Clinical Manifestations of Adenovirus Infections

Adenovirus infections of the upper respiratory tract are common and, although often subclinical, can result in symptoms of the common cold, pharyngitis, tonsillitis, otitis media, and pharyngoconjunctival fever. Life threatening disseminated infection, severe pneumonia, hepatitis, meningitis, and encephalitis occur occasionally, especially among young infants and immunocompromised hosts. Apart from respiratory involvement, illnesses and presentations of adenovirus include gastroenteritis, conjunctivitis, cystitis, and rash illness. Symptoms of respiratory illness caused by adenovirus infection range from the common cold syndrome to pneumonia, croup, and bronchitis.

Epidemiology

Infection in infants and children can occur at any age. Adenoviruses causing respiratory tract infections usually are transmitted by respiratory tract secretions through person-to-person contact, airborne droplets, and fomites, the latter because adenoviruses are stable in the environment. The conjunctiva can provide a portal of entry.

Incubation Period

Respiratory tract infection, 2 to 14 days; gastroenteritis, 3 to 10 days.

Diagnostic Tests

The preferred methods for diagnosis of adenovirus infection include cell culture, antigen detection, and DNA detection. Adenoviruses associated with respiratory tract disease can be isolated from pharyngeal and eye secretions and feces by inoculation of specimens into susceptible cell cultures

Time Taken to Cure

Symptoms and signs resemble those of a cold (cough, runny nose, mild fever) for about three to five days , about 40% may need hospitalization with severe symptoms of pneumonia, and shortness of breath; other organ related symptoms may develop such as eye, bladder, etc

Adenoviral is Contagious or Not

Adenoviral conjunctivitis is highly contagious, with an incubation period of 7 to 10 days and a duration of 4 to 6 weeks. The virus is shed during the initial 2 weeks of symptoms. Infectious particles can survive on fomites for 2 months.

Treatment of Adenovirus Infection

Treatment of adenovirus infection is supportive. Like most other viral infections, there are no specific drugs that can target the adenovirus. The body’s immune system fights the infection and it resolves in three to five days in most individuals. Randomized clinical trials evaluating specific antiviral therapy have not been performed. However, the successful use of intravenous cidofovir has been reported in immunocompromised patients with severe adenoviral disease.