What Are Skin Infections in Dogs?
Skin infections in dogs occur due to infectious agents such as bacteria, fungi, or parasites. These infections can affect all areas of the skin, including the ears, nose, hair, and nails. The severity of the infection depends on its type, ranging from mild to painful and itchy. Some infections are contagious and can spread through direct contact or the environment, while others are caused by organisms that naturally reside on the skin and are not considered contagious.
Types of Skin Infections in Dogs
Skin infections in dogs can be classified into four main types: bacterial, fungal, parasitic, and viral.
Symptoms
- Redness
- Bumps or raised areas of the skin
- Itchiness, often evidenced by scratching, licking, and/or chewing the skin
- Scales or flakes
- Crusts or scabs
- Hair loss, known as alopecia
- Oozing or discharge, which may be blood, pus, or clear fluid
- Changes in skin color, such as becoming darker or lighter
Causes
Skin infections in dogs have various causes. Some infections are primary, directly resulting from infectious organisms. Others are secondary, stemming from an underlying disease process that prompts the infection to occur.
Primary Infection
An example of a primary parasitic skin infection is scabies. Dogs contract scabies through direct contact with an infected animal. The scabies mite subsequently induces the clinical signs associated with the disease. Ringworm serves as an example of a primary fungal infection, acquired through contact with infected individuals or contaminated environments, including soil.
Secondary Infection
A prevalent instance of a secondary skin infection arises from skin allergies. These allergies trigger skin inflammation, creating a conducive environment for organism proliferation. Consequently, bacteria or fungi that typically inhabit the skin proliferate, resulting in bacterial or fungal skin infections.
Diagnose
Veterinarians employ various basic skin tests to diagnose a majority of skin infections in dogs. Among the most common tests are:
- Skin scrapes: Utilizing a dull scalpel blade, the top layer of the skin is scraped to detect skin parasites like demodex.
- Skin cytology: Samples are collected by pressing a microscope slide directly against the skin lesion or via a needle and syringe. The samples are then examined under the microscope for bacteria, fungi, or abnormal skin cells.
- Tape preps: Clear tape is used to gather a sample of hair or skin, which is examined under the microscope to identify bacteria, fungi, or parasites.
- Cotton swabs: Samples are collected, often from inside the ear, using a cotton swab to diagnose bacterial, fungal, or parasitic infections.
- Cultures: Skin, hair, or discharge samples are collected onto a growth plate to detect bacterial or fungal growth over time. This test also helps determine the most effective antimicrobial medication to treat the infection.
Treatment
The treatment approach for a skin infection in dogs varies depending on the type of infection, its location, and the overall condition of the dog. Bacterial skin infections typically require oral antibiotics and/or the use of topical products such as medicated shampoos, conditioners, sprays, and ointments. Commonly used products include:
- Epi-Soothe® Shampoo
- Malaseb® Shampoo
- Zymox® Shampoo
- GentaVed® Topical Spray
- TrizCHLOR™ Wipes
- Animax® Ointment (prescription required from a veterinarian)
Fungal infections are treated similarly, utilizing antifungal medications, while parasites are addressed with antiparasitic medications.
In addition to targeting the infection directly, other treatments are employed to facilitate skin healing and prevent future infections. For instance, special ear cleaners are used alongside antimicrobial medications to treat ear infections. Omega-3 fatty acid supplementation is another method used to resolve and prevent infections. Prevention plays a crucial role, with regular bathing and grooming being helpful not only in treating existing skin infections but also in preventing their occurrence.
For secondary skin infections, addressing the primary cause is paramount. Skin allergies, for instance, often necessitate medications to reduce inflammation and allergic reactions. Treating a skin infection without addressing the underlying allergy can lead to recurrent infections. Food allergies may require special diets to mitigate skin inflammation. If a food allergy is suspected, the veterinarian will collaborate with the owner to conduct a suitable food trial, systematically eliminating certain ingredients to identify potential allergens.
Recovery and Prevention
The duration of recovery from a skin infection in dogs varies depending on factors such as the type of infection, the effectiveness of treating its primary causes, and the severity of the disease. Adherence to treatment regimens for the required duration often presents the greatest challenge in the recovery process.
Certain skin infections pose difficulties in treatment due to antimicrobial resistance, which develops over time as microbes evolve defenses against medications, rendering them ineffective. In such cases, treatment may extend and necessitate additional testing.
There’s a risk of infections reemerging, particularly if the underlying cause remains untreated or unresolved. Dogs with chronic conditions like allergies or other diseases are more prone to recurrent infections.
Successfully managing skin infections can be intricate, time-intensive, and costly. Adhering closely to the veterinarian’s recommendations and maintaining patience throughout the treatment period are crucial for resolving the infection and preventing its recurrence in your dog.