Abstract:

Objective: To investigate the infection of the first leptospirosis patient in Zhoushan in the past 40 years, and to evaluate the potential risks of host animal and local resident infection. Methods: RT-qPCR was used to detect leptospiral nucleic acid in a suspected case, local residents, and host animals (small mammals and pigs) in 2022. The 23S rRNA target gene was amplified by RT-PCR and sequenced to detect the infected genospecies. ELISA was used to detect leptospiral antibodies in the sera of suspected case and residents. Results: Leptospiral nucleic acid was tested positive in the acute phase of the suspected patient, but turned negative in the recovery phase. In contrast, IgM and IgG were negative in acute phase but positive in recovery phase. Leptospiral nucleic acid was tested negative in the sera of 69 residents, but was positive in the urine of 3 residents with positive IgM. The positive rate of IgM in sera of residents was 4.35% (3/69) and the positive rate of IgG was 8.70% (6/69). The positive rate of leptospiral nucleic acid in small mammal kidney was 30.00% (15/50), and the three pig urine were positive for leptospiral nucleic acid. The species in the sera of the suspected case in acute phase, 4 rat kidney specimens, and 2 pig urine specimens were identified as Leptospira borgpetersenii. The species in 3 urine specimens from local residents, 5 rat kidney specimens, and 1 pig urine specimen were identified as L. interrogans. Conclusions: The patient was confirmed with leptospirosis. The infection rates of Leptospira in host animals and residents were both high in the patient's place of residence.

Key words: Leptospirosis, Case identification, Host animal surveillance, Population infection survey

摘要：

目的: 了解浙江省舟山市近40年来首例钩端螺旋体（钩体）患者的感染情况，评估其居住周边环境中的宿主动物及居民感染状况。方法: 应用反转录实时荧光定量PCR（RT-qPCR）方法对2022年1例钩体病疑似病例、其居住地周围居民以及宿主动物（小兽、猪）进行钩体核酸检测，采用反转录PCR扩增23S rRNA靶基因并测序，分析感染基因种。利用酶联免疫吸附试验方法对疑似病例和周围居民进行血清钩体抗体检测。结果: 疑似病例急性期血清钩体核酸阳性，IgM与IgG均阴性；恢复期血清钩体核酸阴性，IgM与IgG均阳性。居住地周围69名居民血清钩体核酸均为阴性，IgM和IgG阳性率分别为4.35%（3/69）和8.70%（6/69），其中3份IgM阳性居民的尿液钩体核酸均为阳性。小兽肾钩体核酸阳性率为30.00%（15/50），3份猪尿钩体核酸均为阳性。23S rRNA基因测序结果显示：该疑似病例急性期血清、4份鼠肾及2份猪尿样本为博氏钩体；3份居民尿液、5份鼠肾及1份猪尿样本为问号钩体。结论: 该疑似病例可确诊为钩体病。患者居住地的宿主动物和周围居民均有较高的钩体感染率。

关键词: 钩端螺旋体病, 病例鉴定, 宿主动物监测, 人群感染调查