Molecular epidemiology of adenovirus conjunctivitis in Glasgow 1981-1991

Adenoviruses isolated over a period of 10 years from patients with conjunctivitis were typed by neutralisation test using reference sera and by restriction endonuclease fragment (REF) analysis. Adenoviruses were isolated from 516 of 10,232 patients tested (5.0%); 154 were identified as type 3, 153 as type 4, 70 as type 7, 17 as type 10 and 122 as other types. At any one time, several serotypes co-circulated. The prevalence of types varied. Type 4 was not isolated in the first 2 years and then gradually increased in incidence, becoming the most frequently isolated type after 1987. Two periods of increased isolation frequency occurred: firstly from May to August 1981, when 8-28% of patients per month were found to be adenovirus-positive, with serotype 3 being predominant; and secondly from January 1989 to August 1990, when 8-20% of patients per month were adenovirus-positive, predominantly with type 4. Analysis of REFs showed that several different genotypes exist within serotypes. These also co-circulated over long periods with intermittent changes of the predominant genotype. The prototype strain Ad3GB was isolated more frequently than five other Ad3 genotypes from 1981 to 1988, after which a variant strain Ad3a was most common.