Overview
Common viral infections causing respiratory illness, conjunctivitis, and gastroenteritis, with military vaccine available for types 4 and 7.
Overview
Adenovirus infections are common viral illnesses caused by over 50 types of adenoviruses. They cause a range of conditions including respiratory infections, conjunctivitis (pink eye), gastroenteritis, and urinary tract infections. A vaccine is available for military personnel (types 4 and 7).
Overview
Adenoviruses are non-enveloped DNA viruses with over 50 recognized types that commonly cause mild, self-limiting infections, particularly in children. Different types have tropism for different tissues, resulting in diverse clinical presentations.\n\nCertain types cause epidemic keratoconjunctivitis (severe eye infection) and pharyngoconjunctival fever (swimming pool conjunctivitis). Types 4 and 7 cause outbreaks of acute respiratory disease in military recruits, for which a live oral vaccine is available. Adenoviruses are notably resistant to many common disinfectants.
Emergency Signs
- signs of dehydration in young children with gastroenteritis (dry mouth, decreased urination, lethargy)\n- severe eye pain or sudden vision changes\n- respiratory distress (mainly a concern in immunocompromised patients)\n- persistent high fever in immunocompromised individuals\n- blood in urine with difficulty urinating
Detailed Symptoms
Most common signs and symptoms
Symptoms vary by adenovirus type and site of infection.\n\nRespiratory (types 1–7): Fever, cough, sore throat, runny nose. Can progress to bronchitis or pneumonia.\n\nPharyngoconjunctival fever (types 3, 7): Fever, sore throat, and conjunctivitis — often associated with swimming pools.\n\nEpidemic keratoconjunctivitis (types 8, 19, 37): Severe eye pain, tearing, light sensitivity, blurred vision.\n\nGastroenteritis (types 40, 41): Watery diarrhea, vomiting, fever.\n\nHemorrhagic cystitis (types 11, 21): Blood in urine, painful urination.
Knowing the symptoms is the first step to a quick response.
Course of Disease
Incubation period is 2–14 days depending on the adenovirus type and site of infection. Respiratory illness typically lasts 3–7 days. Conjunctivitis may persist for 1–4 weeks. Gastroenteritis lasts 5–12 days. Viral shedding may continue for weeks to months after symptoms resolve, particularly in stool.
Diagnosis
How this disease is identified
PCR testing from respiratory secretions, stool, urine, or conjunctival swab is the most sensitive method. Rapid antigen detection tests are available for respiratory and enteric adenovirus types. Viral culture is also used. Serology is less useful for acute diagnosis. In most cases, specific viral testing is not necessary as treatment is supportive regardless of the causative virus.
Treatment
Available treatment methods
Most adenovirus infections are self-limiting and require only supportive care: adequate hydration, rest, and fever-reducing medication as needed. There is no approved antiviral for routine adenovirus infections. Severe infections in immunocompromised patients may be treated with antiviral agents under specialist guidance. Epidemic keratoconjunctivitis is managed with supportive eye care — artificial tears and cold compresses.
Most cases are effectively treated with early diagnosis.
Prevention Details
How to protect yourself
- frequent hand washing with soap and water (adenoviruses are resistant to alcohol-based sanitizers)\n- adequate chlorination of swimming pools\n- disinfection of surfaces with bleach-based solutions (adenovirus is resistant to many common disinfectants)\n- respiratory hygiene: cover coughs, avoid close contact when symptomatic\n- live oral vaccine for adenovirus types 4 and 7 is available exclusively for US military personnel aged 17–50
Preparation is the best protection.
Travel Advice
- adenovirus is not a specific travel-associated risk\n- practice good hand hygiene, especially around young children\n- avoid swimming in poorly chlorinated pools or natural water bodies with known outbreaks\n- military personnel deploying to training facilities should ensure they have received the adenovirus vaccine (types 4 and 7) if eligible
How common is it?
Statistics and geographic data
Adenoviruses circulate worldwide, year-round, with peaks in winter and spring for respiratory types and summer for conjunctivitis (associated with swimming pools). Common in daycare settings, schools, and military barracks. Enteric adenoviruses (types 40, 41) are the second most common cause of childhood viral gastroenteritis after rotavirus.
Risk Factors
Who is most at risk
- young children (daycare and school settings)\n- military recruits (crowded training facilities)\n- immunocompromised individuals (organ transplant, HIV, chemotherapy)\n- swimmers in inadequately chlorinated pools\n- healthcare workers with patient contact\n- residents of congregate living facilities
Complications Details
Potential complications
Complications are generally rare in healthy individuals. Immunocompromised patients can develop disseminated disease, severe pneumonia, hepatitis, and hemorrhagic cystitis. Neonatal adenovirus infection can cause severe liver damage. Post-infectious bronchiolitis obliterans is a rare complication in children following severe adenovirus pneumonia. Intussusception has been reported in association with enteric adenovirus types.
Recovery & Outlook
Expected outcomes and recovery
Prognosis is excellent for immunocompetent individuals — most infections resolve within 5–10 days without complications. Adenovirus infections can be severe or fatal in immunocompromised patients (organ transplant recipients, individuals with HIV). In military recruit populations, adenovirus pneumonia can be serious if vaccination is not administered.