Adenovirus Symptoms
Adenovirus infection primarily causes diarrhea (more prominent than vomiting or fever), respiratory symptoms, and has an incubation period of 3-10 days with illness lasting ≥1 week—longer than other enteric viral pathogens. 1
Gastrointestinal Manifestations
- Diarrhea is the predominant symptom, more prominent than vomiting or fever in adenovirus infection 1
- Gastroenteritis occurs particularly with serotypes 40 and 41, which primarily affect the gut and contribute to 5%-20% of hospitalizations for childhood diarrhea 1
- In immunocompromised patients (particularly those with impaired cellular immunity), adenovirus can cause life-threatening gastroenteritis 1
- Nausea and vomiting may occur but are less prominent than diarrhea 1
Respiratory Symptoms
- Respiratory symptoms are often present alongside gastrointestinal manifestations 1
- Upper respiratory tract involvement including sore throat, rhinorrhea, and pharyngalgia can occur 1
- Adenovirus is associated with acute respiratory distress syndrome in severe cases 1
- In institutional outbreaks, severe acute respiratory disease with hypoxemia may develop, particularly in vulnerable populations 2
Ocular Manifestations
- Keratoconjunctivitis epidemica (epidemic keratoconjunctivitis/EKC) is a classic presentation 1
- Conjunctivitis may present with swollen and tender preauricular or submandibular lymph nodes 1
- The infection is highly contagious and can survive for many weeks on surfaces 1
Systemic and Other Symptoms
- Fever occurs but is less prominent than diarrhea in enteric adenovirus infections 1
- Incubation period: 3-10 days 1
- Duration of illness: ≥1 week, which is notably longer than other enteric viral pathogens 1
- Myalgia and headache may be present 1
High-Risk Populations and Severe Disease
- In immunocompromised patients (AIDS, hereditary immunodeficiencies, transplant recipients), adenovirus can cause disseminated and potentially life-threatening disease 3, 4
- Severe manifestations may include hemorrhagic cystitis, hepatitis, hemorrhagic colitis, pancreatitis, nephritis, or meningoencephalitis 5, 6
- Fatality rates for untreated severe adenovirus pneumonia or disseminated disease may exceed 50% in immunocompromised patients 5, 6
- Multisystem failure including acute renal failure can occur in severe cases 2
Pediatric Considerations
- Peak incidence is among children less than 2 years of age 1
- Older children and adults may be infected with or without symptoms 1
- Asymptomatic shedding has been documented, though infectivity generally parallels symptomatic disease 1
Transmission and Contagiousness
- Person-to-person transmission is the principal mechanism for spread 1
- The virus is highly contagious and patients should minimize contact with others for 10-14 days from onset of symptoms in the last eye affected (for conjunctivitis) 1
- Outbreaks tend to occur in hospitals, day-care settings, and institutional facilities 1, 2