云南省勐海县居民粪类圆线虫感染调查

采用Koga法、Bearmann法、改良加藤氏法对勐海县居民进行粪检，250人中检出粪类圆线虫感染29人，感染率11．60％。采用改良加藤厚涂片法检查254人，虫卵阳性248人，阳性率97．63％。蛔虫、钩虫、鞭虫感染率分别89．76％、70．08％和82．68％。     

粪类圆线虫和钩虫感染的诊断:粪便和十二指肠液检查效果的比较

粪便镜检粪类圆线虫和钩虫的敏感性不高。即使粪类圆线虫和钩虫的幼虫或虫卵密集在十二指肠液或空肠液中,也不一定能在粪便中查到。所以,对粪便和十二指肠液检查上述寄生虫的敏感性进行了对比研究。于1981年6月～1985年5月,将印度Vellore地区因胃肠道症状而住院的292名病人列为研究对象。于特殊治疗前,所有病人     

Kato-Katz法2送6检结合粪孵法用于血吸虫病现场筛查

目的探讨敏感性、准确性较高的血吸虫病病原学检查新方法。方法以血吸虫病流行区湖北省武汉市汉南区捞子湖村居民为对象,连续2d每天收集1次新鲜粪便样本,并采用加藤厚涂片法（Kato-Katz法）顺序制作6张涂片,检测粪便中血吸虫卵（2送6检）;对检测阴性者再采用尼龙绢集卵孵化法对粪便样本复检,进行阳性检出率和克粪虫卵数（EPG）值的比较。同时收集相关的流行病学基础资料。结果 Kato-Katz法共检测562人,阳性67例;对Kato-Katz法检测阴性的495人进行粪孵法复检,阳性6例;两法检出总阳性者73例。以阳性病人73例计算,Kato-Katz法1送3检累计阳性为48例,累计阳性率为65.8%,漏检率为34.25%,2送6检累计阳性为67例,累计阳性率为91.8%,漏检率为8.22%,随着检测次数的增加,阳性检出率逐渐升高。6次累计阳性率比单次平均阳性率提高53.50%。病人EPG几何均数1～6片分别为61.12、31.92、23.71、20.88、19.35和18.83,显示涂片数较少时病人EPG偏高,病人EPG的准确性随涂片数增加而提高。结论为获得较高的血吸虫病检出率和准确的人群感染度,Kato-Katz法2送6检结合粪孵法值得应用。     

一例粪类圆线虫感染的形态学和分子生物学诊断

目的 采用形态学特征结合分子生物学方法及时确诊粪类圆线虫感染。 方法 对患者粪便中的 线状虫体进行形态学观察,随后提取虫体 ＤＮＡ,通过 ＰＣＲ 法检测虫体鉴别分子 ＣＯＸ１ 及 １８Ｓ ｒＲＮＡ,对产物 进行测序比对,鉴别虫体。 结果 形态学观察发现该虫体呈线性,半透明,尾部短,一端较钝,一端尖细,与犬 弓蛔虫、狮弓蛔虫、毛圆线虫属、钩虫及人蛔虫的幼虫相似。 ＰＣＲ 检测出粪类圆线虫 ＣＯＸ１ 及 １８Ｓ ｒＲＮＡ 阳 性条带。 对扩增产物进一步测序并比对,结果确定该虫体为粪类圆线虫。 结论 形态学特征观察结合分子 生物学方法可以确诊粪类圆线虫感染,为临床及时治疗提供帮助。     

母乳传染人体美洲钩虫的观察

海豹、猪、马、牛、猫和鼠的寄生线虫幼虫通过母乳传染已有报道。人的乳汁内查见旋毛虫幼虫和粪类圆线虫第3期幼虫以及在乳头切片内发现班氏微丝蚴的事例也曾有报告。本文作者对128名产妇第1～10天的初乳1～100ml,经蒸馏水稀释,以2,500rpm离心5分钟。吸除乳脂,弃去上清液,再用蒸馏水10ml稀释沉淀物离心一次。然后镜检沉渣悬液,同时检查母亲和婴儿的新鲜粪便。结果产妇的粪检钩虫阳性率为61%,而婴儿无一例受染。阳性患者用甲苯咪唑驱出的虫体均为美洲钩虫。乳汁检查仅在1例产后第4天的一个样品中发现活动的第3期幼     

青霉素瓶定量饱和盐水漂浮法与Kato-Katz法检查钩虫卵的比较研究

目的青霉素瓶定量饱和盐水漂浮法和Kato-Katz法对钩虫卵检出的效果比较。方法与结果用青霉素瓶定量饱和盐水飘法和Kato-Katz法双盲检测487例居民粪样,两法的钩虫卵阳性检出率分别为28.54％和26.08％,差异无显著意义(P>0.05)。两法联合使用的总阳性度为35.73％,较两法单用分别提高了7.19％和9.65％,表明两法有互补作用,可以结合使用。对钩虫感染度的估计,当EPG≤100时,定量漂浮法与Kato-Katz法相当(P>0.05),但对EPG>100的粪便定量漂浮法估计过低。结论饱和盐水飘浮法更适于轻感染病例的虫卵定量检查。     

日本血吸虫病常用诊断方法应用价值的评估Ⅲ Kato-Katz法低估疫区人群血吸虫感染率的分析与评价

目的现场评估KatoKatz法不同检测粪样次数和涂片数的居民血吸虫感染检出率与低估率。方法采用＂3检27片＂Kato-Katz法对鄱阳湖区1个血吸虫病流行村人群进行连续3年的粪检,并以此为金标准,评估不同检测粪样数和Kato-Katz片数的血吸虫感染检出率与低估率。结果血吸虫感染的检出率随粪检Kato片数的增加而增加,低估率则逐渐降低。1检3片Kato-Katz法对人群感染的低估率达40.98%～50.80%,即使增加到6张Kato片,低估率仍为30%左右（25.48%～32.39%）。观察区人群2008-2010年的粪检阳性率分别为10.96%、8.54%和3.73%,各年间差异较大,但各Kato片的低估率接近。1检3片、6片、9片法分别和3检3片、6片、9片法的阳性率之间,2检6片与1检6片、3检6片法的阳性率差异均无统计学意义。结论在相同Kato片检测数下,血吸虫感染者的阳性检出率主要取决于Kato片数而不是粪检次数。在血吸虫病低流行状态下,＂1检3片＂KatoKatz法对血吸虫病疫情的低估率较大。为提高KatoKatz法敏感性,宜首先考虑增加Kato片数而不是粪检次数。     

四种粪检方法对肠道线虫感染的检出效果比较

1 材料与方法在江苏省兴化市荻垛乡西茆村对1周岁以上居民进行粪检,共对比检查161人。每份粪样分别作直接涂片(取粪约5mg),Kato-Katz法(定量板取粪41.7mg,常规检查1片),饱和盐水浮聚法(金属圈取粪样500mg,镜检1片)和钩蚴培养法(试管滤纸法)检查,发现虫卵和钩虫幼虫判为阳性。Ka-to’s法作定量计算,每片虫卵数乘以23.98即为克粪虫卵数(EPG)。 2 结果肠道线虫总感染率为81.4％(131/161)。其中蛔虫、钩虫、鞭虫的感染率分别为52.2％(84/161)、59.0％(95/161)、21.1％(34/161)。平均EPG     

唐山市农村小学生肠道致病原感染情况调查

采用随机方法确定唐山市农村小学生肠道致病原感染调查的调查学校和调查对象,采集粪样,用生理盐水涂片法、碘液涂片法、饱和盐水浮聚法检查肠道寄生虫,同时检查肠道致病菌。调查对象共433人,433份粪样中仅检出3例粪类圆线虫和2例结肠内阿米巴;肠道致病菌阳性101份,阳性率为22.75%,其中产碱杆菌阳性5例,乙型副伤寒杆菌阳性78例,伤寒杆菌阳性6例,痢疾杆菌阳性7例,其他5例。唐山市农村小学生肠道寄生虫感染率较低,但是肠道致病菌的感染率较高。     

丙硫苯咪唑治疗肠道线虫病的初步结果

作者用随机,双育试验对非洲马里和塞内加尔186例肠道线虫病患者进行了治疗观察。男性116例,女性70例。年龄3～75岁,11岁以下儿童55例。91例用丙硫苯咪唑(Albendazole)治疗,95例给予安慰剂作对照。186例中81例患有多种寄生虫病,蛔虫、钩虫及鞭虫感染者分别有76、93及78例;此外,18例有粪类圆线虫感染,7例绦虫感染。治前用加藤氏法检查粪便,计算每克粪便内的虫卵数;检查粪类圆线虫采用Harada-Mori氏法。治后7天、21天对患者进行复查。     

Extensive multiparasitism in a village of Yunnan province, People's Republic of China, revealed by a suite of diagnostic methods

Intestinal multiparasitism, the accuracy of different diagnostic techniques, and the influence of sampling effort were studied among 215 individuals in a Bulang village, Yunnan province, People's Republic of China. Behavioral, demographic, and socioeconomic data were obtained by questionnaire. Multiple stool specimens were examined by the Kato-Katz, Koga agar plate, Baermann, and ether-concentration methods. Eight helminth and 7 protozoa species were diagnosed. The prevalence of each of the 3 main soil-transmitted helminths (Ascaris lumbricoides, hookworm, and Trichuris trichiura) exceeded 85%. Blastocystis hominis was the most prevalent intestinal protozoan (20.0%). Over 80% of the individuals harbored 3 or more intestinal parasites concurrently. The infection intensities were predominantly light for hookworm and T. trichiura but moderate for A. lumbricoides. Examination of 3 instead of 1 stool specimen increased the sensitivity of helminth diagnosis, most notably for hookworm. Intestinal multiparasitism is rampant in this rural part of Yunnan province and calls for control measures.     

An epidemiological survey on intestinal parasite infection in Khammouane Province, Lao PDR, with special reference to Strongyloides infection

To estimate the current prevalence of intestinal helminth infection in Lao PDR, a parasitological survey was conducted in three villages in Khammouane Province in December 1996, with special reference to Strongyloides infection. A total of 669 fecal samples were collected in the villages and examined by agar-plate culture method and Kato-Katz thick smear method. Intestinal helminths were demonstrated in 82% of the samples as follows: Ascaris lumbricoides (30.5%), Trichuris trichiura (23.7%), hookworm (28.8%), Strongyloides stercoralis (19.0%), Enterobius vermicuralis (3.4%), Opisthorchis viverrini (56.7%) and Taenia sp (3.0%). The infection rates of S. stercoralis were 27.5% and 18.4% in two rural villages, but only 9.4% in an urban village. The highest prevalence rate of Strongyloides infection was obtained in the age group from 20 to 29 years old, although the infection rate already reached 10% in the age group under 10 years old. The prevalence was consistently higher in male subject than females in almost all age groups.     

Seroepidemiology of strongyloidiasis in the Peruvian Amazon

A stool and serosurvey for Strongyloides stercoralis was conducted in a community in the Peruvian Amazon region. Strongyloidiasis stercoralis was identified in the stool of 69 (8.7%) of 792 participants. Six hundred nine sera were tested using by an enzyme-linked immunosorbent assay (ELISA), which had a sensitivity of 92% and a specificity of 94%; 442 (72%) were positive. In multivariable logistic regression models, having S. stercoralis in stool was associated with hookworm in the same specimen (odds ratio [OR] = 4.44, 95% confidence interval [CI] = 2.02-9.79), occasionally or never wearing shoes (OR = 1.89, 95% CI = 1.10-3.27), and increasing age (OR = 1.012 for each one-year increase, 95% CI = 1.00-1.03). Similarly, occasionally or never wearing shoes (OR = 1.54, 95% CI = 1.01-2.37) and increasing age (OR = 1.04 for each one-year increase, 95% CI = 1.02-1.06) were associated with an increased risk of a positive S. stercoralis ELISA result. The ELISA had a negative predictive value of 98% and is an excellent screening test for strongyloidiasis.     

Increased detection rate of Strongyloides stercoralis by repeated stool examinations using the agar plate culture method

To clarify the efficacy of repeated stool examinations by the agar plate culture method for the detection of Strongyloides stercoralis infection, 4,071 stool samples collected from 2,406 patients > 50 years of age in Ryukyu University Hospital were examined. The cumulative detection rate of S. stercoralis infection was 4.7% (112/2,406). At the first, second, third, and beyond fourth examinations, the detection rates were 3.6% (86/2,406), 1.5% (12/786), 2.6% (10/392), and 2.0% (4/198), respectively. From these results, the cumulative detection rate was estimated to be 7.4% when three stool samples were examined for all patients. Our study showed that repeated stool examinations increase the sensitivity of detection of S. stercoralis infection.     

Fluctuations of larval excretion in Strongyloides stercoralis infection.

Follow-up stool examinations were carried out on two groups of the subjects who were screened negative (group 1) or positive (group 2) for Strongyloides stercoralis by the agar plate culture. This technique could detect S. stercoralis larvae in 87.5-96.4% of the subjects in group 2 and 0-5.9% of the subjects in group 1 on various days of the eight-week and four-week follow-up periods, respectively. The detection rate on each day of examination was not statistically different from that on the first day in both groups. Quantitative measurement of S. stercoralis larvae excreted in the feces of the subjects in group 2 by the standard direct smear method of Beaver and others revealed slight to marked fluctuations of the larval output in individual subjects. From the results of both stool examination methods, it could be implied that 52% of S. stercoralis-infected individuals had low-level infection.     

Diagnostic Accuracy of Kato–Katz,FLOTAC, Baermann,and PCR Methods for the Detection of Light-Intensity Hookworm and Strongyloides stercoralis Infections in Tanzania

Sensitive diagnostic tools are crucial for an accurate assessment of helminth infections in low-endemicity areas. We examined stool samples from Tanzanian individuals and compared the diagnostic accuracy of a real-time polymerase chain reaction (PCR) with the FLOTAC technique and the Kato–Katz method for hookworm and the Baermann method for Strongyloides stercoralis detection. Only FLOTAC had a higher sensitivity than the Kato–Katz method for hookworm diagnosis; the sensitivities of PCR and the Kato–Katz method were equal. PCR had a very low sensitivity for S. stercoralis detection. The cycle threshold values of the PCR were negatively correlated with the logarithm of hookworm egg and S. stercoralis larvae counts. The median larvae count was significantly lower in PCR false negatives than true positives. All methods failed to detect very low-intensity infections. New diagnostic approaches are needed for monitoring of progressing helminth control programs, confirmation of elimination, or surveillance of disease recrudescence.     

The potential usefulness of the modified Kato thick smear technique in the detection of intestinal sarcocystosis during field surveys

A total of 479 stool specimens were collected from rural communities of Ubon Ratchathani Province, Thailand and examined by two techniques: the modified Kato thick smear and the direct smear. The prevalence of Opisthorchis viverrini (14.8%), hookworm (10.2%), Sarcocystis spp (4.6%), Taenia spp (2.9%), Strongyloides stercoralis (2.1%), Giardia lamblia (1.2%), Echinostoma spp (0.6%), Ascaris lumbricoides (0.4%), Entamoeba histolytica (0.2%), Chilomastix mesnili (0.2%) and Endolimax nana (0.2%) were determined. The morphology of the Sarcocystis spp sporocysts examined by both procedures looked similar and was found to be easily recognizable. Among these specimens, 22 cases (4.6%) were positive for Sarcocystis infection detected by the modified Kato technique, whereas only one case (0.2%) was detected by both techniques. These differences were found to be statistically significant (p < 0.05), indicating that the modified Kato technique was decidedly more sensitive than the direct smear procedure in identifying Sarcocystis infection. An epidemiological survey was conducted in Khon Kaen Province involving 1124 stool samples using the modified Kato technique. The greatest frequency was Opisthorchis viverrini at 32.0% while the second highest was Sarcocystis spp at 8.0%. The prevalences of hookworm, Echinostoma spp, Taenia spp, Trichuris trichiura and Enterobius vermicularis were 2.7, 2.1, 1.0, 0.2 and 0.2%, respectively. Other than opisthorchiasis, northeastern Thailand may be an endemic area for sarcocystosis. This is the first report of the applicability and potential usefulness of the Kato thick smear technique for the diagnosis of Sarcocystis infection in a field survey.     

Strongyloidosis. Part VIII. Parasitological diagnosis

The effectiveness and safety of the methods of detecting Strongyloides stercoralis, by passing larvae from the faeces to water, in duodenal fluid (duodenal intubation, Enterotest), in sputum and other body fluids, have been estimated. The author recommend Baermann technique for detecting S. stercoralis in individual examinations and Dancescu technique in mass field examinations. The detection of S. stercoralis larvae by the two methods ought to be checked by Fülleborn agar Petri dish technique in order to identify parasite to the species level.     

Intestinal parasites in school-aged children in villages bordering Tonle Sap Lake, Cambodia

The objective of this study was to study Schistosoma mekongi and other intestinal parasitic infections, and intestinal symptoms and related complaints among school-age children and adolescents living around Tonle Sap Lake. Villages were selected where there were potential signs of schistosomiasis (hepatomegaly), and where subjects complained of intestinal symptoms. Stool samples were collected from 1,616 children and were examined by Kato-Katz, SAF concentration, and Baermann technique; short clinical examinations were also performed. No S. mekongi infection was detected, although a high level of intense human water contacts was reported. Helminth infection such as Ascaris lumbricoides (27.7%) and hookworms (29.7%) were common. Trichuris trichiura 4.4%), Hymenolepis nana (6.2%), Giardia lamblia (4.2%), and Entamoeba spp (14.4%) were also recorded. Strongyloides stercoralis was frequently diagnosed (20.2%). It was concluded that it is unlikely that S. mekongi is transmitted in Tonle Sap Lake. However, other intestinal parasitic infections are widespread. In particular, S. stercoralis should be considered an important etiologic agent in children and adolescents with abdominal complaints.