Primary Causes:

1. Feline Herpesvirus (FHV-1):

• Prevalence: The most common cause, responsible for approximately 80% of cases.
• Nature: Establishes a lifelong, latent infection.
• Trigger: Stress can reactivate the virus, causing recurrent symptoms.
• Complication: Frequently leads to painful corneal ulcers.

2. Feline Calicivirus (FCV):

• Prevalence: The second most common viral cause.
• Hallmark Symptom: Characteristic oral ulcers.
• Additional Effect: Can cause transient joint inflammation (lameness).
• Note: Numerous variable strains exist.

3. Bacterial Infections (Often Secondary):

• Common culprits include Chlamydia felis, Bordetella bronchiseptica, and Mycoplasma.
• These typically exploit the damage caused by a primary viral infection.

Lower Respiratory Infections

Pneumonia:

• An infection deep within the lung tissue (alveoli).
• More severe than URI and requires aggressive, prompt treatment.
• Can be caused by bacteria, viruses, fungi, or aspiration.

Bronchitis:

• Inflammation of the airways (bronchi).
• May be triggered by infection or allergies.
• Often develops into a chronic condition requiring long-term management.

Recognizing the Symptoms of Respiratory Infections

Upper Respiratory Infection (URI) Symptoms

Early Signs:

• Frequent sneezing
• Clear, watery nasal discharge
• Watery eyes (epiphora)
• Mild lethargy or decreased activity
• Slight reduction in appetite

Progressive/Worsening Symptoms:

• Thick, yellow, or green nasal discharge
• Eye discharge that may crust over
• Mouth breathing (indicating nasal congestion)
• Fever
• Significant lethargy and weakness
• Anorexia (complete refusal to eat)

Herpesvirus-Specific Signs:

• Corneal ulcers (squinting, pain, cloudiness)
• Prominent third eyelid
• Severe conjunctivitis

Calicivirus-Specific Signs:

• Painful oral ulcers on the tongue, gums, or palate
• Excessive drooling
• Limping or lameness due to joint pain
• High fever

Pneumonia Symptoms: A Medical Emergency

Critical Warning Signs:

• Labored or difficult breathing (dyspnea)
• Rapid, shallow breathing (tachypnea)
• Open-mouth breathing while at rest
• Blue-tinged gums or tongue (cyanosis)
• Extreme lethargy or collapse
• Complete loss of appetite (anorexia)
• High fever or sometimes low body temperature

Immediate veterinary care is required for any cat showing these signs.

Risk Factors and Transmission

High-Risk Populations

How Infections Spread

Respiratory pathogens are transmitted through:

• Direct contact with an infected cat (nose-to-nose).
• Indirect contact via shared bowls, litter boxes, toys, or bedding.
• Airborne droplets from sneezes or coughs.
• Fomites on human hands, clothing, or grooming tools.
• Vertical transmission from mother to kittens during birth.

The Veterinary Diagnosis Process

Step 1: Physical Examination

The veterinarian will conduct a thorough exam, assessing:

• Body temperature and heart rate
• Lung and airway sounds with a stethoscope
• Eyes for ulcers or discharge
• Mouth for ulcers or inflammation
• Hydration status and body condition

Typical Cost: $50 - $100

Step 2: Diagnostic Testing (If Needed)

1. PCR (Polymerase Chain Reaction) Testing:

• Purpose: Precisely identifies specific viral and bacterial DNA/RNA.
• Sample: Nasal swab, ocular swab, or oral swab.
• Tests For: Herpesvirus, Calicivirus, Chlamydia, Bordetella.
• Typical Cost: $100 - $200

2. Chest X-rays (Radiographs):

• Purpose: Essential for diagnosing pneumonia; reveals patterns of lung inflammation, fluid, or consolidation.
• Typical Cost: $150 - $300

3. Blood Work (CBC & Chemistry Panel):

• Purpose: Evaluates overall health, checks for elevated white blood cells (indicating infection), and assesses organ function.
• Typical Cost: $150 - $250

4. Transtracheal Wash or Bronchoalveolar Lavage:

• Purpose: For severe pneumonia cases; retrieves a fluid sample from the lungs to culture bacteria and determine the most effective antibiotic.
• Typical Cost: $300 - $600

Estimated Total Diagnostic Costs

• Simple URI (Exam Only): $50 - $100
• Complex URI (Exam + Basic Tests): $200 - $400
• Pneumonia Workup (Full Diagnostics): $600 - $1,200+

Treatment and Management Options

Supportive Care (The Cornerstone of URI Treatment)

1. Maintain Hydration:

• Encourage drinking with fresh water, broth, or tuna water.
• Subcutaneous or IV fluids may be administered if dehydrated.

2. Support Nutrition and Appetite:

• Offer strong-smelling, palatable foods (pâté, fish).
• Gently warm food to enhance aroma.
• Hand-feed if necessary.
• Veterinarian may prescribe appetite stimulants (e.g., mirtazapine).

3. Ease Breathing with Humidity:

• Use a humidifier near your cat's resting area.
• Bring your cat into a steamy bathroom for 10-15 minutes several times a day.

4. Provide Nursing Care:

• Gently clean crusted discharge from eyes and nose with a warm, damp cloth.
• Ensure a warm, quiet, and stress-free isolation area.

Medications

• Antibiotics: Prescribed for secondary bacterial infections (e.g., Doxycycline, Amoxicillin-clavulanate).
• Antivirals: Famciclovir is used specifically for severe feline herpesvirus infections.
• Ocular Medications: Antibiotic ointments or antiviral eye drops for eye involvement.
• Nebulization: Delivers saline or medication mist directly to the airways in severe cases.

Hospitalization Criteria & Pneumonia Treatment

Hospitalization is necessary when a cat requires:

• IV fluid therapy for dehydration.
• Assisted feeding (e.g., feeding tube).
• Oxygen therapy for respiratory distress.
• Injectable antibiotics and constant monitoring.

Pneumonia Treatment Protocol is Aggressive and Typically Includes:

1. Hospitalization for 3-7 days.
2. IV fluids and broad-spectrum IV antibiotics.
3. Oxygen therapy if blood oxygen is low.
4. Nebulization and coupage (chest physiotherapy).
5. Nutritional support, often via feeding tube.

Cost Analysis: What to Expect

Prevention: Your Best Defense

1. Vaccination

• Core Vaccine: The FVRCP vaccine protects against Feline Viral Rhinotracheitis (herpes), Calicivirus, and Panleukopenia.
• Schedule: Kittens need a series (e.g., 8, 12, 16 weeks), with a booster one year later, then every 3 years for adults.
• Reality Check: Vaccination may not prevent infection entirely but dramatically reduces the severity and duration of illness.

2. Environmental & Stress Management

• In Multi-Cat Homes: Isolate new or sick cats for 1-2 weeks. Provide separate bowls and litter boxes.
• Reduce Stress: Use synthetic pheromone diffusers (Feliway), ensure ample resources (food stations, litter boxes, perches), and maintain a predictable routine.
• Practice Hygiene: Wash hands between handling cats, disinfect surfaces regularly, and wash bedding frequently.

3. For Shelters and Rescues

• Implement strict intake quarantine protocols (10-14 days).
• Vaccinate immediately upon intake.
• Maintain excellent ventilation and sanitation.

Managing Chronic and Recurrent Issues

Feline Herpesvirus (Lifelong Management)

• Stress Reduction is Paramount: This is the single most important factor in preventing flare-ups.
• Supplements: L-lysine is commonly used, though its efficacy is debated; consult your vet.
• Antiviral Therapy: Famciclovir can be used during active flares.
• Ocular Health: Regular monitoring for corneal ulcers is essential.

Post-Viral Chronic Rhinitis

Some cats suffer permanent damage to nasal passages, leading to:

• Chronic, persistent nasal discharge and congestion.
• Recurrent bacterial sinus infections.
• This condition is managed, not cured, with intermittent antibiotics and supportive care.

When to Seek Emergency Care

Contact your veterinarian or an emergency clinic immediately if your cat exhibits:

• Any difficulty breathing (labored, open-mouth, rapid).
• Blue or purple gums (cyanosis).
• Collapse or extreme weakness.
• Refusal to eat or drink for more than 24 hours.
• High fever (over 103.5°F / 39.7°C) or hypothermia.

Prognosis and Expected Outcomes

• Healthy Adult with Simple URI: Excellent prognosis; most recover fully in 7-14 days, though many remain carriers.
• Kittens with URI: Prognosis is good with prompt care, but severe cases can be fatal, especially in very young or weak kittens.
• Pneumonia: Prognosis is guarded. With aggressive, timely treatment, survival rates range from 60% to 80%. Some cats may have residual lung damage.

Conclusion

Feline respiratory infections, from common colds to severe pneumonia, are a significant concern for cat owners. Understanding the symptoms, risk factors, and necessary actions empowers you to protect your cat's health.

Proactive prevention through vaccination, stress management, and biosecurity is crucial. Never hesitate to seek veterinary care, especially for high-risk cats or when symptoms escalate. By working closely with your veterinarian, you can ensure your cat—even one with a chronic condition like herpesvirus—receives the care needed for a long, comfortable, and happy life.

Related Articles:

• Essential Kitten Health: A Guide to Common Issues
• The 2026 Cat Vaccination Schedule: What Your Vet Recommends
• Feline Stress: Recognizing the Signs and Effective Management Strategies
• Emergency Cat Care: A Guide to Knowing When to Seek Immediate Help