Introduction:
Most parents haven’t heard of adenovirus, but most children get it several times – especially in the first 2 years of life.

What is it?
Adenoviruses are very common viruses that can cause infections in children. There are over fifty subtypes of adenovirus. They most commonly cause upper respiratory tract infections, including the common cold, sore throats, tonsillitis, ear infections, and conjunctivitis. Another common adenoviral infection is pharyngoconjunctival fever (sore throat, red eyes, and a fever).

Less commonly, adenoviruses cause croup, pertussis syndrome, or bronchiolitis.

Adenoviruses are a common cause of gastroenteritis.They can also cause urinary tract infections (including hemorrhagic cystitis – a UTI with blood in the urine).

In rare cases, adenoviruses cause pneumonia, meningitis, or encephalitis.

Who gets it?
Anyone can get adenoviral infections, from newborns to the elderly. Infections are most common between the ages of 6 months and 2 years. Children in day care are most likely to get repeated adenoviral infections.

Respiratory tract infections are slightly more common in the spring (from late winter, through spring, and into early summer). Adenoviruses are common causes of spring colds.

Adenoviral gastroenteritis occurs with the same frequency year round.

The very young and the immunocompromised are at the highest risk for significant illness.

What are the symptoms?
The symptoms depend on the location of the infection, but often include a fever. The sore throat, for instance, may be confused with strep throat in the absence of a throat swab.

Is it contagious?
Adenovirus can spread via direct contact, droplet transmission, and fecal-oral transmission. Because the virus is stable in the environment, fomites are a common cause of spread. Spread has been documented from contaminated swimming pools and towels.

How long does it last?
People usually develop symptoms within 2 weeks of exposure. The length of the disease is usually typical for the location (e.g. less than 7 days for gastroenteritis).

How is it diagnosed?
The diagnosis is suspected based on the history and physical exam. It may be confirmed by viral studies. These may include swabs of the eyes, throat, or stool as appropriate. Occasionally blood or urine tests are performed.

How is it treated?
Treatment is usually aimed at controlling symptoms. Antibiotics are not helpful.

How can it be prevented?
Adenovirus infections are difficult to prevent. Some cases can be prevented by good hand washing, and by avoiding contaminated objects.

Adenoviral conjunctivitis, for instance, has sometimes spread rapidly in the offices of eye doctors. Good hand washing, and using disposable or sterile instruments and bottles of eye drops can interrupt this spread.

Adequate chlorination of pools can also prevent some adenoviral infections.