Adenovirus-associated gastro-enteritis in the north-west of England: 1991-1994

Faeces, positive for adenoviruses by electron microscopy on initial examination at Manchester Public Health Laboratory (PHL) or Preston PHL during the period 1991-1994, were examined by an enzyme immunoassay which differentiated Ad40, Ad41 and non-AdF strains. Isolation and serotyping by neutralisation of non-AdF strains were attempted in PLC/PRF/5 cells. Of 452 specimens examined, 99 (22%) contained Ad40, 209 (46%) Ad41 and 144 (32%) non-AdF serotypes. From 1991 to 1993 the ratio of Ad40 to Ad41 was constant at approximately 1 to 1.6, but in 1994 it was almost 1 to 5. Non-AdF serotypes, of which Ad1 and Ad2 were the most common, accounted for 44% of specimens tested from 1991, but this dropped to 20% of those from 1994. An age/sex analysis showed that half the specimens examined were from infants under one year old, and that overall the male/female ratio was 3 to 2. The significance of these results is discussed, including the changing prevalence of Ad40 and Ad41, and the role of non-AdF serotypes in gastro-enteritis.