Antimicrobial resistance and plasmid-mediated colistin resistance mechanism of diarrheagenic Escherichia coli recovered from foods in parts of China in 2020 / 中华预防医学杂志

Objective: To investigate the antimicrobial resistance of food-borne diarrheagenic Escherichia coli (DEC) and the prevalence of mcr genes that mediates mobile colistin resistance in parts of China, 2020. Methods: For 91 DEC isolates recovered from food sources collected from Fujian province, Hebei province, Inner Mongolia Autonomous Region and Shanghai city in 2020, Vitek2 Compact biochemical identification and antimicrobial susceptibility testing platform was used for the detection of antimicrobial susceptibility testing (AST) against to 18 kinds of antimicrobial compounds belonging to 9 categories, and multi-polymerase chain reaction (mPCR) was used to detect the mcr-1-mcr-9 genes, then a further AST, whole genome sequencing (WGS) and bioinformatics analysis were platformed for these DEC isolates which were PCR positive for mcr genes. Results: Seventy in 91 isolates showed different antimicrobial resistance levels to the drugs tested with a resistance rate of 76.92%. The isolates showed the highest antimicrobial resistance rates to ampicillin (69.23%, 63/91) and trimethoprim-sulfamethoxazole (59.34%, 54/91), respectively. The multiple drug-resistant rate was 47.25% (43/91). Two mcr-1 gene and ESBL (extended-spectrum beta-lactamase) positive EAEC (enteroaggregative Escherichia coli) strains were detected. One of them was identified as serotype of O11:H6, which showed a resistance profile to 25 tested drugs referring to 10 classes, and 38 drug resistance genes were predicted by genome analysis. The other one was O16:H48 serotype, which was resistant to 21 tested drugs belonging to 7 classes and carried a new variant of mcr-1 gene (mcr-1.35). Conclusion: An overall high-level antimicrobial resistance was found among foodborne DEC isolates recovered from parts of China in 2020, and so was the MDR (multi-drug resistance) condition. MDR strains carrying multiple resistance genes such as mcr-1 gene were detected, and a new variant of mcr-1 gene was also found. It is necessary to continue with a dynamic monitoring on DEC contamination and an ongoing research into antimicrobial resistance mechanisms.

Differences on ethical consciousness issues between the Chinese Journal of Epidemiology and the American Journal of Epidemiology / 中华流行病学杂志

To compare the differences on current ethical issues in the areas of epidemiological practice between China and America,to identify the major ethical problems existing in the epidemiological studies in China.Through searching and reviewing papers published on Chinese Journal of Epidemiology and American Journal of Epidemiology from Jan.2006 to Dec.2010,we made a comparison on ethical issues involved in the original studies that focusing on human beings.In total,749 Chinese articles and 1221 American articles were recruited,with the following findings: (1)The proportion with announcements of “Informed consent by the subjects” was 29.24％ in Chinese literature and 38.08％ in the Americans (x2=16.02,P＜0.001 ).The proportion with “having had approvals from the ethic committees” was 29.24％ in Chinese,while 38.08％ in American ( x2=604.40,P＜ 0.0001 ).(2) Both in China and America,there had been an increase of ethical issues in the last 5 years.(3)Articles derived from trial studies had better involvement on ethics than those from observational studies.(4) The level on ethical issues in the American Research Institutes exceeded those in China (5)American studies also had showed better ideas on Ethic issues on biological specimens collection and privacy protection,than those in Chinese studies.Among the studies on Chinese Journal of Epidemiology,the proportion of ‘informed consent' was higher than in ethical review,but both ethical review and awareness on ‘informed consent' had left far behind than the American Journal of Epidemiology.This could be seen at the institution level of the writers,during specimen collection and privacy protection,as well as at the overall level.The results reminded us that the Departments of Technology Management should spend more efforts on the improvement of public education regarding ethics for researchers and to update the process of edition for Journals as well as to reinforce the rules of ethics in epidemiological research.