Acute otitis media (OM) and OM with effusion are common childhood diseases. Otitis media is a condition marked by inflammation of the middle ear. Otitis media with effusion typically means a long-term (chronic) middle ear inflammation with secretion of fluid into the middle ear due to the blockage of the canal leading from the middle ear to the mouth (eustachian tube). The fluid involved can be sterile (no organisms) or infected with disease causing organisms, such as bacteria or viruses.