中国寄生虫学与寄生虫病杂志 ›› 2022, Vol. 40 ›› Issue (4): 481-486.doi: 10.12140/j.issn.1000-7423.2022.04.010

• 论著 • 上一篇    下一篇

2020年河南省内脏利什曼病病例的流行病学调查

杨成运*(), 贺志权, 鲁德领, 钱丹, 刘颖, 李素华, 周瑞敏, 邓艳, 张红卫, 王昊, 赵东阳, 郭万申   

  1. 河南省疾病预防控制中心寄生虫病预防控制所,河南省传染病病原生物重点实验室,郑州 450016
  • 收稿日期:2021-12-06 修回日期:2022-01-21 出版日期:2022-08-30 发布日期:2022-09-07
  • 通讯作者: 杨成运
  • 作者简介:杨成运(1975-),女,博士,副主任技师,从事寄生虫病防治工作。E-mail: tochyun@163.com
  • 基金资助:
    河南省科技攻关项目(222102310722);河南省医学科技攻关计划联合共建项目(LHGJ20190706)

Epidemiological investigation on cases of visceral leishmaniasis in Henan Province in 2020

YANG Cheng-yun*(), HE Zhi-quan, LU De-ling, QIAN Dan, LIU Ying, LI Su-hua, ZHOU Rui-min, DENG Yan, ZHANG Hong-wei, WANG Hao, ZHAO Dong-yang, GUO Wan-shen   

  1. Center of Disease Control and Prevention of Henan Province;Provincial Key Laboratory for Infectious Disease Prevention and Control,Zhengzhou 450016, China
  • Received:2021-12-06 Revised:2022-01-21 Online:2022-08-30 Published:2022-09-07
  • Contact: YANG Cheng-yun
  • Supported by:
    Science and Technology of Henan Province(222102310722);Joint Project of Medical Science and Technology of Henan Province(LHGJ20190706)

摘要:

目的 了解河南省内脏利什曼病流行现状,为疫情监测和科学防控提供依据。 方法 收集河南省2020年内脏利什曼病疫情资料和病例个案调查资料。以病例为线索,对有本地感染病例的村进行疫点调查和处置。以病例住处为中心,在半径100 m内采集病例家属及邻居的血样,同时采集病例所在自然村所有家犬及流浪犬的血样,用rk39免疫层析试纸条检测人及犬血清抗利什曼原虫抗体。提取病例(由病例报告医院提供)、人群和部分犬的血样DNA,PCR检测利什曼原虫动基体靶基因,对动基体靶基因阳性者再PCR扩增利什曼原虫内转录间隔区1(ITS-1)并测序鉴定虫种。5—9月,在有病例的4个村(引驾沟村、小关村、三宗庙村和胡张沟村)采用人工和灯诱相结合的方法捕捉白蛉,并进行解剖和形态学鉴定。提取雌性中华白蛉DNA,PCR扩增利什曼原虫动基体靶基因,检测白蛉利什曼原虫感染情况。 结果 2020年河南省共报告16例内脏利什曼病病例,年龄最小8个月,最大68岁;13例有发热、全血细胞减少和脾肿大等典型的临床表现;从发病到确诊间隔时间平均为45.3 d,中位数为30 d;16例病例中13例为本地感染病例,3例为外省输入病例。13例本地感染病例中,儿童6例(其中≤2岁儿童4例);分布于郑州市、洛阳市和安阳市的7个县(市、区);发病高峰期为10月至次年5月(占11/13)。共采集风险人群血样376份,血清抗体阳性率为0.5%(2/376),PCR检测结果均为阴性。共采集家犬和流浪犬血样721份,血清抗体阳性率为17.5%(126/721),其中郑州、洛阳和安阳市的犬血清阳性率分别为21.8%(59/271)、15.0% (50/333)和14.5%(17/117),3个市之间的差异无统计学意义(χ2 = 5.569,P > 0.05)。PCR检测99份犬血样,阳性率为36.4%(36/99),其中66份血清抗体阳性犬中,PCR检测的阳性率为54.5%(36/66);33份血清抗体阴性犬的PCR检测结果均为阴性。从病例血样扩增的ITS-1序列与婴儿利什曼原虫序列(GenBank登录号MG041377)的一致性为100%,从阳性犬血样扩增的ITS-1序列与婴儿利什曼原虫序列(GenBank登录号MN648767)的一致性为100%。共捕获白蛉1 115只,分属中华白蛉、鳞喙司蛉和许氏司蛉,对39只雌性中华白蛉进行利什曼原虫动基体靶基因PCR扩增,结果为阴性。 结论 河南省存在由婴儿利什曼原虫感染所致的内脏利什曼病的本地流行,犬利什曼原虫的感染率较高。应加强犬只管理,防止内脏利什曼病进一步扩散。

关键词: 内脏利什曼病, 婴儿利什曼原虫, 流行病学调查, 白蛉, 河南省

Abstract:

Objective To investigate the current endemic status of visceral leishmaniasis in Henan Province and to provide basis for surveillance and scientific control. Methods The visceral leishmaniasis endemicity data and the information from individual cases tracking in Henan Province in 2020 were collected. Based on the reported cases, epidemiological investigations and interventions were carried out in the villages where the local cases were reported. Blood samples were collected from the patients’ family members and neighbours within an area of 100 m radius centered on the patient’s residence, meantime, blood samples were also collected from all domestic and stray dogs in the natural villages where the patients reside. The rk39 immunochromatographic test strip was used to detect serum anti-Leishmania antibody in the samples of villagers and dogs. DNA was extracted from the blood samples of patients (provided by the reporting hospital within 1 week of the case report), villagers and a number of dogs to detect Leishmania kinetoplast target gene by PCR. Then internal transcribed spacer 1 (ITS-1) was amplified and sequenced for those samples with kinetoplast gene positive to identify the species of Leishmania. From May to September, methods of manual capture and light traps were used to collect sandflies in four villages (Yinjiagou, Xiaoguan, Sanzongmiao and Huzhanggou villages) for morphological identificatiobn by dissestion. DNA was extracted from female Phlebotomus chinensis. PCR was performed to detect Leishmania kinetoplast target gene for determining Leishmania infection in the andflies. Results A total of 16 cases of visceral leishmaniasis were reported in Henan Province in 2020. The 16 cases covered the age ranging from 8 months to 68 years old. Thirteen cases had typical clinical symptoms, including fever, pancytopenia, and splenomegaly. The average time and the median time from onset to definitive diagnosis were 45.3 d and 30 d, respectively. Among the 16 cases, 13 were local infections, and 3 were imported cases from other provinces. Among the 13 local cases, 6 cases were children including 4 children less than two years old, who reside in seven countries of Zhengzhou, Luoyang and Anyang. Most infections occurred from October to May of the following year (11/13). A total of 376 blood samples were collected from the residents, the positive rate of rk39 antibody was 0.5% (2/376) and all of the 376 blood samples were negative for PCR test. A total of 721 blood samples were collected from dogs. The positive rate of rk39 antibody was 17.5% (126/721). The positive rates of dogs in Zhengzhou, Luoyang and Anyang were 21.8% (59/271), 15.0% (50/333) and 14.5% (17/117), respectively, with no significant difference among the three cities (χ2 = 5.5693, P > 0.05). PCR was performed on 99 dog samples. The positive rate was 36.4% (36/99). Among the 66 seropositive dogs, 36 were positive by PCR with a positive rate of 54.5% (36/66), while 33 seronegative dogs were all negative in the PCR test. The ITS-1 sequences amplified from the patients had 100% homology with the L. infantum sequence (GenBank accession number MG041377). The ITS-1 sequences amplified from the positive dogs had 100% homology with the L. infantum sequence (GenBank accession number MN648767). A total of 1 115 sandflies were captured and identified as P. chinensis, Sergentomyia khawi and S. squamirostris. Among them, 39 female P. chinensis were negative in PCR detection. Conclusion There exists local transmission of visceral leishmaniasis caused by L. infantum in Henan Province, and the positive rate of canine Leishmania infection in dogs is relatively high. It is necessary to strengthen the management of dogs to prevent further spread of visceral leishmaniasis in Henan Province.

Key words: Visceral leishmaniasis, Leishmania infantum, Epidemiological investigation, Sandfly, Henan Province

中图分类号: