(Science: chest medicine) this refers to a type of pneumonia that does not follow the typical signs and symptoms of pneumonia. A number of different viral and bacterial agents have been identified which can cause this form of respiratory infection.
Examples include chlamydia pneumonia, psittacosis, Mycoplasma, influenza a or B, adenovirus and Legionella. Antibiotics will be necessary in all but the mildest cases. Symptoms generally improve in less than 2 weeks.