Adenovirus Infections: CDC Epidemiology, Clinical Syndromes, and Prevention

Per CDC, adenoviruses cause ~1.7 million illnesses annually in the US, with ~2,500 hospitalizations and ~50 deaths.

Epidemiology

• Year-round; peaks late winter/spring.
• All ages; severe disease in infants, immunocompromised, crowded settings (military, dorms).
• Transmission: Respiratory droplets, fecal-oral, fomites, water (pools).

Clinical Syndromes

• Respiratory: Pharyngitis, croup, bronchiolitis, pneumonia (types 3, 4, 7, 14).
• Conjunctivitis: Pharyngoconjunctival fever (pool-associated), epidemic keratoconjunctivitis (types 8, 19, 37).
• Gastroenteritis: Types 40, 41 (enteric adenoviruses) — 2nd to rotavirus.
• Hemorrhagic cystitis: Types 11, 21 (children).
• Disseminated: Immunocompromised (pneumonitis, hepatitis, encephalitis).

Diagnosis & Management

• PCR (respiratory panel, stool) — gold standard.
• Supportive care (most cases).
• Cidofovir/brincidofovir: Severe immunocompromised cases (off-label, nephrotoxic).
• Vaccine: Live oral types 4 & 7 — military only (since 2011).

Prevention

• Hand hygiene, surface disinfection (bleach), pool chlorination, isolation precautions.