Epidemic keratoconjunctivitis: a community outbreak of mixed adenovirus type 8 and type 19 infection

During the fall and winter of 1973, 145 cases of epidemic keratoconjunctivitis were diagnosed in Nashville, Tennessee. Of the 74 cases studied virologically and/or serologically, 62% were caused by adenovirus type 8, and 28% were caused by adenovirus 19. Whereas adenovirus type 8 was isolated only from conjunctival scrapings, adenovirus type 19 was isolated from nose and throat swabs as well as from conjunctivae. The two viruses produced clinically indistinguishable eye disease and household secondary attack rates that were not statistically different. Regardless of etiology, the secondary attack rate in households was significantly higher among the contacts of those patients who had severe disease for greater than 28 days than among the contacts of patients who had milder disease of shorter duration.