Bacterial Skin Infection in Dogs: Pyodermas – a common condition

Bacterial skin infections in dogs are common and often secondary to another condition—such as allergic skin disease. Regardless of the cause, these infections require treatment as they are painful, and can spread both outward along the skin and deeper into the tissues. 

Depending on the location and extent of infection, the condition may appear in different forms, classified by depth: 

Dog skin infection causes are many and varied, let’s discuss the bacteria causing it and the main causes of infections.  

Underlying conditions to skin infections 

Bacterial skin infections can often develop due to an underlying condition that causes the skin to become more fragile. Various skin conditions, as well as immunologic or metabolic disorders, can predispose individuals to secondary skin infections. An example of this would be in a dog that suffers from allergic skin disease; allergic skin disease, regardless of what the dog is allergic to, is incredibly itchy that can lead to skin trauma and thus infection. In addition, their skin microbiota is modified and more prone to let bad bacteria overgrow.  Certain breeds may be more susceptible to bacterial infections as they are predisposed to certain underlying conditions, for example in the case of breeds predisposed to developing allergies, Labrador Retrievers, Shar Peis, Boxers, Boston Terriers, and Westies are amongst the breeds more likely to be affected.  

Is dog bacterial skin infection contagious?

Almost never! Staph and other skin infections in dogs are usually the result of a disruption in that natural microbial barrier and involve the same bacteria that are present on every dog’s skin. So, in most cases, there is no risk of it being passed from dog to dog. The risk of transmission of Staph from a dog to a human is low and is even less likely when good hand hygiene is practiced after treating or touching affected areas. Nonetheless, transmission from dogs to humans can occur in rare cases, particularly in individuals with compromised immune systems such as infants, older adults, or those undergoing chemotherapy. Practicing thorough hand hygiene after contact with affected areas significantly reduces the risk of transmission. 

It’s important to remember, though, that even though Staphylococcus bacteria in dogs are similar to those in humans, the possibility of transmitting genes for antibiotic resistance is real. 

Your vet will perform a clinical exam and may run tests (e.g., cytology, cultures) to identify the bacteria and determine the best treatment. As infections are often secondary, follow-up may be needed to identify underlying conditions once the skin has healed. 

1 : Suppress bacterial growth on, into and below the skin

The skin provides the reservoir of bacteria which are causing the problem. Therefore, suppressing growth - especially of the pathogenic or disease-causing organisms - is important. Approach will depend on the severity of the imbalance. Common approaches involve the use of antiseptic agents such as chlorhexidine* digluconate (as in DOUXO® S3 PYO), except for deep pyodermas. An initial shampoo allows to remove bacteria, crusts, etc. while subsequent use of the mousse allow the ingredient a longer direct skin contact for an optimal performance. For more localized cases, pads allows to bring antiseptic ingredients only where necessary. By knocking down
the bacterial population, we create a “breathing space” for healing to occur.  

In case of deep pyoderma or refractory cases, vets will usually prescribe antibiotic medications. In most cases, these will be a long course – generally at least 3-4 weeks for refractory pyoderma and as long as 10 weeks for deep pyoderma. It is therefore essential that the most appropriate antibiotic is chosen, based on cultures, to reduce the further development of resistance, and to effectively treat resistant bacteria.  

2: Relieve the pain, itching and inflammation 

In many cases, self-trauma or self-injury is part of the problem, due to the pain, itchiness and discomfort of the infection. Products containing Ophytrium® such as DOUXO® S3 PYO (to combine with beneficial effects of chlorhexidine* against bacteria) are beneficial to soothe irritated skin. 

3: Restore the natural skin barriers

In case of such disorders, bacteria have damaged or overcome the microbial and mechanical barriers. Reinforcing and restoring these are an important part of treatment. Reducing surface bacteria is an important first step; however, ingredients such as Ophytrium® (included in the DOUXO® S3 PYO formulation) also help support the skin’s mechanical barrier and limit bacterial adhesion and biofilm formation, while restoring the balance of the protective microbial flora for healthy skin. 

4: Treat or manage any underlying causes

Skin dysbiosis rarely occurs on its own out of the blue - there is usually a trigger cause, if not an underlying disease process. Identifying that and managing or eliminating it is essential if repeat infections are to be avoided once treatment has finished! 

What is the prognosis and is it possible to prevent?

The prognosis for bacterial skin infection is generally good, even if recovery can be long if the infection is deep. Avoidance of
relapse can require long-term management of the underlying cause. If the underlying condition has been controlled, then the secondary or recurrent bacterial infections are reduced.  

Prevention will depend on the cause. Long-term management of allergies, up-to-date parasiticide treatment, maintenance of a healthy coat are several measures that may prevent future flare-up.