Adenovirus Type 8-Associated Follicular Conjunctivitis and Keratoconjunctivitis in Patients Subjected to Tonometry: I. Virological Findings

Abstract
At the out-patient Eye Clinic of the University Hospital in Uppsala an accumulation of cases of follicular conjunctivitis with or without keratitis was observed from the end of November 1966. From a large number of cases virus isolates were obtained, which were identified as adenovirus type 8. The total number of patients—92 in all—who had undergone tonometry in association with the onset of eye disease, were subjected to more detailed clinical and serological studies. From 43 of them specimens for virus isolation were also examined. In 72 patients (78%) infection with adenovirus type 8 was verified serologically with the hemagglutination-inhibition (HI) test. Of these patients, 39 were subjected to virus isolation and in 29 (74%) adenovirus type 8 was found. In 15 additional patients (16%) 2-fold differences between lowest and highest antibody titer or constant titers equal to or higher than 1 : 5 were observed. In the remaining 5 patients results were inconclusive. The infection was probably introduced by one or two of the three patients, who exerted signs of conjunctivitis at the time of tonometry. On the assumption that tonometry was responsible for transmission of the disease to the remaining 89 patients, which was supported by obtaining a virus isolate from the tonometer after tonometry of a clinically typical case, incubation times could be determined in all, except in 2, who were repeatedly subjected to tonometry. Out of these 87 patients, 81 had incubation times between 4 and 12 days with a pronounced peak at 8 days. In the remaining 6 patients, incubation times varied from 13 to 27 days. To our knowledge, this is the first large epidemic of adenovirus type 8-associated follicular conjunctivitis and keratoconjunctivitis reported from Scandinavia.