[1][9] Typical symptoms range from those of a common cold, such as nasal congestion, rhinitis, and cough, to difficulty breathing as in pneumonia.

[9] Other general symptoms include fever, fatigue, muscle aches, headache, abdominal pain and swollen neck glands.

[5][4] Other conditions that appear similar include whooping cough, influenza, parainfluenza, and respiratory syncytial virus.

[6] Recognised patterns of clinical features include respiratory, eye, gastrointestinal, genitourinary and central nervous system.

[6] Typical symptoms are of a mild cold or resembling the flu; fever, nasal congestion, coryza, cough, and pinky-red eyes.

[16] Illness is more likely to be severe in people with weakened immune systems, particularly children who have had a hematopoietic stem cell transplantation.

[2] Preschool children with adenovirus colds tend to present with a nasal congestion, runny nose and abdominal pain.

[2] Bronchiolitis obliterans is uncommon, but can occur if adenovirus causes pneumonia with prolonged fever, and can result in difficulty breathing.

[2] In very young children, it may be associated with high fever, sore throat, otitis media, diarrhoea, and vomiting.

[2] Adenovirus infection can cause a gastroenteritis when it may present with diarrhea, vomiting, and abdominal pain, with or without respiratory or general symptoms.

[2] Other signs and symptoms depend on other complications such as dark urine, itching and jaundice in hepatitis, generally in people who have a weakened immune system.

[2] Adenovirus is a rare cause of urethritis in men, when it may present with burning on passing urine associated with red eyes and feeling unwell.

Other types cause sporadic infection and occasional outbreaks; for example, epidemic keratoconjunctivitis is associated with adenovirus serotypes 8, 19, and 37.

Epidemics of febrile disease with conjunctivitis are associated with waterborne transmission of some adenovirus types, often centering on inadequately chlorinated swimming pools and small lakes.

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.

[5] 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.

[8] Other conditions that appear similar include whooping cough, influenza, parainfluenza, and respiratory syncytial virus (RSV).

[7] Strict attention to good infection-control practices is effective for stopping transmission in hospitals of adenovirus-associated disease, such as epidemic keratoconjunctivitis.

[10] Adenovirus can cause severe necrotizing pneumonia in which all or part of a lung has increased translucency radiographically, which is called Swyer-James Syndrome.

[10] Epidemics may spread more quickly in closed populations such as in hospitals, nurseries, long-term care facilities, boarding schools, orphanages and swimming pools.

[12] The first adenoviral strains were isolated from adenoids in 1953 by Rowe et al.[14] Later, during studies on rotavirus diarrhoea, the wider use of electron microscopy resulted in detecting previously unrecognized adenoviruses types 40 and 41, subsequently found to be important in causing gastrointestinal illness in children.

[2] The illness made headlines in Texas in September 2007, when a so-called "boot camp flu" sickened hundreds at Lackland Air Force Base in San Antonio.

[8] In 2020, as a result of infection control measures during the COVID-19 pandemic, rates of adenovirus diarrhoea declined significantly in China.