OBJECTIVE: To investigate the distribution of malaria vector Anopheles in Sichuan Province from 2011 to 2021, so as to provide the scientific evidence for improving the surveillance of malaria vector Anopheles and preventing re-establishment of imported malaria in Sichuan Province.
METHODS: The density and species of Anopheles mosquitoes were investigated using human-bait trapping and light trapping techniques in malaria vector surveillance sites of Sichuan Province from 2011 to 2021. The number, population and density of captured Anopheles mosquitoes were collected and descriptively analyzed, and the geographical distribution map of malaria vectors was plotted using the software ArcGIS 10.7 in Sichuan Province.
RESULTS: A total of 152 243 Anopheles mosquitoes were captured in malaria vector surveillance sites of Sichuan Province from 2011 to 2021, including 150 987 An. sinensis (99.18%) and 1 256 An. anthropophagus (0.82%), and no other Anopheles species were captured. The annual densities of An. sinensis and An. anthropophagus were 0.64 to 1.27 mosquitoes/(person-hour) and 0 to 0.07 mosquitoes/(person-hour) by the human-bait trapping technique, and 6.46 to 26.50 mosquitoes/(light-night) and 0 to 0.82 mosquitoes/(light-night) by the light trapping technique in malaria vector surveillance sites of Sichuan Province from 2011 to 2021. A relatively higher density of An. anthropophagus was seen in Renshou County, Jianyang City, Weiyuan County and Mabian Yi Autonomous County [> 0.40 mosquitoes/(person-hour)] by the human-bait trapping technique, and in Cuiping District and Gaoxian County in Yibin City [> 1.00 mosquito/(light-night)] by the light trapping technique in Sichuan Province from 2011 to 2018, with no An. anthropophagus captured from 2019 to 2021, and a relatively higher density of An. sinensis was detected in Emeishan City, Lushan County, Luojiang District, Tongchuan District and Zhaohua District [> 4.00 mosquitoes/(person-hour)] by the human-bait trapping technique, and in Huili County, Yuexi County, Dechang County, Langzhong City, Pingchang County and Xuanhan County [> 40.00 mosquitoes/(light-night)] by the light trapping technique in Sichuan Province from 2011 to 2021.
CONCLUSIONS: Malaria vectors were still widespread in Sichuan Province from 2011 to 2021, and An. sinensis was the dominant species of malaria vectors. There is still a risk of local re-establishment of imported malaria in Sichuan Province, and it is needed to continue to improve the surveillance of imported malaria cases and malaria vectors.
[摘要] 目的 分析2011—2021年四川省传疟媒介按蚊分布, 为进一步提高传疟媒介按蚊监测质量、制定防止输入性 疟疾再传播措施提供科学依据。方法 2011—2021年, 于四川省传疟媒介监测点分别采用人诱法和灯诱法开展按蚊密 度及种群调查, 对按蚊捕获数量、种群及密度等进行描述性统计分析, 采用ArcGIS 10.7软件绘制四川省传疟媒介分布 图。结果 2011—2021年, 四川省传疟媒介监测点累计捕获按蚊152 243只, 其中中华按蚊150 987只 (占99.18%)、嗜人 按蚊1 256只 (占0.82%), 未捕获其他按蚊。2011—2021年, 四川省传疟媒介监测点采用人诱法调查发现, 中华按蚊年密 度为0.64 ~ 1.27只/(人·h)、嗜人按蚊年密度为0 ~ 0.07只/(人·h); 采用灯诱法调查发现, 中华按蚊年密度为6.46 ~ 26.50 只/(灯·夜)、嗜人按蚊年密度为0 ~ 0.82只/(灯·夜)。2011—2018年采用人诱法调查发现, 仁寿县、简阳市、威远县和马边 彝族自治县嗜人按蚊密度较高[> 0.40只/(人·h)]; 采用灯诱法调查发现, 宜宾市翠屏区和高县嗜人按蚊密度较高[> 1.00 只/(灯·夜)]; 2019—2021年未捕获嗜人按蚊。2011—2021年采用人诱法调查发现, 峨眉山市、芦山县、罗江区、通川区和 昭化区等5个监测点中华按蚊密度较高[均> 4.00只/(人·h)]; 采用灯诱法调查发现, 会理县、越西县、德昌县、阆中市、平 昌县和宣汉县等6个监测点中华按蚊密度较高[均> 40.00只/(灯·夜)]。结论 2011—2021年, 四川省传疟媒介依然广 泛分布, 中华按蚊为传疟优势按蚊; 输入性疟疾引起本地再传播风险依然存在, 需持续加强四川省输入性疟疾病例及传 疟媒介监测工作。.