宁波市鄞州区食源性腹泻患者产气荚膜梭菌感染情况调查

Status of Clostridium perfringens infection in patients with foodborne diarrhea in Yinzhou District,Ningbo City

目的了解宁波市鄞州区食源性腹泻患者产气荚膜梭菌感染状况,为预防控制工作提供依据。方法采集宁波市鄞州区食源性腹泻监测点患者临床粪便标本,直接提取粪便基因组DNA,用荧光定量PCR检测产气荚膜梭菌cpa基因,阳性标本检测cpe、cpb2基因,以cpa阳性作为产气荚膜梭菌感染指标,分析不同特征食源性腹泻患者产气荚膜梭菌检出情况以及与其他食源性腹泻病原体混合感染状况。结果534份标本中共检出产气荚膜梭菌cpa基因99份,检出率18.54%,cpa阳性标本的cpe、cpb2检出率分别为15.15%和78.79%;不同性别的食源性腹泻患者其产气荚膜梭菌检出率差异无统计学意义(χ^(2)=2.765,P>0.05),但随年龄增大检出率呈下降趋势(χ趋势2=12.277,P<0.001);产气荚膜梭菌引起的食源性腹泻全年好发,各月间检出率未见差异(χ^(2)=6.926,P>0.05);不同可疑暴露食物(χ^(2)=6.856,P>0.05)及食物加工方式(χ^(2)=12.329,P>0.05)引起的食源性腹泻病人的产气荚膜梭菌检出率差异均无统计学意义;检出产气荚膜梭菌的标本中有24份混合感染诺如病毒、轮状病毒、沙门氏菌、副溶血性弧菌等其他食源性病原体。结论产气荚膜梭菌是宁波市鄞州区食源性腹泻的主要病原体之一,存在混合感染的情况,应重视对产气荚膜梭菌的病原学监测及预防。

Objective To understand the infection status of Clostridium perfringens(C.perfringens)in patients with foodborne diarrhea in Yinzhou District of Ningbo City so as to provide a basis for its prevention and control.Methods The clinical fecal samples of patients with foodborne diarrhea in Yinzhou District of Ningbo City were collected,and the genomic DNA was extracted directly.Fluorescence quantitative PCR was used to detect the cpa-gene of C.perfringens,and then we detected the cpe and cpb2 genes in positive samples.The cpa-positive was used as the indicator of C.perfringens infection.We analyzed the status of C.perfringens detection and its co-infection with other foodborne diarrhea pathogens in patients with different characteristics of foodborne diarrhea.Results A total of 99 samples of C.perfringens cpa gene were detected in 534 samples(18.54%,99/534),and the detection rates of cpe and cpb2 in cpa-positive samples were 15.15%and 78.79%respectively.No statistically significant difference was found in the detection rate of C.perfringens between male and female patients with foodborne diarrhea(χ^(2)=2.765,P>0.05),but the detection rate showed a downward trend with the increasing age(χ^(2)t rend2=12.277,P<0.001).Foodborne diarrhea caused by C.perfringens was common throughout the year,but there was no statistically significant difference in the detection rate among months(χ^(2)=6.926,P>0.05).No statistically significant difference was observed in the detection rate of C.perfringens among patients with foodborne diarrhea caused by different suspected exposure foods(χ^(2)=6.856,P>0.05)and food processing methods(χ^(2)=12.329,P>0.05).Among the C.perfringens positive samples detected,24 samples were co-infected with norovirus,rotavirus,Salmonella,Vibrio parahaemolyticus and other foodborne pathogens.Conclusion C.perfringens is one of the main pathogens of foodborne diarrhea in Yinzhou District of Ningbo City,and there is mixed infection.Special attention should be paid to the etiological surveillance and prevention of C.perfringens.