Pathophysiology

URTIs begin with the introduction of viruses or bacteria, often via contaminated hands or inhalation of droplets from coughs or sneezes. The body’s defenses include mucus, nasal hairs, ciliated cells, tonsils, adenoids, and immune factors. Infection occurs when these defenses are overcome, leading to inflammation, swelling, and fever. Individuals with weakened immune systems are at higher risk for severe diseases.

Etiology

Most URTIs are caused by viruses such as rhinoviruses, adenoviruses, coronaviruses, and respiratory syncytial virus. Bacterial causes are less common but important to recognize.

Clinical Presentation and Management

1. Rhinitis

• Symptoms: Sneezing, runny or stuffy nose, itchy nose, occasional nosebleeds.
• Diagnosis: Clinical.
• Treatment: Nasal saline rinses, steam inhalation, decongestants, corticosteroid nasal sprays. Antibiotics only if bacterial superinfection is suspected.

2. Rhinosinusitis

• Bacterial suspicion: Persistent symptoms >10 days, worsening after initial improvement, or severe fever for ≥3 days.
• Diagnosis: Clinical; lab tests rarely needed.
• Treatment: Most cases are self-limiting. Consider antibiotics (e.g., amoxicillin-clavulanic acid) if symptoms persist or worsen. Refer children with ethmoidal sinusitis and fever to ENT.

3. Viral Nasopharyngitis

• Symptoms: Fever (especially in children), foul breath, sore throat.
• Treatment: Supportive, 
• decongestants, antipyretics, analgesics.

4. Pharyngitis

• Viral: Sore throat, fever, red eyes, dysphagia, mild exudate. Supportive care only.
• Bacterial (Group A Streptococcus): Sore throat, odynophagia, vomiting, headache, absence of cough. Use CENTOR score for diagnosis. If score ≥3, treat with penicillin or amoxicillin; alternatives for penicillin allergies include azithromycin or clindamycin. Complications include abscesses, otitis media, rheumatic fever, and glomerulonephritis.

5. Epiglottitis

• Cause: Usually Hemophilus influenzae type b; mainly in children <5 years.
• Symptoms: Sudden onset sore throat, drooling, fever, breathing difficulty, tripod position.
• Management: Emergency, hospital admission, airway monitoring, IV antibiotics (e.g., ceftriaxone), fluids.

6. Laryngotracheitis (Croup)

• Cause: Human parainfluenza viruses.
• Symptoms: Painful swallowing, loss of voice, inspiratory stridor, tachypnea, cyanosis.
• Management: Hospitalize if airway compromise or dehydration. Humidified oxygen, inhaled epinephrine, glucocorticoids for moderate cases.

Prevention

• Promote regular hand washing and proper coughing/sneezing etiquette.
• Advice against smoking.
• Encourage immunization against vaccine-preventable respiratory infections (e.g., measles, pertussis, influenza, Hib).

Practical Considerations for Sub-Saharan Africa

• Resource limitations: Rely on clinical diagnosis; reserve antibiotics for clear bacterial cases to prevent resistance.
• Seasonality: Prepare for increased cases during the rainy season.
• Child health: Prioritize immunization and early referral for severe cases.
• Community education: Engage in public health campaigns on hygiene and vaccination.

Conclusion

Most URTIs are viral and self-limiting. Accurate diagnosis and judicious use of antibiotics are essential to reduce resistance. Preventive strategies, especially hygiene and immunization, are critical in sub-Saharan Africa.