青海省自1954年开始鼠疫自然疫源地调查，截止1997年，已发现10种鼠疫菌染疫昆虫（斧形盖蚤、谢氏山蚤、腹窦纤蚤深广亚种、圆指额蚤、红羊新蚤、具钩靴片蚤、人蚤、草原硬蜱、血红扇头蜱、古北拟颚虱），其中斧形盖蚤和谢氏山蚤的检菌率高，分别占昆虫检菌总数的42．1％和23．6％。由蚤叮咬引起的12起人间鼠疫中，以18岁以下年龄组发病率高。 Since 1954, Qinghai Province has investigated the plague natural foci. As of 1997, 10 species of plague plague have been found to have contracted the mosquitoes (Chestnut flea, Sheep flea, Apodemus divaricatus, New fleas of red sheep, fleecans with fleece hook, flea flea, Ixodes latifolia, Myrmetoides sylvestris, Paleopigus citri), of which, 42.1% and 23.6% of the total number of bacteria. Of the 12 human plague cases caused by fleas bites, the incidence was high in the age group of 18 years or younger.