云南省中缅边境地区疟疾血清流行病学调查分析

目的 了解中缅边境一线县、二线县、及一线三个县的一线自然村、二线自然村的疟疾流行情况,为制定边境地区疟疾防治措施提供科学依据。方法 采用IFAT对中缅边境沧源、耿马及孟连一线县与双江县、永德县二线县,边境线3县一线自然村和二线自然村进行疟血清流行病学调查,用电脑软件EPI6X2检验法进行数据分析。结果一线县抗体阳性率23.88％（568/2379）,二线县抗体阳性率1.40％（10/712）,一线县显著高于二线县（x2=180.54;P<0.01）。一线县的一线自然村抗体阳性率33.05％（467/1413）,二线自然村抗体阳性率10.46％（101/966）,一线自然村显著高于二线自然村（x2=159.92;P<0.01）。结论IFAT抗体阳性率和阳性GMRT说明靠近边境地带比远离边境的地带疟疾流行更为严重。应加强出入境人员的防治工作,才能控制边境疟病流行。     

间接荧光抗体试验检测日本血吸虫感染家兔血清中特异性抗体水平的动态变化

用尾蚴、雌虫、雄虫和血吸虫感染兔肝组织内虫卵冰冻切片抗原进行间接荧光抗体试验（ＩＦＡＴ），观察日本血吸虫感染家兔血清中特异性抗体的动态变化。抗尾蚴、成虫（雌、雄虫）、虫卵抗体检出的最早时间分别为３ｗｋ、３ｗｋ、４ｗｋ，其抗体滴度高峰分别在感染后７ｗｋ、１０～１２ｗｋ和１０ｗｋ。以抗尾蚴抗体水平最高，抗虫卵抗体次之，抗雌、雄虫抗体较低。这为全面了解感染宿主对血吸虫各期抗原（尾蚴、雌、雄虫、虫卵）的免疫反应及免疫学诊断提供了新的资料     

湖南省基本消灭丝虫病后的监测

目的：探讨自1986年湖南省达到基本消灭丝虫病后该病残存传染源消长规律及传播作用。方法：应用常规方法进行病原学、蚊媒和血清学纵向、横向监测以及流动人口监测，对薄弱环节采取适当的巩固措施。结果：在55个县（市）的横向监测中，末次检出微丝蚴阳性者系于1993年，蚊媒监测已有12年未查见人体幼丝虫感染蚊。血清学（IFAT）监测，平均人群抗体阳性率从1987年的13．15％至1996年降为1．06％，与非流行区人群水平相似。5个县（市）6个纵向监测点连续10－17年的观察结果，检获的11例残存微丝蚴血症者，有10例均在1－10年内阴转，另1例至14年未阴转。蚊媒监测，2个马来丝虫病监测点均未查见幼丝虫，4个班氏丝虫病监测点于第1－3年查见幼丝虫，其自然感染率为0．38％－1．98％，第4年以后均为阴性。结论：湖南省基本消灭丝虫病后残存传染源逐年减少，丝虫病传播已被阻断。     

The immunofluorescence antibody test (IFAT) for the diagnosis of schistosomiasis used in a non-endemic area

OBJECTIVE: To evaluate an immunofluorescence antibody test (IFAT) for diagnosis of schistosomiasis in nonimmune travellers and immigrants from endemic areas. METHODS: 65 patients (48 Danes and 17 immigrants) with schistosomiasis were included. The diagnosis of schistosomiasis was based on the presence of schistosome eggs in faeces, urine, sperm, rectal or bladder biopsies and/or the presence of specific antibodies determined by the serological immunofluorescence antibody test (IFAT). Egg excretion was detected using conventional methods and the IFAT performed on whole S. mansoni schistosomula worms, harvested after 8 weeks from mice. Two patterns of immunofluorescence were observed: Fluorescence in the gut of the schistosome called 'Gut Associated Antigen, GAA', and fluorescence of the surface of the schistosomula called 'Membrane Bound Antigen, MBA'. RESULTS: Eggs were found in 44% of the Danish patients and in 76% of immigrants. The diagnosis was based on a positive IFAT in 48% of the patients. In patients from nonendemic areas, the finding of antibodies against GAA was diagnostic while optimal sensitivity in the immigrants was reached by measuring antibodies against both GAA and MBA. CONCLUSION: In patients from nonendemic areas GAA is a sensitive marker of acute infection with schistosomiasis. In patients from endemic areas the demonstration of both GAA and MBA is necessary to properly identify long-lasting, nonacute infections. Egg-detection and/or measurement of CAA and CCA remain the methods of choice to monitor treatment as the immunofluorescence assay may remain positive for several years after treatment.     

Serodiagnosis of Schistosoma mansoni infections in an endemic area of Burkina Faso: performance of several immunological tests with different parasite antigens

The performance of indirect haemagglutination assays (IHA), enzyme-linked immunosorbent assays (ELISA) and indirect immunofluorescent antibody tests (IFAT) were compared with 450 sera from a Schistosoma mansoni-endemic area in Burkina Faso. All participants in this survey provided at least one sample each of stool, urine and serum. From those with an egg-negative Kato-Katz thick smear, a second stool sample was examined. IHA was based on either extracts of adult S. mansoni worms (SmIHA) or S. japonicum egg antigen (SjIHA). For ELISA, three antigen preparations were used, namely: (i) soluble S. mansoni adult worm antigens (SWAP); (ii) soluble S. mansoni egg antigens (SEA); and (iii) a cationic exchange fraction of S. mansoni eggs (CEF6). IFAT was performed with S. mansoni male worm sections. Among the egg-excretors, the sensitivity of ELISA was high and egg antigens performed slightly better (SEA, 96%; CEF6, 97%) than worm antigen (94%). Sensitivity of IHA was satisfactory with homologous (Sm, >85%), but not heterologous (Sj, 56%) parasite antigen. In IFAT, the parenchyma-associated fluorescence showed high sensitivity (95%), but gut-associated fluorescence, which is known to be a sensitive diagnostic marker for schistosome-infected European travelers, was observed only in 76% of a sub-sample of 100 of the endemic sera. Among sera from egg-negative individuals, many gave positive reactions in several or all of the tests employed. These reactions (formally "false positive") are considered to represent true infections, since chemotherapy had not yet been delivered to this population. For the purpose of further surveys in Burkina Faso or other resource-poor settings, we suggest IHA as an accurate diagnostic test and propose to further improve its performance by including egg rather than worm antigens.     

三种血清学方法对马来丝虫病监测的应用研究

目的：比较三种方法监测马来丝虫病的效果。方法：间接荧光抗体试验（ＩＦＡＴ）、酶联免疫吸附试验（ＥＬＩＳＡ）、斑点－酶联吸附试验（Ｄｏｔ－ＥＬＩＳＡ）。结果：检测１９９０、１９９１、１９９４年基本消灭马来丝虫病的流行区人群血清，ＩＦＡＴ阳性率分别为２４８５％、２０３２％和８３０％；ＥＬＩＳＡ阳性率分别为２１６６％、３０３２％和１５８４％；Ｄｏｔ－ＥＬＩＳＡ阳性率分别为３２５０％、１０９６％和１８８６％；总阳性率分别为４６６６％、３５８０％和３２０７％。结论：以ＩＦＡＴ法较为稳定，３种方法联合应用，可提高阳性率     

Canine leishmaniasis, Italy

We report the results of a survey to determine the prevalence of canine leishmaniasis and the presence of sand flies in northwestern Italy, where autochthonous foci of canine leishmaniasis have not been reported. Active foci of canine leishmaniasis were identified, which suggests that the disease is now also endemic in continental climate areas.     

旋毛虫病人治疗后血清抗体水平的变化

应用旋毛虫幼虫冰冻切片抗原间接荧光抗体试验（ＩＦＡＴ）观察了旋毛虫病人阿苯哒唑治疗后血清抗体水平的变化。结果表明，治疗后抗体阳性率及抗体滴度均比治疗前明显升高，此现象可作为一种治疗有效的客观指标。此外，对旋毛虫病人及时治疗也可将检测到抗体的时间提前１￣２周。旋毛虫病人从治疗后１个月开始抗体水平明显下降，至治疗后４个月时抗体转阴率已达７５％。因此，ＩＦＡＴ对旋毛虫病的近期及远期疗效考核均有一定价值。     

基本消灭班氏丝虫病后的远期监测

本文报道采用海群生对象治疗加流行村全民服药和对象治疗加食用海群生药盐基本消灭班氏丝虫病后的纵向和横向监测结果。两种不同措施基本消灭丝虫病后已监测9－11年，人群微丝蚴率均在逐年下降，前6年仍可检出残存微丝蚴血症者，以后连续5年未再发现微丝蚴阳性，蚊媒调查亦未发现幼丝虫自然感染，IFAT检测人群丝虫抗体阳性率为1．4－5．5％，降至非丝虫病流行区抗体水平，证明丝虫病的传播已被阻断。认为基本消灭班氏丝虫病后监测年限以10年左右为宜，并需连续3年以上未检出微丝蚴血症者和感染蚊，人群丝虫抗体阳性率降至当地非流行区水平，可以确认丝虫病已达到消除。     

华支睾吸虫成虫抗原免疫酶染色试验和间接免疫荧光抗体试验效果的比较

应用成虫冰冻切片抗原作免疫酶染色试验(IEST)及间接免疫荧光抗体试验(IFAT),对比检测了 51份华支睾吸虫病患者和 50份健康人血清,两法的阳性率分别为 92％和 88％;假阳性率分别为 2％和4％,应用 IEST和IFAT对比检查 22份急性血吸虫病患者血清、20份慢性血吸虫病患者血清及 15份并殖吸虫病患者血清。IEST 出现的交叉反应率分别为 14％、5％和0;IFAT出现的交叉反应率分别为 14％、10％和0。表明两法诊断华支睾吸虫病均有较高的敏感性和特异性,并且抗原定位好。而 IEST不需要特殊仪器,更适合于现场应用。