ECTOPARASITES IN DOGS & CATS:DIAGNOSIS,TREATMENT & CONTROL MEASURES

May 8, 2022

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ECTOPARASITES IN DOGS & CATS:DIAGNOSIS,TREATMENT & CONTROL MEASURES

DR. AMIT BHARDWAJ, CANINE CONSULTANT,PUNE

What are ectoparasites?

Ectoparasites are external parasites that attach themselves to the host’s skin and may introduce pathogens through their host’s skin. They take food from your pet over a longer period of time in the form of skin flakes, blood or use it to lay eggs. The most common ectoparasites in pets are fleas, ticks and mites. But mosquitoes and lice also belong to this group of insects, so dogs and cats must also be protected from them. Because they too can smuggle pathogens into the body, some of which cause life-threatening diseases in our furry friends. Here, we list the most common ectoparasites, we tell you how you can best recognize them, as well as the corresponding treatment and prevention. Parasites that live on our pets are called ectoparasites and include fleas, ticks, lice and mites. These parasites are important not only for the direct impact they have on our pets but also because some of them carry other diseases, which are important for both pets and people. Importantly with climate change and pets travelling more frequently and more widely, the distribution of these parasites is changing.

Lice in dogs and cats

General information

These arachnids are loyal to one host and spend their entire life on them. Lice feed on the host’s blood. Lice infestations have decreased significantly, especially in domestic animals, which may be due to the increasing care of animals and the decrease in spread of stray animals. The most widespread louse species belongs to the genus Anoplura. The most relevant louse on dogs is the Trichodectes canis, and the variety that most commonly affects cats is the Felicola subrostratus.

How do I recognize lice on my pet?

In contrast to fleas, lice can be easily recognized as they don’t travel that fast and like to attach their eggs to the hair shafts. A careful examination of the fur and skin can identify lice in dogs and cats very well. You can also use a flea comb and stroke through the fur. Use adhesive tape to help, the eggs and the lice will stick to it.

Symptoms of lice infestation in dogs and cats:

Itching and increased scratching
Alopecia (sudden hair loss)
Redness and swelling of the skin
Secondary bacterial infection
Lice infestation can lead to anemia in weak and young dogs
Health effects of lice in pets

Lice are feared less because of severe secondary diseases, but mainly because an infestation affects the well-being of the animal. The pets can appear restless and irritable, the increasing scratching causes abrasions and possible infections with bacteria. Therefore, you should regularly groom the fur of your dog or cat in order to counteract these annoying pests.

What to do if lice affect cats and dogs?

The most important point in fighting lice is hygiene. If your furry friend is well cared for, the beasts won’t even nest on them. Strengthening of the immune system is also an option, then a furry friend can fend off the lice on its own with its strong immune system. Otherwise, you can comb out lice, and one or two showers for your dog can drive away the arachnids. In addition, there are numerous collars, spot-ons and powders that are effective against lice. To alleviate the itching, you can apply aloe vera gel or marigold ointment to the reddened areas. Chamomile or quark can also help.

To prevent lice infestation, you should brush your pet regularly. As with the prevention of fleas, essential oils can also make a valuable contribution and keep the insects away from your animal.

Fleas in dogs and cats

General information

Fleas are one of the few insect varieties that are named after their favorite host. As the name suggests, dog fleas like to nest on dogs, cat fleas on cats, human fleas on people, etc. However, fleas are not limited to these hosts, but change providers if they need to. The most common flea in cats is Ctenocephalides Felis. The dog flea, Ctenocephalides canis, comes second and the Archaeopsylla erinacei, the hedgehog flea, is the third most common flea parasite.

How do I recognize fleas on my pet?

An infestation can cause symptoms of different degrees in dogs and cats. These are related to factors such as the colonisation of the host (strong or rather moderate flea infestation), possible existing skin infections and other diseases and the sensitivity of the animal.

Symptoms of flea infestation:

Increased scratching and biting of the skin
Red spots
Alopecia (sudden hair loss)
Blisters on the skin
Scabs due to wound healing
Bacterial skin infection
Dermatitis

The most effective way to spot possible fleas on cats and dogs is by looking for flea droppings. Use a flea comb and first comb your pet’s fur “against the grain.” Then knock out the organic substances on a slightly damp paper towel. If there are brownish residues on the paper that turn rusty-reddish in color when crushed, there is a very high probability that this is flea excrement since flea droppings are digested blood and therefore have this red-brown color. If the color does not change, however, it’s not parasites but just dirt.

Health consequences of a flea infestation

The consequences of a flea infestation are not always harmless. Flea bites are not as serious as infected ticks or sand flies, but they can also trigger allergic reactions and even transmit pathogens.

Flea allergy dermatitis (FAD)

Fleas in dogs or cats are not only associated with increased itching and mild skin inflammation, but can also cause so-called flea allergy dermatitis (FAD). This allergy is a common reaction in pets to an increased flea infestation. The flea saliva can irritate the skin of the animal, which leads to increased scratching and under certain circumstances even cause purulent inflammation. This allergic reaction occurs in cats just as it does in dogs. A UK study in 2005 showed that 8% of the cats examined and 3% of the dogs showed symptoms of FAD. In any case, FAD should be clarified with the vet in order to be able to start targeted therapy. The use of cortisone or antibiotics cannot be ruled out if the course is severe.

Anemia due to severe flea infestation

A flea infestation can have serious consequences, especially for young dogs and cats, puppies and kittens. Fleas multiply at breakneck speed and can take up 15 times their body weight in blood per day. The already weakened organism is attacked and additionally weakened. Anemia can result. If you observe, in connection with a flea infestation, that your pet appears weak and lethargic, or has pale mucous membranes, then you should urgently visit the vet.

Tapeworm after flea infestation

The fact that fleas can also carry tapeworms does not seem to be well known. The cucumber tapeworm is an endoparasite that uses fleas as intermediate hosts and infects them as larvae. It then matures in the flea to an infectious tapeworm stage. Dogs and cats can swallow such an infected flea when they brush and bite their skin and ingest the tapeworm. The cucumber tapeworm affects dogs and cats alike and can be up to a meter long. Therefore, in the event of a flea infestation, it is also recommended to deworm the animal at the same time.

What to do if your cat or dog has fleas?

If, after the first symptoms of a flea infestation, flea droppings or live fleas are found in your pet’s fur, a quick and extensive reaction is required. The animal must be treated with an appropriate antiparasitic in order to get rid of the parasites. There is a large selection of flea products from spot-on for dogs or cats to sprays, tablets and flea powder. Each product has its advantages and disadvantages.

Natural home remedies for flea infestation

Before resorting to synthetic flea products and possibly causing side effects in your friends, try natural flea products instead. These serve not only to eliminate fleas but also as a targeted prevention of fleas in dogs and cats:

Black seed oil
Coconut oil for cats and dogs
Eucalyptus oil
Diatomaceous Earth
Brewer’s Yeast

Thoroughly clean the area around the animal

Unfortunately, a flea infestation affects not only dogs and cats, but also the entire environment of the pet. Therefore, one treatment of the animal is not enough to eradicate the entire flea population. Because only fully grown fleas find their way to the host, larvae and flea eggs, on the other hand, are distributed in the vicinity of the dog or cat. You can find them in the dog and cat basket, on carpets, in bed and on many other textiles. Therefore, the entire environment must be treated and disinfected. Clean washable textiles at at least 60° C and use natural disinfectants to avoid possible allergic reactions.

Mites in pets

General information

Mites are also an ectoparasite that pet owners should not underestimate. Their widespread habitats make the arachnids a very resilient insect. The mite lives in the ground, in the sleeping areas of pets, on carpets and other textiles. The parasitic mite likes to attack dogs and cats, other mammals and of course us humans. It nests in the fur, on and in the skin, and feeds on its host’s dander, body fluids, and other organic tissue. Mites are active all year round.

The most common mites in dogs and cats are the ear mites, of the genus Otodectes cynotis, the autumn grass mites, of the genus Neotrombicula autumnalis and fungal mite infestation (Cheyletiella) is often diagnosed in dogs and cats.

The hair follicle mites, of the genus Demodex, and the grave mites of the genus Sarcoptes, occur mainly in dogs, while the head mites, Notoedres cati, are mainly found on cats.

How do I recognize mites on my pet?

Mite infestation in dogs and cats is also associated with increased itching. The annoying beasts cause inflammation on the skin and are very uncomfortable for the furry friends. However, specific symptoms depend on the particular type of mite. While ear mites mostly show itching and rashes on the ears, hair follicle mites go unnoticed most of the time.

Symptoms of mite infestation in dogs and cats:

Increased itching
Burning of the skin
Vesicles and pustules
Rash on the skin
Red spots
Crusts
Flaking
Hair loss
Bald spots

If you recognize these symptoms in your animal, you should definitely visit the vet. After a detailed laboratory examination, they can determine the type of mite and suggest an appropriate therapy.

Health consequences of a mite infestation

While some types of mites eke out their existence inconspicuously on our pets, others can have unpleasant effects on your cat or dog. The most common signs of a mite infestation are itching, skin inflammation, usually as a result of severe itching, skin lesions or the formation of scales and crusts. However, each type of mite has different effects on the health of our animals, and some diseases can even be life-threatening. Here are the most common mite diseases in animals:

The skin disease Demodicosis

The hair follicle mites, for example, can cause the skin disease demodicosis in both dogs and cats. The localized form of this disease is basically harmless and will heal on its own. The generalised demodectic disease, on the other hand, is a serious disease in both animal species, very therapy-intensive and often indicates other underlying diseases and an additional bacterial infection. The demodicosis can be recognized by means of hairless areas, scales, crusts and nodular thickening of the skin, so-called papules. However, a final diagnosis should be made by your veterinarian. Demodicosis is rare in cats.

The Sarcoptic Mange

The highly contagious sarcoptic mange is triggered by grave mites and is transmitted through direct physical contact or an infected environment. The adult mites lay eggs in the upper layer of the skin, which hatch after a few weeks. The sarcoptic mange shows itself with very intense itching in dogs and cats. If the mange is still in the early stages, individual areas such as ears, joints, snout and also the lower abdomen are affected. In particular, increased scratching causes redness, lesions and inflammation of the skin. Encrustations, scales and cornifications are also signs of advanced grave mite mange. In humans, this condition is known as scabies and is caused by an infection.

The Notoedres Mange

This disease is very similar to sarcoptic mange, but occurs predominantly in cats. The symptoms are similar to those of sarcoptic mange and can be very uncomfortable for cats. Notoedres mange, if left untreated, can cause serious complications and even death.

External Otitis

External otitis is an inflammation of the animal’s external auditory canal and is more common than ear mange. It occurs in both dogs and cats. Not always, but often an infestation with the mite Otodectes cynotis is the cause. This type of mite settles in the auricle and secretes brownish secretions on the surface. Itching is the animal’s most common reaction. If the animal scratches too excessively, sequelae such as reddening and inflamed areas can occur, and sometimes an infection with bacteria.

What to do when cats and dogs have mites

While some effects of a mite infestation on pets will subside on their own, others can only be remedied with strong anti-parasitic agents. If you suspect mites in your furry friend, you should visit your vet who can take a sample and determine the exact type of mite.

Home remedies for mite infestation

Natural home remedies are also often used for mite infestation. Natural essential oils in particular have proven themselves useful against the annoying ectoparasites:

Coconut oil
Eucalyptus oil
Paraffin oil
Evening primrose oil
Geraniol

The oil can contribute to wound healing, scares away the parasites through the intensive essential oils and prevents inflammation. If you suspect ear mites in your dog or cat, you can simply drip the appropriate oil onto a cloth and use it to clean the ear. Repeat the procedure several times.

In the event of a mite infestation, the dog should also be washed regularly; castile soap is particularly recommended here. It does not contain any artificial additives. In addition, it is advisable to strengthen your pet’s immune system, because particularly immunocompromised animals are preferred hosts for mites and other parasites.

To prevent a new mite infestation, you should treat your furry friend regularly with appropriate repellants, spot-ons or sprays, these are also available on a natural, non-chemical basis. In addition, thorough cleaning and disinfection of the animal’s surroundings are necessary. Blankets and sleeping areas must be vacuumed, washed and disinfected. Floors, carpets and upholstered furniture should be cleaned thoroughly.

Blood-sucking ticks in dogs and cats

General information

One of the most infamous ectoparasites in our pets is the tick. This bloodsucker is not only annoying, particularly resistant and widespread, the tick also transmits serious diseases, both to animals and humans.

In our geographic region you will find mainly ticks from the family Ixodidae with their subspecies: the wood tick (Ixodes ricinus), the alluvial forest tick (Dermacentor reticulatus) and the brown dog tick (Rhipicephalus sanguineus). The latter is mostly imported from warmer regions through vacation trips. The local ticks are so-called three-host ticks and change hosts for each stage of development. The host’s blood serves as food for the tick, especially before the egg-laying phase, the parasite soaks up really full and reaches a weight up to 200 times higher than before his meal.

How do I recognize ticks on my pet?

In the case of a tick infestation, the animal usually shows no symptoms, so you should check your dog or outdoor cat for these blood-sucking pests after every walk. You can simply stroke through the fur and search the animal thoroughly. In dogs with long fur, it is much more difficult and time-consuming to find ticks. It is even more complicated to recognize ticks in the larval and nymph stage, because they are significantly smaller than their fully-grown peers. Although they can find a place to suck blood on the whole body of the host, they prefer less hairy places such as ears, armpits, between the toes or on the stomach.

The main season of ticks is between March and November, depending on the species. The common wood tick has its most active phase from March to June and again later in the year from September to November.

Health consequences of a tick bite

Ticks are so dangerous because they can transmit diseases through bacteria and viruses in the saliva while they are sucking. In addition, you cannot tell whether the tick is infected with certain pathogens or not, which makes every tick bite a potential danger for you and your furry friend. But the fact that the bloodsuckers can transmit more than just one pathogen and the signs of an infected tick bite appear much later also makes the symptoms more difficult. So it is not surprising when one speaks of the insidious tick. The most common diseases in dogs and cats after tick bites are:

Lyme disease

The tick is not the cause of Lyme disease, it is simply the carrier of the pathogen. The common wood tick as the main carrier of this subliminal disease is infected in advance with the bacteria of the Borrelia group (Borrelia burgdorferi) and passes them on to its host. As a rule, it can take up to 24 hours for the bacteria to be transmitted to the host, which is why it is even more important to search the animal immediately after the walk.

While Lyme disease can be diagnosed early in humans by the so-called wandering redness around the bite, it is absent in dogs and cats as a sign of the transmission of Lyme disease bacteria. The first symptoms may not appear until days or weeks later.

Nonspecific symptoms of Lyme disease in dogs and cats:

Limb and joint pain
Swelling in the joints
Polyarthritis
Fever
Swollen lymph nodes
Fatigue, lethargy
Inflammation of the kidneys

In order to diagnose Lyme disease in your furry friend, it is safest to examine the tick for possible pathogens. In practice, however, this is not always possible and hardly any pet owner goes straight to the vet with a tick. Blood and synovial fluid tests are possible alternatives if Lyme disease is suspected in dogs or cats, but these are not always clear because the animal does not produce antibodies. If your animal has been diagnosed with Lyme disease, antibiotics are usually administered.

Anaplasmosis

Anaplasmosis, also known as tick fever, is also transmitted by the common wood tick. The pathogens are Anaplasma phagocytophilum and after being transmitted by the tick, they attach themselves to the host’s white blood cells. They can cause serious damage to the body and even lead to death if the infection is detected too late.

Symptoms of anaplasmosis in dogs and cats:
Fever lasting several days
Muscle, joint pain and swelling
Weight loss due to refusal to eat
Vomit
Diarrhoea
Swollen lymph nodes
Enlarged liver and spleen

The veterinarian can determine an exact diagnosis based on antibodies in the blood, but only about four weeks after the infection. Here, too, antibiotics are administered. If the disease is in the early stages, the treatment prospects are very positive.

TBE – Early Summer Meningoencephalitis

The causative agent of the early summer meningoencephalitis is the flavivirus, now also known as the TBE virus. The virus enters the bloodstream via the tick’s saliva and can have serious consequences for the animal. In contrast to Lyme disease, there is no vaccine for dogs with TBE and the pathogen can pass to the host immediately after the puncture. If the disease is recognized early, it can be treated well. It is problematic, however, that dogs rarely show symptoms in the early stages and are therefore difficult to identify based on the symptoms in this phase.

The disease is particularly pronounced in animals with a weakened immune system. Therefore, in addition to early tick prophylaxis, it is advisable to strengthen the dog’s immune system before the start of tick season.

Symptoms of TBE:

High fever
Behavioural problems such as aggressiveness, lethargy
Cramps
Paralysis
Dodging when touched on the head and neck area due to pain

The diagnosis is made by the veterinarian using an antibody test. Antibiotic administration over a longer period of time is the result. Depending on the severity of the course, your furry friend must remain under observation by the vet. If the disease is already well advanced, the chances of recovery are rather slim. Therefore, if you first suspect TBE in a dog, you should consult the veterinarian immediately.

What to do if my pet has ticks

If you find a tick attached to your pet after a thorough search, don’t panic, because not all of these parasites are infected with a pathogen. According to the German Robert Koch Institute, only between 0.1% -5% of ticks in Germany are infected with the TBE virus. Borrelia-infected ticks can make up up to 30% depending on the region. If you still want to be on the safe side, you can pick up the tick after removing it and have it tested for possible pathogens by the vet. This is the safest method to detect a possible illness in your furry friend at an early stage.

How to remove ticks correctly

The tick should be removed along with its head. It is best to use tweezers or specific tick tweezers. Once you have gripped the tick, pull it out slowly. Be careful not to make any jerky movements, as this can tear off the tick’s head more quickly. Once you have pulled the tick out, it is best to crush it with kitchen paper, because these beasts are true survivors. The puncture site is then thoroughly disinfected and treated with healing ointments.

Rumours persist that oil and other liquids make it easier to remove ticks. Refrain from doing that, because the tick can suffer a shock and release all of its intestinal contents into the puncture site.

Home remedies for ticks

Prevention against ticks is the best protection. Tick prophylaxis can be carried out using repellants. These repellants have the advantage of killing ticks before they bite. These are available as a spray or spot-on. There are now plenty of herbal anti-tick remedies available. The active ingredients are similar to those of the mite and flea preparations:

Black seed oil
Coconut oil
Lemon oil
Geranium oil
Paraffinum
Lavender oil
Eucalyptus
Neem tree oil
Brewer’s yeast can also be used as prophylaxis. It can support the immune system and build an internal defense against parasites.

Sand flies – the exotic pests

General information

In Europe, sand flies are mainly found in southern countries, the most widespread species is the butterfly mosquito (Phlebotomus). As a rule, the occurrence of the sand mosquito is not relevant for the UK, but pets, mostly dogs that have been traveling with their owners in southern Europe, can bring these mosquitoes home with them.

The sand fly does not like wind and is rarely seen near bodies of water. It only becomes active after sunset, when the nights are around 20° C cool. Only the female mosquitoes suck the blood they need for the eggs to mature.

Health consequences of sand fly bites – leishmaniasis

Sand flies are carriers of leishmaniasis, an incurable disease in animals. The pathogens of the genus Leishmania enter the host’s body through a mosquito bite. After a short time, pink to red colored papules form at the puncture site. Itching and severe scratching are the result. This means that additional bacteria can be transported into the wound and hairless areas and scales are possible secondary reactions. Leishmanias can also affect organs and have already been detected in the animal’s kidneys and bone marrow.

Other symptoms of leishmaniasis include:

Increased tiredness and exhaustion
Weight loss
Muscle weakness
Swollen lymph nodes
Inflammation of the skin (dermatitis) mostly around the eyes, ears and nose
Anemia rarely occurs

A veterinary diagnosis of the disease is necessary in any case. The earlier a possible infection is detected, the better the chances of treatment. However, leishmaniasis is usually fatal in dogs and cannot be cured.

Preventing leishmaniasis

There is now a vaccination against leishmaniasis for dogs. Although this does not offer 100% protection against the outbreak of the disease, it makes sense if you want your pet to travel to endangered regions with you. Veterinarians also recommend a combination of vaccination and spot-on against mosquito bites. It is also possible to protect the animal in the evening hours with a very close-meshed mosquito net.

There are hardly any natural home remedies for sand flies. Only scents such as lavender, lemongrass, sage, lemon balm etc. can help prevent bloodsuckers from going near them. However, they are not a reliable protection.

Mosquitoes – harmless for dogs and cats?

General information

Mosquitoes are found all over Europe. Their preferred area is near bodies of water because that is where they lay their eggs. Newly hatched mosquitoes are able to fly after an hour and are more active, especially during the summer months. Both female and male mosquitoes feed on the nectar of plants and are actually not dependent on the blood of other living things for food. The females of most mosquito species only need blood to form their eggs. The proteins in the blood are used to stimulate the ovaries and to lay eggs.

Health consequences of a mosquito bite in dogs and cats

Basically, most mosquito bites are harmless to our pets. Although they appear through swelling and itching, they subside after a few days. However, particular caution should be exercised with furry friends traveling to southern Europe with their owners, because in southern areas some mosquitoes can transmit roundworms.

Heartworm disease

Heartworm disease (Dirofilaria immitis) is a rare diagnosis around here, but due to imported animals, it is more and more common in dogs and less so in cats. Infected mosquitoes transmit nematode larvae to the dog when they suck blood; these larvae pass through the blood to the lungs and can even occupy the heart. If the larvae are not killed in time, they will develop into heartworms up to 30 cm long.

Heartworm Disease Symptoms:

Chronic cough
Pale mucous membranes
Vomit
Lethargy / exhaustion
Heart, liver and kidney failure

If there is a suspicion of heartworm disease, this should definitely be discussed with the veterinarian. Diagnostic measures are taken to identify the pathogen. If the causative agent of the heartworm disease is detected, it is usually treated with a worming agent. However, the therapy can take a few months.

The skin worm disease

Another pathogen that mosquitoes can transmit and that is also related to heartworm is the skin worm Dirofilaria repens. The worm is also very rare in the UK so far; it is primarily found in areas such as Africa, Asia and southern Europe. Infected animals mostly come from these areas or have traveled to these countries. When sucking blood, the mosquito transfers the pathogen into the subcutaneous tissue of the animal, which spreads there and can develop into a full-grown worm.

Skin worm disease symptoms:

Rather inconspicuous and mild
Thickening of the skin
Itching
Skin lesions
Possible infection with other bacteria through increased scratching

This disease must also be diagnosed by the veterinarian and treated with the appropriate worming agent. If recognized early, it is comparatively mild and the animal can be completely healed. Long-term effects are not known in the skin worm disease.

Examples of Common External Parasites

Many of the common parasites can easily be transmitted from dogs to humans.

External parasites most commonly found in dogs include:

Fleas
Ticks
Ear mites (Otodectes mites)
Scabies (Sarcoptic mange)
Demodex
Lice
Cheyletiella mites (“Walking dandruff”)

How to Spot an External Parasitic Infection

Knowing how to identify symptoms of external parasites is important for both you and your dog’s health. Regular grooming and frequent checking of your dog’s skin and fur can help you find parasites that you can treat before any infection takes into effect.

Signs and symptoms of infection include:

Excessive itching or scratching
Dry, flaky skin
Dry coats
Abnormal hair loss (especially down the back) and balding spots
Black debris in ears

Treatment & Prevention

Depending on the type of parasite and where it lives on your dog (on or within the skin, in the ears, etc.) will determine what form of treatment your vet will prescribe. Topical treatments, such as creams, gels, sprays, shampoos, and lotions are typical. Other common treatment methods include flea collars, ear drops, and oral medications.

Treatment of Ectoparasitic Skin Disease in Dogs

There are a number of ectoparasiticides which are commonly in use for the treatment of ectoparasitic skin disease in dogs. These are, of course, dependent upon the particular ectoparasite which is determined to be the offender of your pet. Here are some of the products which have been developed for use in this area. Your veterinary professional will know what products to utilize and the appropriate way to administer it:

Macrocyclic lactones – Selamectin, eprinomectin and moxidectin
Cholinesterase inhibitors – Organophosphates and carbamates
Chlorinated hydrocarbons – Less popular due to environmental issues
Neonicotinoids – A class of insecticides also known as Nitroguanidine, Neonicotinoid, Chloronicotine, Chloronicotinyl
Formamidines
Oxidiazines
Isoxazolines
Insect growth regulators
Phenylpyrazoles
Pyrethrins and pyrethroids
Spinosyns
Repellents
Synergists

Your veterinary professional will determine the product he feels will work the most effectively and safely for your pet. The methods of administration of the above types of ectoparasiticides are aimed at customer convenience:

Aerosol
Powders
Shampoos
Sprays
Dips
Rinses
Mousses
Spot-ons
Injectables
Oral tablets
Oral liquids
Various types of impregnated collars

The newer spot-on method of administration has shown itself to be much more reliable and successful than some of the other methods of treatment

Dog fleas are more common during spring and summer. There are a number of ways you can cure your dog of fleas.You can either use an insecticide dip, a dog flea spray, an anti-flea drug, a dog flea collar, or a dog flea shampoo. When using any kind of dog flea treatment, you should check your dog’s skin for any sign of allergic or sensitive reaction. Also, talk to your vet before starting any kind of dog flea treatment to puppies and older dogs. Puppies should never wear dog flea collars, nor should they be powdered until they are at least eight weeks old. In addition, dog flea treatment for older dogs may be more challenging because certain changes associated with aging make them bad candidates to certain dog flea chemicals. Older dogs are also prone to dog flea allergy called dermatitis

Fleas and Flea Allergy Dermatitis

Introduction
Flea allergy dermatitis is not only the most common skin disease seen in small animal practice in most countries in the world; it is the most common disease of any organ system seen in small animal practice worldwide. Fleas parasitize animals in virtually every area on earth with the exception of locations above 1500 meters elevation and regions such as deserts with very low humidity.
The cat flea, Ctenocephalides felisis the primary flea species associated with flea infestation and flea allergy dermatitis in both the dog and the cat in most studies. The average car flea life cycle involving development through egg, larvae, pupa and cocoon, and the adult and takes between 3 and 4 weeks. However the life cycle can be as short as 12 days or as long as 140 days. Adult cat fleas are obligate permanent ectoparasites, attracted to the host by warmth, movement, changes in light intensity, and respiratory carbon dioxide.
New advances in the understanding of the biology of the flea and new methodologies available to combat multiple life stages of the flea both on and off the animal have revolutionized our ability to deal with this disease. It is crucial to remember that the adult cat flea is an obligate parasite. However, since the bulk of the flea lifecycle (eggs, larvae, and pupa) occurs in the environment, environmental issues must always be addressed. Historically, flea control has required treating both the animal and the environment with a combination of insecticides and, more recently, insect growth regulators. Today, either topical or systemic anti-flea therapy may be the only management required. The new agents that have created this paradigm shift include imidacloprid, fipronil, selamectin, nitenpyram, lufenuron, methoprene, and pyriproxifen.
Skin disease associated with fleas is a complex group of hypersensitivity phenomenon involving at least four immunologic processes; immediate hypersensitivity, late-onset immediate hypersensitivity, delayed hypersensitivity, and cutaneous basophil hypersensitivity. Blood consumption by female averages 13.6 microliters/day (75 female cat fleas can consume 1 ml/day). The majority of blood is passed out as partially digested feces to feed flea larvae.
The management of flea allergy dermatitis requires the prevention of flea bites plus the disruption of the life cycle of the flea. New products that have become available over the past 15 years have exponentially increased our ability to initiate flea control and manage flea allergy dermatitis.
Modern Flea Control
New, considerably less toxic prescription products that also are much easier to use are available that kill adult fleas and disrupt the flea life-cycle. Most insecticides can effectively kill fleas; preventing reinfestation is the problem. Insuring long-term pet owner compliance is required for on-going flea control. The comparatively recent development of both insecticides and insect growth regulators with novel and convenient dosage forms (such as spot-ons, collars, and oral products) coupled with prolonged residual activity has dramatically improved pet owner compliance and hence prevented reinfestations. Although insecticidal resistance most often is suspected when flea control measures have failed, lack of control more often results from lack of understanding of flea biology, poor application technique, and too infrequent reapplication of the products.
The goals of flea control should be elimination of existing fleas on affected animals, continued elimination of fleas acquired from infested premises, and the prevention of reinfestation. In order to accomplish these goals, an integrated flea control plan must be instituted. Effective residual adulticides must be used to kill fleas plus provide residual killing activity and insect growth regulators must be use to used to disrupt flea reproduction. In addition, mechanical control procedures such as cleaning pet’s blankets, beds, pet carriers, and throw rugs and vacuuming or removing furniture that can house pre-adult fleas must be instituted. Preventions of pests that can carry fleas (rats, opossums, squirrels, raccoons, skunks, feral cats) from entering crawl spaces, foundation vents, porches and garages also is important.
Modern Flea Control Products
New spot-on prescription products are excellent products with superior efficacy, safety, and residual activity. These products need to be applied directly to the skin, not to the haircoat. Our very strong clinical impression at UC Davis is that dogs and cats with severe flea hypersensitivity experience much better efficacy with these products applied every 3 weeks instead of monthly. Our clinical impression remains that either bathing or swimming degrades the efficacy of all of these products. Over-the-counter (OTC) competing products commonly are advertised as ‘just as good as what you can get from your veterinarian’ plus ‘less expensive’. In general, these products contain concentrated permethrin or other synthetic pyrethroids. All indications are that these OTC products do not have either the efficacy, residual activity, or the safety profile of the spot-on prescription products.
Imidacloprid (Advantage®, Bayer)
Advantages–larvicidal on the animal and kills/debilitates adult fleas on contact, ease of application
Disadvantages–does not have repellent action, diminished efficacy after bathing or swimming, does not have activity against ticks, occasional application site reactions
Bottom-line–good narrow-spectrum product for fleas
(Canada–Imidacloprid & Moxidectin–Advantage Multi®, Bayer)
(Europe–Imidacloprid & Moxidectin–Advocate®, Bayer)
Fipronil & S-Methoprene (Frontline® Plus, Merial), Fipronil (Frontline® Spray, Merial)
Advantages–kills adult fleas, disrupts flea life cycle, ease of application, kills ticks, spray–rapid dispersion and coverage,
Disadvantages–does not have repellent action, some diminished efficacy after bathing or swimming, occasional application site reactions, spray is labor-intensive
Bottom-line–good broader spectrum product
Imidacloprid & 44% permethrin (Advantix®, Bayer)
Advantages–larvicidal on the animal and kills/debilitates adult fleas on contact, interrupts flea life cycle, repellant ‘flushing’ activity of permethrin, ease of application, also kills ticks and mosquitoes
Disadvantages–dog only product, do not use on cats, diminished efficacy after bathing or swimming, occasional application site reactions?
Bottom-line–good broader spectrum product, dog only product
Selamectin (Revolution® [USA]; Stronghold® [Europe], Pfizer)
Advantages–broad spectrum against many internal and external parasites, kills adult fleas plus larvae and eggs, kills ticks, kills some ectoparasitic mites (Sarcoptes, Notoedres, Cheyletiella, Otodectes), ease of application,
Disadvantages–does not have repellent action, diminished efficacy after bathing or swimming, slower efficacy?, application site reactions?
Bottom-line–good broader spectrum product
Nitenpyram (Capstar^TM, Novartis)
Advantages–very rapid response with visual results, kills 100% of adult fleas within 6 hours, short-acting, ease of oral administration, give every 24-72 hours (half-life in dogs is 2.8 hours, half-life in cats is 7.7 hours) very safe product, adverse reactions not seen yet
Disadvantages–does not have repellent action, does not disrupt flea life cycle, short-acting, does not have activity against ticks
Bottom-line–good narrow spectrum product, use with spot-ons initially for rapid response, not for use as sole therapy, use in dogs requiring frequent shampooing, compliance problems?
Lufenuron (Program®, Novartis; Sentinel® [lufenuron + milbemycin oxime])
Advantages–oral product, very safe product without known mammalian toxicity, adverse reactions not seen yet,
Disadvantages–does not kill adult fleas or pupa, time lag–60-90 days required to disrupt flea life cycle, does not have repellent action, adult flea must feed on animal to ingest, does not have activity against ticks, must give with food
Bottom-line–use with spot-ons for long-term control, not for use as sole therapy unless very closed environment, treat all animals, use in dogs requiring frequent shampooing, compliance problems?
Pyriproxifen (Nylar®) containing collars–Pyriproxifen & amitraz collars (Preventic PLUS®, Virbac), dogs only!, no longer available in the USA
Pyriproxifen & 2% permethrin (KnockOut® Collar for Dogs, Virbac), no longer available in the USA
Pyriproxifen (KnockOut® Cat & Kitten Collar for Dogs, Virbac), no longer available in the USA
Advantages–ovicidal and larvicidal for fleas, UV stable juvenile hormone analogue, translocates to bedding, IGR efficacy for 3 months, Preventic Plus® adds tick protection
Disadvantages–long-term residual status may affect beneficial insects
Bottom-line–very useful adjunct to spot-ons or spray products, useful in dogs requiring frequent shampooing
Synthetic pyrethroid containing pump sprays (variety of manufacturers)
Advantages–daily use in dogs requiring frequent shampooing
Disadvantages–frequency of application, compliance, poor residual activity
Bottom-line–rarely used as sole therapy unless very closed environment, use in dogs requiring frequent shampooing, compliance problems?
Personal Recommendations
Flea control must be regionalized and often personalized based on severity of possible infestation in your locale, number of dogs and cats in the environment, indoor/outdoor/run free status, infested pests and strays in the environment, finances of the owner, and severity of disease vs. magnitude of the infestation.
‘The average dog or cat’ will respond to fipronil and S-methoprene, imidacloprid with or without lufenuron, or selamectin as sole therapy.
Severely flea allergic dogs will require fipronil and S-methoprene or imidacloprid plus permethrin, plus either nitenpyram, with or without lufenuron.
Severely flea allergic cats will require spot-on preparations plus nitenpyram with or without lufenuron. Pump-sprays also may be beneficial.
Animals with tick exposure benefit from fipronil and S-methoprene, imidacloprid plus permethrin (dogs only!), and pyriproxifen & amitraz collars (dogs only!).

Ticks

Introduction
Tick infestation and tick bite hypersensitivity are highly variable regional skin diseases. In some parts of North America, ticks are a major problem, while they are comparatively rare in many other areas. Ticks cause morbidity either by direct irritation from their bites, initiate hypersensitivity, or act as vectors for multiple bacterial, viral, rickettsial, or protozoal diseases.
Modern Tick Control Products
Fipronil & S-Methoprene (Frontline® Plus, Merial), Fipronil (Frontline® Spray, Merial)
Advantages–kills ticks, ease of application, residual activity, also kills fleas
Disadvantages–does not have repellent action, some diminished efficacy after bathing or swimming, occasional application site reactions
Bottom-line–good product for tick control
Imidacloprid & 44% permethrin (Advantix®, Bayer)
Advantages–kills ticks, ease of application, also kills fleas and mosquitoes
Disadvantages–dog only product, do not use on cats, diminished efficacy after bathing or swimming, occasional application site reactions?
Bottom-line–good broad spectrum product, dog only product!
Selamectin (Revolution® [USA]; Stronghold® [Europe], Pfizer)
Advantages–kills ticks, also broad spectrum against many internal and external parasites, kills adult fleas, kills some ectoparasitic mites (Sarcoptes, Notoedres, Cheyletiella, Otodectes), ease of application,
Disadvantages–diminished efficacy after bathing or swimming, application site reactions?
Bottom-line–good product for tick control
Amitraz containing collars–(Preventic®, Virbac), dog only product
Advantages–detaches and kills ticks, residual activity for 3 months
Disadvantages–dog only product
Bottom-line–good product for tick control
Personal Recommendations
Tick control must be regionalized and often personalized based on severity of possible infestation in your locale, number of dogs, indoor/outdoor/run free status, infested pests and strays in the environment, finances of the owner, and severity of disease vs. magnitude of the infestation.
‘The average dog’ will respond to fipronil and S-methoprene, imidacloprid and permethrin, selamectin, or an amitraz collar as sole therapy.
Severely affected dogs benefit from the combination of a spot-on product (fipronil and S-methoprene, imidacloprid and permethrin, or selamectin) plus an amitraz collar.

Acariasis–Sarcoptic Acariasis, Notoedric Acariasis, Cheyletiellosis

Introduction
Canine sarcoptic acariasis “Scabies” is an intensely pruritic, highly contagious, transmissible canine dermatoses caused by the epidermal mite Sarcoptes scabei var. canis. Transmission is usually by direct contact with an infested dog. There is evidence that clinical disease is a multi-factorial hypersensitivity reaction. Sarcoptic acariasis may be increasing in prevalence with the advent and increased popularity of newer insect-specific flea control products. Formerly, we may have stopped scabies infestation when we were simply attempting to kill fleas.
Notoedric acariasis or feline scabies is a rare contagious mite infestation caused by the sarcoptid mite Notoedres caticharacterized by crusting with extreme pruritus. The disease is rare in most parts of the United States, but may be found in localized endemic areas. Similar to sarcoptic acariasis, notoedric acariasis may be increasing in prevalence with the advent of some newer insect-specific flea control products. Notoedres is highly contagious in cats and occasionally, may affect dogs or humans.
Cheyletiellosis or Cheyletielladermatitis is a contagious mite infestation seen in domestic animals, wildlife and humans characterized primarily by scaling and crusting caused by different, but very similar, species of Cheyletiella mites. It may be seen more commonly in areas of the world where concerted flea therapy is not necessary or not consistent. Cheyletiella dermatitis may be increasing in prevalence on a wider basis with the advent of some newer insect-specific flea control products. Infestations have been reported in dogs, cats, rabbits, squirrels, poultry, foxes and humans. This disease may not be as uncommon as previously thought since many veterinarians have a very low index of suspicion and do not look for it. It is reported that the mites may live in an animal’s environment for extended periods of time.
Modern Acariasis Control Products
It is beneficial for the management of all 3 diseases to isolate the affected animal(s) and clean the premises, disposing of the animal’s bedding or thoroughly cleansing it. For the management of canine sarcoptic acariasis, all dogs on the premises and any other dogs with significant contact with the affected dog should be treated. For the management of feline notoedric acariasis, all cats on the premises and any other cats with significant contact with the affected cat should be treated. The treatment of in-contact cats in households with canine sarcoptic acariasis and the treatment of in-contact dogs in households with feline notoedric acariasis are more controversial. If skin disease is present or if initial species-restricted therapy is ineffectual, treatment of the other species should be considered. All dogs and cats on the premises and any other dogs or cats with significant contact with the affected animal should be treated when Cheyletiellosis is diagnosed.
The traditional approach of using weekly keratolytic shampoos followed by parasiticidal dips has been superseded by newer less labor-intensive methods of therapy. Lime sulfur (LymDip®, DVM Pharmaceuticals) is still used in circumstances where safety is an issue especially in very young animals.
Systemic corticosteroids may be used adjunctively to control pruritus during the first week of therapy. Paradoxically, pruritus may actually increase initially because of increased antigenic load.
Selamectin (Revolution® [USA]; Stronghold® [Europe], Pfizer)
Selamectin is used for mite infestations most commonly at label dosages every 2 weeks for a minimum of 3 applications
Advantages–kills all 3 ectoparasitic mites, approved for use on dogs and cats, label claims, ease of application, also kills adult fleas and ticks, also broad spectrum against many internal and external parasites
Disadvantages–none
Bottom-line–Good product to treat small animal acariasis
Ivermectin (Ivomec®, Merial; DVMectin®, DVM Pharmaceuticals)
Ivermectin 230 micrograms/kg or 1/10 cc/10 lbs body weight per os, for a minimum of four weekly dosages. Certain dog breeds are potentially more sensitive to this drug owing to the MDR1 mutation which diminishes the functionality of the blood-brain barrier. At the dosages used for scabies, this problem is of most concern for Collie Dogs and Shetland Sheep Dogs. Serious adverse neurologic reactions to ivermectin have been seen in Collie Dogs, Shetland Sheep Dogs, Border Collies, Australian Shepherds, and, less commonly, a variety of other breeds.
Advantages–inexpensive, efficacious
Disadvantages–toxicity in dogs with MDR1 mutation, Ivomec® is a product licensed for use in cows
Bottom-line–efficacious product to treat small animal acariasis
Milbemycin oxime (Interceptor®, Novartis Animal Health)
Another avermectin, is also efficacious to treat acariasis. Recommended dosages vary from 1X to 2X the monthly heartworm dose given once weekly for four weeks. Milbemycin may be a ‘safer’ avermectin that ivermectin, but caution should still be exercised in at-risk breeds.
Advantages–efficacious, licensed for use in dogs, more safe than ivermectin?
Disadvantages–toxicity in dogs with MDR1 mutation
Bottom-line–efficacious product to treat small animal acariasis
Amitraz (Mitaban®, Pharmacia & UpJohn)
Amitraz is an MAO inhibitor and should not be used on dogs or applied by anyone taking other MAO inhibiting drugs. Amitraz should not be used on cats. Amitraz rinsing should be performed either outdoors or in an open garage. Rubber gloves should be worn by the applier.
Advantages–efficacious, licensed for use in dogs
Disadvantages–greater potential for toxicity
Bottom-line–other products with equal or greater efficacy have less potential for toxicity
Personal Recommendations
It is important to maintain an index of suspicion for all 3 mite infestations as a cause of pruritus in dogs and cats. Cheyletiellosis may present as exfoliation with minimal pruritus. All 3 contagious mite infestations may be increasing in frequency of occurrence.
Most dogs and cats with mite infestations will respond to selamectin, ivermectin, or milbemycin.
Based on approval for use on dogs and cats for mite infestations, selamectin is the drug of choice for all 3 mite infestations. If financial constraints preclude usage, ivermectin can be used as an alternative.