Pyoderma (Staph Skin Infection) in Dogs

Types of Pyoderma

• Surface pyoderma: infection on the skin surface, including hot spots and skin-fold infections. Skin-fold dermatitis is most common in English Bulldogs, French Bulldogs and Pugs.^2,13
• Superficial pyoderma: infection of the hair follicles (superficial bacterial folliculitis), the most common form. Puppy pyoderma (impetigo) causes pustules on the hairless belly of young dogs.^4,2,5
• Deep pyoderma: infection below the follicles, with pain, swelling, crusts and draining tracts. It's more serious and needs prompt treatment.^5,1

What Causes Pyoderma?

Staph bacteria live on normal dog skin and cause infection when the skin's defenses break down.^5,2 Common triggers include:

• Allergies (atopic dermatitis, food allergy, flea allergy)^14,1
• Fleas and mites^1,2
• Hypothyroidism and Cushing's disease^1,5
• Skin folds, pressure points such as elbows, and poor grooming¹
• Steroid medicines and incomplete treatment courses, which are linked to repeat infections^1,5

Symptoms

• Red bumps and pustules, usually around hair follicles⁴
• Crusts, scale and rings of peeling skin (epidermal collarettes)^4,1
• Patchy, "moth-eaten" hair loss, and welts that look like hives in short-haired breeds^4,1
• In deep pyoderma: "pain, crusting, odor, and secretions of blood and pus"¹

Diagnosis

Your vet will examine the skin and take cytology samples to confirm bacteria are present before using antibiotics.^6,2 A bacterial culture and sensitivity test is recommended for deep infections, for infections that don't improve, for dogs with recent or repeated antibiotic use or resistant infections, and whenever antibiotic pills are planned.^2,6,7 Your vet will also look for the underlying cause, such as skin scrapings for mites, allergy workups and hormone tests.^2,5

Treatment

• Surface and superficial pyoderma: chlorhexidine (2 to 4%) shampoos, wipes or sprays are the first choice, usually without antibiotic pills.^2,9,15
• When pills are needed: for deep pyoderma, when topical treatment isn't possible, or when topical treatment hasn't worked after 2 weeks. Vets choose from first-line antibiotic classes, ideally guided by a culture.^6,9
• How long: superficial infections are rechecked after about 2 weeks and deep infections after about 3 weeks. Treatment stops when the skin and cytology are clear, and courses longer than 6 weeks are rarely needed.⁶
• Hot spots and skin-fold infections: cleaning, antiseptics and sometimes a short anti-inflammatory medicine.^9,2
• The underlying cause must be treated, or the infection "will inevitably come back."⁹

Older advice to continue antibiotics for a week after the skin looks normal comes from 2014 guidelines and has been replaced.^4,6 Always follow your vet's instructions on how long to treat.

Resistant Staph (MRSP)

Methicillin-resistant Staphylococcus pseudintermedius (MRSP) resists many common antibiotics. It isn't more aggressive than ordinary staph, but treatment options are fewer.⁷ Risk factors include past antibiotics, past resistant infections, recent hospital stays and living with a pet or person who had one.^7,16 Topical chlorhexidine works against MRSP, and topical treatment can be the only treatment needed for surface and superficial MRSP infections.^7,10

Can People Catch It?

Pyoderma itself isn't considered contagious in the usual sense, and dog staph rarely infects people.⁷ It can, however, pass to owners. A 2023 review found that about 4 to 6% of dog owners and vets carried it, and rare human infections are often misidentified as S. aureus.⁸ Wash your hands after touching infected skin, especially if anyone in the home has a weak immune system.^7,8

Preventing Repeat Infections

• Control allergies, fleas and other underlying causes.^6,1
• Ask your vet about regular antiseptic bathing for dogs that keep getting infections.⁶
• Keep skin folds clean and dry, and keep up with grooming.¹
• Give the full treatment your vet recommends, and go to rechecks.^6,1

Frequently Asked Questions

Is pyoderma in dogs serious?

Superficial pyoderma is common and treatable. Deep pyoderma is more serious and can be painful.

How long does pyoderma take to clear up?

Superficial cases are usually rechecked after 2 weeks of treatment; deep cases take longer.

Is dog staph contagious to humans?

Rarely. It can pass to owners, so wash your hands after touching infected skin.

What can I put on my dog's staph infection?

Chlorhexidine shampoos, wipes or sprays are usually first choice. Ask your vet before using any cream.

Why does my dog keep getting staph infections?

Usually because an underlying problem, such as allergies, hasn't been fully controlled.