1.Analysis of drug resistance phenotypes and drug resistance genes of Enterococcus faecalis and Enterococcus faecium isolates of human-animal-environment sources from a self-breeding pig farm in Xinjiang
Panpan XIA ; Huimin WU ; Wanzhao CHEN ; Chenhui ZHANG ; Peicong LAN ; Zepeng LIU ; Rui TIAN ; Lining XIA
Chinese Journal of Veterinary Science 2024;44(7):1430-1437
In order to understand the prevalence and antimicrobial resistance of Enterococcus faeca-lis(E.faecalis)and Enterococcus faecium(E.faecium)isolated from human,pig and environ-ment in a Xinjiang pig farm,and to investigate the prevalence and potential harm of antimicrobial resistance genes,858 fecal samples from pig farm workers,anal swabs from pig and environment were collected for isolation,identification,antimicrobial susceptibility test and drug resistance gene detection.The results showed that 429 strains of E.faecalis and 222 strains of E.faecium were i-solated.The distribution of Enterococcus species varied among different sources.The isolation rate of E.faecalis was higher in pig anal swabs(73.1%,309/423)and human fecal samples(68.4%,26/38).E.faecium(42.3%,168/397)was mainly isolated from environmental samples.The drug resistance of E.faecalis and E.faecium isolated from pigs was similar to that of E.faecium isola-ted from environment.The drug resistance rates of E.faecalis and E.faecium isolated from pigs were more serious than those from humans to tetracycline,doxycycline,florfenicol and erythromy-cin,and they were more sensitive to ciprofloxacin and levofloxacin.More than 30.0%of E.faecalis and E.faecium isolated from pigs and environment were intermediate to linezolid.E.faecalis from three sources and E.faecium from environmental sources were mainly resistant to five drugs,while E.faecium from pigs was mainly resistant to six drugs.The detection rates of tet(M)and tet(L)genes in E.faecalis and E.faecium isolates from human,animal and environmental sources were more than 70.0%,which was consistent with the results of drug sensitivity.In addition,the cfr,optrA and poxtA genes that mediate oxazolidinone resistance were detected to varying extent.The cfr gene was only detected in four E.faecalis isolates from swine,one E.faecalis isolate from environment and two E.faecium isolates from environment.The positive rate of optrA gene in E.faecium isolated from pigs and environment was higher than that from humans,and the posi-tive rate was more than 60.0%.The positive rate of poxtA gene in E.faecium isolated from pigs and humans was more than 45.0%.The similar drug resistance situation suggests that there is the phenomenon of mutual contamination of drug-resistant bacteria in human-animal-environment.Therefore,we should consider from the perspective of one health,formulate comprehensive disin-fection and control programs,block the transmission route of drug-resistant strains and drug re-sistance genes between human-animal-environment,standardize the use of antibiotics,and reduce the enrichment of antibiotics in human-animal-environment,so as to reduce the risk of drug-resist-ant bacteria.