西沙群岛恙虫病自然疫源地调查研究

Xisha Islands:the Natural Infectious Focus of Tsutsugamushi Disease with Suncus murinus (Main Host)

１９９４年在西沙群岛调查发现，宿主动物以食虫目臭（Ｓｕｎｃｕｓｍａｒｉｎｕｓ）为优势种群，其在永兴岛占９１．３８％，带恙螨指数和带螨率分别为２．６６和４８．８８％，亦最高；恙螨中以作为南方恙虫病主要媒介的地里纤恙螨为优势种，占８６．６５％。血清学试验显示，西沙人群，尤其宿主动物的恙虫病立克次体（Ｒｔ）感染率很高，抗体分型属Ｋａｒｐ、Ｋａｔｏ和Ｇｉｌｌｉａｍ血清型。应用分子流行病学方法──ＰＣＲ技术，检测出媒介恙螨及宿主动物（臭）体内均携带有一定数量的Ｒｔ病原。据西沙驻军医院记载，每年收治有典型恙虫病症状病人３０～４０例，患者秋冬季居多，证实西沙群岛存在以臭为主要宿主动物的恙虫病自然疫源地。

Our investigation in 1994 found that Suncus murinus was the dominative species at Xisha islands. which constituted 91.38% at Yongxing island and carried parasitic chiggers index and rate were 2.66 and 48.88% respectively,the highest record, Among the parasitic chiggers,the Leptoerombidium deliense was the dominative species as the main vector of sourthen Tsutsugamushi disease,making the proportion of 86.65%,Serum tests indicated that Richettsia tsutsugamushi (Rt) of host animals was infected at high rate,especially in Xisha islands population,and the serum types of the antibody were belong to Karp, Kato and Gilliam. The PCR technology of molecular epidemiology ways inspected out that medium parasitic chiggers and Suncus murinus,of host animals carried some Rt pathogens. According to the record of military hospital at Xisha island, 30～40 patients with typical Tsutsugamushi disease symptom were treated every year that happened mainly at autum and winter. This proved completely that Xisha islands be the Tsutsugamasshi disease natural infectious focus with Suncus murinus, the main host animal.