Increasing importance of viruses in acute otitis media

Acute otitis media is generally considered a simple bacterial infection tha t can be effectively treated with antibiotics. However, despite the extensi ve use of broad-spectrum antibiotics, poor clinical response to treatment o f acute otitis media is common in children. Numerous studies ranging from a nimal experiments to extensive clinical studies have clearly demonstrated t hat respiratory viruses play a crucial role in the aetiology and pathogenes is of acute otitis media. Viral infection of the upper respiratory tract in itiates the whole cascade of events that finally leads to the development o f acute otitis media as a complication. Respiratory viruses induce a releas e of inflammatory mediators in the nasopharynx, increase bacterial coloniza tion and adherence, and have a suppressive effect on the host's immune defe nse. Recent data indicate that at least some types of viruses actively inva de the middle ear. Viruses also seem to enhance the inflammatory process in the middle ear and impair the outcome of the disease. Vaccines against the major viruses predisposing to acute otitis media hold a great promise for the prevention of this disease. Major advances in the management of acute o titis media will require further research into the mechanisms of viral infe ction, viral-bacterial interaction and the host inflammatory response durin g viral infection.