Treating canine scabies, Veterinary Practice
Treating canine scabies
- 1 Treating canine scabies
- 2 Clinical features
- 3 Differential diagnosis
- 4 Diagnosis
- 5 Treatment
- 6 Prognosis
- 7 David Grant
- 8 Canine Scabies Treatment
- 9 Overview
- 10 Sarcoptic Mange Home Remedy
- 11 Prescription Mange Treatment
- 12 Canine Scabies on Humans
- 13 Prevention & Elimination
- 14 Scabies in Dogs
- 15 Symptoms of A Dog Having Scabies
- 16 Diagnosis and Treatment
- 17 Scabies: Symptoms, Complications, Treatment and Prevention
- 18 Definition
- 19 History
- 20 Epidemiology
- 21 Types
- 22 Risks associated with scabies
- 23 Life cycle
- 24 Causes
- 25 Symptoms
- 26 Complications
- 27 Diagnosis and test
- 28 Common sites for scabies rash
- 29 Treatment and medications
- 30 Prevention
An overview of the clinical features, diagnosis and treatment options for canine scabies, which is caused by a superficial burrowing mite
Canine scabies (sarcoptic mange) is one of the oldest known skin diseases. It is caused by the superficial burrowing mite Sarcoptes scabiei var canis (Figure 1). Affected animals rapidly develop hypersensitivity to the mite, resulting in severe pruritus.
Scabies is highly contagious and there may be a history of contact with other dogs, also exhibiting pruritus, in kennels, grooming facilities, parks or in the household. In the UK urban foxes are a source of infestation. The condition is progressive without treatment and will become generalised.
Lesions include papules, alopecia, erythema, crusts and excoriations. In the early stages, lesions may be subtle and consist of mild pruritus, scaling and fine crusting, especially on the edges of the pinnae. They then extend to involve the facial area (Figure 2). As the disease progresses, there is involvement of the elbows, hocks, brisket, ventral abdomen and eventually most parts of the body.
Affected dogs may develop systemic signs of disease such as anorexia with weight loss, and a peripheral lymphadenopathy is common. Severely affected dogs will incessantly scratch and bite, causing excoriation (Figure 3). Severe neglected cases can result in death and scabies is also a common cause of death in urban foxes.
A rare form of the disease is one involving severe generalised crusting, analogous to a human variant called Norwegian scabies. In these cases, there are usually multiple mites and an underlying immune suppression should be suspected.
In a multi-dog household, it is possible that some dogs will harbour mites but not show signs. In time, without veterinary intervention, hypersensitivity develops and these dogs will also become pruritic.
Contagion to humans is common. Lesions occur in contact sites with the dog, arms and abdomen, for example, and are extremely pruritic. These lesions generally spontaneously disappear with appropriate treatment of the dog, although communication with the family physician is advisable.
- Allergic skin diseases (atopy, food, flea)
◽ In the early stages, scabies can mimic atopic dermatitis in particular and respond to antiinflammatory doses of glucocorticoids. This response is lost as the disease becomes more generalised and there have been cases where even immunosuppressive doses of glucocorticoids failed to control pruritus
- Malassezia dermatitis
- Superficial pyoderma
◽ If combined with Malassezia, the resulting pruritus can be as severe as that of scabies
- Pemphigus foliaceus if severe crusting is present
A history of severe pruritus, increasing in severity with time, and increasingly poorly responsive to glucocorticoids is suggestive. If acaricidal treatments have been used, it is important to check compliance. Pups bred in poor husbandry conditions are susceptible.
A physical examination should be undertaken with attention to typical lesion sites. Rubbing the ear margin between the thumb and forefinger causes the dog to scratch. This pinnal-pedal reflex is highly suggestive of scabies, although not 100 percent positive. It should prompt treatment even if other tests are negative.
Tape strips should be done to rule out Malassezia and superficial pyoderma. Also take superficial and deep skin scrapings. Multiple samples (up to 10) are advised, as Sarcoptes is very difficult to find except in the Norwegian type mentioned above. Excoriation sites should be avoided. Scrapings can be taken from the edge of lesions. A single mite or egg is diagnostic.
ELISA assay is a useful test in chronic cases. The test detects IgG antibodies against Sarcoptes antigens. It is highly sensitive and specific. False negatives may be obtained in early cases, as there is a time lag of three to five weeks after infestation for seroconversion to take place. False positives may occur due to persistence of antibodies for several months after successful treatment.
Dermatohistopathology is also useful. Non-specific findings include epidermal hyperplasia, superficial perivascular dermatitis with lymphocytes, mast cells and eosinophils (Hnilica and Patterson, 2017). Mite segments are very occasionally found within the stratum corneum and upper epidermis (Figure 4).
In the presence of suggestive clinical signs, and when sampling has failed to find mites, a therapeutic trial is recommended. A product with a licence for Sarcoptes should be selected, and is best administered by a veterinary surgeon or nurse to eliminate compliance problems.
Systemic treatments are suggested for a therapeutic trial for accurate dosing and better compliance (Hnilica and Patterson, 2017). Three monthly checkups are suggested, as most cases will resolve in that time.
Canine scabies is not always an easy disease to diagnose but treatment is straightforward in most cases. There is no lack of products with a licence for the treatment of canine scabies and any of them will be highly effective if used according to the manufacturer’s instructions.
Examples of suitable products include sprays (fipronil), washes (lime sulphur dip), spot-on products (selamectin, imidacloprid/moxidectin) and chewable tablets (sarolaner). These examples are not exhaustive and the choice of product will depend on an individual clinician’s preference.
All dogs in the household should be treated, bedding should be destroyed and the environment treated with parasiticidal sprays, using products suitable for flea control.
There is usually a response within two weeks with maximum effect in six to eight weeks. Glucocorticoids may be used to help control pruritus in the first week or so, but only in confirmed cases and not in conjunction with therapeutic trials.
Formulating a year-round parasite control programme that includes measures against fleas, ticks, other mites and endoparasites provides effective protection against canine scabies.
The main limiting factor with scabies treatment is a failure of compliance. Measures taken to avoid this include monthly checkups (with reminders), and nurses or veterinary surgeons administering the treatment. In these cases, the prognosis is very good.
|Hnilica, K. A. and Patterson, A. P.||2017||Small animal dermatology: a color atlas and therapeutic guide, 4th ed.|
David Grant, MBE, BVetMed, CertSAD, FRCVS, graduated from the RVC in 1968 and received his FRCVS in 1978. David was hospital director at RSPCA Harmsworth for 25 years and now writes and lectures internationally, mainly in dermatology.
Canine Scabies Treatment
Table of Contents
«Canine scabies, or Sarcoptic mange, is caused by a mite. It can cause your dog’s skin to itch, and you may notice red bumps and a scaling or hardening of the skin. Skin infections may result due to scratching of affected areas.
Options for canine scabies treatment include prescription and over the counter approaches. Both can be highly effective. It is contagious, so all dogs and pets that have been in contact with the infected dog should be treated.»
Vets will often recommend that treatment starts prior to confirming the presence of mange mites (mites are sometimes missed or are removed by the scratching dog). Antibiotics may be needed for any infection that results from scratching. Treatment lasts 4 weeks for most dogs, but can be extended to 8 weeks for larger infestations. Be sure to disinfect areas where your dog lives to avoid a repeat case of the problem.
Sarcoptic Mange Home Remedy
The safest mange home remedy for scabies in dogs is to use a lime-sulfur dip such as the over the counter product Naturasil, with one treatment every 5 days until the condition clears. Lime-sulfur is the FDA approved way to treat canine mange and scabies. The Naturasil product has the added advantage of being mixed into the shampoo before use, making the treatment feel familiar to your dog.
If using a dip as your canine scabies treatment approach, typical instructions are to prepare a tub with the medication and put your dog in it for 15 minutes. Use gloves to ensure that you do not catch scabies from your pet and use in a well ventilated area.
Prescription Mange Treatment
For severe generalized cases (where the mange spread over your dogs body), then glucocorticoid therapy may be helpful during the first 3 to 5 days. The prescription medication ivermectin may also be of help. This medication can have side effects in herding dogs (Collies), so your vet may try a short trial to see how your dog tolerates the medication. Side effects include tremors and lack of muscle coordination (ataxia). Treatment lasts 3 to 4 weeks.
If you are using a prescription dip, as an added step a bath in a benzoyl peroxide shampoo such as Pyoben might help when used before the first treatment. Be sure to follow the dip manufacturer’s directions. Mites live in hair follicles and benzoyl peroxide helps the hair follicles cleanse themselves of the dying mites. Since benzoyl peroxide is drying, you will need to use a moisturizing conditioner after the baths. The Naturasil approach combines both steps by mixing the lime-sulfur active ingredient into the shampoo you currently use on your pet, making the treatment feel familiar to your dog.
It is not unusual for your dog’s condition to worsen during the first days of treatment. Depending on the severity of the mange, treatment can be as short as 4 weeks to as long as 8 weeks.
Other additional treatment approaches including cutting the hair around the papules or lesions, cleaning any wounds and the use of antibiotic ointment to avoid infection.
To speed healing and provide extra support, a homeopathic such as Skin and Coat Tonic may be of some help.
Canine Scabies on Humans
It is possible for humans to be infected with the scabies mite after close contact with a dog. Symptoms are itch and skin irritation. Most cases occur on the arms. The condition lasts several days and will resolve on its own.
Prevention & Elimination
For scabies in dogs be sure to thoroughly clean both the indoor and outdoor areas where your dog lives to make sure that all mites are removed. Use an indoor safe cleaner such as Benzarid.
References for Canine Scabies Treatment
Hound Health Handbook
Canine Scabies: An Update
Didier-Noel Carlotti, Doct.-VГ©t., DECVD
Cabinet de Dermatologie VГ©tГ©rinaire, Heliopolis B 3
Bordeaux-MГ©rignac, France (EU)
Scabies in Dogs
Scabies in dogs are highly contagious and can spread to and from other dogs and house pets. The mites are also transferable to people. They are spread by direct contact with an infected animal and by sharing contaminated bedding, grooming equipment, etc.
The life cycle of the sarcoptic mites is about 17 to 21 days. The whole cycle occurs on the skin of an infected dog.
Female mites lay eggs a few millimeters under the skin of the dog. The eggs hatch in 3 to 10 days and mature into adults. They then mate and lay eggs thus repeating the whole cycle.
As you can imagine, scabies can spread quickly and easily out of control in a very short period of time!
Symptoms of A Dog Having Scabies
Sarcoptic mites usually attack the skin of a dog’s ears, the elbows and the hocks, as well as the face and the underside of the chest.
The hallmark symptom of scabies in dogs is intense itching resulting in scratching, biting, chewing, and licking.
Because of the discomfort caused by intense itching, the dog understandably will get increasingly irritated and may lose interest in things that he normally enjoys, such as food, games, walks, etc.
Another typical symptom of scabies in dogs is crusty ear tips.
Without treatment, the itch-scratch-itch cycle can quickly result in self trauma and hair loss. The skin in the affected areas will become inflamed and crusty lesions will form.
In serious cases, the dog can lose his hair in large areas of his body. The skin will become thick, scaly, and be covered with crusts and scabs.
Did you know that you can do a simple test (called the “Pedal-Pinna Reflex” Test) to see if your dog has scabies?
Simply rub or scratch your dog’s ear flap (pinna) between your fingers and, if your dog has scabies, he will almost always by reflex scratch on the same ear!
Diagnosis and Treatment
If you suspect that your dog has scabies, be sure to get him to the vet for a proper diagnosis. The vet will make the diagnosis by examining skin scrapings under a microscope.
Unfortunately, it is not easy to find sarcoptic mites. Many vets misdiagnose dogs with scabies as having atopic dermatitis.
If the vet cannot find any mites but the symptoms strongly suggest scabies, sometimes he will give a trial treatment of Ivermectin medication to the dog. A positive response to the treatment confirms the diagnosis of scabies.
In the past, the most common conventional treatment of scabies was the use of dips (such as amitraz and lime-sulfur dips). However, scabies mites have developed resistance to quite a few chemical dips. In addition, dips can be toxic to humans as well as to dogs.
Newer conventional medications for scabies include the use of some flea control medications (such as Revolution® and Frontline Plus®) that are also effective against mites.
Oral ivermectin is an off-label (i.e. not FDA approved) medicine for treatment of scabies.
If your dog is a Collie, Sheepdog, or other herding breeds and their crosses, DO NOT use Ivermectin because it may cause potential toxic effects in these dog breeds.
As there are various types of treatments available to treat scabies, be sure to consult with your veterinarian who can best decide the most appropriate treatment for your dog.
Whatever the treatment chosen, you need to treat all pets in the household or who have been in contact with the infected dog.
Besides treating the infected dog and other household pets, you also need to treat the home environment to prevent re-infestation. All bedding should be washed in hot soapy water.
Carpets and upholstery should be vacuumed and if possible washed.
The house should be sprayed with a residual insecticide used for killing adult fleas. The spraying should be repeated every 2 weeks during the treatment period.
Scabies: Symptoms, Complications, Treatment and Prevention
Scabies is an itchy skin condition caused by a tiny burrowing mite called Sarcoptes scabiei. The presence of the mite leads to intense itching in the area of its burrows. The urge to scratch may be especially strong at night.
Scabies is contagious and can spread quickly through close physical contact in a family, child care group, school class, nursing home or prison. Because of the contagious nature of scabies, doctors often recommend treatment for entire families or contact groups.
Scabies is readily treated. Medications applied to your skin kill the mites that cause scabies and their eggs, although you may still experience some itching for several weeks.
Scabies has been observed in humans since ancient times. Archeological evidence from Egypt and the Middle East suggests scabies was present as early as 494 BC. The first recorded reference to scabies is believed to be from the Bible – it may be a type of “leprosy” mentioned in Leviticus c. 1200 BC or be mentioned among the curses of Deuteronomy 28. In the fourth century BC, Aristotle reported on “lice” that “escape from little pimples if they are pricked” – a description consistent with scabies.
The Roman encyclopedist and medical writer Aulus Cornelius Celsus (25 BC – 50 AD) is credited with naming the disease “scabies” and describing its characteristic features. The parasitic etiology of scabies was documented by the Italian physician Giovanni Cosimo Bonomo (1663–1696) in his 1687 letter, “Observations concerning the fleshworms of the human body”. Bonomo’s description established scabies as one of the first human diseases with a well-understood cause.
In Europe in the late 19th through mid-20th centuries, a sulfur-bearing ointment called by the medical eponym of Wilkinson’s ointment was widely used for topical treatment of scabies. The contents and origins of several versions of the ointment were detailed in correspondence published in the British Medical Journal in 1945.
Approximately 300 million cases of scabies are reported worldwide each year. Natural disasters, war, and poverty lead to overcrowding and increased rates of transmission.
In industrialized countries, scabies epidemics occur primarily in institutional settings, such as prisons, and in long-term care facilities, including hospitals and nursing homes. Scabies occurs more commonly in fall and winter months in these countries. Prevalence rates for scabies in developing nations are higher than those in industrialized countries.
A survey of children in a welfare home in Pulau Pinang, Malaysia found that the infestation rate for scabies was highest among children aged 10-12 years. The disease was more commonly evident in boys (50%) than in girls (16%). The overall prevalence rate for scabies was 31%.
Of 200 dermatology outpatients in Sirte, Libya, with scabies, the following distribution was found:
- Females – 59%
- Children – 37.5%
- Military personnel – 18%
While many accounts of the epidemiology of scabies suggest that epidemics or pandemics occur in 30-year cycles, this may be an oversimplification of its incidence, since these accounts have coincided with the major wars of the 20th century. Because it is not a reportable disease and data are based on variable notification, the incidence of scabies is difficult to ascertain.
Scabies is clearly an endemic disease in many tropical and subtropical regions, being 1 of the 6 major epidermal parasitic skin diseases (EPSD) that are prevalent in resource-poor populations, as reported in the Bulletin of the World Health Organization in February 2009. Prevalence rates are extremely high in aboriginal tribes in Australia, Africa, South America, and other developing regions of the world. Incidence in parts of Central and South America approach 100%. One report suggests the highest reported rates of the crusted scabies in the world is in remote Aboriginal communities of northern Australia.
Many people think that there are different kinds of scabies, but the truth is there is only one type of mite that causes the condition, which is the Sarcoptes scabiei mite. When talking about the classification or types of scabies, what they usually refer is the different ways that the rash can appear. These include:
Typical scabies: These are itchy rashes that appear on the hands, wrists and elsewhere; however, the scalp and face are spared.
Nodular scabies: This type appears as itchy bumps in the groin, armpits and genital areas.
Infantile scabies: A scabies infestation that appears on a child or infant, and are most often characterized by rashes on the hands and feet, as well as the face and scalp.
Another type is complicated scabies, and unlike the others, it does not specify where the rash occurs – rather, this is when scabies occurs with another skin-related condition, such as dermatitis, urticaria, or impetigo (infection).
Scabies may also be classified according to where the infestation breaks out. For example, scabies that affects occupants of a residential facility, such as boarding schools, rest homes, hospitals, prisons and camps is called institutional scabies.
The most severe type of scabies is crusted scabies. Also known as Norwegian scabies, as it was first identified in Norway during the mid-19th century, this severe condition usually occurs in people who are immunocompromised, particularly the elderly, disabled or debilitated.
Risks associated with scabies
Scabies can infest any human who comes in contact with the mites, including people in good health. The only known risk factor is direct skin contact with someone who is infested. Good hygiene and health practices cannot prevent transmission if there is close contact with an infected person. The contact one experiences in social or school settings is not likely to be sufficient to transmit the mites. Sexual or other close contact (such as hugging) is required to spread the condition. The condition does appear in clusters, so outbreaks may occur within a given community.
Life cycle of scabies
Scabies is an infestation of the Sarcoptes scabiei mite, also known as the human itch mite.
After burrowing under the skin, the female mite lays its eggs in the tunnel it has created. Once hatched, the larvae move to the surface of the skin and spread across the body or to another host through close physical contact.
Humans are not the only species affected by mites; dogs and cats can also be infected. However, each species hosts a different species of mite, and while humans may experience a mild, transient skin reaction to contact with non-human animal mites, a full-blown human infection with animal mites is rare.
Scabies is highly contagious and spread via direct skin-to-skin contact or by using a towel, bedding, or furniture infested with the mites. As such, some of the most likely people to become infested with mites include:
- Children attending day care or school
- Parents of young children
- Sexually active young adults (and people with multiple sexual partners)
- Residents of extended care facilities
- Older adults
People who are immunocompromised (including those with HIV/AIDS, transplant recipients, and others on immunosuppressant medications)
Itching: This is the main symptom of scabies. This is often severe and tends to be in one place at first (often the hands), and then spreads to other areas. The itch is generally worse at night and after a hot bath. You can itch all over, even with only a few mites, and even in the areas where the mites are not present.
Mite tunnels (burrows): These may be seen on the skin as fine, dark, or silvery lines about 2-10 mm long. They most commonly occur in the loose skin between the fingers (the web spaces), the inner surface of the wrists, and the hands. However, they can occur on any part of the skin. You may not notice the burrows until a rash or itch develops.
Rash: The rash usually appears soon after the itch starts. It is typically a blotchy, lumpy red rash that can appear anywhere on the body. The rash is often most obvious on the inside of the thighs, parts of the tummy (abdomen) and buttocks, armpits, and around the nipples in women. The appearance of the rash is often typical. However, some people develop unusual rashes which may be confused with other skin conditions.
Scratching: Scratching due to intense itching can cause minor skin damage. In some cases the damaged skin becomes infected by other germs (bacteria). This is a secondary skin infection. If skin becomes infected with bacteria it becomes red, inflamed, hot, and tender.
Aggravation of pre-existing skin conditions: Scabies can worsen the symptoms of other skin conditions, particularly itchy skin problems such as eczema, or problems such as psoriasis. Scabies can be more difficult to diagnose in these situations too.
Scabies in hand
Vigorous scratching can break your skin and allow a secondary bacterial infection, such as impetigo, to occur. Impetigo is a superficial infection of the skin that’s caused most often by staph (staphylococci) bacteria or occasionally by strep (streptococci) bacteria.
A more severe form of scabies, called crusted scabies, may affect certain high-risk groups, including:
People with chronic health conditions that weaken the immune system, such as HIV or chronic leukemia
- People who are very ill, such as people in hospitals or nursing facilities
- Older people in nursing homes
- Crusted scabies, also called Norwegian scabies, tends to be crusty and scaly, and to cover large areas of the body. It’s very contagious and can be hard to treat.
Diagnosis and test
Most diagnoses of scabies infestation are made based upon the appearance and distribution of the rash and the presence of burrows. Some common testing methods are:
Microscopic exam of scrapings from suspicious lesions – Scrapings are placed on a slide and examined under a microscope for S. scabiei mites
Burrow Ink Test (BIT) – The suspicious area is rubbed with ink, which is then wiped off. If infestation has occurred, the characteristic zigzag or S pattern of the burrow across the skin will appear.
Topical tetracycline solution – A topical tetracycline solution may be applied to the suspicious area as an alternative to the BIT. The excess solution is wiped off the area with alcohol and examined under a special light to identify the characteristic zigzag or S pattern of the burrow.
Shave biopsy – A fine layer of skin is shaved off at the possible site of infestation and examined under a microscope for evidence of mite infestation.
Needle extraction of mites – A needle is inserted into the length of the burrow and the mite is extracted with the needle and placed on a slide to be examined under a microscope.
The diagnosis of scabies can be especially difficult in elderly persons living in long term care facilities. Their skin is generally dry and scaly and there may be preexisting, chronic dermatological conditions for which oral or topical steroids have been prescribed. Usually, the first indication that a scabies infestation is evolving is complaints of itching and new onset of a rash by one or more residents within a period of 5-12 days.
Exposed health care workers, volunteers and frequent visitors may also complain of itching and rash at about the same time. Skin scrapings, when Georgia Scabies Manual 10 revised: 6/21/12 performed properly, will almost always be positive in persons suspected of having atypical or crusted scabies. However, newly infected persons are more likely to have typical scabies and skin scrapings, even when repeated several time at different sites, may be negative. However, even if a skin scraping or biopsy is negative, it is possible that a person is still infested. Typically, there are fewer than 10-15 mites on the entire body of the infested person, which makes it easy for an infestation to be missed.
Common sites for scabies rash
Scabies can develop anywhere on the skin. The mites, however, prefer to burrow in certain parts of the body. The most common places to have itching and a rash are:
Itching and rash may affect much of the body or be limited to common sites such as:
- Between the fingers
- Shoulder blades
The head, face, neck, palms, and soles often are involved in infants and very young children, but usually not adults and older children.
Common sites for scabies
Treatment and medications
Scabies treatment involves eliminating the infestation with medications. Several creams and lotions are available with a doctor’s prescription. You usually apply the medication over all your body, from your neck down, and leave the medication on for at least eight hours. A second treatment is needed if new burrows and rash appear.
Because scabies spreads so easily, your doctor will likely recommend treatment for all household members and other close contacts, even if they show no signs of scabies infestation.
Medications commonly prescribed for scabies include:
Permethrin cream, 5 percent (Elimite): Permethrin is a topical cream that contains chemicals that kill scabies mites and their eggs. It is generally considered safe for adults, pregnant women, and children ages 2 months and older. This medicine is not recommended for nursing mothers.
Lindane lotion: This medication also a chemical treatment is recommended only for people who can’t tolerate other approved treatments, or for whom other treatments didn’t work. This medication isn’t safe for children younger than age 2 years, women who are pregnant or nursing, the elderly, or anyone who weighs less than 110 pounds (50 kilograms).
Crotamiton (Eurax): This medication is available as a cream or a lotion. It’s applied once a day for two days. This medication isn’t recommended for children or for women who are pregnant or nursing. Frequent treatment failure has been reported with crotamiton.
Ivermectin (Stromectol): Doctors may prescribe this oral medication for people with altered immune systems, for people who have crusted scabies, or for people who don’t respond to the prescription lotions and creams. Ivermectin isn’t recommended for women who are pregnant or nursing, or for children who weigh less than 33 pounds (15 kg).
Although these medications kill the mites promptly, you may find that the itching doesn’t stop entirely for several weeks.
Doctors may prescribe other topical medications, such as sulfur compounded in petrolatum, for people who don’t respond to or can’t use these medications.
To prevent re-infestation and to prevent the mites from spreading to other people, take these steps:
Clean all clothes and linen: Use hot, soapy water to wash all clothing, towels and bedding used within three days before beginning treatment. Dry with high heat. Dry-clean items you can’t wash at home.
Starve the mites: Consider placing items you can’t wash in a sealed plastic bag and leaving it in an out-of-the-way place, such as in your garage, for a couple of weeks. Mites die after a few days without food.