Ear infections in dogs are, unfortunately, quite common. Some dogs are especially prone to them due to the shape of their ears. Long, floppy, or furry ears are more likely to become infected. Or, your dog may have a medical condition that predisposes them to infections.
What Causes Ear Infections in Dogs?
Your dog's ear infection can be caused by yeast, bacteria, or parasites. Yeast infections are the most common, and these are generally not contagious between dogs--phew! Bacterial infections are also not generally contagious, however, ear infections caused by parasites like mites are contagious and can transmit between dogs and other animals. Unfortunately, even pet owners can be affected by some parasites!
Most dogs get ear infections because of an overgrowth of yeast in their ears. All dogs and animals have yeast organisms living on the surface of the skin, and a certain amount is normal and not harmful. However, if the yeast overgrows it can cause infection in your dog's ears, resulting in discharge and sores in the ear. This usually occurs due to a disruption in pH such as when antibiotics are administered, the immune system is compromised, or another disease is present. Dogs that have reduced air flow to the ears are particularly susceptible, as warm, moist conditions favor yeast growth.
Although yeast infections of the ear aren't contagious between dogs, they can develop into bacterial infections or make your dog susceptible to other fungal and parasitic infections, which may be contagious. Skin conditions or a compromised immune system can predispose your dog to fungal infections, such as ringworm, that can be transmitted between animals, and even to people. It is advisable to treat yeast infections, and take precautions to prevent contamination by wearing gloves and cleaning bedding in case secondary infections are developing or are present. Verify the infection occurring with a veterinarian, as many skin conditions and infections look like a common yeast infection but require a different type of treatment. Your veterinarian can prescribe appropriate treatment with oral or topical antifungal medication that will kill excess yeast organisms. You will also need to clean your dog's ears to remove dead yeast cells and allow healing of the ear.
Yeast infections are not contagious, rather are due to your dog's own microflora getting out of control. Factors that may contribute to this are:
Lack of airflow to ears, a warm moist environment due to long, floppy, furry ears
Dirty ears with wax or debris buildup
Abnormal ear structures that do not allow normal ventilation or “hold” yeasts in place where they can accumulate
Moist or wet conditions, such as occur when there is high humidity or the dog has been swimming
Allergies, reactions or side effects from medications
Disease or medical conditions, especially endocrine or immune system disorders
Sometimes parasites, such as mites, invade your dog's ears. Infection caused by parasites is contagious between dogs, and may also contribute to the formation of yeast or bacterial infections in their ears. Mites can also affect other pets and pet owners, so you will want to treat mite and other parasitic infections ASAP to prevent them from spreading to other animals or yourself.
Check with Your Vet
Your veterinarian can identify the source of your dog's ear infection and prescribe appropriate medication. Usually, medication is topical and consists of antibiotic, antifungal or antiparasitic treatment. But if infection is rampant, systemic oral medication may also be prescribed. In addition, thorough cleaning of your dog’s ears is necessary to remove debris, ensure medication gets to skin surfaces, and establish airflow to the skin. This will require some diligence in ear cleaning on the part of pet owners, but is well worth it, to allow medication to be effective and resolve the ear infection.
Prevention and Intervention
Ear infections in dogs are quite common and usually not contagious, unless “helped” along by a parasite that is contagious. Many factors contribute to the development of yeast infections in dogs, and steps to prevent these conditions will reduce the incidence of ear infections for your dog. Fortunately, yeast infections are treatable with medication and rigorous cleaning of the ears. Parasites, such as ear mites, can be transmitted between animals, and may contribute to ear infections, so addressing parasitic infections quickly before you, or other pets are affected, is advised. A veterinarian's care is recommended to adequately diagnose the source of the ear infection, fungal, bacterial or parasitic, and receive the appropriate medication.