[ODP5D] d. 疫学・分子疫学

[ODP-105] 日本の野鳥を対象としたEscherichia albertiiの保菌調査

○日根野谷 淳^1,2,3，Sharda Prasad Awasthi¹，安田 憲朋¹，長野 恵吾²，Jayedul Hassan¹，竹平 京司¹，畑中 律敏¹，井上 春奈⁴，山崎 伸二^1,2,3 (¹大阪府大・院生命環境・獣医，²大阪府大・生命環境・獣医，³大阪府大・アジア健康科学研究所，⁴わんぱーくこうち・アニマルランド)

Escherichia albertii is an emerging zoonotic foodborne pathogen which has caused several outbreaks particularly in Japan. Although birds have been considered as the important reservoirs of this bacterium, information regarding the prevalence in birds is still severely lacking. We performed a survey of E. albertii in wild birds in Japan, and examined the characteristics of isolates. E. albertii was detected in the specimen from intestines of 3.6% birds (5/140 bodies) by PCR, and 4 E. albertii were isolated from a swallow co-infected with 2 different E. albertii strains and 2 pigeons in a flock using XRM-MacConkey agar. They were assigned to biogroup 3, showed no resistance to any of 16 tested antimicrobials, and classified into 3 EAOgenotypes (EAOg2, EAOg33 and untypable). Similar to clinical E. albertii strains, they carried virulence genes including eae (n=4; alpha8, beta1 and sigma), paa (n=4), Eccdt-I (n=2) and stx2f (n=1) in addition to Eacdt. The stx2f gene-positive strain produced biologically active Stx2f. Interestingly, the stx2f genes in the strain were located on an inducible bacteriophage, which could confer the ability to produce Stx2f to E. coli. In conclusion, Japanese wild birds examined in this study carried E. albertii at the similar level as previously reported in birds. The bird strains may have the potential virulence to cause intestinal diseases in humans.