目的 调查蚋叮咬的原因，为防治蚋提供科学依据。方法 运用流行病学方法询问病史及进行现场调查；2016年6月8日采用人诱停落法捕获昆虫并对其进行形态学鉴定。结果 该叮人昆虫经鉴定为双翅目蚋；蓝莓园附近的稻田是蚋的孳生场所，人工停落法监测5 min捕获13只；在蚋的孳生场所，11人因暴露下肢皮肤而全部被叮咬；主要叮咬部位是小腿、脚踝和足背，表现为剧烈瘙痒、疼痛和红肿，2周左右症状基本消失；叮咬3~20处，下肢皮肤裸露越多，叮咬部位越多；当地居民证实有蚋存在。结论 丽水市庆元县境内有吸血蚋分布；该事件为在蚋孳生场所职工暴露皮肤被叮咬引起；应加强宣传教育，做好防护，游玩和劳作时避开蚋的活动高峰期；加强蚋种群、密度、季节消长、分布及病原体携带情况等的监测，制定综合防治措施。

Objective To determine the real cause of this biting accident and reveal the truth of so-called poisonous mosquitoes, providing scientific evidence for control and prevention. Methods Means of epidemiology such as inquiry of medical history, field investigation were used to understand and follow up the bitten patient,and man-induced landing and catching method and identification for insect body morphology were also carried out for qualitative determination. Results The so-called mosquitoes were finally identified as members of Diptera gnats; and no blackfly activities were found anywhere near the scenic spot of Western palace; Besides, the rice field next to a blueberry garden was found to be the breeding environment of them. Actually, the inspecting density of man-induced landing method could get to the level of 13 blackflies/5 min, which caused 11 catching workers were bitten mostly on skin of lower limbs from 3-20 positions by blackflies in breeding environment, and parts of being bitten were nearly at lower limbs, ankles and acrotarsiums, symptoms were mainly characterized by severe itching, pain, redness and swelling, and it dismissed after 2 weeks. Thus, local people could prove the actual existence of blackflies and it was defined that the more lower limbs skin were exposed, the more bitten positions could be. Conclusion It is certain thing that the blackflies are definitely distributed in Qingyuan county of Lishui city, and this biting accident is clearly caused by exposure skin bites in blackfly breeding environment. In accordance, measures like strengthening publicity and education, improving individual protection and avoiding the peak season of insect activities when playing and working should be taken seriously. Moreover, further research on blackfly population, density, seasonal fluctuation, distribution, pathogen infection and understanding the season density of growth and decline, strengthening inspection and establishing comprehensive preventive measures will effectively pave the way for biting reduction by blackflies.