A virological and epidemiological study of patients with acute hearing loss.

Virological and epidemiological data were examined in thirty-nine patients with acute hearing loss. The hearing loss was unilateral in thirty-one patients and bilateral in eight. There was a history of upper-respiratory-tract infection before onset of deafness in ten of the patients. Cases were more common in the autumn, with nineteen of the cases occurring in the 3 months from September to November. About half of the patients were 20-40 years old and half 46-73 years old; only one patient was aged less than 20 years. Antibodies to several common viruses were titrated, and there was evidence of recent infection by mumps virus in one case and by Mycoplasma pneumoniae in another. Although no evidence of recent virus infection was found in the remaining patients, it is suggested that the condition may be viral in origin and that further studies should be undertaken.