Keratoconjunctivitis Associated with Adenovirus Type 37: An Extended Outbreak in an Ophthalmologist's Office

An outbreak of epidemic keratoconjunctivitis occurred in three clusters among patients of an ophthalmologist during 1977–1978. Cases in the third cluster and possibly one case in the first were caused by infection with adenovirus type 37. Among 83 infected patients, the mean interval between a visit to the ophthalmologist's office and the onset of symptoms was 11 days. Conjunctival specimens from 64 (77%) of the patients yielded adenovirus type 37, and adenovirus hexon antigen was identified by counterimmunoelectrophoresis in pooled specimens from the office environment. Infected patients were older and had more glaucoma, and were therefore tested more frequently by tonometry, than noninfected control patients. The association of this outbreak with adenovirus type 37 was made in 1981, the year in which this new serotype was fully described and reference reagents were produced. This is the first report of infection due to adenovirus type 37 in the United States.