Oral complications like gingivitis and stomatitis are common in retrovirus-positive cats and can severely impact quality of life. Below, we'll explore the link between retroviral infection and dental disease, emphasizing the importance of accurate diagnosis, effective treatment, and preventive care.

Understanding FeLV and FIV

FeLV spreads through body fluids—blood, saliva, nasal secretions, milk, urine, feces—and vertically from queens, adult felines who are pregnant or nursing, to their kittens. It initially affects lymphoid tissue, then spreads via white blood cells to the bone marrow, leading to immune dysfunction through T-cell apoptosis or anergy.

FIV is transmitted via bite wounds, introducing infected white blood cells through saliva. After an acute phase, the virus enters a long asymptomatic period during which immune decline occurs. CD4+ and CD8+ T-cell depletion predisposes cats to chronic infections. Eventually, cats with FIV experience weight loss and immunodeficiency.

How Retroviruses Impair Immune Function

Retroviruses impair immune function by targeting T cells and bone marrow precursors, reducing antibody production and cellular immunity. This can contribute to conditions like:

• Chronic inflammation (e.g., gingivostomatitis, dermatitis, otitis)
• Delayed wound healing
• Opportunistic infections (e.g., recurrent URIs)
• Hematologic changes (e.g., anemia, neutropenia)
• Oral disease (e.g., gingivitis, stomatitis)
• Neoplasia (e.g., lymphoma, especially T-cell in FeLV and B-cell in FIV)

Feline retroviruses, like FIV and FeLV, impair immune function by targeting and disrupting key components of the immune system, including T cells and bone marrow precursors. This immunosuppression leads to reduced antibody production, neutropenia, and impaired cellular immunity, making cats more vulnerable to chronic inflammation, delayed wound healing, and opportunistic infections.

 

Oral Disease in Cats: A Common Concern

Dental disease affects 50–90% of cats over age 4.² Oral diseases are common in cats due to factors such as plaque accumulation, immune responses to oral bacteria, dietary influences, and age-related changes.

Treatment typically involves a combination of professional dental cleanings and medical management using antibiotics, corticosteroids, or immunomodulatory agents, like feline interferon, to control pain and inflammation. In cases of severe inflammation or resorptive lesions, tooth extraction may be the best course of treatment.

The Link Between Retrovirus and Feline Dental Disease

Research suggests a strong connection between retrovirus-positive status and dental and periodontal disease in cats.

A 2006 IDEXX study found that there was a 14.2% increase in the prevalence of oral disease (gingivitis, stomatitis, plaque, calculus, periodontal disease, feline odontoclastic resorption lesion, or other oral disease) in retrovirus-positive cats.¹

More specifically, cats with gingivitis were 14.3% more likely to be retrovirus-positive, and cats with stomatitis were 23.9% more likely to be retrovirus-positive. This means that almost one in every seven cats with oral disease has a retrovirus infection.¹

Several other studies have found a significant association between FIV seropositivity and oral inflammatory disease.

The link between inflammation and immune dysregulation in oral disease raises questions as to whether immunosuppressive viruses such as FIV or FeLV contribute, directly or indirectly, to oral inflammatory disease in cats. Histopathological studies have found a wide range of inflammatory cell types in feline chronic gingivostomatitis (FCGS).

The abundance of CD8+ lymphocytes suggests that cytotoxic T-cell immune responses may be a key component of the condition. Furthermore, oral inflammatory lesions and signs of pain improved with antiviral interferon treatment, research shows. The effect of FIV or FeLV infection is more likely to be indirect via systemic immunosuppression rather than through mediators released by retrovirus-infected leukocytes that have migrated into the oral mucosa.

Clinical Recommendations

AAFP recommends cats be tested:

• As soon as possible after they are acquired
• Following exposure to an infected cat or a cat of unknown infection status.
• Prior to vaccination against FeLV or FIV.
• Whenever clinical illness occurs, regardless of previous testing status.

FeLV can be tested at any age, since blood tests detect the antigen. FIV testing is recommended after 6 months to avoid maternal antibody interference. Refer to the 2020 AAFP Feline Retrovirus Testing and Management guidelines for confirmatory testing.

The Benefits of Regular Testing

Including retrovirus testing as part of an annual wellness screening helps to identify retrovirus status before symptoms appear. This early identification can lead to improved health outcomes, not just for infected cats, but also for cats who may be at risk for transmission.

Both FeLV and FIV are highly transmissible to healthy cats through contact with infected animals. Even if a cat has tested negative in the past, an infection can still occur later in life. Refer back to the AAFP Feline Retrovirus Testing and Management guidelines for retesting guidance.

Takeaway for Clinical Practice

Including retrovirus testing in annual wellness exams—even for asymptomatic cats—can improve outcomes. Early identification helps to prevent transmission, enhance quality of life, guide treatment, and enable timely intervention. Given the strong link between retroviruses and oral disease, veterinarians should test cats with dental issues for FeLV and FIV as part of the diagnostic workup. Understanding retroviral status opens the door for improved illness management and helps prevent spread to other cats.

References:

1. IDEXX Laboratories. (n.d.). Oral disease and retrovirus infection in felines. Retrieved from https://www.idexx.com/files/feline-retroviruses-oral-diseases.pdf

2. Cornell Feline Health Center. (n.d.). Feline dental disease. Cornell University College of Veterinary Medicine. Retrieved from https://www.vet.cornell.edu/departments-centers-and-institutes/cornell-feline-health-center/health-information/feline-health-topics/feline-dental-disease