Evaluation of the sensitivity and specificity of six HIV combined p24 antigen and antibody assays

The contemporary immunoassays for HIV diagnosis: a concise overview

Recent advances in human immunodeficiency virus (HIV) diagnostics have improved the management of disease progression significantly, which have also boosted the efficacy of antiviral therapies. The detection of HIV at the earliest is very important. A highly recognized and effective virological biomarker for acute HIV infections is p24 antigen. This brief overview is based on advances of HIV diagnosis while focusing on the latest HIV testing technologies including HIV-specific antigens detecting assays of both anti-HIV antibodies and p24 antigen. In addition to other emerging molecular diagnostics for acute HIV infection, the utilization of p24 antigen has been summarized. Moreover, it has been explained how these immunoassays have reduced the window period for detection of HIV in the acute stage of infection.

Evaluation of the bioMérieux VIDAS HIV Duo Quick and Anti-HCV assays for dried blood spot based serosurveillance

Serosurveillance is central to monitoring our progress towards HIV and HCV elimination targets proposed for 2030. However, serosurveillance systems are ineffective without reliable serological assays for the detection of HIV and HCV antibodies. Assays should also be compatible with dried blood spot (DBS) samples to facilitate biological sample collection. The VIDAS HIV Duo Quick and Anti-HCV assays are sold as reagents strips and processed by the automated VIDAS benchtop immunoanalyser. While both assays have shown excellent performance in serum and plasma, performance data in DBS samples is lacking. In our study, we evaluate the performance of the VIDAS HIV Duo Quick and Anti-HCV assays in DBS (n = 725) collected during a cross-sectional serosurvey (the Transitions study). The VIDAS HIV Duo quick had a sensitivity and specificity of 94.5% (95% CI 85.1%, 98.5%) and 95.7% (95% CI 93.9%, 97.0%) respectively. Likewise, the VIDAS Anti-HCV had a sensitivity and specificity of 95.6% (95% CI 91.6%, 97.8%) and 95.6% (95% CI 93.5%, 97.0%) respectively. These assays are unlikely to be helpful in low-prevalence settings due to sub-optimal performance, but their performance could likely be improved by optimizing DBS elution protocols which was, unfortunately, not possible during our study.

Screening for Human Immunodeficiency Virus Infection by Use of a Fourth-Generation Antigen/Antibody Assay and Dried Blood Spots: In-Depth Analysis of Sensitivity and Performance Assessment in a Cross-Sectional Study

We evaluated the performance of a fourth-generation antigen/antibody (Ag/Ab) assay for detecting HIV-1 infection on dried blood spots (DBS) both in a conventional laboratory environment and in an epidemiological survey corresponding to a real-life situation. Although a 2-log loss of sensitivity compared to that with plasma was observed when using DBS in an analytical analysis, the median delay of positivity between DBS and crude serum during the early phase postacute infection was 7 days. The performance of the fourth-generation assay on DBS was approximately similar to that of a third-generation (antibody only) assay using crude serum samples. Among 2,646 participants of a cross-sectional study in a population of men having sex with men, 428 DBS were found reactive, but negative results were obtained from 5 DBS collected from individuals who self-reported a positive HIV status, confirmed by detection of antiretroviral (ARV) drugs in their DBS. The data generated allowed us to estimate a sensitivity of 98.8% of the fourth-generation assay/DBS strategy in a high-risk population, even including a broad majority of individuals on ARV treatment among those HIV positive. Our study brings additional proofs that DBS testing using a fourth-generation immunoassay is a reliable strategy able to provide alternative approaches for both individual HIV testing and surveillance of various populations.

Nucleic acid testing and molecular characterization of HIV infections

Significant advances have been made in the molecular assays used for the detection of human immunodeficiency virus (HIV), which are crucial in preventing HIV transmission and monitoring disease progression. Molecular assays for HIV diagnosis have now reached a high degree of specificity, sensitivity and reproducibility, and have less operator involvement to minimize risk of contamination. Furthermore, analyses have been developed for the characterization of host gene polymorphisms and host responses to better identify and monitor HIV-1 infections in the clinic. Currently, molecular technologies including HIV quantitative and qualitative assays are mainly based on the polymerase chain reaction (PCR), transcription-mediated amplification (TMA), nucleic acid sequence-based amplification (NASBA), and branched chain (b) DNA methods and widely used for HIV detection and characterization, such as blood screening, point-of-care testing (POCT), pediatric diagnosis, acute HIV infection (AHI), HIV drug resistance testing, antiretroviral (AR) susceptibility testing, host genome polymorphism testing, and host response analysis. This review summarizes the development and the potential utility of molecular assays used to detect and characterize HIV infections.

Risk stratification of HIV infection for patients needing molecular confirmation with the Abbott 4th generation Architect System

BACKGROUND

Some patients need their 4^th generation HIV testing results confirmed with molecular testing after primary confirmatory testing which may not be immediately available. Further risk stratification of these patients pending the results of molecular testing may be of value not only for patient counseling but also for treatment of women in labor.

OBJECTIVES

To determine the risk of a positive test result on molecular testing for these patients.

STUDY DESIGN

The risk of a positive molecular test result for patients with a result needing molecular confirmation on a 4th generation HIV testing algorithm (Abbott Architect, Multispot/Geenius confirmatory test) was stratified based on the patient's white blood cell (WBC) count and the magnitude of Architect result Signal Cut Off ratio (S/CO).

RESULTS

A total of 61,666 patients were tested with 658 (1.1%) positive results and 76 (0.12%) patients needing molecular confirmation. Patients with an S/CO of <5 or an S/CO of 5-100 with a WBC > 6.5 × 10 ⁹ cells/l had a significantly lower risk of a positive molecular HIV test (0/48, 0%) than patients with an S/CO 5-100 with a WBC < 6.0 s × 10 ⁹ cells/l (5/9, 56%, p < .001) or an S/CO > 100 (2/2, 100%, p < .001). Pregnant women had a significantly lower rate of positive test results (24/6924, 0.4%) than non-pregnant patients (634/54742, 1.1%, p < 0.001). All 12 cases needing molecular confirmation in pregnant women had negative NAT test results.

CONCLUSIONS

Patients who need their HIV results confirmed with molecular testing using a 4^th generation algorithm that includes the Abbott Architect System can be further stratified into low, intermediate, and high risk groups based on additional laboratory information pending the results of molecular testing. This risk stratification may be of value for patient counseling and treatment of women in labor.

HIV infection in Xi'an, China: epidemic characterization, risk factors to false positives and potential utility of the sample-to-cutoff index to identify true positives using Architect HIV Ag/Ab combo

Background

In China, although tremendous efforts has been made, the HIV/AIDS is still not controlled.

Objectives

The study was carried out to determine the epidemic of HIV infection in Xi'an, analyse false positives (FP) risk factors and potential utility of sample-to-cutoff index to identify true positives using Architect HIV Ag/Ab Combo.

Methods

A retrospective review for HIV screening by Architect HIV Ag/Ab Combo was performed in a teaching hospital in Xi'an between 2015 and 2016. The prevalence of HIV, positive predictive value (PPV) at different cut-off indexices (COI) were calculated. The epidemic of infections and risk factors for FP results were investigated.

Results

In the study, the HIV prevalence and FP rate of Architect HIV Ag/Ab Combo were 0.076 and 46.08%, respectively. The Han Chinese, males and people aged < 40 years accounted for the majority of infections (98.29, 76.07 and 73.5%, respectively). 85.47% of the infections were transmitted through sexual contact (35.04% of male homosexual and 50.43% of heterosexual). COI at 1-10, 10-30 and ≥ 30, the PPVs were 0, 50 and 100%, respectively. The independent risk factors for FP, i.e., pregnancy and malignancy had a statistically significant association with FP (p < 0.05), and age had a very strong statistically significant association with FP (p < 0.001).

Conclusions

In Xi'an, sexual contact was the most important transmission mode for HIV, and the infections were predominantly identified in Han Chinese, males, young and middle-aged people. For Architect HIV Ag/Ab Combo, it can achieve 100% of PPV with COI ≥30, and the age was strongly statistically associated with FP.

Hybrid magneto-plasmonic liposomes for multimodal image-guided and brain-targeted HIV treatment

Image-guided drug delivery is an emerging strategy in the field of nanomedicine. The addition of image guidance to a traditional drug delivery system is expected to achieve highly efficient treatment by tracking the drug carriers in the body and monitoring their effective accumulation in the targeted tissues. In this study, we developed multifunctional magneto-plasmonic liposomes (MPLs), a hybrid system combining liposomes and magneto-plasmonic nanoparticles for a triple-modality image-guided drug delivery. Tenofovir disoproxil fumarate, an antiretroviral drug used to treat human immunodeficiency virus type 1 (HIV-1), was encapsulated into the MPLs to enable the treatment in the brain microenvironment, which is inaccessible to most of the drugs. We found strong negative and positive contrasts originating from the magnetic core of MPLs in magnetic resonance imaging (MRI) and magnetic particle imaging (MPI), respectively. The gold shell of MPLs showed bright positive contrast in X-ray computed tomography (CT). MPLs achieved enhanced transmigration across an in vitro blood-brain barrier (BBB) model by magnetic targeting. Moreover, MPLs provided desired therapeutic effects against HIV infected microglia cells.

Epitope Mapping of the Antibody Response Against the Envelope Proteins of the Feline Foamy Virus

Foamy viruses (FV) are retroviruses that infect several species without pathological signs, but induce substantial antibody responses in the infected host. In the case of feline FV (FFV), antibodies against Gag, Bet, and Env have been used to indicate infection; however, it is unclear whether the response to specific epitopes correlates with immunity. Here, we investigated the epitope specificity of antibodies targeting the Env protein using peptide microarrays. Sera from naturally and experimentally FFV-infected cats and pumas and from rats immunized with FFV Env expression plasmids were analyzed. An immunodominant epitope was identified in the Env leader protein (Elp), and a strong reactivity to two epitope clusters in the transmembrane (TM) subunit of Env was observed. Moreover, a short stretch of residues in the C-terminal part of the surface (SU) protein was found to be significantly associated with FFV serotype FUV-mediated neutralization. Taken together, our results add a new level of detail on the B cell epitope repertoire induced during FFV infection. Furthermore, our results provide a basis for current attempts to modify FV vectors to express and present vaccine epitopes for the directed induction of humoral immunity.

Point-Of-Care p24 Infant Testing for HIV May Increase Patient Identification despite Low Sensitivity

The long delay in returning test results during early infant diagnosis of HIV (EID) often causes loss-to-follow-up prior to antiretroviral treatment (ART) initiation in resource-limited settings. A point-of-care (POC) test may help overcome these challenges. We evaluated the performance of the LYNX p24 Antigen POC test in Mozambique. 879 HIV-exposed infants under 18 months of age were enrolled consecutively at three primary healthcare clinics (PHC). Lancet heel-drawn blood was tested on-site by nurses using a prototype POC test for HIV Gag p24 antigen detection. Results of POC testing were compared to laboratory-based nucleic acid testing on dried blood spots. A comparison of the effect of sensitivity and timely test results return on successful diagnosis by POC and laboratory-based platforms was also calculated. The sensitivity and specificity of the LYNX p24 Ag test were 71.9%; (95% confidence interval [CI]: 58.5-83.0%) and 99.6% (95% CI: 98.9-99.9%), respectively. The predictive value of positive and negative tests were 93.2% (95% CI: 81.3-98.6%) and 97.9% (95% CI: 96.8-98.8%), respectively. Overall agreement was high (Cohen Kappa = 0.80; 95% CI: 0.71-0.89). Despite its lower sensitivity, the POC test had the potential to provide test results to up to 81% more patients compared to the laboratory-based test. This prototype POC p24 assay was feasible for use in PHCs but demonstrated low sensitivity for HIV detection. POC EID technologies that perform below standard recommendations may still be valuable diagnostic tools in settings with inefficient EID networks.

Seroprevalence of human immunodeficiency virus, hepatitis B and C viruses, and Treponema pallidum infections among blood donors at Shiyan, Central China

Background

Ordinary screening of transfusion-transmissible infections (TTIs) among blood donors is essential for blood transfusion. Although there is several TTIs studies focus on human immunodeficiency virus, hepatitis B and C viruses, and Treponema pallidum infections in China, it is no data to illustrate any firm conclusion from Shiyan City, Central China. It aims to verify the seroprevalence of TTIs among blood donors at Shiyan.

Methods

A retrospective analysis of blood donors’ information was conducted for the presence of HIV, HBV, HCV and T. pallidum. Logistic regression analysis was used to demonstrate risk factors including age, gender and occupation associated with them. The variation tendency in seroprevalence of these TTIs over the study period was evaluated by Cochran-Armitage trend test.

Results

Of 211 639 blood donors, 2 858 (1.35 %) had serological evidence of TTIs. The seroprevalence of HIV, HBV, HCV and T. pallidum were 0.08 %, 0.51 %, 0.20 % and 0.57 %, respectively. However, the co-infection prevalence of TTIs has not been detected. The HIV seropositivity significantly increased among female donors (OR = 1.63, P < 0.001) and farmers (OR = 2.02, P = 0.020). Significantly increased HBV seropositivity was only observed framers (OR = 1.87, P <0.001) compared to workers. Analogously, significantly increased HCV seropositivity was observed among farmers (OR = 2.59, P < 0.001), students (OR = 2.43, P < 0.001), merchants (OR = 1.70, P = 0.014) and others (OR = 1.78, P =0.001). The T. pallidum seroprevalence was notably increased among female (OR = 1.54, P < 0.001), and farmers (OR = 1.70, P <0.001). Moreover, significantly increasing trends of HIV (Z = −6.88, P < 0.01), HBV (Z = −4.52, P < 0.01), HCV (Z = −4.16, P < 0.01) and T. pallidum (Z = −1.36, P < 0.01) seropositivity were observed over the study period.

Conclusions

It originally offers a substantial prevalence of TTIs among blood donors at Shiyan, Central China. Severe blood donor selection and all-inclusive screening of blood are highly recommended. It might be helpful for developing and updating guidance for blood safety.

Trial registration

Retrospectively registered.

Initiation of Antiretroviral Therapy During Acute HIV-1 Infection Leads to a High Rate of Nonreactive HIV Serology

BACKGROUND

Third- and fourth-generation immunoassays (IAs) are widely used in the diagnosis of human immunodeficiency virus (HIV) infection. Antiretroviral therapy (ART) during acute HIV infection (AHI) may impact HIV-specific antibodies, with failure to develop antibody or seroreversion. We report on the ability of diagnostic tests to detect HIV-specific antibodies in Thai participants initiating ART during AHI.

METHODS

Participants with detectable plasma HIV RNA but nonreactive HIV-specific immunoglobulin G, enrolled in an AHI study, were offered immediate initiation of ART. Participants were tested at initiation and at 12 and 24 weeks following treatment using standard second-, third-, and fourth-generation IAs and Western blot (WB).

RESULTS

Participants (N = 234) initiating ART at a median of 19 days (range, 1-62 days) from HIV exposure demonstrated different frequencies of reactivity prior to and following 24 weeks of ART depending on the IA. Third-generation IA nonreactivity prior to ART was 48%, which decreased to 4% following ART (P < .001). Fourth-generation IA nonreactivity was 18% prior to ART and 17% following ART (P = .720). Negative WB results were observed in 89% and 12% of participants prior to and following 24 weeks of ART, respectively (P < .001). Seroreversion to nonreactivity during ART was observed to at least one of the tests in 20% of participants, with fourth-generation IA demonstrating the highest frequency (11%) of seroreversion.

CONCLUSIONS

HIV-specific antibodies may fail to develop and, when detected, may decline when ART is initiated during AHI. Although fourth-generation IA was the most sensitive at detecting AHI prior to ART, third-generation IA was the most sensitive during treatment.

CLINICAL TRIALS REGISTRATION

NCT00796146 and NCT00796263.

The Performance of the Abbott i2000 for Measuring Serum Markers of Infectious Diseases

BACKGROUND

To date, there is a trend that the chemiluminescent microparticle immunoassays (CMIA) and electrochemiluminescence immunoassays (ECIA) technology gradually replacing the enzyme-linked immunosorbent assay (ELISA). But the performance such as the limit of quantitation (LOQ), precision, linear range of CMIA, or ECIA for serum markers of infectious diseases has rarely been reported.

METHODS

Using proficiency testing samples and standard materials, we confirmed the LOQ of the ELISA and the precision, linear range, LOQ, and instrument biases of the Abbott i2000 for eight serum markers. We used the Abbott i2000 and ELISAs to assess five HIV samples; the researchers were blinded to the true status of the samples.

RESULTS

For the Abbott i2000, the coefficients of variation (CV) for the low, medium, and high concentration samples ranged from 1.06 to 12.74%, which were less than the allowable error; the linear ranges of HBsAg and HBsAb were 0.66-304.11 IU/ml and 8.16-1205.9 mIU/ml, respectively. For the Abbott i2000, the LOQs of HBsAg, HBsAb, HBeAg, HBeAb, HBcAb, anti-HCV, anti-TP, and anti-HIV were 0.026 IU/ml, 4 mIU/ml, 0.14 NCU/ml, 0.56 NCU/ml, 0.99 NCU/ml, 0.5 NCU/ml, 8.8 mIU/ml, and 1.92 NCU/ml, respectively, and these values were 0.16 IU/ml, 6.97 mIU/ml, 1.16 NCU/ml, 1.63 NCU/ml, 1.79 NCU/ml, 1.03 NCU/ml, 8.33 mIU/ml, and 1.3 NCU/ml, respectively, for the ELISA. When five HIV samples were blindly assessed, two cases were missed by the Abbott i2000 and the ELISA results were consistent with the expected results.

CONCLUSIONS

The Abbott i2000 performed significantly better than the ELISA on HBV and HCV screening; however, for anti-TP and anti-HIV, the ELISA remained the preferred method.

The prevalence of HIV in the sudden, unexplained and unexpected death population at the Pretoria Medico-Legal Laboratory

Purpose

To determine the prevalence of HIV in the sudden, unexplained and unexpected (SUU) death population admitted to the Pretoria Medico-Legal Laboratory.

Methods

This study was conducted at the Pretoria Medico-Legal Laboratory. Blood samples were obtained from decedents who died suddenly and/or unexpectedly, during autopsy, by a forensic pathologist. Sample collection continued until 100 valid samples were analysed for HIV antibodies. The data collected included demographic details and case-related information.

Results and Conclusion

SUU deaths accounted for 14% of all cases admitted to the Pretoria Medico-Legal Laboratory. The HIV prevalence in the SUU deaths was 43%, which is 17% higher than the general mortuary population in Pretoria (p = 0.0045). The majority of these deaths were due to respiratory disease processes, with 12 cases having HIV/TB co-infection.

Fourth generation assays for HIV testing

INTRODUCTION

Laboratory diagnosis of HIV infection is essential for the prevention of infection and the identification of infected individuals who could benefit from highly active antiretroviral therapy. Since the release of the first assays for the detection of anti-HIV antibodies, the technology of immunoassays has improved.

AREAS COVERED

Fourth generation assays - simultaneously detecting HIV p24 antigen and antibodies - have been developed and have been a major improvement in the detection of HIV infection, with a reduction of the diagnostic window. Studies have provided definite evidence for their clinical utility. Combination assays with separate results for anti-HIV antibodies and p24 antigen have been developed. Expert Commentary: In conclusion, fourth generation assays are an effective tool for the laboratory diagnosis of HIV infection. The ADVIA Centaur HIV Ag/Ab Combo assay is in line with most recent fourth generation assays and its clinical utility has been assessed.

Spectrum of false positivity for the fourth generation human immunodeficiency virus diagnostic tests

Novel fourth generation screening and confirmatory human immunodeficiency virus (HIV) assays are now commercially available and incorporated into new diagnostic algorithms. We report two cases involving a total of three patients which highlight the spectrum of false positivity for both the Abbott Architect p24 antigen/antibody assay and the confirmatory Multispot antibody differentiation test. We then discuss the mechanisms for false positivity and the associated clinical conditions or laboratory scenarios that may predispose to inaccurate interpretation.

Evaluation of performance of human immunodeficiency virus antigen/antibody combination assays in Taiwan

BACKGROUND

The fourth-generation human immunodeficiency virus (HIV) combination assay, which can simultaneously detect the presence of anti-HIV antibody and HIV antigen, has been shown to shorten the window period in HIV diagnosis compared with the third-generation HIV antibody immunoassay. This study was aimed to determine the performance of HIV combination assays in Taiwan, where the HIV-1 seroprevalence is 0.007% and HIV-2 infection has never been reported.

METHODS

Performance of three fourth-generation HIV Ag/Ab combination assays (Dia.Pro, Wantai, and Bio-Rad) and one third-generation HIV Ab immunoassay (AxSYM HIV 1/2 gO) was assessed.

RESULTS

A total of 152 specimens, including 86 confirmed HIV-seropositive and 66 HIV-seronegative samples, were used in the study. The sensitivity of four assays varied from 98.8% to 100%, and specificity varied from 98.5% to 100%. Performance of the 75 equivocal samples, the HIV status of which was confirmed later, in terms of negative prediction varied from 81.8% to 87.5%. The Bio-Rad and Dia.Pro assays exhibited higher sensitivity for the detection of p24 antigen among the three fourth-generation HIV combination assays.

CONCLUSION

The three fourth-generation HIV Ag/Ab combination assays exhibited better sensitivity, specificity, and negative prediction than the third-generation HIV Ab immunoassay.

Evaluation of an antigen-antibody "combination" enzyme linked immunosorbent assay for diagnosis of hepatitis C virus infections

Background

Development of “combination” assays detecting in parallel, within a single test, Hepatitis C Virus (HCV) antigens and antibodies, not only reduces the window period in HCV-infection but also costs. Reduction of costs is important for developing countries where money and personal resources are limited.

Methods

We compared the Monolisa® HCV Antigen-Antibody Ultra (Bio-Rad Laboratories Limited, Marnes La Coquette, France) with the AXSYM HCV version 3.0 (Abbot Diagnostics, Germany)-the latter assay detecting only antibodies to HCV. Seventy three HCV-PCR positive and negative samples were tested.

Results

Although the two assays showed comparable results, two samples from a bone marrow transplant (BMT) patient of viral loads 7.8 × 10₅ and 8.9 × 10₆ IU/mL could not be detected by the Monolisa® HCV Antigen-Antibody Ultra assay. Failure to detect the two samples with viral loads considered above threshold of detection for antigen proteins suggested a lack of sensitivity by this assay to discover viral capsid protein in patient samples. Genotyping of these samples revealed genotype 1b, a HCV-subtype which is widespread and should thus be easily detected.

Conclusion

We conclude that although this assay depicts high sensitivity and specificity in detecting antibodies to HCV, it seems not to add further benefit in our study population to detect HCV infections by enhanced sensitivity due the potential contingency to trace viral capsid antigens.

Evaluation of HIV antigen/antibody combination ELISAs for diagnosis of HIV infection in Dar Es Salaam, Tanzania

INTRODUCTION

The aim of this study was to evaluate the performance of Enzygnost HIV Integral II antigen/antibody combination ELISAs in order to formulate HIV ELISA testing algorithms for the Ministry of Health and Social Welfare, Tanzania.

METHODS

This was a laboratory-based evaluation of Enzygnost HIV Integral II Antibody/ Antigen, Murex HIV antigen/antibody and Vironostika HIV Uniform II antigen/antibody conducted between October 2011 and May 2012.

RESULTS

A total of 600 blood samples were included in the evaluation. A total of 209/596 (35.1%) serum samples were confirmed HIV positive. Of these, the prevalence of HIV infection was 2.3% (3/130), 2.3% (3/127), 2.2% (3/139) and 100% (200/200) for VCT clients, ANC attendees, blood donors and CTC patients, respectively. Three hundred and eighty seven (64.9%) were HIV negative samples. Sensitivity was 100% (95% CI; 98.3-100%) for all the three HIV ELISAs. The specificity for the Enzygnost HIV Integral II and Murex was 100% (95% CI; 99.1-100%). The final specificity at repeat testing was 99.5% (95% CI; 98.2-99.9%) for Vironostika. Enzygnost HIV Integral II detected HIV infection seven days since first bleed.

CONCLUSION

Initial testing using either Vironostika or Murex HIV antigen/antibody combination ELISA followed by testing of reactive samples on the Enzygnost HIV Integral II gave a sensitivity and specificity of 100% with reduced window period. Combination of two HIV antigen/antibody combination ELISAs can be used as an alternative confirmatory testing strategy for screening of donated blood at the National and Zonal blood transfusion centres and in lab diagnosis of HIV infection.

Prolonged second diagnostic window for human immunodeficiency virus type 1 in a fourth-generation immunoassay: are alternative testing strategies required?

Diagnosis of acute HIV is done by patient history and examination and testing of RNA, proviral DNA, and serology using fourth-generation antigen/antibody detection assays. We describe an HIV-1 primary infection with a second diagnostic window of 18 to 34 days on a fourth-generation immunoassay, which would have been missed using some current algorithms. Caution must be exercised when fourth-generation HIV-1 immunoassays are interpreted in isolation, and additional testing should be considered depending on patient risk assessment.

Evaluation of the clinical effectiveness of HIV antigen/antibody screening using a chemiluminescence microparticle immunoassay

Human immunodeficiency virus (HIV) screening assays have improved from single-antigen detection to detection of antigen-antibody combinations. However, concerns have been raised over the potential for false-positive results in antigen-antibody combination assays. The present study investigated the clinical effectiveness of HIV antigen/antibody (HIV Ag/Ab) combination screening by chemiluminescence microparticle immunoassay (CMIA) in over 88,000 samples from an HIV low-prevalence area of Beijing, China. The HIV Ag/Ab CMIA screening results were consistent with those obtained by Western blot and HIV-RNA testing, and had an accuracy of 99.74% (Kappa index=0.98). False-positive results were more common for women affected by clinical interfering factors (e.g., kidney disease, tumors) than for men (80.95% vs. 15.09%, P<0.001). When CMIA signal-to-cutoff ratio (S/CO) was 11.26, the sensitivity and specificity were highest (100%, 99.43%), and the area under the ROC curve (AUC) was 0.998. Specimens that were negative by CMIA (S/CO <1) were all negative by HIV-RNA testing. These results indicate that HIV Ag/Ab CMIA has a good clinical performance; however, some clinical interfering factors should be considered in HIV low-prevalence areas for their potential to skew testing results.

New automated chemiluminescence immunoassay for simultaneous but separate detection of human immunodeficiency virus antigens and antibodies

The recently launched Liaison XL Murex HIV Ab/Ag assay (DiaSorin S.p.A) uses chemiluminescence immunoassay technology for the combined qualitative determination of p24 antigen of HIV-1 and specific antibodies to both HIV-1 and HIV-2. We studied 571 serum samples from those submitted to our laboratory for HIV screening. The samples were divided into 3 subsets: subset A, 365 samples collected prospectively during 1 week; subset B, 158 samples from confirmed HIV-positive patients; and subset C, 48 samples with a positive screening result but a negative or indeterminate confirmatory test result. Our standard screening/confirmatory algorithm was used as a reference. In subset A (prospective), 5 samples were positive and 360 negative by the standard procedure. Liaison XL Murex HIV Ab/Ag correctly identified all 5 positive samples (100%) and 357 negative samples (99.2%). In subset B (confirmed positive), all 158 positive samples were in total agreement in both procedures. In subset C (screen positive only), Liaison XL Murex HIV Ab/Ag yielded accurate results in 42 out of 48 samples (87.5%). Global sensitivity and specificity for Liaison XL Murex HIV Ab/Ag (all subsets included) were 98.3% and 98.5%, respectively. Considering only nonselected prospective samples and confirmed positive samples (subsets A and B), the corresponding sensitivity and specificity values were 100% and 99.2%, respectively. The new fully automated HIV screening test showed high sensitivity and specificity compared to our standard algorithm. Its added advantage of being able to detect HIV-1 and HIV-2 antibodies and p24 antigen separately could prove useful in the diagnosis of early infections.

Point of Care Technologies for HIV

Effective prevention of HIV/AIDS requires early diagnosis, initiation of therapy, and regular plasma viral load monitoring of the infected individual. In addition, incidence estimation using accurate and sensitive assays is needed to facilitate HIV prevention efforts in the public health setting. Therefore, more affordable and accessible point-of-care (POC) technologies capable of providing early diagnosis, HIV viral load measurements, and CD4 counts in settings where HIV is most prevalent are needed to enable appropriate intervention strategies and ultimately stop transmission of the virus within these populations to achieve the future goal of an AIDS-free generation. This review discusses the available and emerging POC technologies for future application to these unmet public health needs.

Non-M variants of human immunodeficiency virus type 1

The AIDS pandemic that started in the early 1980s is due to human immunodeficiency virus type 1 (HIV-1) group M (HIV-M), but apart from this major group, many divergent variants have been described (HIV-1 groups N, O, and P and HIV-2). The four HIV-1 groups arose from independent cross-species transmission of the simian immunodeficiency viruses (SIVs) SIVcpz, infecting chimpanzees, and SIVgor, infecting gorillas. This, together with human adaptation, accounts for their genomic, phylogenetic, and virological specificities. Nevertheless, the natural course of non-M HIV infection seems similar to that of HIV-M. The virological monitoring of infected patients is now possible with commercial kits, but their therapeutic management remains complex. All non-M variants were principally described for patients linked to Cameroon, where HIV-O accounts for 1% of all HIV infections; only 15 cases of HIV-N infection and 2 HIV-P infections have been reported. Despite improvements in our knowledge, many fascinating questions remain concerning the origin, genetic evolution, and slow spread of these variants. Other variants may already exist or may arise in the future, calling for close surveillance. This review provides a comprehensive, up-to-date summary of the current knowledge on these pathogens, including the historical background of their discovery; the latest advances in the comprehension of their origin and spread; and clinical, therapeutic, and laboratory aspects that may be useful for the management and the treatment of patients infected with these divergent viruses.

Screening of HIV infection: role of molecular and immunological assays

Due to technical improvements and new developments of immunological assays, the reliability of serological laboratory diagnosis of HIV infection has improved considerably and the residual risk, due to the diagnostic window for transfusion-transmitted HIV, has been reduced significantly. Through the addition of nucleic acid amplification tests (NAT) to blood donor screening, the residual risk can de further decreased by up to 50%, depending on the sensitivity of the NAT protocol and whether individual or pooled blood donations are screened. In-house and commercially available NAT have been implemented in blood banks as HIV only or multiplexed HIV and hepatitis B or C virus assays. As an alternative to separate antigen and antibody screening, combined fourth-generation assays have been developed in 1997, and have achieved a high degree of sensitivity and specificity. Thus, they can replace stand-alone antigen and third-generation antibody assays. While they are used in the routine diagnostics of HIV infection in many countries throughout the world, they probably represent no alternative for NAT in blood-donor screening in industrialized countries. In the next few years, technical improvements will further simplify NAT screening. While there is still some potential to improve the detection threshold of NAT, the sensitivity of the antigen module of fourth-generation assays (a lowest concentration of 3-5 pg of p24 antigen) is probably very close to its technical limit.

How safe is safe: new human immunodeficiency virus Type 1 variants missed by nucleic acid testing

BACKGROUND

Nucleic acid amplification techniques (NAT) in routine blood donor screening considerably reduce the diagnostic window phase period. Nevertheless, several reports of false-negative NAT results were published. Here, four cases of human immunodeficiency virus Type 1 (HIV-1) RNA-positive blood donations that escaped detection by NAT screening are described.

STUDY DESIGN AND METHODS

A total of 2.7 million blood donations were screened for viral infections between January 2010 and October 2012 in our German Red Cross blood donation service. Four plasma specimens with false-negative NAT results were comparatively investigated with 12 CE-marked NAT assays. In two cases of putative HIV-1 variants the target region of the NAT assay was sequenced allowing comparison with the respective primers and probes.

RESULTS

Most of the NAT assays used in routine blood donor screening with the 5'-long terminal repeat (LTR) as target region demonstrated deficiencies in detecting the viral variants and the low-viral-carrier donations. Sequence analysis revealed in one case a deletion of 56 nucleotides within the 5'-LTR preventing the binding of the probe accompanied by a neighbored insertion of another 52 nucleotides and several primer mismatches in another case. No false-negative results were obtained for these cases using dual-target assays. The viral load of the remaining two false-negative results was below the NAT's limit of detection.

CONCLUSION

HIV-1 is characterized by a high mutation rate and rapid generation of new viral variants. By the use of one target region for HIV-1 NAT assays there is a certain risk of false-negative results. Employing HIV-1 multi- and dual-target assays in routine blood donor screening seems to be a reasonable possibility to minimize this problem.

Never too early for the opportunists!

Primary HIV infection can occur in 40-90% of individuals recently infected with HIV. Variable symptoms usually suggestive of a flu-like illness as well as high-level HIV viraemia and steep decline in CD4 cell count are often noted. We report a case of a previously healthy homosexual man who presented with symptoms suspicious of primary HIV infection as well as non-productive cough associated with chest CT finding of diffuse ground glass appearance in lungs. Recent HIV seroconversion was confirmed. Diagnosis of Pneumocystis jirovecii pneumonia was made on transbronchial lung biopsy. The symptoms improved rapidly after initiation of treatment with trimethoprim-sulfamethoxazole. It is important to recognise that although Pneumocystis pneumonia is generally seen in the setting of AIDS, it can occasionally also occur during primary HIV infection.

Performances of four fourth-generation human immunodeficiency virus-1 screening assays

Fourth-generation human immunodeficiency virus-1 (HIV-1) screening assays have improved sensitivity, but vary in performance characteristics. The purpose of this study was to evaluate four different fourth-generation HIV-1 assays. These assays included the AxSYM HIV Ag/Ab Combo (Abbott diagnostics, Delkenheim, Germany), ARCHITECT HIV Ag/Ab Combo (Abbott), Elecsys 2010 HIV Combi (Roche Diagnostics GmbH, Mannheim, Germany), and Elecsys HIV Combi PT (Roche). A total of 1,306 samples that included 1,225 clinical samples and 81 samples consisting of seroconversion panels, an HIV-1 p24 antigen sensitivity panel, and dilution series of HIV-1 lysates and HIV-1 antibodies were tested. All of the assays had sensitivities of 100% on clinical samples. The specificities of the AxSYM, ARCHITECT, Elecsys 2010 HIV Combi, and Elecsys HIV Combi PT were 99.6, 99.6, 99.0, and 99.5%, respectively. Of the 81 samples with different levels of HIV antigen or antibody and/or subtypes, Elecsys HIV Combi PT and ARCHITECT HIV Ag/Ab Combo showed better analytical sensitivities than the other two assays. In summary, the performance characteristics of AxSYM, ARCHITECT, and Elecsys HIV Combi PT were comparable and satisfactory for clinical samples. ARCHITECT HIV Ag/Ab Combo and Elecsys HIV Combi PT have the higher analytical sensitivities, and would be preferable for reducing the window period.

Leveraging a rapid, round-the-clock HIV testing system to screen for acute HIV infection in a large urban public medical center

OBJECTIVE

To describe the prevalence and location of new and acute HIV diagnoses in a large urban medical center. Secondary objectives were to evaluate rapid HIV test performance, the added yield of acute HIV screening, and linkage-to-care outcomes.

DESIGN

Cross-sectional study from November 1, 2008, to April 30, 2009.

METHODS

The hospital laboratory performed round-the-clock rapid HIV antibody testing on venipuncture specimens from patients undergoing HIV testing in hospital and community clinics, inpatient settings, and the emergency department (ED). For patients with negative results, a public health laboratory conducted pooled HIV RNA testing for acute HIV infection. The laboratories communicated positive results from the hospital campus to a linkage team. Linkage was defined as 1 outpatient HIV-related visit.

RESULTS

Among 7927 patients, 8550 rapid tests resulted in 137 cases of HIV infection [1.7%, 95% confidence interval (CI): 1.5% to 2.0%], of whom 46 were new HIV diagnoses (0.58%, 95% CI: 0.43% to 0.77%). Pooled HIV RNA testing of 6704 specimens (78.4%) resulted in 3 cases of acute HIV infection (0.05%, 95% CI: 0.01% to 0.14%) and increased HIV case detection by 3.5%. Half of new HIV diagnoses and two thirds of acute infections were detected in the ED and urgent care clinic. Rapid test sensitivity was 98.9% (95% CI: 93.8% to 99.8%) and the specificity 99.9% (95% CI: 99.7% to 99.9%). More than 95% of newly diagnosed and out-of-care HIV-infected patients were linked to care.

CONCLUSIONS

Patients undergoing HIV testing in EDs and urgent care clinics may benefit from being simultaneously screened for acute HIV infection.

Use of quality rapid diagnostic testing for safe blood transfusion in resource-limited settings

Blood safety in sub-Saharan Africa is jeopardized by multiple and diverse factors, including the predominance of high-risk family/replacement donors and the high prevalence of transfusion-transmissible infections (TTIs). Thus, stringent diagnostic strategies are vital. Western blotting is costly and technically demanding, and nucleic acid testing technologies, which have been reported to reliably reduce the rate of TTI, are not available in resource-limited settings. Therefore, there is a need for reliable and affordable testing alternatives in these settings. Rapid diagnostic testing has been widely adopted in developing countries, but, for effectiveness in blood safety, highly sensitive tests and the strict selection of low-risk blood donors are indispensable. Although the pre-serological window period remains a source of residual risk for transmission of TTIs during blood transfusion, the combination antigen-antibody rapid tests could contribute significantly to shortening the window period. Thus, despite its limitations, rapid diagnostic testing continues to contribute significantly to blood safety, as a cost-effective means of enhancing screening for TTIs and reducing their transmission in resource-limited rural settings.

Comparative performance of electrochemiluminescence immunoassay and EIA for HIV screening in a multiethnic region of China

Background

The recent approval of 4th generation HIV tests has forced many laboratories to decide whether to shift from 3rd to these tests. There are limited published studies on the comparative evaluation of these two different assays. We compare the performance of fourth-generation electrochemiluminescence immunoassay (ChIA) and third-generation enzyme linked immunosorbent assay (EIA) for human immunodeficiency virus (HIV) screening and gauge whether the shift from EIA to ChIA could be better in a multiethnic region of China.

Methodology/Principal Findings

We identified a large number of routine specimens (345,492) using two different assays from Jan 2008 to Aug 2011 in a teaching hospital with high sample throughput. Of the 344,596 specimens with interpretable HIV test results, 526(0.23%) of 228,761 using EIA and 303(0.26%) of 115,835 using ChIA were HIV-1 positive. The false-positive rate of EIA was lower than that of ChIA [0.03% vs. 0.08%, odds ratio 0.33 (95% confidence interval 0.24, 0.45)]. The positive predictive value (PPV) of EIA (89.6%) was significantly higher than that of ChIA (76.1%) (<0.001), reflecting the difference between the two assays. The clinical sensitivities of two assays in this study were 99.64% for EIA and 99.88% for ChIA.

Conclusion

Caution is needed before shifting from 3rd to 4th generation HIV tests. Since none of these tests are perfect, different geographic and ethnic area probably require different considerations with regard to HIV testing methods, taking into account the local conditions.

Real-life evaluation of a human immunodeficiency virus screening algorithm using a single combined p24 antigen-antibody assay

Since May 2010, human immunodeficiency virus (HIV) screening in France has been performed using a single combined fourth-generation assay. One of our major concerns is to verify that this screening strategy is able to diagnose HIV primary infection as soon as possible. Thus, the sensitivity and specificity of this strategy were evaluated on 49,623 serum samples, including 29 primary infections, received for routine HIV testing between September 2010 and November 2011. Specimens were screened using the Enzygnost HIV Integral II enzyme-linked immunosorbent assay (ELISA) kit. All positive sera, according to the manufacturer's recommendations [signal-to-cutoff ratio (S/CO) ≥  1] were retested using the Architect HIV Ag/Ab Combo. Moreover, we defined a grey zone (0.5 < S/CO < 1) and sera within this grey zone were retested using the VIDAS HIV DUO Ultra test and HIV-1 RNA was checked by the Abbott RealTime PCR kit. Screening tests were positive for all primary infections. All samples within the grey zone proved VIDAS HIV DUO Ultra and HIV-1 RNA negative. Overall, the ELISA test sensitivity and specificity were 100 and 99.79 %, respectively. The false-positive rate was higher when S/CO was in the low range (1 to 5). Adding a second screening test for positive sera reduced the false-positive rate from 0.20 to 0.02 %. HIV screening with a single combined assay did not miss any documented primary infection during this evaluation period, even without extending the positivity zone.

Diagnosing acute HIV infection

Individuals with acute HIV infection (AHI) pose a greater transmission risk than most chronically HIV-infected patients and prevention efforts targeting these individuals are important for reducing the spread of HIV infection. Rapid and accurate diagnosis of AHI is crucial. Since symptoms of AHI are nonspecific, its diagnosis requires a high index of suspicion and appropriate HIV laboratory tests. However, even 30 years after the start of the HIV epidemic, laboratory tools remain imperfect and only a few individuals with AHI are identified. We review the clinical presentation of the acute retroviral syndrome, the laboratory markers and their detection methods, and propose an algorithm for the laboratory diagnosis of AHI.

Testing for acute HIV infection: implications for treatment as prevention

PURPOSE OF REVIEW

The aim of this study is to give an overview of the recent literature related to HIV testing with an emphasis on detecting acute HIV infection. Testing technology as well as implications for treatment as prevention will be discussed.

RECENT FINDINGS

HIV testing technology continues to evolve. Advances include updated immunologic formats that detect both HIV antibody and antigen (4th generation assays), new nucleic acid amplification tests, and continued development of rapid assays that can be used in either clinical or nonclinical settings. Because of these advances there are proposed changes for HIV diagnostic algorithms to encourage detection of acute infection. These technologic advances have implications for HIV prevention as testing is a cornerstone for all HIV prevention strategies. There is considerable new research indicating that treatment may be an important aspect of HIV prevention. Data also suggest that detection of acute infection will be important for the success of these prevention strategies.

SUMMARY

Continued improvements in technology and testing practice are vital for the success of HIV prevention. Detection of acute or early HIV infection will likely play a key role in the success of treatment as prevention, as well as play an important role in ongoing behavioral prevention strategies.

HIV testing: the cornerstone of HIV prevention efforts in the USA

An estimated 1.2 million persons in the USA are infected with HIV, of whom approximately 20% are unaware they are infected. HIV testing and knowledge of HIV serostatus have important individual and public health benefits, including reduction of morbidity, mortality and HIV transmission. Although testing is the necessary first step to prevention, more than half of the US adult population has never been tested for HIV. However, this proportion is increasing due to revised national recommendations to make HIV testing a routine part of healthcare, expansion of testing efforts at local, state and national levels, and progress in the development and adoption of new testing technologies. In this article, we describe the essential role of HIV testing as a public health prevention strategy, examine recent advances in HIV testing technologies and testing implementation, and identify future directions for HIV testing in the USA.

Prospective study of the ARCHITECTHIV Ag/Ab Combo fourth generation assay to detect HIV infection in sexually transmitted infection clinics

This prospective, cross-sectional study of HIV testing at two sexually transmitted infection clinics compares testing results from the ARCHITECT HIV Ag/Ab Combo fourth generation assay against the current standard of care in North Carolina (third generation enzyme immunoassay testing with western blot confirmation and reflex nucleic acid amplification testing of pooled seronegative samples). In this setting, the assay reported a sensitivity of 100%, a specificity of 99.9%, and a median turn-around time of 26.1 h.

Genomic detection of human immunodeficiency virus (HIV) by nucleic acid amplification test in a frequent platelet donor during the pre-seroconversion period

Since serological donor-screening tests for HIV were introduced in 1985, the safety of donated blood components has improved dramatically. However, these tests do not completely prevent the risk of transfusion-associated HIV infection related to the use of blood donated during the pre-seroconversion window period. Testing based on nucleic acid amplification is being implemented to screen for HIV-infected blood donated during this period, which has reduced the probability of transmitting HIV through transfusion by shortening the window period. This article describes a case of acute HIV-1 infection, detected using a nucleic acid amplification test (NAT) in a repeat blood donor who donated during the pre-seroconversion window period and whose antigen and anti-HIV antibody expression was observed after molecular marker detection. In addition, the possible route of infection is discussed based on the patient's history, and finally, the need for NAT technology for blood donor screening is emphasized.

Vaccine-induced HIV seropositivity: a problem on the rise

BACKGROUND

Vaccine-induced antibodies to envelope proteins frequently cause HIV seroconversion in uninfected recipients of HIV vaccine candidates and may thus have an impact on the vaccinee's ability to donate blood or acquire a life insurance policy.

OBJECTIVE

To determine the occurrence of positive test results when commonly used HIV immunoassays are used to screen sera of HIV-uninfected volunteers who received an adjuvanted HIV-1 vaccine candidate containing HIV-1 antigens p24, reverse transcriptase, Nef and p17.

STUDY DESIGN

Sera of 50 subjects who received this polyprotein vaccine in a single center in Belgium were tested with 6 HIV screening assays and 1 confirmation test. All samples were drawn one year after the administration of the first of two vaccine doses given with one month interval.

RESULTS

Forty-five (90%) sera showed a positive test result in at least one of the 7 HIV tests used. The positivity rates were 88% in the Elecsys HIV Combi assay, 74% in the ADVIA Centaur EHIV and 48% in the PRISM HIV O Plus assay.

CONCLUSIONS

Interpretation of HIV test results is becoming increasingly complex with the growing number of volunteers participating in prophylactic HIV vaccine trials worldwide and the rising number of viral antigens included in these vaccine candidates. The results of this study in recipients of a highly immunogenic adjuvanted polyprotein HIV vaccine candidate devoid of envelope proteins, illustrate the increasing need for approaches that can discriminate HIV infection-induced antibodies from those elicited by a vaccine.

Comparison of HIV-1 detection in plasma specimens and dried blood spots using the Roche COBAS Ampliscreen HIV-1 test in Kisumu, Kenya

The World Health Organization recommends screening donor blood for HIV in centralized laboratories. This recommendation contributes to quality, but presents specimen transport challenges for resource-limited settings which may be relieved by using dried blood spots (DBS). In sub-Saharan Africa, most countries screen donor blood with serologic assays only. Interest in window period reduction has led blood services to consider adding HIV nucleic acid testing (NAT). The U.S. Food and Drug Administration (FDA) mandates that HIV-1 NAT blood screening assays have a 95% detection limit at or below 100 copies/ml and 5000 copies/ml for pooled and individual donations, respectively. The Roche COBAS Ampliscreen HIV-1 test, version 1.5, used for screening whole blood or components for transfusion, has not been tested with DBS. We compared COBAS Ampliscreen HIV-1 RNA detection limits in DBS and plasma. An AIDS Clinical Trials Group, Viral Quality Assurance laboratory HIV-1 standard with a known viral load was used to create paired plasma and DBS standard nine member dilution series. Each was tested in 24 replicates with the COBAS Ampliscreen. A probit analysis was conducted to calculate 95% detection limits for plasma and DBS, which were 23.8 copies/ml (95% CI 15.1-51.0) for plasma and 106.7 copies/ml (95% CI 73.8-207.9) for DBS. The COBAS Ampliscreen detection threshold with DBS suggests acceptability for individual donations, but optimization may be required for pooled specimens.

HIV testing strategies: test performance is important, but not sufficient

Minimum accuracy of HIV diagnostic tests is considered the pillar on which testing strategies for all settings must be based. Systematic reviews and meta-analyses have shown that performance of the same test in different settings may vary according to several factors, resulting in different confidence intervals for sensitivity and specificity. Prevalence of HIV infection may influence observed test accuracy. The purpose of this article is to use the knowledge from meta-analyses of general diagnostic tests to inform the specific field of HIV diagnostic strategies. We propose the 'Bayesian' thinking: considering the pretest probability (i.e., prevalence, risk factors) and understanding test limitations to estimate a post-test probability of HIV diagnosis. Cost-effectiveness analysis, patient preferences and ethical issues must also be considered in HIV testing strategies.

Performance characteristics of a combined hepatitis C virus core antigen and anti-hepatitis C virus antibody test in different patient groups

We evaluated the performance of a hepatitis C virus (HCV) antigen/antibody combination test [Murex HCV Antigen/Antibody Combination Test (Murex Ag/Ab test)] by comparing it with the current third-generation HCV antibody enzyme immunoassay (anti-HCV). A total of 403 serum samples were consecutively collected from four patient groups: healthy controls (n=100); HCV-infected patients (HCV group, n=102); Human immunodeficiency virus (HIV)/HCV-infected patients (HIV/HCV group, n=100); and patients with uremia (uremia group, n=101). Performances were evaluated for the Murex Ag/Ab, anti-HCV, and HCV RNA in the HIV/HCV and uremia patient groups. In the HCV group, all 102 samples showed concordant positive and negative results for anti-HCV, Murex Ag/Ab, and HCV RNA tests. In the HIV/HCV group, all 100 samples were positive for both anti-HCV and Murex Ag/Ab tests, whereas 88 patients (88%) were HCV RNA positive. In the uremia group, 14 (69.0%) of the 23 anti-HCV-positive patients were HCV RNA positive, whereas 14 (77.8%) of the 18 Murex Ag/Ab-positive patients were HCV RNA positive. None of anti-HCV-negative or Murex Ag/Ab-negative patients were HCV RNA positive. Based on the HCV RNA assay, the sensitivities for both anti-HCV and Murex Ag/Ab assays were 100%, whereas the specificities of these two assays were 89.7% and 95.4%, respectively. With good sensitivity and specificity, the Murex Ag/Ab assay could be a useful alternative diagnostic tool, especially in immunocompromised populations, such as patients with uremia or those infected with HIV.

Characteristics of blood donors and donated blood in sub-Saharan Francophone Africa

BACKGROUND

The importance of blood safety in public health was recognized long ago, and data are essential to plan strategies to improve the status. This study aims to obtain data on blood donor and blood donation characteristics that would complement blood safety data from national and international organizations.

MATERIALS AND METHODS

A questionnaire was sent to seven Francophone countries (Burkina Faso, Cameroon, Congo, Ivory Coast, Mali, Niger, and Rwanda) and was structured to obtain objective data on blood donors and donated blood and in administrative and technical organization.

RESULTS

The results reflect a poor level of organization of blood transfusion centers in large regions of the African continent, insufficient supply of blood products, high prevalence of transfusion-transmitted infections, limited financial resources, a lack of well-trained personnel, and cultural obstacles. Six countries had less than 50% of their personnel trained in transfusion medicine. Only one country had the entire standard operating procedure written. Female donors represented less than 30% of the donors and the range of percentage of hepatitis B found in donors was 2.76% to 18.96%.

CONCLUSION

The inclusion of these regions in future blood safety surveys and in the development of national blood transfusion programs is essential and will undoubtedly require the assistance of international organizations.