Pet Health
Sarcoptic Mange (Scabies) on Dogs: Symptoms, Causes, and Treatments
Sarcoptic mange or scabies in dogs is a progressive, parasitic skin disease caused by the mite Sarcoptes scabiei. The microscopic Sarcoptes mites burrow holes and live beneath the epidermis of the dog’s skin as parasites.
Intense itching and hair loss are telltale signs of sarcoptic mange in dogs. Other signs include skin lesions, reduced appetite, lethargy, low energy levels, and fever.
Scabies are contagious, and infected dogs spread the issue to healthy dogs and humans. Puppies, elderly dogs, chronically ill canines, and dogs with compromised immune systems are at higher risk of contracting Sarcoptex mites.
Veterinarians diagnose scabies in dogs through skin scrapes. The treatment of sarcoptic mange in dogs is based on antiparasitics and symptom relief.
What are the Signs and Symptoms of Sarcoptic Mange in Dogs?
The signs and symptoms of sarcoptic mange in dogs are listed below.
- Intense Itching: Intense itching is the hallmark of scabies in dogs. The itching irritates the skin and disrupts the dog’s daily activities. Dogs with Sarcoptic mange awaken and stop eating to scratch, bite, or rub their wounds.
- Hair Loss: A common symptom of mange is hair loss, medically termed alopecia. Alopecia is sporadic, affecting specific regions of the body, or generalized.
- Excoriations: Excoriations are self-inflicted wounds caused by the dog’s compulsive scratching. The excoriations are superficial or deep depending on the scratching duration and are prone to secondary bacterial and fungal infections.
- Papules: Papules are raised skin bumps with a diameter smaller than one centimeter. These blemishes are present all over the body but are usually concentrated in the chest area.
- Skin Thickening: Crusty skin thickening appears on hairless regions, such as ear margins, armpits, groins, belly, and ankles.
- Oozing Skin and Crusts: The skin lesions ooze or weep fluids. The secretions dry, forming crusts. Oozing and crusty skin give the dog an unkempt appearance.
- Depression: The skin lesions and itchiness make the dog disinterested in daily activities. Depressed dogs prefer to sleep and have low energy levels.
- Reduced Appetite: The discomfort and itchiness affect the dog’s appetite, leaving it reluctant to eat. Reduced appetite is more common in dogs with secondary bacterial skin infections.
- Weight Loss: The reduced appetite and the high amount of energy spent on constant scratching cause weight loss in some cases.
- Fever: Fever or increased body temperature occurs in dogs with advanced forms of secondary bacterial and fungal skin infections.
- Enlarged Lymph Nodes: Generalized infection associated with scabies and secondary complications cause enlarged lymph nodes in some dogs.
- Changes in Behavior: The constant itchiness alters the dog’s behavior and causes anxiety. Irritability and frequent mood swings are typical.
How do Dogs Get Sarcoptic Mange?
Dogs get sarcoptic mange in the ways listed below.
- Infected Animals: The most common transmission mode is from one dog to another. Infected dogs spread the Sarcoptes scabiei mites into the environment and pass them to other healthy dogs. Wolves, coyotes, and foxes are prominent mite carriers in the wild.
- Fomites: Fomites refer to objects and materials likely to carry an infection. They are one of the five main routes of microorganism transmission. Common fomites for Sarcoptes mites are bedding, dog clothes, and grooming tools.
- High-Density Areas: Sarcoptes mites are heavily present in certain areas, such as dog parks, shelters, doggy daycares, pet grooming saloons, and the wild. Owners asking, “How do dogs get mange?” must consider whether they frequented a high-risk area.
- Underlying Health Issues: Dogs with underlying conditions, like weak immunity, are at higher risk of getting sarcoptic mange. Puppies and older dogs with chronic health issues are predisposed.
- Breed Risk: Labradors, Cocker Spaniels, and Doberman Pinschers appear to be prone to scabies, according to a report titled “Canine Scabies: An Update” by WSAVA in 2004.
How is Sarcoptic Mange Diagnosed in Dogs by Veterinarians?
Sarcoptic mange is diagnosed by veterinarians based on clinical symptoms and skin-scraping examination results. Vets suspect mange in young puppies and older, sick dogs with sudden onset of itching, hair loss, and skin lesions.
The standard test for sarcoptic mange is skin scraping. The vet uses a scalpel blade to scrape the skin's surface, and the scraping must be deep enough to irritate.
The sample is analyzed under a microscope. The presence of mites confirms the diagnosis, but the absence of mites does not rule out mange. Mites are able to burrow deep into the skin and are difficult to determine in a superficial skin scraping.
Tests, such as fecal flotation, PCR, and skin biopsy, are performed to rule out other problems with similar clinical signs, including atopic dermatitis and dog allergies.
Canine scabies “requires prompt diagnosis and treatment to maintain dog welfare,” according to a study, “Diagnosis and Treatment of Canine Scabies,” published in the Journal In Practice in 1998.
How does sarcoptic Mange Differ from Demodex Mange in Dogs?
Sarcoptic mange differs from Demodex mange in dogs in that it is contagious. Demodex in dogs is not contagious and does not spread from infected to healthy canines.
The two other differences between Sarcoptic and Demodex mange are the mite habitat and clinical signs. Sarcoptic mites live in tunnels they create under the skin, while Demodex mites live inside hair follicles and oil glands.
The main symptom of Sarcoptic mange is intense itching, while Demodex mange on dogs does not cause itchiness.
Is Sarcoptic Mange Contagious to Other Dogs or Humans?
Yes, sarcoptic mange is contagious to other dogs and humans. “Canine sarcoptic mange is a highly contagious skin disease,” reports a study, “Canine Sarcoptic Mange (Sarcoptic Acariasis, Canine Scabies),” issued in Companion Animal in 2012.
Dogs carrying Sarcoptic mites are contagious for 36 hours after initiating treatment, and the living environment is properly decontaminated.
Pet owners asking, “Is mange contagious to people?” must know the answer is yes. Sarcoptic mange is a zoonotic disease that spreads from dogs to humans.
Sarcoptic mange is “transmitted to humans through contact with infected animals,” states a study, “Canine Scabies: A Zoonotic Ectoparasitic Skin Disease,” published in the International Journal of Current Microbiology and Applied Sciences in 2017.
What is the Treatment for Sarcoptic Mange in Dogs?
The treatment for sarcoptic mange in dogs is listed below.
- Topical Antiparasitics: Popular topical antiparasitics are fipronil and amitraz. “Amitraz effectively treats canine scabies in 97.8% of dogs after a single treatment,” according to a study “Clinical Evaluation of Amitraz for Treatment of Canine Scabies” issued in Modern Veterinary Practice in 1984.
- Systemic Antiparasitics: The licensed medication for dog scabies is selamectin, which is used as a spot-on liquid. “Selamectin effectively reduces naturally acquired Sarcoptes scabiei infestations in dogs by over 93% and 100%,” reports a study “The Efficacy of Selamectin in the Treatment of Naturally Acquired Infestations of Sarcoptes Scabiei on Dogs” published in Veterinary Parasitology in 2000. Other systemic antiparasitics are ivermectin (injectable), milbemycin oxime (orally), and moxidectin (oral or injectable).
- Antibiotics or Antifungals: Antibiotics or antifungals are prescribed to dogs with advanced secondary bacterial or fungal skin infections. The exact type of antimicrobial and length of treatment varies based on the type of germ and infection severity.
- Anti-Inflammatories or Steroids: Oral anti-inflammatories or corticosteroids are administered to dogs with severe skin infections to reduce itchiness and inflammation.
- Antiseptic Shampoos: Antiseptic shampoos are applied before the antiparasitic solution. The main goal of shampooing is to cleanse the skin and help the sores heal faster.
- Environmental Decontamination: Washing the dog’s bedding, blankets, grooming tools, and other belongings kills live mites on the surface. Sarcoptes mites remain active without a host for 36 hours, but cleaning speeds up the decomposition process.
How Does Sarcoptic Mange Affect a Dog's Immunity?
Sarcoptic mange does not directly affect the dog’s immunity. Scabies causes intense itching in dogs. Intense itchiness triggers anxiety.
Anxiety is associated with a weakened immune system in dogs, reports a study, “Psychogenic Stress in Hospitalized Dogs: Cross-Species Comparisons, Implications for Health Care, and the Challenges of Evaluation,” published in Animals in 2014.
Anxiety supports the production of the hormone cortisol in the body, which lowers dog immunity. A weak immune system is unable to fight off infections and diseases.
How do Dogs Contract Sarcoptic Mange?
Dogs contract sarcoptic mange from other infected dogs or the environment. Dog-to-dog contraction is the most common means of transmission.
The Sarcoptes mite survives in the environment without a host for up to 36 hours. Mites are parasites of opportunity and attach to hosts when the opportunity presents itself.
Dogs contract sarcoptic mange from infested bedding and grooming supplies. Mites are heavily present in locations frequented by wild hosts, like foxes and wolves.
Can Humans Contract Sarcoptic Mange from Infected Dogs?
Yes, humans can contract sarcoptic mange from infected dogs. Scabies is defined as a zoonosis and is dangerous to humans.
“Canine scabies can be transmitted to humans through contact with dogs,” explains a study “Canine scabies in dogs and in humans” published in JAMA in 1967.
Humans who contract sarcoptic mange from infected dogs develop a pimple-like skin rash and intense itchiness. Medical attention is advisable to manage the symptoms.
What are the Early-Stage Symptoms of Mild Sarcoptic Mange in Dogs?
The early-stage symptoms of mild sarcoptic mange in dogs are itchiness and hair loss. Mild cases are marked by localized infection, and the symptoms are limited to a specific area.
Itchiness is the first symptom, and the dog becomes obsessed with licking, scratching, biting, or rubbing itself against surfaces. The itching progresses, causing patchy hair loss in the affected area.
Sarcoptic mange in dogs is hard to differentiate from other skin conditions in the early stages. See a veterinarian if the dog is suddenly itchy and losing its coat.
How Can You Treat Sarcoptic Mange in Dogs with Topical Medications?
You can treat Sarcoptic Mange in Dogs with topical medications by following the steps listed below.
- Clip the Dog’s Coat. The first step in dogs with severe infections is clipping. Clipping refers to cutting the dog’s coat to a certain length with grooming clippers. Less hair allows the topical treatment to penetrate the dog’s skin more efficiently.
- Bathe the Dog in a Chemical Solution. Dips, or short-lasting baths, are done with amitraz (0.025 to 0.05%) and lime sulfur. Amitraz is not recommended for diabetic pets/owners, young puppies, nursing bitches, and Chihuahuas, while lime sulfur is unavailable in Europe, stains, and has an unpleasant scent. Newer treatment options make dips a messy and often unnecessary step in treating scabies.
- Apply Fipronil on the Skin. Use fipronil (a 0.25% solution) on pets sensitive to amitraz, primarily puppies under three months old and nursing bitches. Fipronil is a broad-spectrum insecticide that attacks the mites’ nervous systems.
- Administer Selamectin. Selamectin is explicitly formulated for treating scabies in dogs and is applied as a spot-on. Selamectin comes in various potencies for dogs of different sizes and is available at the vet’s office.
- Treat All Pets in the Living Space. Pet owners asking “how do dogs get mange?” must use topical or systemic antiparasitics on all other pets living in the same household with the affected dog. Repeat the treatments every few weeks, as the product’s manufacturer suggested.
Are Mange Mites Visible on Dogs?
No, mange mites are not visible on dogs. The Sarcoptes scabiei mite is minuscule (0.2 to 0.4 mm long), white, and circular.
Sarcoptes mites prefer skin regions with sparse hair. Predilection places are the edges of the ears, belly, armpits, groins, elbows, and knees.
Adult Sarcoptes mites mate on the surface of the skin. The females, after mating, burrow deep into the skin and lay their eggs.
The hatched eggs or larvae emerge to the surface to feed on skin cells and lymph, where they mature into nymphs. The complete life cycle lasts around three weeks.
Mange mites are not visible on dogs because they are tiny and live under the skin. The clinical signs of mites are an indicator of their presence.