2021—2022年上海市金山区人源与禽源空肠弯曲菌的耐药性及多位点序列分型

Drug resistance and MLST of Campylobacter jejuni from human and avian sources in Jinshan District of Shanghai from 2021 to 2022

【目的】了解上海市金山区人源与禽源空肠弯曲菌的耐药性现状及多位点序列分型(MLST)情况。【方法】收集2021—2022年金山区腹泻患者的粪便样品,采集金山区2家禽类养殖场禽类及相关样品进行空肠弯曲菌检测,对检出空肠弯曲菌进行微量肉汤稀释法药敏试验测定最小抑菌浓度(MIC),并选取部分菌株进行全基因组测序和MLST分析。【结果】共收集腹泻病样品823件,检出空肠弯曲菌32株,检出率3.89%。禽类相关样品600件,检出空肠弯曲菌62株,检出率10.33%。人源多重耐药达93.75%(30/32),禽源多重耐药达100.00%(62/62)。人源与禽源空肠弯曲菌耐药率排名前4位分别为阿奇霉素(人源100.00%、禽源100.00%),萘啶酸(人源93.75%、禽源87.10%),环丙沙星(人源90.63%、禽源98.39%),四环素(人源84.38%、禽源98.39%)。人源空肠弯曲菌中耐药性相对较低者为红霉素、氯霉素、泰利霉素。禽源空肠弯曲菌中耐药性相对较低者为红霉素、克林霉素、氟苯尼考。MLST分析显示选取的16株菌分为9种ST型,其中禽源空肠弯曲菌进化关系比较集中,人源空肠弯曲菌比较分散。且发现1株禽源空肠弯曲菌与2株人源空肠弯曲菌有较近的亲缘关系。【结论】该地区腹泻病患者中空肠弯曲菌感染严重,检出率仅次于沙门氏菌及副溶血性弧菌。禽源空肠弯曲菌感染比较普遍,两者耐药均较严重,应该加强监测与控制。MLST分析显示禽源与人源空肠弯曲菌均出现新序列型别,说明出现新的变异,须持续监测,避免新菌株的出现而引起流行。禽源与人源出现亲缘关系较近的分离株,揭示空肠弯曲菌从禽向人传播的证据,应该加强养殖场相关样品的空肠弯曲菌监测。

[Objective]To understand the current drug resistance status and bacterial multilocus sequence typing(MLST)of human and avian Campylobacter jejuni in Jinshan District,Shanghai.[Methods]Fecal samples were collected from diarrhea patients in the annuity mountainous area from 2021 to 2022,and poultry and related samples were collected from 2 poultry farms in the Jinshan area for detection of C.jejuni.Minimal inhibitory concentration(MIC)drug sensitivity test was performed on the detected C.jejuni,and some strains were selected for whole genome sequencing and MLST analysis.[Results]A total of 823 samples of diarrhea disease were collected,and 32 strains of C.jejuni were detected,with a detection rate of 3.89%.Out of 600 poultry related samples,62 strains of C.jejuni were detected,with a detection rate of 10.33%.Human multidrug resistance reached 93.75%(30/32),while avian multidrug resistance reached 100.00%(62/62).The top four drug resistance rates of human and avian C.jejuni were azithromycin(100.00%from humans and 100.00%from birds),naphthoic acid(93.75%from humans and 87.10%from birds),ciprofloxacin(90.63%from humans and 98.39%from birds),and tetracycline(84.38%from humans and 98.39%from birds).The relatively low resistance strains of human derived C.were erythromycin,chloramphenicol,and thalithromycin.The relatively low resistance strains of avian C.jejuni were erythromycin,clindamycin,and flufenicol.MLST analysis showed that the selected 16 strains of bacteria were divided into 9 ST types,among which the evolutionary relationship of avian C.jejuni was relatively concentrated,while human C.jejuni was relatively dispersed.It was found that one strain of avian C.jejuni was closely related to two strains of human C.jejuni.[Conclusions]C.jejuni infection is severe in patients with diarrhea in this region,with a detection rate second only to salmonella and Vibrio parahaemolyticus.C.jejuni infection in poultry is relatively common,and both are highly resistant.Therefore,monitoring and control should be strengthened.MLST analysis shows new ST types in both avian and human sources of C.jejuni,indicating the emergence of new mutations that require continuous monitoring to avoid the epidemics caused by new strains.The isolated strains with close genetic relationships between avian and human sources reveal the evidence of the spread of C.jejuni from poultry to humans.Therefore it is necessary to strengthen the monitoring of C.jejuni in relevant samples from breeding farms.