莆田市蝇类与甲乙类肠道传染病相关性及其抗药性特点

Correlations of class A and class B intestinal infectious diseases with flies and their insecticide resistance in Putian,China

目的分析蝇类与甲乙类肠道传染病的相关性,调查莆田市蝇类的抗药性水平以及抗性基因频率。方法用笼诱法监测2019—2022年莆田市蝇类密度,从中国疾病预防控制中心疾病监测信息系统导出甲乙类肠道传染病数据,并用相关性分析二者的关系。采用点滴法、测序和PCR-RFLP(限制性片段长度多态性聚合酶链反应)鉴定抗药性水平以及相关基因型。结果蝇类密度与肠道传染病发病率有一定相关性。莆田市家蝇对毒死蜱表现为敏感,抗性倍数为1.438;对氯菊酯表现出抗性,抗性倍数为8.489。未检测到Vssc(电压门控钠离子通道)基因的突变;CYP6D1v1(细胞色素P450)抗性基因频率为18.57%。结论蝇类密度与甲乙类肠道传染病具有一定相关性,降低蝇类密度有助于减少其发病率。莆田市家蝇对毒死蜱尚未产生抗性,对氯菊酯已产生抗性。

Objective To analyze the correlations between flies and class A and class B intestinal infectious diseases in Putian,China,and to investigate their insecticide resistance and the frequency of resistance alleles.Methods The density of flies in Putian from 2019 to 2022 was monitored by the cage trapping method.Data of class A and class B intestinal infectious diseases were extracted from the Disease Monitoring System of Chinese Center for Disease Control and Prevention.The correlations between fly density and intestinal infectious diseases were investigated.Insecticide resistance level and related genotypes were identified by droplet method,sequencing and PCR-RFLP(restriction fragment length polymorphism polymerase chain reaction).Results A positive correlation was found between the incidence of intestinal infectious diseases and fly density.Houseflies were susceptible to chlorpyrifos but resistant to permethrin,with resistance ratios of 1.438 and 8.489,respectively.No mutation of voltage-gated sodium channel(Vssc)gene was detected,and the frequency of CYP6D1v1(cytochrome P450)resistance gene was 18.57%.Conclusion The incidence of class A and class B intestinal infectious diseases is partly related to fly density,indicating that reduction of fly density is helpful to prevent such diseases.The houseflies from Putian are sensitive to chlorpyrifos but have developed resistance to permethrin.