Skin Conditions in Dogs: Are They contagious?

Skin Conditions in Dogs.  Are They contagious?  Did I give it to my dog or vice versa….Help!

There are a few diseases that are, in fact, contagious between your family pet and other household members.  That said, that is a lot of misinformation and misconceptions among pet owners.  Let’s focus on a few of those diseases that are frequently questioned.

 IS IT MANGE (scabies)?  How a dermatologist treats scabies mites.

There are several types of mange or mite infestation in animals.  Sarcoptes scabiei mites (scabies, mange) are very itchy and highly contagious.  The mite is microscopic.  You cannot see it with the naked eye. It can affect a wide range of species:  dogs, rarely cats, rabbits, foxes, guinea pigs, ferrets, sheep, goats, cattle, pigs, and humans.  Very often, affected animals have visited areas where large populations of animals are present; dog parks, grooming parlors, shelters, kennels, pet stores, training facilities, etc.  Currently, epidemics are being recognized in fox-dense regions of the country.  Some of these patients are misdiagnosed as allergic and can even test “false positive” on allergy tests due to an antigenic cross-reactivity of the scabies mite and house dust mites (a common allergen in animals and humans). 

Affected dogs will often have crusting of the margins of the pinna (ear flaps) and the elbows.  These pets are extremely uncomfortable and may even be non-responsive to most medications used to control itching. 

The mites can be found on skin scrapings taken by your veterinarian.  Luckily, treatment is typically rapid with appropriate parasiticides.  Sometimes, if mites are not found but the clinical evidence is dramatic, your pet may be placed on parasiticides as a therapeutic trial.  Affected animals should be isolated from others during therapy to prevent contagion.  Treatment will encompass 4-6 weeks to make sure the “life cycle” of the mite is controlled. 

If any zoonosis (spread to human family members) is present, not to worry, there are very effective and quite luxurious creams that rid you of the problem promptly.  Contact your physician and they can prescribe an appropriate permethrin cream.  It is not always necessary to decontaminate the household since the mite does not like to live off of a host.  In extreme infestations or where the humans in the household are being affected, it is recommended to exterminate the house “as if” for fleas.   

 My dog has a rash!  Is it poison ivy?

Probably not…. your dog’s rash is probably a bacterial infection (pyoderma or folliculitis). Dogs are typically not susceptible to poison ivy or poison oak. Although you can develop poison ivy & poison oak from your pet if  the oils from these plants are on the coat of your pet! 

Pyoderma is a very common problem in the dog and it is usually caused by Staph. bacteria.  This infection is typically recurrent (as often occurs in eczema patients) so it is really important to identify and treat underlying causes to help prevent relapses. A veterinary dermatologist can help pinpoint the cause. Allergy (atopic dermatitis, flea allergy, food allergy) is the most common cause but other diseases that compromise your pet’s the immune system can also contribute. Some common causes:  allergy (most common), parasites, hormonal disorders, and hair follicle disorders

What does a bacterial skin infection look like in my dog?

These are the typical stages of progression in a bacterial folliculitis:

·      Red inflamed skin, small pink “pimples”- these are early lesions

·      Pustules  (similar to acne in people)

·      Crusts/ scabs

·      “Epidermal collarette”: circular areas of scale with hair loss or redness at the center (often mistaken for ringworm due to the circular appearance)

·      Pigmented spots (this can often mean the lesions are healing!)- resolving lesions

Topical therapy alone (dog shampoos & sprays) can be effective in milder cases or can be a great form of prevention.   Make sure to choose a product that has proven antibacterial ingredients.  Many products make false claims of efficacy.  Ask you veterinarian for specific choices for your dog.

I have a recurrent skin infection.  Is my pet the cause?? 

Actually…. People pose a higher risk for the pets!

There are some bacterial pathogens that CAN be contagious between pets and their humans.  These conditions are termed “zoonotic”.  Sometimes, when people have recurrent bacterial infections, the pets are blamed as a likely source.  This is typically NOT the case!  The Infectious Disease Society of America advises testing other human contacts as a source of contagion…..not the household pets.

Strep throat:  This false accusation is particularly true when someone is prone to recurrent Strep (Streptococcus pyogenes) throat episodes.  Some physicians will point the finger at the family pet.  Recent studies have shown that there is NO evidence that dogs and cats are a reasonable source for these infections.

MRSAMethicillin resistant Staphylococcus aureus is a “super-bug” that has been problematic in the human population for years.  The bacteria is resistant to a large number of typically used antibiotics, making treatment quite difficult.  People and animals with compromised immune systems from disease or drugs, skin wounds, or surgical sites are most susceptible to this organism.  People are the reservoir….not animals. 

scanning electron photomicrograph of Staph baceria

 

MRSPMethicillin resistant Staphylococcus pseudintermedius is the multi-drug resistant form of staph that is more common in dogs.  This form is must less zoonotic and unlikely to evolve as a problem in people.  MRSP infection is rare in people.  Simple precautions to avoid contagion in “high-risk” people would be:

 1.  Avoid direct contact with the pet’s mouth, nose or infected sites

 2.  Wash animal bites or scratches immediately

 3. Good hand washing technique at all times

 4.  Keep wounds and skin covered

Staph infection on the skin of  a dog

 

Reliable sources of information on the web:

1.  wormsandgermsblog.com

2.  cfsph.iastate.edu/Zoonoses/index.php

UNLEASH YOUR DOG’S HEALTHY SKIN