海南岛恙虫病立克次体研究

目的:阐明海南岛恙虫病立克次体的存在及其分布。方法:①恙虫病立克次体血清学调查用微量免疫荧光检测法(mIFA)。②恙虫病立克次体分离用小鼠接种法和L929细胞培养法,恙虫病立克次体鉴定用特异性抗体mIFA。③应用聚合酶链反应(PCR、NPCR)技术检测恙虫病立克次体特异性DNA。④DNA序列。结果:①35份不明原因发热患者血清中,10/35(28.57％)份血清呈IgG抗体阳性反应(滴度≥1:80)。收集自海南岛的东、西、南、北、中部地区的561份人群血清恙虫病立克次体IgG抗体阳性率为13.55％(76/561)。其中东部地区阳性率为8.69％(10/115),南部为7.22％(7/97),西部为28.83％(32/111),北部为11.76％(12/102),中部为11.03％(15/136)。②小白鼠接种分离法从疑似立克次体病患者血液中分离出3株恙虫病立克次体,L929细胞培养法从20份不明原因发热患者血液中分离出3株恙虫病立克次体。③应用PCR技术从9例疑似立克次体感染患者血液中检出4例恙虫病立克次体特异性DNA。用NPCR法从17组野鼠脾脏标本中检出3组恙虫病立克次体特异性DNA。④DNA序列已经分析清楚。结论:海南岛确有恙虫病存在,该岛的中、西部感染率较高,南、北部较低。海南岛恙虫病立克次体DNA序列已分析清楚。

INVESTIGATION OF RICKETTSTIA TSUTSUGAMUSHI ON HAINAN ISLAND

ABSTRACT Objective: To elucidate the existence and distribution of Rickettstia tsutsugamushi in Hainan Island. Method:(1)The indirect microimmunofluorescence(mIFA)test was using for serosurvey of Rickettstia tsutsugamushi. (2)Isolation of Rickettstia tsutsugamushi with mice incubation, and L929 cell culturation. Identification of Rickettstia tsutsugamushi by mIFA using specific antibody. (3)Determi nation of Rickettstia tsutsugamushi specific DNA by PCR and N-PCR. (4)DNA sequence analysis. Re Suits; (1)Among 35 serum specimens were collected from fever unknown organism (FUO)patient ,10 serum specimens were IgG antibody positive reacted with Rickettstia tsutsugamushi (titer≥1 : 80)and 561 serum specimens were collected from outpatients at hospital in eastern,southern,western,northern and center of the island, 76/561 (13.55 %)serum specimens were IgG antibody positive reacted with Rickettstia tsutsugamushi (titer≥1:20) ,the positive number (positive rate) of eastern were 10/115 (8.69%). the southern were 7/97(7.22 %),the western were 32/111(28.83%), the northern were 12/102 (11.76%) and the center were 15/136(11.03%). (2)3 strans of Rickettstia tsutsugamushi were isolated from blood specimens of FUO patients by mice incubation, and 3 strans of Rickettstia tsutsugamushi were isolated from 20 blood specimens of FUO patients by L929 cell culturation. (3)4 cases were detected Rickettstia tsutsugamushi specific DNA from 9 blood specimens of suspected rickettssiosis patients and 3 group were detected specific DNA from 17 group field mouse spleen specimens by NPCR. (4)DNA sequence of Rickettstia tsutsugamushi hainan strain were anerlysis.from DNA extraction. Conclusion: Its confirm that exist of scrub fever on Hainan Island The infective rate is higher in western and center of the island than in southern and northern.And its undestanding that the DNA sequence of Rickettstia tsutsugamushi hainan strain.