Viral Pneumonia in Children

Viral pneumonia in children is infection of the lung parenchyma by respiratory viruses, and it accounts for most pneumonia in children under 5 years.

• Causes include respiratory syncytial virus, rhinovirus, influenza, parainfluenza, human metapneumovirus, adenovirus, coronaviruses and measles.
• It follows an upper respiratory prodrome and is commonest in winter or rainy season epidemics.
• Illness is generally milder and more gradual than bacterial pneumonia, but severe disease can occur, especially with influenza, adenovirus and measles.
• Bacterial coinfection occurs in a minority and worsens outcome.

Gradual onset with diffuse signs.

• Coryza, cough, low to moderate fever, and fast breathing.
• Wheeze and widespread fine crackles, often bilateral.
• Conjunctivitis, rash, myalgia and sore throat depending on the virus.
• Mild to moderate respiratory distress; severe cases have hypoxia.
• The child is often less toxic than with bacterial pneumonia.
• Differential diagnosis: bacterial pneumonia, bronchiolitis, asthma, pertussis, atypical pneumonia, tuberculosis, foreign body, heart failure and pneumocystis pneumonia.
• Complications: respiratory failure, secondary bacterial pneumonia, acute respiratory distress syndrome, otitis media, myocarditis (rare), post-viral wheeze and bronchiolitis obliterans (adenovirus).

Diagnosis is clinical, supported by viral testing.

• Respiratory rate, saturation, work of breathing.
• Nasopharyngeal polymerase chain reaction panel for viruses.
• Chest X-ray: bilateral perihilar infiltrates, hyperinflation, patchy atelectasis. Not required in mild disease.
• Full blood count (normal or lymphocytosis) and C-reactive protein (low). Raised markers raise concern for bacterial coinfection.
• Blood cultures in toxic children.
• HIV test and tuberculosis assessment in at-risk children.

Supportive care; antivirals for selected viruses.

• Supportive: oxygen for saturation below 92 percent, fluids, antipyretics (paracetamol 15 mg/kg every 6 hours), nasal suction and nutrition.
• Pharmacological: antibiotics not routinely needed. Give amoxicillin 40 to 45 mg/kg twice daily if bacterial infection cannot be excluded, severe disease or deterioration.
• Influenza: oseltamivir for 5 days, twice daily (under 1 year 3 mg/kg per dose; 1 year or older, 15 kg or less 30 mg, 15 to 23 kg 45 mg, 23 to 40 kg 60 mg, over 40 kg 75 mg), started within 48 hours for severe or high-risk disease.
• Measles pneumonia: vitamin A 200,000 IU once daily for 2 days (100,000 IU for ages 6 to 11 months), with antibiotics for secondary infection.
• Severe viral disease in immunocompromised children: antivirals directed by a specialist.
• Respiratory support: high-flow oxygen, continuous positive airway pressure, ventilation.
• Special groups: infants under 3 months, immunocompromised, chronic lung disease and heart disease need admission.
• Red flags: hypoxia, apnoea, exhaustion, persistent high fever, worsening after initial improvement (secondary infection), and age under 3 months.
• Follow-up: review in 48 hours; symptoms can last 2 to 3 weeks. Immunise against influenza and measles.