Shedding of OXA-181 carbapenemase-producingfrom companion animals after hospitalisation in Switzerland: an outbreak in 2018.

Abstract

BackgroundCarbapenem-resistant Enterobacteriaceae pose a serious threat to public health worldwide, and the role of companion animals as a reservoir is still unclear.AimsThis 4-month prospective observational study evaluated carriage of carbapenem-resistant Enterobacteriaceae at admission and after hospitalisation in a large referral hospital for companion animals in Switzerland.MethodsRectal swabs of dogs and cats expected to be hospitalised for at least 48 h were taken from May to August 2018 and analysed for the presence of carbapenem-resistant Enterobacteriaceae using selective agar plates. Resistant isolates were further characterised analysing whole genome sequences for resistance gene and plasmid identification, and ad hoc core genome multilocus sequence typing.ResultsThis study revealed nosocomial acquisition ofharbouring the carbapenemase gene, the pAmpC cephalosporinase geneas well as quinolone resistance associated withand mutations in the topoisomerases II (GyrA) and IV (ParC). Theandgenes were identified on a 51 kb IncX3 plasmid andon a 47 kb IncI1 plasmid. All isolates belonged to sequence type ST410 and were genetically highly related. Thisclone was detected in 17 of 100 dogs and four of 34 cats after hospitalisation (21.6%), only one of the tested animals having tested positive at admission (0.75%). Two positive animals were still carriers 4 months after hospital discharge, but were negative after 6 months.ConclusionsCompanion animals may acquire carbapenemase-producingduring hospitalisation, posing the risk of further dissemination to the animal and human population and to the environment.