For some adenovirus serotypes, the clinical spectrum of disease associated with infection varies depending on the site of infection; for example, infection with adenovirus 7 acquired by inhalation is associated with severe lower respiratory tract disease, whereas oral transmission of the virus typically causes no or mild disease. Outbreaks of adenovirus-associated respiratory disease have been more common in the late winter, spring, and early summer; however, adenovirus infections can occur throughout the year.Several adenoviruses, including Ad5, Ad9, Ad31, Ad36, Ad37, and SMAM1, have at least some evidence of causation of obesity in animals, adipogenesis in cells, and/or association with human obesity. Diagnosis
Diagnosis is by signs and symptoms, and a laboratory test is not usually required. In some circumstances such as severe disease, when a diagnosis needs to be confirmed, a PCR test on blood or respiratory secretions may detect adenovirus DNA. Adenovirus can be isolated by growing in cell cultures in a laboratory. Other conditions that appear similar include whooping cough, influenza, parainfluenza, and respiratory syncytial virus. Since adenovirus can be excreted for prolonged periods, the presence of virus does not necessarily mean it is associated with disease. Prevention
Infection by adenovirus may be prevented by washing hands, avoiding touching own eyes, mouth and nose before washing hands and avoiding being near sick people. Strict attention to good infection-control practices is effective for stopping transmission in hospitals of adenovirus-associated disease, such as epidemic keratoconjunctivitis. Maintaining adequate levels of chlorination is necessary for preventing swimming pool-associated outbreaks of adenovirus conjunctivitis.
Eyes
Adenovirus eye infection may present as a pinky-red eye. Six to nine-days following exposure to adenovirus, one or both eyes, typically in children, may be affected in association with fever, pharyngitis and lymphadenopathy (pharyngoconjunctival fever (PCF)). The onset is usually sudden, and there is often rhinitis. Adenovirus infection can also cause adenoviral keratoconjunctivitis. Typically one eye is affected after an incubation period of up to a week. The eye becomes itchy, painful, burning and reddish and lymphadenopathy may be felt by the ear nearest the affected eye. The symptoms may last around 10-days to three-weeks. It may be is associated with blurred vision, photophobia and swelling of the conjunctiva. A sore throat and nasal congestion may or may not be present. This tends to occur in epidemics, affecting predominantly adults. In very young children, it may be associated with high fever, sore throat, otitis media, diarrhoea, and vomiting. Gastrointestinal tract
Adenovirus infection can cause a gastroenteritis when it may present with diarrhoea, vomiting and abdominal pain, with or without respiratory or general symptoms. Children under the age of one-year appear particularly vulnerable. However, it usually resolves within three-days. It appears similar to diarrhoea diseases caused by other infections. Other organs
Uncommonly the bladder may be affected, presenting with a sudden onset of burning on passing urine and increased frequency of passing urine, followed by seeing blood in the urine a day or two later. Meningism may occur in adenovirus associated meningoencephalitis, which may occur in people with weakened immune systems such as with AIDS or lymphoma.