副溶血弧菌病原学流行规律以及特征分析

目的对宁波市镇海区腹泻患者副溶血性弧菌(VP)流行病学规律以及特征进行分析,从中发现其病原生物学特性并观察患者发生VP感染的危险因素,为控制VP引起的食物中毒提供参考数据。方法选取2020年1月至2022年2月期间收集腹泻患者粪便标本共515份,共检测出VP菌株共121株(占比23.49%),对VP菌株进行血清分群分析,采用PCR方法对VP菌株中tdh和trh毒力基因进行检测,并完成药敏试验。观察VP感染患者血清分群结果,其毒力基因检测结果及药敏试验结果,观察121例VP感染患者的临床特征,采用二元Logistic回归分析发生VP感染的危险因素。结果121株分离自患者粪便的副溶血性弧菌经血清凝集后显示O3群共97株(占比80.17%),O4群共21株(占比17.36%),O10群发现2株(占比1.65%),O8群发现1株(占比0.83%);121株菌株毒力基因tdh均为阳性,trh均为阴性;VP菌株对氨苄西林(AMP)耐药率最高为85.12%,其他三代头孢菌素、氟喹诺酮类比较敏感分别为100%。收集VP菌株对应患者的临床资料情况,存在87.60%的VP感染患者排泄粪便呈水样,2例患者的排泄粪便样为脓血状,有10例患者伴随腹痛症状,7例患者伴有机体发热症状;临床治疗方面,105例患者(占比86.78%)采用抗生素治疗,85例患者(占比70.25%)采用输液治疗,32例患者(占比26.45%)采用口服用药治疗,6例患者(占比4.96%)采用输液和口服联合用药。结论镇海区VP感染患者中分离株的tdh基因的携带率较高,血清分群多样,VP分离株对多数抗生素敏感,仅对AMP存在较高的耐药率;镇海区后续应加强食品安全监督,对人群展开针对性宣教,对控制本地区VP感染所致腹泻发病具有积极效用。

Objective To analyze the carrying status and infection mechanism of Vibrio parahaemolyticus(VP)in patients with diarrhea in Ningbo area,and to find its pathogenic biological characteristics and observe the risk factors of VP infection in patients,so as to provide reference data for the control of food poisoning caused by VP.Methods A total of 515 intestinal specimens were collected from diarrhea patients from January 2020 to February 2022,and a total of 121 VP strains(23.49%)were detected.Serum group analysis was conducted for VP strains,PCR method was used to detect TDH and TRH virulence genes in VP strains,and drug sensitivity test was completed.The results of serum classification,virulence gene detection and drug sensitivity test of patients with VP infection were observed.The clinical characteristics of 121 patients with VP infection were observed,and the risk factors of VP infection were analyzed by binary Logistic regression.Results After serum agglutination of 121 vibrio parahaemolyticus isolates from feces of patients,97(80.17%)were found in O3 group,21(17.36%)in O4 group,2(1.65%)in O10 group and 1(0.83%)in O8 group.All 121 strains were positive for tdh and negative for trh.VP strain had the highest resistance rate to ampicillin(AMP),which was 85.12%.The clinical data of patients corresponding to VP strain were collected,and stool excretion was watery in 87.60%of patients with VP infection,pus and blood in 2 patients,abdominal pain in 10 patients,and fever in 7 patients.In clinical treatment,105 patients(86.78%)were treated with antibiotics,85 patients(70.25%)were treated with infusion,32 patients(26.45%)were treated with oral infusion,and 6 patients(4.96%)were treated with combination of infusion and oral administration.Binary Logistic regression analysis showed that the age range of monitoring cases was 20~59 years,monitoring months were from May to October,and eating aquatic food was a risk factor for VP infection in the monitoring cases of foodborne diseases,with statistical significance(P<0.05).Conclusion The tdh gene carrying rate of isolates from VP infected patients in Ningbo area is high,and the serum population is diverse.VP isolates are not resistant to most antibiotics,but has a high drug resistance rate to AMP.Food safety supervision should be strengthened in Ningbo in the future,and the quality of monitoring work still needs to be improved.Moreover,targeted propaganda and education for vulnerable populations has positive effect on the control of diarrhea caused by VP infection in this region.