液态芯片的高敏感性检测HIV-1 RNA

目的建立高敏感的液态芯片检测血液HIV-1 RNA的方法。方法抽提NASBA（nucleic acid sequence-based amplification）确定HIV-1 RNA载量的患者血浆RNA，对HIV-1引物进行生物素标记，行一步法RT-PCR扩增靶HIV-1 gag区片段。PCR产物与两个交联HIV-1特异探针的微球杂交，同时对于HIV-1病毒载量在100-790拷贝/ml样本进行荧光定量PCR检测。结果对NASBA确定阳性的上海108例（载量170-3 300 000）、COBAS定量的北京86例阳性（载量477-2 040 000）以及5例NIH的HIV标准品（〈100；273；1 610；11 300；33 800）的结果进行液态芯片多区段检测HIV-1 RNA，总阳性率为96.98%（193/199），液态芯片检测的敏感性与NASBA、COBAS方法相当（P〉0.05），对于HIV-1 RNA载量在180-790拷贝/ml的13个样本的荧光定量PCR未检测到信号，液态芯片检测结果为阳性。结论多区段液态芯片法检测HIV-1 RNA灵敏度高、特异性强、重复性好，降低漏检率，而且具有操作简便、快速、低成本的特点，将液态芯片技术应用于血液筛查将有助于提高HIV-1阳性血液的检出率和输血的安全性。     

我国HIV-1 B’亚型感染长期存活者病毒分离及体外复制的研究

目的从HIV-1B’亚型感染的长期存活者分离HIV-1病毒,观察HIV-1病毒分离与CD4淋巴细胞水平和病毒载量的相关性。方法采用外周血单核细胞共培养法,从感染者外周血分离HIV-1毒株,测定其复制动力学,并比较HIV分离率与CD4细胞计数和病毒载量的关系。结果从190例HIV感染者中分离到101株HIV-1病毒,平均病毒分离率为53%;载量为<103、103～104、104～105和>105拷贝/ml时,病毒分离率分别为3.7%、36%、68%和73%;CD4细胞计数为<200、200～500和≥500个/μl时,病毒分离率分别为66%、59%和28%。结论HIV病毒培养阳性率与CD4细胞计数呈负相关,与病毒载量呈正相关;HIV体外复制力与病毒载量呈正相关关系。     

我国 HIV-1 B''''亚型感染长期存活者病毒分离及体外复制的研究

目的从HIV-1B’亚型感染的长期存活者分离HIV-1病毒,观察HIV-1病毒分离与CD4淋巴细胞水平和病毒载量的相关性。方法采用外周血单核细胞共培养法,从感染者外周血分离HIV-1毒株,测定其复制动力学,并比较HIV分离率与CD4细胞计数和病毒载量的关系。结果从190例HIV感染者中分离到101株HIV-1病毒,平均病毒分离率为53%;载量为<103、103～104、104～105和>105拷贝/ml时,病毒分离率分别为3.7%、36%、68%和73%;CD4细胞计数为<200、200～500和≥500个/μl时,病毒分离率分别为66%、59%和28%。结论HIV病毒培养阳性率与CD4细胞计数呈负相关,与病毒载量呈正相关;HIV体外复制力与病毒载量呈正相关关系。     

梅毒对HIV-1感染者病毒载量和CD4+T细胞计数的影响

目的:评估梅毒对HIV-1感染者血浆HIV-1病毒载量,CD4 T细胞计数的影响.方法:于1年前对HIV-1感染者进行梅毒ELISA和RPR检测,对RPR检测阳性者根据其CD4 T细胞计数和病毒载量进行配对,与1年后重新检测CD4 T细胞计数与病毒载量比较,用配对资料的t检验分析梅毒对HIV感染者CD4 T细胞与病毒载量的影响.结果:在271例HIV-1感染者中,共11例梅毒阳性者,占4.1%.本研究中包括HIV-1感染者20例,其中10例梅毒与HIV-1共感染者.在梅毒与HIV共感染者病例中,CD4 T细胞计数明显降低(99个细胞/ml),但病毒载量的变化没有显著差异.结论:梅毒显著地降低HIV-1感染者的CD4 T细胞数量,但病毒载量没有明显的变化.为了延缓HIV-1感染者进入AIDS阶段的时间,应加强对梅毒的治疗和采取相应的预防措施.     

广东省HIV/HCV共感染者及单纯HIV感染者HIV-1基因亚型分析

目的了解广东地区HIV/HCV共感染患者和单纯HIV感染患者的感染途径及HIV-1病毒基因亚型分布特征,为艾滋病的治疗与预防提供实验室数据。方法采用巢式RT-PCR对广东地区51例HIV/HCV共感染患者和48例单纯HIV感染患者HIV-1 ENV基因c2v3区域及GAG基因p17区域进行扩增,PCR产物测序后所获得序列进行HIV-1病毒基因亚型分析。结果 HIV/HCV共感染患者主要感染途径为静脉注射毒品,约占82%,其HIV-1有4种基因亚型,不同亚型以及比例分别为CRF01_AE(54.9%)、CRF07_BC(33.3%)、CRF08_BC(4%)和B’型(7.8%),CRF01_AE亚型为经静脉注射毒品感染的HIV/HCV共感染患者的主要HIV-1基因亚型,约占54.7%;单纯HIV感染患者主要感染途径为性,约占77%,其HIV-1有5种基因亚型,不同亚型及比例分别为CRF01_AE(77.1%)、CRF07_BC(10.4%)、CRF08_BC(6.2%)、B’型(4.2%)和B型(2.1%),CRF01_AE亚型为经性途径感染的单纯HIV感染患者的主要HIV-1基因亚型,约占78.4%。结论广东省HIV/HCV共感染患者和单纯HIV感染患者中流行的HIV-1病毒基因亚型呈现多样性,尽管HIV/HCV共感染患者的主要感染途径与单纯HIV感染患者的不同,但HIV-1病毒主要基因亚型相同。     

血浆IL-6、IL-2、IL-21在HIV-1感染病程进展的特征性分析

目的 研究3种血浆细胞因子白介素-6(interleukin 6,IL-6),白介素-2(interleukin 2,IL-2)和白介素-21(interleukin 21,IL-21)在人类免疫缺陷病毒1型(Human immunodeficiency virus type 1,HIV-1)感染者和正常人血浆表达水平及其在HIV-1感染病程进展中的相关性。方法 收集2017年1月至2019年9月未经抗病毒治疗(anti-retroviral therapy, ART)的HIV-1感染者27例(HIV组);ART后血浆病毒载量低于检测限,CD4>350cells/μl者22例(HIVⅠ组);ART后血浆病毒载量>1 000copies/ml, CD4<350cells/μl者31例(HIVⅡ组),另选30例健康体检者为对照组。采用酶联免疫吸附试验(enzyme linked immunosorbent assay, ELISA)检测3种细胞因子水平,流式细胞术检测CD4细胞数量,实时聚合酶链法测定血浆病毒载量。结果 HIV-1感染者血浆IL-6水平显著高于对照组,IL...     

HIV和HCV感染者重叠感染HGV对病毒复制的影响

目的 :了解人免疫缺陷病毒 (HIV)感染者和丙型肝炎病毒 (HCV)感染者重叠感染庚型肝炎病毒 (HGV)的情况 ,探讨重叠感染病毒在体内的相互作用机理。方法 :用定量 PCR测定 HIV和 HCV感染者血浆中病毒载量 ,同时用 RT- PCR检测这些患者 HGV的感染情况 ,并对部分 HGV阳性者进行序列测定。结果 :317例 HIV患者中检出 HGV阳性 12 3例 ,阳性率为 38.8% ;91例 HCV患者中 HGV阳性 19例 ,阳性率为 2 0 .9% ,统计学分析有显著差异。进一步研究显示 ,HIV和 HGV重叠感染中 HIV病毒载量明显低于单独 HIV感染者 [(1.8± 0 .6 )× 10copies/ ml vs(1.9± 1.1)× 10 2 copies/ ml];而 HCV和 HGV重叠感染者中 HCV的病毒载量与单独 HCV感染者比较没有显著差异 [(1.5± 0 .6 )× 10 4copies/ ml vs(5 .4± 1.8)× 10 4copies/ ml]。序例分析表明 ,与 HIV或 HCV重叠感染的 HGV来源于同一病毒株。结论 :HIV感染者有很高的 HGV重叠感染率 ,而且 HGV感染能明显抑制 HIV在体内的病毒复制。     

HIV-1感染者合并HBV、HCV感染情况分析

目的 分析人类免疫缺陷病毒（HIV）感染者合并乙型肝炎病毒(HBV)或/和丙型肝炎病毒(HCV）感染的情况。方法 对260例HIV感染者的HBV或/和HCV合并感染情况进行回顾性分析,对HIV单独感染者、HIV/HBV合并感染者、HIV/HCV合并感染者及HIV/HBV/HCV合并感染者的CD4+T细胞数、CD4+/CD8+细胞比值及HIV-RNA载量水平进行比较分析。结果 在260例HIV感染者中,60例为HIV/HCV合并感染（23.1%）,29例为HIV/HBV合并感染（11.2%）,8例为HIV /HBV/HCV合并感染（3.1%）;男性的HIV/HCV合并感染率显著高于女性 （P<0.01）; HIV-1/HBV和HIV-1/HCV合并感染者的CD4+/CD8+ 细胞比值均显著低于HIV单独感染者（P<0.05）;HIV-1/HCV合并感染者的CD4+细胞数显著低于HIV单独感染者（P<0.05）;三组合并感染者的HIV-RNA载量与HIV单独感染者之间差异不显著。结论 HIV/HCV合并感染率显著高于HIV/HBV合并感染率;HIV感染者合并HBV、HCV感染可能进一步加重HIV/AIDS患者的细胞免疫功能损伤,以HIV/HCV合并感染尤甚。     

HIV-1 B’亚型病毒感染者辅助蛋白Vpr特异性细胞免疫应答

目的探讨HIV-1 B’亚型病毒感染者针对辅助蛋白Vpr的细胞免疫(CTL)反应特征及其与病毒复制控制的关系。方法利用检测IFN-γ分泌的ELISPOT方法,以覆盖HIV-1 B亚型Vpr蛋白全长的重叠肽段作为刺激抗原检测143例未接受抗病毒治疗的HIV-1 B’亚型病毒感染者针对Vpr蛋白的特异性细胞免疫反应,并分析其与病毒载量的关系。结果有16.8%的感染者可以产生针对Vpr蛋白的特异性CTL反应;能识别至少一条Vpr多肽的感染者的病毒载量低于不能识别Vpr多肽的感染者的病毒载量,差别有统计学意义(P=0.0191);对VPR-B-3多肽的识别与低病毒载量紧密相关,该多肽可能包含与Vpr蛋白的生物学功能相关的关键氨基酸位点;Vpr蛋白区多肽在人群中的识别水平的差异与其序列变异程度有关。结论Vpr蛋白特异性的CTL反应与宿主对病毒复制的控制具有一定的相关性,对Vpr蛋白区所包含的CTL表位进行鉴定并探讨其在感染过程中的作用,可为HIV疫苗设计提供参考依据。     

Alu-LTR PCR方法检测HAART治疗系列各细胞亚群的整合型HIV-1 DNA

目的应用Alu-LTR PCR方法对高效抗反转录病毒治疗(highly active antiretroviral therapy,HAART)系列的CD4+T,CD8+T及B细胞进行检测,明确不同细胞亚群及HAART治疗的不同阶段是否存在整合的HIV-1 DNA。方法收集20例HIV-1感染患者HAART治疗过程中0、4、12周及10例健康对照的抗凝血标本,纯化CD4+T,CD8+T及B细胞并提取DNA,应用Alu-LTR PCR方法进行检测。结果 20例HIV-1感染者HAART治疗系列中CD4+T细胞及CD8+T细胞成功扩出目的片段,CD8+T细胞所扩条带亮度均低于CD4+T细胞,HAART治疗系列0、4、12周标本所扩条带亮度没有明显差异。B细胞及10例健康者均为阴性。结论 CD4+T及CD8+T细胞存在整合型HIV-1 DNA,HIV储藏库主要存在于CD4+T细胞内。B细胞内不存在整合型HIV-1 DNA。随着HAART治疗的进程,整合型HIV-1 DNA仍然存在,进一步证明HAART不能根除HIV储藏库。     

调节性CD4~+T细胞及非调节性CD4~+T细胞与HIV/AIDS患者疾病进展关系的研究

目的分析比较中国HIV感染者CD4+CD25+Foxp3+调节性T细胞(CD4+regulatory T cells,Treg)及非Treg细胞与疾病进展的关系,探讨Treg细胞在HIV感染过程中的作用。方法选取76例HIV/AIDS患者,根据其CD4+T细胞计数水平不同分为3组,A组CD4<200个/μL,B组CD4200～400个/μL,C组CD4>400个/μL。采用流式细胞仪胞内染色技术检测CD4+CD25+Foxp3+调节性T细胞的水平,并分析其与CD4计数及病毒载量的相关性。结果随着疾病的进展,Treg细胞百分比逐渐升高,各组间差异有统计学意义;Treg细胞及非Treg细胞的绝对计数均明显下降,且以非Treg细胞下降为主;Treg绝对计数与病毒载量呈负相关(P<0.05)。结论中国HIV感染者随着疾病进展,辅助性T细胞等非Treg细胞的数量下降,对机体免疫保护能力降低,而Treg细胞数量及功能的下降使其对机体的过度免疫活化的抑制作用减弱,病毒复制,加剧病情进展。     

Alu-LTR PCR检测整合型HIV-1实验方法的优化

目的对Alu-LTRPCR检测整合型HIV-1的实验方法进行优化。方法收集20例HIV-1感染患者及10例健康对照者的抗凝血标本,纯化CD4+T细胞并提取DNA,根据整合型HIV-1DNA的特点设计引物,首轮PCR5′端引物来自于人类保守的Alu序列,3′端引物来自于HIV-1LTRU5区序列,扩增片段包含了整合位点上游的人类基因组DNA序列和整合的HIV-1LTR的序列。第二轮引物针对HIV-1LTRU3区的序列。在首轮PCR基础上,PCR产物稀释后进行第二轮PCR。结果经过优化的Alu-LTRPCR,20例HIV病人全部检测到整合的HIV-1。结论经优化后,Alu-LTRPCR检测整合型HIV-1的实验方法的灵敏度明显提高。     

Prognostic Indicators for AIDS and Infectious Disease Death in HIV-Infected Injection Drug Users: Plasma Viral Load and CD4+ Cell Count

Context.— Plasma human immunodeficiency virus type 1 (HIV-1) viral load and CD4⁺ cell count are used to predict prognosis of persons infected with HIV. However, whether combining these markers improves prognostic accuracy and whether they predict prognosis for injection drug users (IDUs) and nonwhite persons infected with HIV has not been extensively investigated. Objective.— To evaluate plasma viral load and CD4⁺ cell count as prognostic indicators for the acquired immunodeficiency syndrome (AIDS) and infectious disease deaths. Design.— Cohort study initiated in 1988 and 1989 with follow-up for up to 7.9 years. Participants.— Injection drug users infected with HIV recruited from the community in Baltimore, Md. Main Outcome Measures.— Plasma HIV-1 RNA and CD4⁺ cell count measured at baseline compared with time to first clinical AIDS diagnosis and death due to an infectious disease. Results.— Of 522 subjects, 96% were African American, 80% were male, 96% injected drugs within the past 6 months, and the median age was 33 years. A total of 146 cases of AIDS and 119 infectious disease deaths were seen during a median follow-up period of 6.4 years. Time-fixed baseline levels of viral load and CD4⁺ cell count were independent predictors of progression to AIDS and infectious disease deaths, but in proportional hazards models, viral load had better predictive value than CD4⁺ cell count. Kaplan-Meier analysis of time to AIDS and to infectious disease deaths by viral load (<500, 500-9999, 10000-29999, 30000 copies/mL) at 3 levels of CD4⁺ cell count (<0.20, 0.20-0.49, and 0.50x10⁹/L [<200, 200-499, and 500/µL]) was reduced to a 5-stage classification scheme using a backward stepwise regression procedure. The 5-year cumulative probabilities for AIDS and infectious disease deaths ranged from 0% and 0%, respectively, for group I (viral load, <500 copies/mL; CD4⁺ cell count, 0.50x10⁹/L) to 81.2% and 76.1% respectively, for group V (viral load, 10000 copies/mL; CD4⁺ cell count, 0.20x10⁹/L). Conclusions.— In this study, plasma HIV-1 viral load independently and in combination with CD4⁺ cell count measurements provided powerful prognostic information for progression to AIDS and death caused by infectious disease in a population of predominantly African American IDUs. Combining categories of both markers provided a simple method for prognostically staging HIV disease.      

Rapid HIV-1 testing during labor: a multicenter study

Context  Timely testing of women in labor with undocumented human immunodeficiency virus (HIV) status could enable immediate provision of antiretroviral prophylaxis. Objectives  To determine the feasibility and acceptance of rapid HIV testing among women in labor and to assess rapid HIV assay performance. Design, Setting, and Patients  The Mother-Infant Rapid Intervention At Delivery (MIRIAD) study implemented 24-hour counseling and voluntary rapid HIV testing for women in labor at 16 US hospitals from November 16, 2001, through November 15, 2003. A rapid HIV-1 antibody test for whole blood was used. Main Outcome Measures  Acceptance of HIV testing; sensitivity, specificity, and predictive value of the rapid test; time from blood collection to patient notification of results. Results  There were 91 707 visits to the labor and delivery units in the study, 7381 of which were by eligible women without documentation of HIV testing. Of these, 5744 (78%) women were approached for rapid HIV testing and 4849 (84%) consented. HIV-1 test results were positive for 34 women (prevalence = 7/1000). Sensitivity and specificity of the rapid test were 100% and 99.9%, respectively; positive predictive value was 90% compared with 76% for enzyme immunoassay (EIA). Factors independently associated with higher test acceptance included younger age, being black or Hispanic, gestational age less than 32 weeks, and having had no prenatal care. Lower acceptance was associated with being admitted between 4 PM and midnight, particularly on Friday nights, but this may be explained in part by fewer available personnel. Median time from blood collection to patient notification of result was 66 minutes (interquartile range, 45-120 minutes), compared with 28 hours for EIA (P<.001). Conclusions  Rapid HIV testing is feasible and delivers accurate and timely test results for women in labor. It provides HIV-positive women prompt access to intrapartum and neonatal antiretroviral prophylaxis, proven to reduce perinatal HIV transmission, and may be particularly applicable to higher-risk populations.      

HLA-DR expression on regulatory T cells is closely associated with the global immune activation in HIV-1 infected subjects naïve to antiretroviral therapy

Background  The frequencies of regulatory T cells (Tregs) increased over the HIV infection but its counts actually decreased. We proposed that the decrease of Treg counts may cause the reduction of inhibitory effect and thereby account for the over-activation of Tregs during HIV infection. However, it remains unknown whether Tregs are also over-activated and thereafter the activation induced death may lead to the decrease of Tregs.

Methods  Tregs were defined as CD4⁺CD25⁺CD127^lo/- T cells. Eighty-one HIV-1 infected patients were enrolled in our study, and twenty-two HIV-1 seronegative donors were recruited as the control. The levels of HLA-DR on Tregs were determined by FACSAria flow cytometer.

Results  Compared to HIV-1 seronegative donors, the levels of HLA-DR on CD4⁺CD25⁺CD127^lo/- Tregs were significantly increased in HIV-1 infected patients, and its increase was positively associated with viral loads (r=0.3163, P=0.004) and negatively with CD4 T-cell counts (r=−0.4153, P <0.0001). In addition, significant associations between HLA-DR expression on CD4⁺CD25⁺CD127^lo/- Tregs and the percentages of HLA-DR, CD38, Ki67 expressing CD4⁺ and CD8⁺ T cells were also identified.

Conclusion  HLA-DR on Tregs is a good marker for viral replication and disease progression. The over-activation of Tregs might result in the decrease of Tregs.

     

New Testing Strategy to Detect Early HIV-1 Infection for Use in Incidence Estimates and for Clinical and Prevention Purposes

Context.— Differentiating individuals with early human immunodeficiency virus 1 (HIV-1) infection from those infected for longer periods is difficult but important for estimating HIV incidence and for purposes of clinical care and prevention. Objective.— To develop and validate a serologic testing algorithm in which HIV-1–positive persons with reactive test results on a sensitive HIV-1 enzyme immunoassay (EIA) but nonreactive results on a less sensitive (LS) EIA are identified as having early infection. Design.— Diagnostic test and testing strategy development, validation, and application. Specimens were tested with both a sensitive HIV-1 EIA (3A11 assay) and a less sensitive modification of the same EIA (3A11-LS assay). Settings and Participants.— For assay development: 104 persons seroconverting to HIV-1 comprising 38 plasma donors, 18 patients of a sexually transmitted disease clinic in Trinidad, and 48 participants in the San Francisco Men's Health Study (SFMHS); 268 men without the acquired immunodeficiency syndrome (AIDS) in the SFMHS who had been infected for at least 2.5 years; and 207 persons with clinical AIDS; for testing strategy validation: 488 men in the SFMHS from 1985 through 1990 and 1275449 repeat blood donors at 3 American Red Cross blood centers from 1993 through 1995; and for HIV-1 incidence estimates: 2 717 910 first-time blood donors. We retrospectively identified persons eligible for a study of early infection. Main Outcome Measure.— Ability to identify early HIV infection. Results.— Estimated mean time to being 3A11 reactive/3A11-LS nonreactive was 129 days (95% confidence interval [CI], 109-149 days). Our testing strategy accurately diagnosed 95% of persons with early infection; however, 0.4% (1/268) of men with established infection and 2% (5/207) of persons with late-stage AIDS were misdiagnosed as having early HIV-1 infection. Average yearly incidence estimates in SFMHS subjects were 1.5% per year vs observed average incidence of 1.4 per 100 person-years. Incidence in repeat blood donors using the sensitive/less sensitive assay testing strategy was 2.95 per 100000 per year (95% CI, 1.14-6.53/100000) vs observed incidence of 2.60 per 100000 person-years (95% CI, 1.49-4.21/100000). Overall incidence in first-time blood donors was 7.18 per 100000 per year (95% CI, 4.51-11.20/100000) and did not change statistically significantly between 1993 and 1996. Use of the sensitive/less sensitive testing strategy alone would have identified all 17 persons with antibodies to HIV-1 eligible for a study of early HIV-1 infection and would have increased enrollment. Conclusions.— The sensitive/less sensitive testing strategy provides accurate diagnosis of early HIV-1 infection, provides accurate estimates of HIV-1 incidence, can facilitate clinical studies of early HIV-1 infection, and provides information on HIV-1 infection duration for care planning.      

Frequent Recovery of HIV-1 From Genital Herpes Simplex Virus Lesions in HIV-1-Infected Men

Context.— Genital ulcer disease has been epidemiologically linked as a risk factor in the transmission of the human immunodeficiency virus 1 (HIV-1). While herpes simplex virus 2 (HSV-2) is the most common cause of genital ulcers, no study has systematically evaluated the frequency or titer of HIV-1 virus in HSV-2 lesions. Objective.— To compare lesional HIV-1 RNA levels during and after genital HSV-2 reactivation and to evaluate the frequency, titer, and duration of HIV-1 RNA shedding in lesions due to HSV-2. Design.— Convenience sample. Setting.— Sexually transmitted disease research clinic at the University of Washington, Seattle. Patients.— Twelve HIV-infected men with a history of symptomatic HSV-2 infection who underwent daily sampling of genital lesions for HIV-1 RNA by polymerase chain reaction assay and HSV-2 by culture. Main Outcome Measure.— Detection of lesional HIV RNA and HSV-2. Results.— HIV-1 RNA was detected from lesional swabs in 25 of 26 consecutively studied HSV-2 episodes and on 67% of days in which genital lesions were noted. The HIV-1 RNA titers in lesional swabs exceeded 10000 copies/mL of swab sample in 75% of samples (range, 2.2-3.2x10⁵ copies/mL of swab sample). HIV-1 RNA in genital lesion swabs was seen in persons with high and low titers of plasma HIV-1 RNA and was not associated with plasma HIV-1 RNA levels. Conclusions.— HIV-1 virions can consistently be detected in genital ulcers caused by HSV-2, which suggests that genital herpes infection likely increases the efficiency of the sexual transmission of HIV-1.      

A Randomized, Double-blind Trial Comparing Combinations of Nevirapine, Didanosine, and Zidovudine for HIV-Infected Patients: The INCAS Trial

Context.— Current guidelines recommend that individuals infected with the human immunodeficiency virus type 1 (HIV-1) be treated using combinations of antiretroviral agents to achieve sustained suppression of viral replication as measured by the plasma HIV-1 RNA assay, in the hopes of achieving prolonged remission of the disease. However, until recently, many drug combinations have not led to sustained suppression of HIV-1 RNA. Objective.— To compare the virologic effects of various combinations of nevirapine, didanosine, and zidovudine. Design.— Double-blind, controlled, randomized trial. Setting.— University-affiliated ambulatory research clinics in Italy, the Netherlands, Canada, and Australia (INCAS). Patients.— Antiretroviral therapy–naive adults free of the acquired immunodeficiency syndrome with CD4 cell counts between 0.20 and 0.60x10⁹/L (200-600/µL). Intervention.— Patients received zidovudine plus nevirapine (plus didanosine placebo), zidovudine plus didanosine (plus nevirapine placebo), or zidovudine plus didanosine plus nevirapine. Main Outcome Measure.— Plasma HIV-1 RNA. Results.— Of the 153 enrolled patients, 151 were evaluable. At week 8, plasma HIV-1 RNA levels had decreased by log 2.18, 1.55, and 0.90 in the triple drug therapy, zidovudine plus didanosine, and zidovudine plus nevirapine groups, respectively (P<.05). The proportions of patients with plasma HIV-1 RNA levels below 20 copies per milliliter at week 52 were 51%, 12%, and 0% in the triple drug therapy, zidovudine plus didanosine, and zidovudine plus nevirapine groups, respectively (P<.001). Viral amplification was attempted in 59 patients at 6 months. Viral isolation was unsuccessful in 19 (79%) of 24, 10 (53%) of 19, and 5 (31%) of 16 patients in the triple drug therapy, zidovudine plus didanosine, and zidovudine plus nevirapine groups, respectively. Among patients from whom virus could be amplified, resistance to nevirapine was found in all 11 patients receiving zidovudine plus nevirapine and in all 5 patients receiving triple drug therapy. Rates of disease progression or death were 23% (11/47), 25% (13/53), and 12% (6/51) for the zidovudine plus nevirapine, zidovudine plus didanosine, and triple drug therapy groups, respectively (P=.08). Conclusions.— Triple drug therapy with zidovudine, didanosine, and nevirapine led to a substantially greater and sustained decrease in plasma viral load than the 2-drug regimens studied. Our results also suggest that suppression of viral replication, as demonstrated by a decrease in the plasma HIV-1 RNA load below the level of quantitation of the most sensitive test available, may at least forestall the development of resistance.      

Prevalence of HIV-1 in blood donations following implementation of a structured blood safety policy in South Africa

Context  The South African National Blood Service collects more than 700 000 units of blood annually from a population in which 11.4% is infected with human immunodeficiency virus 1 (HIV-1). The prevalence of HIV-1 in blood donations increased to 0.26% (1:385) in 1998, indicating that a significant number of window-period infective units were entering the blood supply (risk 3.4/100 000). Objectives  To determine whether the implementation of a new donor selection policy and educational program introduced in 1999 was associated with reductions in the incidence and prevalence of HIV-1 in blood donations and the reduced transmission risk. Design  We compared the prevalence of HIV-1 in 880 534 blood donations collected from 1999 through 2000 with the 791 639 blood donations collected from 2001 through 2002. We estimated the incidence of HIV-1 in 93 378 (1999-2000) and 67 231 (2001-2002) first-time donations and the residual risk for all donations in 2001-2002 using the less-sensitive enzyme-linked immunoassay and incidence-window period model. Setting  All blood donors in the Inland region of the South African National Blood Service were analyzed. Intervention  Donor clinics in high HIV prevalence areas were closed. Programs targeting repeat donors and youth were initiated and HIV risk behavior education programs were developed. Structured donor interviews and an enhanced donor self-exclusion questionnaire were institutionalized. Results  The prevalence of HIV-1 in blood donations declined from 0.17% in 1999-2000 to 0.08% in 2001-2002 after the implementation of the new donor selection and education policy. The number of high-risk donations collected decreased from 2.6% to 1.7% (P<.001), and the likelihood of these donations being infected decreased from 4.8% to 3.25%. The likelihood of first-time donors being recently infected with HIV-1 decreased from 18% to 14% (P = .07) and respective incidence of high-risk donations collected decreased from 2.6% to 1.7%. Donations from the majority black population declined from 6.6% to 4.2% (P<.001). Analysis of HIV-1 incidence in 2001-2002 suggests a residual risk of collecting a window period infectious unit of 2.6/100 000. Conclusion  The implementation of enhanced education and selection policies in South Africa was associated with decreased prevalence of HIV-1 in blood donations.