An Outbreak of Enteric Adenovirus Type 41 Endemic in Fjieda, Japan

To determine the incidence of enteric adenovirus, 447 stool specimens were collected between January 1991 to October 1992 from children with gastroenteritis at a clinic in Fujieda, Japan. Each specimen was tested for adenovirus group antigen and for specific enteric adenovirus types 40 and 41 (Ad40/41) by using monoclonal antibody enzyme immunoassays. Adenovirus was found in 10.7% (48 of 447) cases and 77.1% (37 of 48) of them were Ad40/41. There were two peaks of adenovirus infection May and November 1991. The virus was isolated with 293 cells from 48 of adenovirus positive specimens, and then was typed according to the SmaI cleavage pattern of the viral DNA and by neutralization with specific antisera. Ad41 was predominantly isolated in 64.6% (31 of 48), and Ad40 was in 10.4% (5 of 48). The remaining virus isolates were typed as Ad1, 2, 5, and 6. Ad41 was founded in 89.3% (25 of 28) from October 1991 to March 1992. Though Sma I and Hind III cleavage identified six Ad41 variants in the period, the variants identified from October 1991 to March 1992 were only two. The results indicated two variants of Ad41 strains caused an outbreak during the end of 1991 to early 1992 in Fujieda.