Adenovirus infection

Adenovirus infection is a contagious viral disease, caused by adenoviruses, commonly resulting in a respiratory tract infection. Typical symptoms range from those of a common cold, such as nasal congestion, coryza and cough, to difficulty breathing as in pneumonia. Other general symptoms include fever, fatigue, muscle aches, headache, abdominal pain and swollen neck glands. Onset is usually two to fourteen days after exposure to the virus. A mild eye infection may occur on its own, combined with a sore throat and fever, or as a more severe adenoviral keratoconjunctivitis with a painful red eye, intolerance to light and discharge. Very young children may just have an earache. Adenovirus infection can present as a gastroenteritis with vomiting, diarrhoea and abdominal pain, with or without respiratory symptoms. However, some people have no symptoms. Adenovirus infection in humans are generally caused by Adenoviruses types B, C, E and F. Spread occurs mainly when an infected person is in close contact with another person. This may occur by either fecal–oral route, airborne transmission or small droplets containing the virus. Less commonly, the virus may spread via contaminated surfaces. Other respiratory complications include acute bronchitis, bronchiolitis and acute respiratory distress syndrome. It may cause myocarditis, meningoencephalitis or hepatitis in people with weak immune systems. Diagnosis is by signs and symptoms, and a laboratory test is not usually required. In some circumstances, a PCR test on blood or respiratory secretions may detect adenovirus DNA. Other conditions that appear similar include whooping cough, influenza, parainfluenza, and respiratory syncytial virus. Adenovirus gastroenteritis appears similar to diarrhoeal diseases caused by other infections. Infection by adenovirus may be prevented by washing hands, avoiding touching own eyes, mouth and nose with unwashed hands, and avoiding being near sick people. A live vaccine to protect against types 4 and 7 adenoviruses has been used successfully in some military personnel.