Transmission of extended-spectrum cephalosporin-resistant Salmonella harboring a blaCMY-2-carrying IncA/C2 plasmid chromosomally integrated by ISEcp1 or IS26 in layer breeding chains in Japan.

Dissemination of extended-spectrum cephalosporin (ESC)-resistant Salmonella is a public health concern in the egg production industry. ESC-resistant Salmonella often acquires the bla gene via insertion sequences (ISs). Therefore, this study aimed to assess antimicrobial resistance in Salmonella from Japanese layer breeding chains and egg processing chains, and determine the genetic profiles of IS-like elements in ESC-resistant Salmonella. Antimicrobial susceptibility testing was performed on 224 isolates from 49 facilities involving layer breeder farms, hatcheries, pullet-rearing farms, and layer farms in breeding chains along with egg processing chains. ESC-resistant Salmonella strains were whole-genome sequenced. Among them, 40 (17.9%) were resistant to at least streptomycin, tetracycline, ampicillin, chloramphenicol, cefpodoxime, nalidixic acid, ciprofloxacin, and/or kanamycin despite lacking resistance to azithromycin and meropenem. Moreover, 15 were ESC-resistant Salmonella harboring blaCMY-2 (Salmonella enterica serovar Ohio, n=12; S. Braenderup, n=1; untypeable with O7:b:-, n=1) and blaCTX-M-14 (S. Cerro, n=1). IncA/C2 plasmids containing ISEcp1, IS26, and multiple antimicrobial resistance genes (including blaCMY-2) were identified in S. Ohio isolates from pullet-rearing and layer farms belonging to the same company. Chromosomal integration of partial or whole IncA/C2 plasmids was seen with two S. Ohio isolates via ISEcp1 or IS26, respectively. Antimicrobial resistance genes such as blaCMY-2 might be transmitted among the upper and the lower levels of layer breeding chains via the replicon type IncA/C2 plasmids containing ISEcp1 and IS26.

Detection of Borrelia DNA in Tick Species Collected from Vegetation and Wild Animals in Fukuoka, Japan.

We screened for the presence of Borrelia spp. in ticks collected from vegetation by flagging and from wild animals between May 2017 and November 2018 in Fukuoka, located in the northern Kyushu region of Japan. A total of 1,601 ticks were collected and separated based on morphology into nine species, namely Ixodes turdus, I. ovatus, Amblyomma testudinarium, Haemaphysalis flava, H. formosensis, H. kitaokai, H. longicornis, H. hystricis, and H. megaspinosa. The ticks were segregated into 561 pools and nested PCR was used to detect borrelial DNA. Borrelia turdi and Borrelia sp. HM were identified in two of the 561 pools. This is the first report of the presence of the Lyme disease group of Borrelia and of the relapsing fever group of Borrelia in Fukuoka, Japan.