Demodex is a normal, microscopic (can’t be seen with the naked eye) mite that lives deep in the hair follicles of dogs. Usually Demodex mites do not cause disease but in some dogs, usually puppies, or sometimes older debilitated dogs, they can cause hair loss and skin irritation. Staffordshire Bull Terriers can be commonly affected. Typically hair loss is patchy, and affects the face and paws but in severe cases it can become generalised. Dogs can also develop secondary bacterial infections, seen as spots, redness, and crusting. Sometimes a darkening of the skin tone may be noted and is more often seen if the case has been going on for a while. Rarely, severely affected dogs can become painful, feverish and lethargic and need urgent veterinary attention. Demodectic mange is not contagious to other animals or to humans.
Demodex mange is usually easily diagnosed. Your vet will take multiple deep skin scrapes or hair samples and examine them under the microscope. Don’t worry though, this doesn’t hurt. They may also want to take further skin samples to evaluate for secondary bacterial skin infection.
Demodectic mange in young dogs is now usually easily treated with prescription anti-parasitic agents which are usually easy-to-administer tablets. Sometimes medicated weekly dips are used instead. Spot-on treatments can also be used and it’s important to talk to the vet about which option is best for you and your pet. Many young dogs will also naturally improve with increasing age as their immune system matures. You may find your dog needs additional treatment with medicated antibacterial shampoos, or even a course of antibiotics, if they have bacterial skin infections. If your dog is older when the diagnosis is made, your vet may recommend further testing such as blood and urine samples to investigate for any underlying conditions that may have allowed the mites to get out of control. This may feel at first a bit over the top, you only went in with a skin problem! Give your vet a big thumbs up though, they’re doing a brilliant job and trying to get to the bottom of the problem, not just looking at the tip of the iceberg. Demodectic mange in older dogs can be a lot trickier to treat, so it may take longer to get under control and that is very normal.
As there appears to be a genetic predisposition to demodectic mange it is recommended by veterinary dermatologists (skin specialists) that dogs who have had Demodex are not bred from, to try and prevent the genes that are associated with this condition from being passed on to their offspring.
The hormonal changes associated with seasons in female dogs can exacerbate demodectic mange or lead to relapse, so neutering of affected females is also advised.