Mange in dogs is one of those words that worries owners more than it needs to, and sometimes less than it should. It is not one disease but a group of skin conditions caused by tiny mites, and the two you are most likely to hear about from a vet in Singapore are demodectic mange and sarcoptic mange. They look similar, yet one is usually not contagious and the other spreads easily, even causing itchy bumps on people.
This guide covers how to tell them apart, who can catch what, and what treatment generally involves. It is general information, not veterinary advice; any dog with patchy hair loss or persistent itching should see a vet.
What Mange Actually Is
Mange is skin disease caused by microscopic mites that live on or in the skin, which is why diagnosis happens at the clinic rather than at home.
The two main culprits are:
- Demodex mites, which live inside hair follicles. Small numbers of them are a normal part of nearly every dog’s skin, passed from mother to puppies in the first days of life.
- Sarcoptes mites, which burrow into the upper layers of skin. They are not a normal resident. A dog only gets them by catching them from another infested animal or a contaminated environment.
That difference in where the mite comes from explains almost everything else about how the two conditions behave.
Demodectic Mange: When Normal Mites Get Out of Hand
Demodectic mange, often shortened to “demodex” or “demodicosis”, happens when the dog’s immune system stops keeping its own follicle mites in check and their numbers explode. Because the mites were already there, this is not really an infection caught from somewhere else. It is an imbalance.
It tends to show up in two broad patterns:
- Localised demodex, usually in puppies and young dogs. You might see one or a few small, roughly circular bald patches, often around the eyes, mouth or front legs. Itch is often mild or absent unless a bacterial infection sets in. Many localised cases settle as the immune system matures; your vet will advise on treatment or monitoring.
- Generalised demodex, where hair loss spreads over large areas or several body regions, or affects the paws. The skin can become red, scaly, greasy and infected. In adult dogs, it can signal an underlying illness that vets may look for.
Some breeds appear more prone to demodex, and there is thought to be an inherited component.
Is demodex contagious? In practical terms, no. A healthy adult dog living with an affected dog is very unlikely to develop the condition, and it does not spread to people or cats in the way scabies does.
Sarcoptic Mange: The Itchy, Contagious One
Sarcoptic mange, also called canine scabies, is caused by a mite that burrows into the skin and lays eggs there. The hallmark is intense itching, often far worse than the visible skin damage would suggest. Dogs may scratch, chew and rub themselves almost constantly, and the itch can disturb their sleep.
Common signs include:
- Itching that starts suddenly and is hard to settle
- Crusty, red skin and hair loss on the ear edges, elbows, hocks (the “ankle” joint of the back leg) and belly
- Secondary infections from all the scratching
Is it contagious? Yes, very. Sarcoptic mites spread through direct contact with an infested dog and, less commonly, through shared bedding, grooming tools or environments. In Singapore, situations that bring many dogs together, such as dog runs, boarding, daycare, group grooming and contact with free-roaming community dogs, are the obvious places to be alert. If one dog in a household has sarcoptic mange, vets usually recommend treating all the dogs in the home at the same time, even those without symptoms.
Can people catch it? The dog scabies mite can cause itchy red bumps on human skin, often on the arms, chest or waist where you hold the dog. It does not normally complete its life cycle on people, so the rash tends to fade once the dog is treated, but anyone in the household with a persistent itchy rash should see a doctor or polyclinic and mention the dog’s diagnosis.
Demodectic vs Sarcoptic Mange at a Glance
| Feature | Demodectic mange | Sarcoptic mange |
|---|---|---|
| Where the mite lives | Inside hair follicles, normally present in small numbers | Burrows in the upper skin, not a normal resident |
| Main cause | Immune system not keeping mites in check | Catching mites from another animal or environment |
| Itchiness | Often mild unless infected | Usually intense and constant |
| Typical areas | Face, around eyes, legs, paws, or widespread | Ear edges, elbows, hocks, belly |
| Contagious to other dogs | Not in practical terms | Yes, highly |
| Can affect people | No | Can cause a temporary itchy rash |
| Commonly affected | Puppies, young dogs, immune-compromised adults | Any dog with exposure |
How Vets Diagnose Mange
Because allergies, fungal infections such as ringworm, bacterial skin infections and hormonal problems can all cause similar signs, your vet will want to confirm what is going on before treating. Typical steps include:
- Skin scrapings, where the vet gently scrapes the skin surface and looks at the material under a microscope. Demodex mites are usually found fairly easily this way.
- Hair plucks or tape tests, which can also show demodex mites in follicles.
- Repeated or deeper testing, because sarcoptic mites are notoriously hard to find. A negative scraping does not rule out scabies.
- Trial treatment, where a vet strongly suspects sarcoptic mange from the history and itch pattern and treats it to see whether the dog improves.
Tell your vet when the signs started, whether other pets or people at home are itchy, and about recent boarding, grooming or dog run visits.
Treatment and Recovery
Treatment is prescription-based and decided by your vet, so this section explains the general approach rather than specific products or doses. Never use livestock products, human scabies creams or home remedies without veterinary guidance, as some anti-parasite ingredients are toxic to certain dogs and breeds.
In general, treatment may involve:
- Prescription anti-parasite medication, often given as a chewable tablet or spot-on. Your vet will choose one to suit your dog’s age, weight, breed and health.
- Medicated baths or shampoos to remove crusts and calm the skin, if your vet recommends them.
- Antibiotics or antifungals if there is a secondary skin infection.
- Follow-up visits with repeat skin tests. For generalised demodex, vets usually continue treatment until tests are negative more than once, which can take weeks to months.
At home, you can help recovery by:
- Washing bedding, blankets and soft toys in hot water and drying them thoroughly, especially for sarcoptic mange
- Keeping a dog with sarcoptic mange away from dog runs, daycare and other dogs until your vet says it is no longer contagious
- Feeding a balanced diet that supports skin health; our guide to feeding your dog in Singapore covers the basics
- Telling your groomer about the diagnosis so they can take precautions, and checking with your vet before resuming regular dog grooming
Singapore’s humidity can worsen secondary infections, so keep the coat dry and do not skip follow-ups just because hair is regrowing.
Lowering the Risk
You cannot completely prevent demodex, since it depends on the dog’s own immune system, but you can lower the chances of sarcoptic mange and catch both early:
- Keep up a vet-recommended parasite prevention routine, as some broad-spectrum products also protect against mites
- Check your dog’s ears, elbows and belly regularly, especially after boarding or group play
- Keep up with health checks and vaccinations for dogs, since an overall healthy dog copes better with skin problems
If your dog suddenly starts scratching non-stop or develops bald, crusty patches, book a vet visit sooner rather than later. Both types of mange in dogs respond well to treatment when they are diagnosed properly, and most dogs go back to a full, comfortable coat.
Explore more: Socialising Your Dog in Singapore
Further reading: Scabies in Adults: Symptoms, Treatment and Stopping the Spread