Adenoviruses cause disease by infecting epithelial cells in a variety of tissues and organs. Specific syndromes tend to be associated with particular adenovirus serotypes, of which there are nearly 50.
In immunocompetent patients they cause epidemics of pharyngoconjunctival fever (serotypes 3, 7), keratoconjunctivitis (serotypes 8, 19) and lower respiratory infection (in military recruits). They also cause endemic upper respiratory tract infection (serotypes 1, 2, 5), a small proportion of pneumonia (about 10% in children), sporadic gastroenteritis (serotypes 40, 41) and haemorrhagic cystitis (serotypes 7, 11, 21, 35).
In immunosuppressed patients they may cause disseminated infection involving the lung, liver, gut and urinary tract. Haemorrhagic cystitis and pneumonia are the most frequent adenovirus syndromes in transplant recipients. There is no effective antiviral therapy and no vaccines available for general use.