Long-Term Excretion of Shiga Toxin-Producing Escherichia coli (STEC) and Experimental Infection of a Sheep with O157

Journal of Veterinary Medical Science

Asumi KURI¹  Suk KIM¹  Hiroshi ASAKURA¹  Kouichi TAKESHI³  Sou-ichi MAKINO¹  Teizo TSUKAMOTO²  Masahisa WATARAI¹  Toshikazu SHIRAHATA¹ 

[1] Department of Veterinary Microbiology, Obihiro University of Agriculture and Veterinary Medicine;Osaka Prefectural Institute of Public Health;Hokkaido Institute of Public Health

关键词: bacteriophage;    feces;    O157;    ovine;    STEC;   

DOI  :  10.1292/jvms.64.927

学科分类：兽医学

来源: Japanese Society of Veterinary Science

【 摘 要 】

References(31)Cited-By(2)To investigate a long-term shedding of Shiga toxin (Stx)-producing Escherichia coli (STEC) from sheep, a fifteen-month study for STEC isolation from a sheep, which had yielded STEC before, was attempted. The sheep continued to shed STEC and 39 STEC were isolated. The number of STEC in the feces was estimated at 1.7 × 103 per gram. In addition, although Stx1-negative O157 and stx2-encoding bacteriophage were experimentally infected to the sheep, Stx-positive O157 or Stx2- producing bacterial cells were not detected. The genetical and biochemical characterization of those 39 STEC strains showed that all STEC strains produced Shiga toxin 1 (Stx1) and were divided into three classes (I to III). From phylogenetic analysis of their amino acid sequences, class-I STEC was classified as group 1 comprising mainly human STEC, and classes II/III were as group 2 comprising sheep STEC. Our results suggest that STEC easily colonized in sheep and that the sheep continued to shed STEC, showing that sheep might be an important reservoir for human STEC infection.

【 授权许可】

Unknown