When Staphylococcus bacteria, commonly present on a cat’s skin and mucous membranes, overgrow, a staph infection can develop. These bacteria are a normal part of a cat’s microflora. An infection arises when there is an imbalance or a breach in the skin’s natural defenses, allowing these opportunistic microorganisms to multiply unchecked. This often leads to visible skin issues, signaling that the cat’s protective barrier has been compromised.
Causes and Symptoms of Feline Staph Infections
Staph infections can be triggered by several factors. Skin injuries like scratches, wounds, or abrasions provide an entry point for bacteria. Excessive grooming, licking, or scratching can also compromise the skin barrier, creating a favorable environment for bacterial growth. Parasites, including fleas and mites, along with allergic reactions to food or environmental factors like pollen, frequently lead to skin irritation and inflammation, predisposing a cat to secondary bacterial infections.
Cats with weakened immune systems are also more susceptible. Symptoms primarily manifest on the skin. Observable signs include red bumps (papules) or pus-filled lesions (pustules). Crusty lesions, scabs, and circular patches of hair loss, often with redness, are common indicators.
Affected cats may exhibit excessive itching, scratching, or licking. While skin infections are most prevalent, Staphylococcus can also cause infections in other areas, including the ears, upper respiratory tract, or urinary tract. More severe infections can result in abscesses or draining sores.
Veterinary Diagnosis and Treatment
A veterinarian diagnoses a staph infection through a physical examination and by gathering a detailed medical history. Diagnostic tools include skin scrapings, which help rule out other causes like mites. Impression smears, or cytology, involve collecting cells from the affected area to examine them under a microscope, identifying bacteria and inflammatory cells.
Bacterial cultures with sensitivity testing identify the Staphylococcus species and determine effective antibiotics. Treatment involves antibiotics, given orally or as injections, to eliminate bacterial overgrowth. Topical therapies are often used with systemic antibiotics for localized relief and to address surface bacteria. These may include medicated shampoos (e.g., chlorhexidine or benzoyl peroxide), sprays, or ointments. Completing the full course of antibiotics is important, even if symptoms improve, to ensure resolution and prevent antibiotic resistance.
Contagion Risk and Home Care
While Staphylococcus bacteria can be transmitted between animals and from animals to humans, the risk for healthy individuals remains low. Transmission is more likely in those with compromised immune systems, such as newborns or individuals undergoing chemotherapy, or in people with open wounds that contact an infected area. While specific Staphylococcus strains are more common in pets (like S. pseudintermedius) versus humans (S. aureus, including MRSA), cross-species transmission can occur.
Practicing good hygiene, particularly washing hands thoroughly with soap and water after handling an infected cat or applying medication, is recommended. Regularly washing the cat’s bedding in hot water helps reduce the bacterial load. Cleaning shared living spaces can further minimize bacterial spread.
Addressing Underlying Health Issues
Feline staph infections are often secondary conditions, developing as a consequence of another primary health problem. Unless this underlying issue is identified and managed, staph infections are prone to recurring even after initial treatment clears symptoms. The bacteria take advantage of a compromised immune system or a damaged skin barrier.
Common underlying conditions predisposing cats to recurrent staph infections include allergic skin diseases, such as flea allergy dermatitis, environmental allergies (atopic dermatitis), or food allergies. These allergies often lead to chronic itching and skin irritation, weakening the skin’s natural defenses. Endocrine disorders or immunosuppressive diseases like Feline Immunodeficiency Virus (FIV) or Feline Leukemia Virus (FeLV) can also diminish a cat’s immune response, increasing susceptibility to bacterial overgrowth. Therefore, successful long-term management involves treating the current infection and working with a veterinarian to diagnose and address the primary condition.