Enhanced classification of Chagas serologic results and epidemiologic characteristics of seropositive donors at three large blood centers in Brazil

BACKGROUND: A major problem in Chagas disease donor screening is the high frequency of samples with inconclusive results. The objective of this study was to describe patterns of serologic results among donors to the three Brazilian REDS‐II blood centers and correlate with epidemiologic characteristics. STUDY DESIGN AND METHODS: The centers screened donor samples with one Trypanosoma cruzi lysate enzyme immunoassay (EIA). EIA‐reactive samples were tested with a second lysate EIA, a recombinant‐antigen based EIA, and an immunfluorescence assay. Based on the serologic results, samples were classified as confirmed positive (CP), probable positive (PP), possible other parasitic infection (POPI), and false positive (FP). RESULTS: In 2007 to 2008, a total of 877 of 615,433 donations were discarded due to Chagas assay reactivity. The prevalences (95% confidence intervals [CIs]) among first‐time donors for CP, PP, POPI, and FP patterns were 114 (99‐129), 26 (19‐34), 10 (5‐14), and 96 (82‐110) per 100,000 donations, respectively. CP and PP had similar patterns of prevalence when analyzed by age, sex, education, and location, suggesting that PP cases represent true T. cruzi infections; in contrast the demographics of donors with POPI were distinct and likely unrelated to Chagas disease. No CP cases were detected among 218,514 repeat donors followed for a total of 718,187 person‐years. CONCLUSION: We have proposed a classification algorithm that may have practical importance for donor counseling and epidemiologic analyses of T. cruzi–seroreactive donors. The absence of incident T. cruzi infections is reassuring with respect to risk of window phase infections within Brazil and travel‐related infections in nonendemic countries such as the United States.     

Epidemiologic and laboratory findings from 3 years of testing United States blood donors for Trypanosoma cruzi

BACKGROUND: At most blood centers in the United States routine testing of donations for Trypanosoma cruzi using an enzyme‐linked immunosorbent assay (ELISA) is followed by supplemental testing by radioimmunoprecipitation assay (RIPA). The objective of this study was to report the results of routine testing and risk factor data from allogeneic blood donors. STUDY DESIGN AND METHODS: T. cruzi testing data from January 2007 through December 2009 were analyzed, and risk factor interviews and follow‐up studies were conducted on seroreactive donors. Prevalences of confirmed infection and risk factors associated with infection were assessed using logistic and multivariable logistic regression. RESULTS: Of 2,940,491 allogeneic donations from 1,183,076 donors, 305 (0.01% per donation tested and 0.026% per blood donor) were repeat reactive (RR) and 89 of those were confirmed positive by RIPA, yielding an overall seroprevalence of 1 per 33,039 donations and 1 per 13,292 donors. Country of birth and US blood center location differences in the seroprevalence of T. cruzi were evident. The odds of confirmed infection were highest if the donor reported having been bitten by the reduviid (kissing) bug (odds ratio [OR], 76.1; 95% confidence interval [CI], 11.1‐3173) followed by having lived in a rural area of Latin America (OR, 38.6; 95% CI, 15.1‐102.5). In multivariable analyses, having spent 3 months or more in Mexico or Central and/or South America was associated with the highest odds of RIPA‐confirmed infection (OR, 8.5; 95% CI, 2.7‐26.5). Polymerase chain reaction (PCR) testing of ELISA RR donors exhibited low sensitivity (1/22 [4%] RIPA‐confirmed donors was PCR positive). CONCLUSION: Risk factors for confirmed infection in US blood donors are consistent with the known epidemiology of Chagas disease. Blood donors or transfusions do not substantially contribute to the burden of T. cruzi infection in the United States.     

Trypanosoma cruzi: seroprevalence detected in the blood bank of the Instituto Nacional de Pediatría, Mexico City, in the period 2004 through 2009

BACKGROUND: The second most common mode of Trypanosoma cruzi or Chagas disease transmission is via therapeutic blood transfusion. In Mexico, control of T. cruzi is still in its initial phase; in fact, there are only 14 studies published covering 10 states on T. cruzi seroprevalence in donated blood in Mexico. Here we present the results of 5 years of trypanosomiasis screening in the blood bank of the Instituto Nacional de Pediatría. STUDY DESIGN AND METHODS: Samples from all blood donated in the period from 2004 to 2009 were analyzed. We screened for T. cruzi using an enzyme‐linked immunosorbent assay technique. Seropositive samples were then processed using the polymerase chain reaction (PCR) to detect a nuclear gene segment. RESULTS: A total of 37,333 samples were analyzed and a 0.17% (64 samples) T. cruzi seroprevalence was found. Donors were mostly from Mexico State and Mexico City, which is considered nonendemic for T. cruzi area. Of 64 seropositive samples, only two tested positive by PCR (3.12%), which amplified a 189‐bp product from nuclear gene from the parasite. CONCLUSION: Although the seroprevalence of T. cruzi infection was low, this surveillance program prevented the infection of more than 100 children because each unit of blood provides 2.6 to 3.5 blood products. The majority of the donors were from Mexico State and Mexico City, which is a nonendemic area. The serodetection of T. cruzi in this region is evidence that is necessary to increase our understanding of its distribution in the Mexico City and surrounding places.     

Prevalence, incidence, and residual risk of human immunodeficiency virus among community and replacement first-time blood donors in São Paulo, Brazil

BACKGROUND: Concerted efforts have been directed toward recruitment of community rather than replacement donors in Brazil. Time trends and demographic correlates of human immunodeficiency (HIV) prevalence and incidence among first‐time (FT) donors in Brazil were examined by donation type. HIV residual risk from FT‐donor transfusions, and projected yield of p24 antigen and nucleic acid test (NAT) screening were estimated. STUDY DESIGN AND METHODS: HIV prevalence data and seroreactive specimens were obtained at Fundação Pró‐Sangue/Hemocentro‐de‐São Paulo from 1995 to 2001. To estimate incidence, confirmed‐positive samples from July 1998 through December 2001 were tested with a less‐sensitive (detuned) enzyme immunoassay to detect recent seroconversions. Incidence data were used to estimate residual risk and p24 and NAT yield based on published window periods (WPs). RESULTS: HIV prevalence was 22 percent higher among the FT community donors than replacement donors (19.6 vs. 16.1 per 10,000; p < 0.01) and 48 percent higher among men than women (19.1 vs. 12.9; p < 0.01). In the multivariable logistic regression, both variables remained significant predictors of HIV prevalence. HIV prevalence decreased from 20.4 (1995) to 13.1 per 10,000 FT donations (2001). HIV incidence was 2.7 per 10,000 person‐years. The estimated rate of infected antibody‐negative donations was 14.9 per 1,000,000 units (95% confidence interval, 9.8‐20.0). It was estimated that addition of p24 antigen, minipool NAT, and individual‐donation NAT assays would detect 3.9 (2.0‐5.8), 8.3 (5.3‐11.3), and 10.8 (7.1‐14.5) WP units per 1,000,000 FT donations, respectively. CONCLUSION: HIV incidence and residual transfusion risk estimates are approximately 10 times higher in Brazil FT donors compared to US and European FT donors. Community FT donors had higher HIV prevalence than replacement FT donors. The yield of p24 antigen or RNA screening will be low in Brazilian donors, but substantially higher than in US donors.     

无偿献血者乙肝表面抗原ELISA试剂筛查S/CO值与HBsAg阳性的相关性研究

目的了解献血者乙肝病毒表面抗原(HBsAg)初筛(试剂)反应性结果S/CO值与真阳性的相关性,为制定合理的HBsAg初筛反应性献血者归队策略提供依据。方法采用3种HBsAg酶联免疫吸附试验(ELISA)试剂(以国产试剂1、国产试剂2、进口试剂代称)和1种国产核酸检测(NAT)试剂对2017年7月—2017年9月在长春市献血的9 951(人)份献血者血标本做初筛试验,凡是反应性[包括所有试剂(试验)反应性、单试剂反应性和灰区反应性(0.8≤S/CO﹤1.0)]血清标本再以中和试验(ELISA法)确证。使用SPSS 16.0统计学软件绘制HBsAg S/CO值与确证结果的接受者操作特性曲线(ROC),分析各S/CO值区间的阳性预测值,寻找灵敏度和特异性相适的S/CO值临界点。结果 1)献血者HBsAg初筛反应性率0.58%(58/9951),中和试验确证HBsAg阳性者比例20.69%(12/58)、阴性者比例79.31%(46/58)例;ELISA国产试剂1、2及进口试剂初筛与中和试验的阴性符合率均为100%,阳性符合率分别为57.14%(12/21)、66.67%(12/18)及27....     

Results of lookback for Chagas disease since the inception of donor screening at New York Blood Center

BACKGROUND: Chagas disease is a parasitic infection by Trypanosoma cruzi, typically transmitted via infected triatomine bug fecal contamination of bite sites. Other routes of infection include congenital, oral, organ transplantation, and blood product transmission. STUDY DESIGN AND METHODS: From 2007 until 2011, New York Blood Center screened donations for the presence of T. cruzi antibodies using a Food and Drug Administration–approved test. Confirmatory testing was performed and recipients of units donated by confirmed‐positive donors were investigated via lookback. RESULTS: A total of 204 donors were T. cruzi antibody positive representing 0.019% of all donors during this time period (1,066,516 unique donors screened). Of the enzyme‐linked immunosorbent assay–reactive donors, 77 were confirmed positive by radioimmunoprecipitation assay (0.007%). At least 154 units from 29 of the confirmed‐positive donors had been transfused to 141 recipients. At the time of lookback, 48 of the 141 recipients were alive and seven underwent T. cruzi screening. Two recipients were found to be immunofluorescence assay (IFA) positive. Both IFA‐positive recipients received a leukoreduced apheresis platelet unit (two separate donations) from the same confirmed positive donor, a 72‐year‐old immigrant from Argentina. CONCLUSIONS: Lookback analysis was able to identify the first two cases of probable transfusion‐transmitted T. cruzi infection since implementation of the national screening program, which increases the total number of reported cases in the United States to 8.     

Lookback investigations of Babesia microti-seropositive blood donors: seven-year experience in a Babesia-endemic area

BACKGROUND: Human babesiosis in the United States is primarily attributable to infection with the intraerythrocytic protozoan parasite, Babesia microti. Transfusion‐transmitted Babesia (TTB) is a mounting blood safety concern; approximately 100 US cases of TTB have been reported since 1980. In response, market withdrawal (MW) and/or lookback (LB) has been advocated for cellular components derived from Babesia‐positive blood donors. STUDY DESIGN AND METHODS: Immunofluorescence assay (IFA) and selective polymerase chain reaction (PCR) testing of Connecticut donors was conducted from 1999 through 2005. MW/LB was initiated following established procedures on cellular components derived from IFA and/or PCR‐positive donors. Recipients of these associated components were offered IFA and PCR testing for B. microti. RESULTS: A total of 208 seropositive donors were identified, with 474 donations and 656 cellular components subject to MW/LB. Sixty‐three recipients were tested for B. microti; eight (12.7%) were IFA and/or PCR positive. A significantly higher proportion of B. microti–positive recipients were identified by LB in 1999 to 2000 (5 of 15, 33.3%) than after implementation of seropositive donor deferral in 2001 (3 of 48, 6.3%). Significant differences in positive LBs were also found when comparing index (50% positive) to previous donations (7.3% positive), and when comparing demonstrably parasitemic to nonparasitemic donors, 33.3 and 2.9%, respectively. CONCLUSIONS: Recipients of components from B. microti–positive donors were infected via transfusion, with index donations from parasitemic donors posing the greatest transmission risk. This report of B. microti transmission detected through LB, coupled with ongoing TTB cases, indicates that interventions are needed to reduce transmission of B. microti to US blood recipients.     

Transmission of HCV infection by RIBA indeterminate and positive blood units

A retrospective study was carried out on the recipients of 73 units of blood from 53 donors found reactive for anti-HCV. The donors were screened with anti-HCV enzyme-linked immunosorbent assay (ELISA C-100) and reactivity was confirmed with the first generation recombinant immunoblot assay (RIBA I). Fifty-two patients were recipients of blood from donors reacting as RIBA I 'indeterminate' and 21 of blood from RIBA I 'positive' donors. Only three recipients (5.8%) from 'indeterminate' donors were anti-HCV positive indicating that such donors are very seldom infectious. Eleven (52.4%) recipients from 'positive' donors had antibodies to HCV, indicating that not all RIBA-positive donors are necessarily infectious. Pretransfusion samples of the seropositive recipients were unavailable. All samples were analyzed with the first generation ELISA and with either the second-generation ELISA or RIBA (RIBA II) in order to evaluate test sensitivity. RIBA II was more sensitive than RIB I. One RIBA I indeterminate donor was positive by RIBA II. His recipient had antibodies to HCV. Twelve RIBA I indeterminate and three RIBA I positive donors were negative by RIBA II. All their recipients were anti-HCV negative. The second-generation ELISA was also shown to be more sensitive than ELISA C-100. The second-generation ELISA detected six confirmed anti-HCV positive recipients who were negative by ELISA C-100.     

芜湖地区无偿献血者HIV筛查策略及确认结果分析

目的分析芜湖地区无偿献血者中HIV感染情况,为完善献血招募策略和临床安全用血提供有效数据。方法选取2017年1月~2020年9月芜湖地区全部无偿献血者中HIV筛查反应性标本,送检至市疾控中心进行确认试验。利用受试者工作特征曲线(ROC曲线)比较酶免试剂的准确性;通过ELISA检测最适临界值分析血清学灰区设置;比较确认阳性、阴性和不确定标本的初筛S/CO值,使用SPSS 22.0软件分析差异显著性。结果送检75例HIV初筛反应性标本:确认阳性17例,17例不确定,41例阴性。4代抗-HIV ELISA试剂的曲线下面积(AUC)大于3代试剂,在准确性上4代试剂更优于3代试剂;17例确认阳性标本均是双试剂反应性高S/CO值,其初筛S/CO值显著高于确认阴性和不确定标本初筛值(P<0.05),确认阴性和不确定结果的S/CO值没有统计学差异(P>0.05)。结论芜湖地区无偿献血者中HIV感染率处于全国中等水平;血清学检测的灰区设置意义不大;应通过规范的献血前干预、灵敏的核酸检测技术和共享区域数据平台等措施进一步保障血液安全。     

The United States Trypanosoma cruzi Infection Study: evidence for vector-borne transmission of the parasite that causes Chagas disease among United States blood donors

BACKGROUND: Screening US blood donors for Trypanosoma cruzi infection is identifying autochthonous, chronic infections. Two donors in Mississippi were identified through screening and investigated as probable domestically acquired vector‐borne infections, and the US T. cruzi Infection Study was conducted to evaluate the burden of and describe putative risk factors for vector‐borne infection in the United States. STUDY DESIGN AND METHODS: Blood donors who tested enzyme‐linked immunosorbent assay repeat reactive and positive by radioimmunoprecipitation assay, and whose mode of infection could not be identified, were evaluated with a questionnaire to identify possible sources of infection and by additional serologic and hemoculture testing for T. cruzi infection. RESULTS: Of 54 eligible donors, 37 (69%) enrolled in the study. Fifteen (41%) enrollees had four or more positive serologic tests and were considered positive for T. cruzi infection; one was hemoculture positive. Of the 15, three (20%) donors had visited a rural area of an endemic country, although none had stayed for 2 or more weeks. All had lived in a state with documented T. cruzi vector(s) or infected mammalian reservoir(s), 13 (87%) reported outdoor leisure or work activities, and 11 (73%) reported seeing wild reservoir animals on their property. CONCLUSION: This report adds 16 cases, including one from the Mississippi investigation, of chronic T. cruzi infection presumably acquired via vector‐borne transmission in the United States to the previously reported seven cases. The estimated prevalence of autochthonous infections based on this study is 1 in 354,000 donors. Determining US foci of vector‐borne transmission is needed to better assess risk for infection.     

Seroprevalence of Trypanosoma cruzi infection in at-risk blood donors in Catalonia (Spain)

BACKGROUND: The increasing arrival of Latin Americans to Europe and, particularly, to Spain has led to the appearance of new pathologies, such as Chagas disease, a zoonotic infection endemic to rural areas of Central and South America. In the absence of the triatomid vector, one of the main modes of transmission of Chagas disease in nonendemic regions is through blood transfusion. STUDY DESIGN AND METHODS: The Catalonian Blood Bank has implemented a screening program for Chagas disease in at‐risk blood donors and has performed a study to determine the seroprevalence of Trypanosoma cruzi infection in the donor population. The two commercial tests used in all samples were the ID‐PaGIA Chagas antibody test (DiaMed) and the bioelisa Chagas assay (Biokit). RESULTS: Overall seroprevalence was 0.62 percent, with 11 donors confirmed positive among the 1770 at‐risk donors studied; the highest rate (10.2%) was in Bolivian donors. Interestingly, 1 of the 11 positive donors was a Spaniard who had resided various years in a Chagas disease endemic area. Furthermore, 1 of the positive donors presented detectable parasitemia. CONCLUSION: The results of this study emphasize the need for T. cruzi screening in at‐risk blood donors in nonendemic countries. An important finding is the relevance of including in the at‐risk category persons who have resided in, but were not necessarily born in, an endemic region. If T. cruzi screening is not routinely performed in all donations, it remains highly dependent on proper identification of at‐risk donors during the predonation interview.     

The usefulness of multiplex PCR for the identification of bacteria in joint infection

Background: The diagnosis of septic arthritis (SA) relies on synovial analysis and conventional culture. But, these methods lack of sensitivity and culture is time consuming to establish a definite diagnosis. This study evaluated a new multiplex PCR assay which entailed screening PCR for Gram typing and identification PCR for species identification using two primer mixes. Methods: A total of 80 synovial fluid samples from patients with suspected SA were collected. Culture, multiplex PCR, and 16S rRNA gene PCR were performed. Results: The analytical sensitivity of multiplex PCR assay was 10¹ CFU/ml for each type of bacteria. There was no cross‐reactivity with common bacterial pathogens. Bacteria were detected in 20, 25, and 26 of 80 samples for culture, multiplex PCR, and 16S rRNA gene PCR, respectively. Nineteen (95%) of 20 culture‐positivesamples and 6 (10%) of 60 culture‐negative samples were positive for the multiplex PCR. Five of six samples which were positive only from multiplex PCR were also positive in 16S rRNA gene PCR. The multiplex PCR showed 2 false‐negative in 27 true‐positive samples but no false‐positive. The sensitivity and specificity of the multiplex PCR were 92.6 and 100%, and the agreement with culture and 16S rRNA gene PCR were 91.3 and 96.3%, respectively. The time to detection for multiplex PCR was a maximum of 6 hr. Conclusion: This multiplex PCR assay offers high sensitivity and improved detection speed relative to culture. The appropriate combination of this new multiplex PCR assay with culture may contribute to the accurate and rapid diagnosis of SA. J. Clin. Lab. Anal. 24:175–181, 2010. © 2010 Wiley‐Liss, Inc.     

HBsAg酶联免疫吸附试验灰区设置研究

目的评价与验证该实验室乙型肝炎表面抗原(HBsAg)试验设置0.9倍临界值(CO值)的合理性。方法参照美国临床和实验室标准协会(CLSI)发布的EP12-A2指南,通过试验确定HBsAg试验C5~C95区间即灰区。对HBsAg灰区标本进行抗体确认试验。绘制受试者工作特征曲线(ROC曲线)确定HBsAg试验最佳CO值。通过实验室既往数据,分析乙型肝炎病毒DNA(HBV-DNA)单阳性标本酶联免疫吸附试验(ELISA)结果分布(S/CO值)与灰区的关系。结果 (C50±20%)水平检测结果阴性数和阳性数均大于或等于95%,(C50-20%)~(C50+20%)水平范围包含C5~C95区间,灰区范围应在0.712~1.103倍CO值区间内。对44例HBsAg灰区标本(S/CO值0.900~0.990)进行中和试验,结果均为无反应性。绘制HBsAg的ROC曲线,曲线下面积(AUC)为0.981,最适CO值为0.063(现用CO值在0.055~0.060)。2010年11月2日至2013年12月31日检测标本研究886 291例患者,HBsAg阳性标本包括135例灰区标本,其中7例核酸检测法(NAT)检测结果均为反应性;共检出HBV-DNA单阳性标本421例,其HBsAg检测结果(S/CO值)分布区间为0.200~0.400,与阴性标本分布区间重叠、距0.9倍CO值较远。结论该实验室现阶段HBsAg试验设置0.900的CO灰区过于严苛,试验结果支持取消灰区设置。报道所提供的4种灰区评价方法为其他实验室在设置ELISA试验灰区方面提供了1种思路。     

一种国产HBsAg确认试剂的临床应用评价

目的 评价一种国产HBsAg确认试剂的临床应用价值.方法 对543份经HBsAgELISA初筛吸光度值/临界值(S/CO)10.7的血清标本,用国产HBsAg确认试剂盒进行确认,在双份待确定标本中分别加入特异性抗-HBs试剂和对照试剂,保温后按常规HBsAg ELISA法测定吸光压(A)值,按公式求得加抗-HBs孔的抑制率,如抑制率≥50%即表示该标本被确认为HBsAg阳性.对HBsAg弱阳性的标本进行"延长确认试验",即延长酶反应时间,以提高检测的灵敏度.随机挑选39份弱阳性标本用美国雅培公司Murex HBsAg确认试验进行比对.结果 对543份标本进行确认试验,其中504份初筛HBsAg阳性的标本中,被确认为阴性的有89份(17.7%),按初筛不同S/CO值分区的阴性份数/检测份数分别为:S/CO≤5.0有87/143(60.8%),5.0相似文献   

Recognition of cytomegalovirus clinical isolate antigens by sera from cytomegalovirus-negative blood donors

BACKGROUND: The most common way to prevent transmission of CMV by blood transfusion is to use blood products from seronegative donors. Screening of blood donors for CMV infection is usually based on detection of antigens obtained from the CMV laboratory strain AD 169. Recent evidence suggests that approximately up to 20 percent of CMV-negative blood donors may in fact be CMV-DNA positive by PCR analyses. STUDY DESIGN AND METHODS: In this study, sera from CMV-seronegative, CMV-seropositive, and CMV-DNA-positive/seronegative individuals, and from patients with acute and convalescent CMV infection for detection of CMV antibodies were analyzed. CMV antigens prepared from cells infected with CMV clinical isolates or the CMV laboratory strain AD 169 in ELISA and Western blot assays were used. RESULTS: All CMV-positive sera from blood donors were seropositive for the CMV antigens prepared from AD 169 (A2) or from a CMV clinical isolate (C6). Interestingly, whereas all CMV-negative blood donors were negative in tests for the CMV antigen A2, 36 percent were CMV seropositive using the CMV antigen C6 in ELISA. CONCLUSION: The data suggest that a substantial number of CMV-seronegative/CMV-DNA-positive serum samples contain antibodies that recognize CMV clinical isolate antigens.     

太原市无偿献血者抗-HIV结果确认和带型分析

目的分析研究太原市无偿献血者人类免疫缺陷病毒(HIV)抗体(抗-HIV)阳性标本的确认结果和带型。方法采用蛋白印迹(WB)对185例初筛阳性献血者标本进行确认试验,采用SPSS13.0分析试验结果和带型。结果确认阴性128例,不确定15例、阳性42例。确认阳性标本中,gp120、gp160、p24带型阳性率为100.00%,p31、p51和p66阳性率均大于90.00%。不确定标本中,p24阳性率最高,有12例,占80.00%;其次为gp160,有3例,占20.00%。随着S/CO值增大,带型出现率逐渐增高,最高为S/CO值6.00组(χ~2=35.16,P=0.009)。结论 HIV筛查试验存在假阳性。确认阳性标本多为病毒感染期。初筛阳性标本必须进行追踪确认试验,确认其是否感染。     

广州献血人群抗-HCV ELISA检测S/CO值与确证试验结果的相关性

目的研究广州献血人群抗-HCV ELISA检测试验S/CO值与确证试验(NAT和RIBA)结果的相关性。方法采用进口(Abbot或Ortho)和国产(科华)抗-HCV ELISA试剂对2009年2月～2012年4月广州血液中心采集的无偿献血者血浆标本作抗-HCV检测,从中随机收集664份双试剂呈反应性的血浆标本进一步作确证试验;使用ROC曲线分析3种ELISA试剂的S/CO值与确证试验结果的相关性。结果 ROC曲线分析显示3种ELISA试剂检测的S/CO值与确证试验结果具有相关性:以Youden指数最大时的S/CO值为最佳阈值,Abbot、Ortho及科华试剂分别为3.234、4.460和6.976,均可预测>95%的确证试验阳性结果。结论不同试剂具有各自的最佳S/CO阈值,可以通过S/CO值预测HCV感染确证试验的阳性结果。     

Comparison of two anti-hepatitis C virus enzyme-linked immunosorbent assays

BACKGROUND: Third-generation anti-hepatitis C virus (HCV) enzyme-linked immunosorbent assays (ELISA) are now implemented in most laboratories in Europe, but have not yet been fully implemented in the United States. STUDY DESIGN AND METHODS: Two ELISAs (Ortho 3.0 and Ortho 2.0, Ortho Diagnostics, Raritan, NJ) were compared by tests on various serum panels: A) blood donor samples (n = 530) that tested positive in first- or second-generation anti-HCV ELISA; B) samples from persons with chronic non-A, non-B hepatitis (n = 185); C) samples from multiply transfused patients (n = 79); D) samples from patients on hemodialysis (n = 473); and E) samples from Dutch random blood donors (n = 2153). RESULTS: In panels A, B, and C, 247 (100%) of 247 polymerase chain reaction (PCR)-positive and 278 (100%) of 278 second-generation recombinant immunoblot assay (RIBA-2)-positive specimens were detected by Ortho 2.0 and 3.0 (sensitivity, 100%). In the sera of panel D, used to represent a group of patients with a high risk for HCV, no additional positives were found by Ortho 3.0. In panel E, of 2153 blood donor samples, 2 (0.1%) were positive in Ortho 2.0 and 8 (0.4%) in Ortho 3.0. Two samples that were positive in both Ortho 2.0 and 3.0 were also positive in RIBA-2; one was positive on PCR. From the 6 remaining Ortho 3.0-positive (Ortho 2.0-negative) samples, 1 was positive in RIBA-2 (isolated anti-c100) and 3 were positive in third- generation RIBA (1/3 isolated anti-c100, 2/3 isolated NS5). All 6 samples were PCR negative. In first-time donors, no difference in specificity was found. CONCLUSION: The sensitivity and specificity of the Ortho 3.0 ELISA are comparable to those of the Ortho 2.0 ELISA.     

北京地区献血人群人类巨细胞病毒及人类T淋巴细胞白血病病毒感染情况调查

目的 了解北京地区人类巨细胞病毒(HCMV)及人类T淋巴细胞白血病病毒(HTLV)在无偿献血人群中的感染情况。方法 北京地区2 010例无偿献血者血液标本采用ELISA方法筛查HCMV-IgG,HCMV-IgM,HTLV-Ⅰ/Ⅱ抗体。初检阳性标本进行双孔复检,两次检测结果均为阳性标本判定为ELISA结果阳性,HTLV阳性样品经巢式PCR检测核酸进行确认。结果 北京地区2 010例无偿献血者中HCMV-IgM和HCMV-IgG阳性率分别为2.19%和92.59%,ELISA法初筛抗-HTLV阳性1例,巢式PCR确认结果阴性。结果 通过χ²检验统计学分析显示,无偿献血者HCMV-IgG阳性率男性低于女性(χ²=5.88,P＜0.05),18～25岁年龄段的献血者HCMV-IgG和HCMV-IgM阳性率低于其他年龄段(χ²=16.51,21.52; 均P＜0.05),大学生HCMV-IgG阳性率低于其他职业献血者(χ²=14.20,P＜0.05),而献血者教育程度与HCMV-IgG和HCMV-IgM阳性率无关(P＞0.05)。结论在该次调查中,北京地区2 010例无偿献血者中未发现感染HTLV的病例,而HCMV感染率与性别、年龄、职业相关,与教育程度无关。