and effective products. There are hundreds if not thousands of products sold today, many that are unproven and unsafe. Your veterinarian will generally have the latest improvements and safest agents available. Avoid untrained pet store personnel who have little training in chemistry and parasite control. Most are simply trying to sell you a product, not treat your pet in the best possible manner.

TOPICAL REPELLANTS such as Frontline^tm and Advantage^tm, are applied to the skin of the dog or cat where they spread out and over the entire skin area. These provide a sort of total body flea collar and are very effective in killing and repelling fleas. These agents have minimal toxicity for most pets: side effects are very rare. This is considered the "state of the art" in flea and tick control today. Avoid "knock off" products. We have seen poor performance and some severe toxic reactions from many off-brand chemicals sold in pet and retail stores.

DIPS provide quick and effective tick kill and can usually be mixed from a concentrate and poured or sponged onto your dog. You must dip about every two weeks as the dip will weaken in about that time. Do not rinse off the dip to provide residual anti-tick activity. We have had great success with Paramite Dip.

TOPICAL SPRAYS work well to quickly kill ticks, and a few will provide residual protection or prevent eggs from hatching out later. Sprays can be used between dipping, and in conjunction with topical and systemic medications. Alcohol-based sprays work best, but some people and dogs may be bothered by the fumes, so less effective water-based treatments are also available. Please ask about products currently available.

SHAMPOOS also kill adult ticks, and assist in cleaning eggs and dirt from the coat, but have minimal residual activity or effectiveness against tick eggs. Using shampoo then dipping or using a spray is the best strategy.

TICK COLLARS, if they are high quality, can help kill and repel ticks, but should be viewed as part of a tick control program and not as an end to the problem. Poor quality collars can be toxic to your dog, and can irritate the skin on the neck of your pet, so avoid the grocery store brands. Some new collars like Preventic^tm release their chemical ingredient onto the skin and not only kill and repel ticks, but prevent the transmission of tick-borne diseases. We do carry the Preventic collars but most people today opt for the topical Frontline.

FOGGERS and SPRAYS for the house and yard are useful in controlling the balance of your tick population. Newer foggers have time-release agents and providing kill for weeks after application. Many contain growth regulators to inhibit the hatching of eggs already in the environment. Foggers also apply their chemicals EVERYWHERE which happens to be where the ticks live, so these can be very useful in getting a bad tick problem quickly under control. Many sprays work in similar fashion but are better suited for direct application to baseboards and bedding areas where the heaviest infestations will occur.

Spaying the yard, grass, fences, patios and dirt areas with a yard spray made for ticks is also important to get tick problems under control. Spraying may be needed every 7-10 days in warmer weather, and you can do it yourself or hire professional exterminators to do the job for you. Be careful to keep your dogs away from freshly sprayed areas until they are dry. Most veterinarians will carry high quality yard sprays for home use.

Lice are an uncommon parasite of cats, being seen most frequently on cats from kennels, pet stores, farms and on otherwise neglected or weakened animals. Cats are affected by the biting louse Felicola subrostratus only. These pests cause intense itching, hair loss and scaling to the haircoat. They are small but can be seen with a magnifying glass and small white eggs can often be found attached to hair shafts. Lice are host specific so there is no concern for people or other pets becoming infested. ((Louse))

As lice live only on the cat, not in the environment and as they are not very resistant to insecticides, dipping the cat weekly with a pyrethrin or lime-sulfur product for 3-4 weeks should solve the problem. Every cat in a given household will need to be treated every 10 days for 4-5 weeks; most any good quality flea/tick dip should do the trick. Bedding materials and carpets should be cleaned as a precaution.

Mites are small, eight legged parasites related to ticks and spiders. They can be microscopic or large enough to see with minimal magnification. They often cause very intense irritation as they burrow, dig and feed in and on skin surfaces. Infestation with mites is called Mange, with the type of mange designated by which mite is causing the infestation, such as Sarcoptic mange.

Demodex mites are long, cigar-shaped mites that can burrow deep into the skin and feed at the roots and tissues surrounding hair follicles. This form of mange is most commonly seen in older cats that have concurrent FeLV, FIV, diabetes mellitus, immunodeficiency and chronic respiratory infections. ((Demodex Mite))

Clinical signs take two forms; some cats will exhibit the signs of otitis externa as the mites occupy the ear canal and produce a thick, waxy discharge. Some cats may not even be bothered by the presence of the mites. The other form is more generalized causing local or larger areas of hair loss, itching, scratching, redness, scaling and miliary dermatitis. Some cats may have generalized hair loss from both sides of the body yet the skin will appear somewhat normal otherwise. Diagnosis is made by finding the mites on skin scraping, ear swabs or by tissue biopsy.

Some authors advise doing nothing for small, localized spots or otic cases unless there is notable irritation to the animal. Ear preparations containing pyrethrin, rotenone or carbaryl all seem to be effective. For generalized cases the regular use of lime sulfur dip, dilute amatraz, pyrethrin or rotenone all can be effective, but dipping must continue weekly until 2 consecutive skin scrapings are negative.

Sarcoptic mange is a very intensely itchy dermatitis of cats and sometimes man. Mites burrow into the skin of the cat anywhere on the body, but prefer the ear margins, groin and axilla. The disease is very rare in the United States, occurring almost always in very ill cats

Sarcoptes scabiei is a round, spider-like mite known for having tiny suckers at the end if it's legs. The mite must live on the host to survive. Adults lay eggs in tunnels in the skin, which hatch into larvae that molt into nymphs; nymphs molt twice more before becoming adults. The whole cycle takes only 14-21 days. ((Sarcoptes))

Clinical signs include intense itching, loss of hair, scales, small bumps on the skin and thickening and darkening of the skin. The infestation usually starts on the head and progresses to the rest of the body. Areas of deep abrasion may be present from self -trauma due to scratching, but milder cases can resemble that of Flea Allergic Dermatitis or Miliary Dermatitis. Diagnosis is based on observation of the above described skin lesions and demonstration of the mites in skin scrapings.

It is always important to first check these cats for underlying conditions that may have predisposed the cat to infestation. Dipping several times with most cat-safe tick dips should cure the problem. One or two dips in Mitoban will usually work, as will dipping in lime sulfur dip. Treatment with ivermectin has proven helpful in some cases and may be used with or without dipping. Treatment of infection with antibiotics and the itching with cortisone is often necessary.

Caused by the mite Notoedres cati, this parasite is similar to demodectic mange and relatively uncommon in the United States. The mite seems to attack mainly the head and face of the cat causing the signs of intense itching, scaling, crusting, thickening and ulceration (due to scratching) of the skin. By scratching, the cat may spread the mite to other areas of the body. Kittens may become so badly infested as to cause death if left untreated. Diagnosis is usually easy to make by performing skin scraping to the head and face. ((Notoedres))

All cats in a household or group will require treatment. The mite seems easily killed with ivermectin, which should be given every 2 weeks for 3 treatments. Lime sulfur and pyrethrin dips also seem effective. While dogs do not seem to get this particular infestation, they should also be dipped if they live with infested cats.

Often called "walking dandruff", the mite Cheyletiella is a rather large mite often seen in young kittens from dirty and/or crowded conditions. It is called walking dandruff because it will appear to the naked eye that the cat simply has extremely scaly, flaky skin. When seen under the microscope, the scales are found to be mites. The mites cause symptoms of mild itching and scaling to the coat. They can be transmitted to other cats by casual contact. (very contagious) The mite spends its entire life cycle on the cat laying eggs and molting from larvae to nymph to adult, but can survive in the environment for up to three weeks under ideal circumstances. The eggs are laid glued to the hair shafts, which your vet may be able to identify under a microscope for a diagnosis. ((Cheyletiella))

Cheyletiella mites are easily killed with most dips or shampoos made for flea and tick control. Weekly baths or dips for 2 or 3 weeks should resolve the problem. As the mites can live off the cat for some time, spraying or powdering the bedding areas should often be undertaken. Fogging or area treatments may also be considered. Ivermectin with or without the dipping has also proven to aid in eradication of this pest.

Caused by the mite Lynxacarus radovsky, this is a rare mite similar to Cheyletiella and most common in warmer climates. The mite is usually present in large quantities on the skin and will cause the clinical signs of itching, easily pulled hair, scaling and a "speckled appearance" to the coat due to the egg laid on the hair shafts. This infestation may be present along with Cheyletiella mites. Diagnosis is made my combing the skin and finding the mite under the microscope.

Lyme-sulfur dip or pyrethrin dip is most effective but must penetrate to the skin surface. Usually treatment must be given every 5-7 days for upto 6 weeks. Ivermectin may also be effective but there are few reports as to its us with this particular infestation.

Ear mites are probably the most diagnosed problem of the feline ear. As often the mites cause a buildup of black, crusty debris in the ears, every time a cat owner notes this type of exudate the diagnosis seems automatic. Caused by the mite Otodectes cynotis, the mite is common to both the cat and the dog but does not attack humans. The mites burrow and feed within the ear canal, which in itself can cause signs of intense itching, but as time goes on and the mites multiply, infection of the ear canal and an allergic reaction to the mites can occur, causing the cat to scratch so much as to damage and cause infection to the ear flap and surrounding skin areas. ((Ear Mite))

The mites can easily move between animals with even minimal contact but cannot live for long without a host. While they must feed within the ear, they can move about on the coat of the cat. The mites also lay eggs in the ear canal, which hatch and molt into adult mites about every 19 days. Diagnosis is bases on clinical signs and visualization of the mites under the microscope; a procedure called ear cytology. 

Ears should be cleaned and free of wax and debris. Nolvamite or Mitox are two common preparations that are used to kill mites in the ear and should be used for three to four weeks to be certain all mites, including the ones which hatch out, are killed. Ivermectin injections and topical applications have been used with relatively good success. Infections caused by the mites may also need to be treated with antibiotic or anti-yeast preparations as well. Applying flea powder to the neck and body of your cat also helps to quickly reduce the ear mite population present. All cats in a household will need to be treated to prevent re-infestation.

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