Characterizing hepatitis B virus infection in children in the Democratic Republic of Congo to inform elimination efforts.

Objective: Despite global reductions in hepatitis B virus (HBV) prevalence, an estimated 6.2 million children are infected, two-thirds of whom live in the WHO Africa region. We sought to characterize childhood HBV to inform elimination efforts in the Democratic Republic of Congo (DRC), one of the largest and most populous African countries. Methods: Using the most recent (2013-14) nationally representative Demographic and Health Survey in the DRC, we analyzed HBV surface antigen (HBsAg) on dried blood spots and associated survey data from children aged 6-59 months. We estimated HBsAg-positivity prevalence nationally, regionally, and by potential correlates of infection. We evaluated spatial variation in HBsAg-positivity prevalence, overall and by age, sex, and vaccination status. Findings: Using data from 5,679 children, we found national HBsAg-positivity prevalence was 1.3% (95% CI: 0.9%-1.7%), but ranged from 0.0% in DRC's capital city province, Kinshasa, to 5.6% in northwestern Sud-Ubangi Province. Prevalence among boys (1.8%, 95% CI: 1.2%-2.7%) was double that among girls (0.7%, 95%CI: 0.4%-1.3%). Tetanus antibody-negativity, rurality, and lower household wealth were also significantly associated with higher HBsAg-positivity prevalence. We observed no difference in prevalence by age. Children had higher HBsAg-positivity odds if living with ≥1 HBsAg-positive adult household member (OR: 2.3, 95%CI: 0.7-7.8), particularly an HBsAg-positive mother (OR: 7.2, 95%CI:1.6-32.2). Conclusion: In the largest national survey of HBV among children and household contacts in the DRC, we found that childhood HBV prevalence was 10-60 times the global target of 0.1%. We highlight specific regions and populations for further investigation and focused prevention efforts.

Bioethics education in Democratic Republic of Congo: Experiences and challenges.

In regions marked by socio-economic turmoil, the task of teaching bioethics to health professionals and researchers can be more challenging than elsewhere. To demonstrate this, in this article we describe some of our teaching experiences in the Democratic Republic of Congo over the past decade. A first difficulty is linguistic. Anglo-Saxon language and culture largely dominates the field of bioethics, complicating teaching and education for those who do not master the language. A second obstacle is conceptual. Bioethics is often misunderstood as reflection on technological developments in medicine, which distorts its objectives and narrows its scope, particularly in resource-constrained settings. A third difficulty is cultural and political. Ethics in this setting is difficult to distinguish from common morality and the work of moralists, who comment on problems in medicine from a religious standpoint. Moreover, when interacting with communities and institutions that are strongly hierarchical, the critical stance of bioethics can give rise to resistance and rejection. These are among the array of difficulties that undoubtedly have given rise to sharp critiques of bioethics training initiatives in developing countries, where the introduction of bioethics has been depicted as a form of Western imperialism. While taking these criticisms seriously, our experiences in the field show how these seemingly insurmountable difficulties can be transformed into (more or less) manageable challenges.

Dans les régions marquées par un contexte socioéconomique difficile, les difficultés sont plus nombreuses qu'ailleurs pour ceux qui se donnent pour tâche de former à la réflexion éthique les professionnels de la santé et les chercheurs. Pour le montrer, nous évoquons dans cet article nos expériences en République Démocratique du Congo. Une première difficulté est à chercher du côté linguistique. En effet, la langue et la culture anglo-saxonnes dominent largement la discipline, compliquant la tâche de ceux qui maîtrisent mal l'anglais. Unedeuxième difficulté à surmonter est d'ordre conceptuel. Les objectifs et le champ d'application de la bioéthique sont souvent mal compris, ce qui peut conduire à confondre les spécialistesde la discipline tantôt avec des moralistes surtout préoccupés par le progrès biotechnologique, tantôt avec des référents religieux. La troisième difficulté évoquée est de nature politique et culturelle. Lorsqu'elle entre en interaction avec des communautés très hiérarchisées et conservatrices, la posture critique de la bioéthique peut susciter des réactions de rejet. Ce sont sans doute ces difficultés qui ont alimenté certaines critiques acerbes sur la pertinence des formations à l'éthique dans des zones marquées par les urgences sanitaires et alimentaires ou certaines accusations présentant ces démarches comme un avatar de plus de l'impérialisme occidental. Tout en prenant au sérieux ces difficultés, nous montrons par nos expériences qu'elles peuvent être transformées en défis à relever.

HIV infection and risk factors among the armed forces personnel stationed in Kinshasa, Democratic Republic of Congo.

Despite recent declines in HIV incidence, sub-Saharan Africa remains the most heavily affected region in the global HIV/AIDS epidemic. Estimates of HIV prevalence in African military personnel are scarce and inconsistent. We conducted a serosurvey between June and September 2007 among 4043 Armed Forces personnel of the Democratic Republic of Congo (FARDC) stationed in Kinshasa, Democratic Republic of Congo (DRC) to determine the prevalence of HIV and syphilis infections and describe associated risk behaviours. Participants provided blood for HIV and syphilis testing and responded to a demographic and risk factor questionnaire. The prevalence of HIV was 3.8% and the prevalence of syphilis was 11.9%. Women were more likely than men to be HIV positive, (7.5% vs. 3.6% respectively, aOR: 1.66, 95% C.I: 1.21-2.28, p < 0.05). Factors significantly associated with HIV infection included gender and self-reported genital ulcers in the 12 months before date of enrollment. The prevalence of HIV in the military appears to be higher than the general population in DRC (3.8% vs. 1.3%, respectively), with women at increased risk of infection.

Male partner voluntary counselling and testing associated with the antenatal services in Kinshasa, Democratic Republic of Congo: a randomized controlled trial.

Low male participation in voluntary counselling and testing (VCT) services at antenatal clinics (ANCs) represents a lost HIV-prevention opportunity. A three-arm randomized controlled trial (RCT) was conducted that offered VCT at a neighbourhood health centre, bar or church to the male partners of pregnant women attending a maternity unit in Kinshasa, Democratic Republic of Congo (DRC). The primary outcome was the proportion of male participation at VCT; secondary outcomes were uptake of couple counselling and determinants of male and couple participation. From a total of 2706 women included in the study, 591 male partners (22%) attended one of the three venues. Male participation was significantly higher in bars (26%, P < 0.001), and higher but not statistically significant in church-based VCT (21%, P = 0.163) compared with health centre VCT (18%). Male participation in VCT associated with ANCs was higher in non-health service settings, particularly in bars. A combination of different strategies rather than single targeted interventions will be needed to increase VCT uptake in male partners of women seeking VCT at ANCs.

Genetic diversification and recombination of HIV type 1 group M in Kinshasa, Democratic Republic of Congo.

As the HIV-1 pandemic becomes increasingly complex, the genetic characterization of HIV strains bears important implications for vaccine research. To better understand the molecular evolution of HIV-1 viral diversity, we performed a comparative molecular analysis of HIV strains collected from high-risk persons in Kinshasa, Democratic Republic of Congo (DRC). Analysis of the gag-p24, env-C2V3 and -gp41 regions from 83 specimens collected in 1999-2000 revealed that 44 (53%) had concordant subtypes in the three regions (14 subsubtype A1, 10 subtype G, 8 subtype D, 5 subtype C, 2 each subsubtype F1 and CRF01_AE, and one each of subtypes H and J, and subsubtype A2, while the remaining 39 (47%) had mosaic genomes comprising multiple subtype combinations. Similar multisubtype patterns were also observed in 24 specimens collected in 1985. Sequence analysis of the gag-pol region (2.1 kb) from 21 discordant specimens in the gag-p24, env-C2V3 and -gp41 regions in 1985 and 1999-2000 further confirmed the complex recombinant patterns. Despite the remarkable similarity in overall subtype distribution, the intra- and intersubtype distances of major subtypes A1 and G increased significantly from 1985 to 1999-2000 (p=0.018 and p=0.0016, respectively). Given the complexity of HIV-1 viruses circulating in DRC, efforts should focus on the development of vaccines that result in cross-clade immunity.

Short report: analysis of anti-malaria immune response during human immunodeficiency virus infection in adults in Kinshasa, Democratic Republic of the Congo.

Co-infection of human immunodeficiency virus and malaria is not uncommon in people living in sub-Saharan Africa. Since HIV infection results in immune deficiency, it may alter the ability of HIV patients to mount proper immune responses against malaria parasites. We measured specific malaria antibodies in 47 specimens from 25 couples from Kinshasa, Democratic Republic of the Congo (DRC), according to their HIV status, and investigated probable interaction between malaria and HIV infection. Plasma samples were analyzed for HIV markers (western blot and viral load) and malaria parasite-specific antibody (antibody titer, pattern of antigen recognized by western blotting, and parasite neutralizing antibodies assayed by growth inhibition). No correlation was identified between measured HIV infection status and malaria-specific parameters.

HIV-1-specific cytolytic T-lymphocyte activity correlates with lower viral load, higher CD4 count, and CD8+CD38-DR- phenotype: comparison of statistical methods for measurement.

OBJECTIVES: The objective of this study was to use novel statistical methods to determine the correlation between HIV-1-specific cytolytic T-lymphocyte (CTL) activity and HIV-1 plasma viral load, in a blinded study of HIV-infected patients at various stages of clinical disease. METHODS: Peripheral blood mononuclear cells (PBMC) were collected and stored at enrollment and 2 weeks later, from 15 HIV-infected individuals who were receiving stable antiretroviral therapy for the previous 6 weeks and during the study period. HIV-1-specific CTL activity was measured using an antigen-specific PBMC in vitro stimulation method. Measurements of plasma viral load, as well as CD4+ and CD8+ T lymphocytes expressing T-cell activation markers (DR and CD38) were also performed at each time point. CTL activity was quantified using three separate statistical methods: area under the net HIV-specific lysis curve (AUC), lytic units (LU20), and linear regression (LR) of net HIV-specific lysis. RESULTS: HIV-1 nef-, pol- and gag-specific CTL activity (AUC method) was significantly higher in subjects with a plasma viral load < or = 30,000 RNA copies/ml, than in those with viral load >30,000 RNA copies/ml. When plasma viral load was analyzed as a continuous variable, there was a strong correlation between higher CTL activity and lower viral load for nef (r2 = .77; p < .001), pol (r2 = .63; p < .001) and gag (r2 = 0.75; p < .001) targets by the AUC, but not for the LU20 analysis. Using the LR analysis, which is less dependent on in vitro PBMC growth than the AUC analysis, an independent association was demonstrated between nef- and gag-specific CTL activity and lower viral load. Measurement of CTL activity was also significantly correlated with a higher percentage of circulating CD8+DR-CD38- T lymphocytes. CONCLUSIONS: In this blinded study using an in vitro stimulation of frozen PBMC, higher HIV-1 nef-, pol-, and gag-specific CTL activity correlated with lower plasma viral load, particularly in patients with a CD4 count <500 cells/mm3. Two new statistical methods for estimating CTL activity, AUC and LR analyses, were superior to the standard lytic unit (LU20) method for demonstrating this correlation. These data also demonstrated that higher circulating CD8+ T lymphocytes with a DR-CD38-phenotype, correlate with a lower plasma viral and load and higher HIV-specific CTL activity. This suggests that lymphocytes with this double-negative phenotype may include circulating HIV-specific CD8+ CTL.

Lack of association between anti-V3 loop antibody and perinatal HIV-1 transmission in Kinshasa, Zaire, despite use of assays based on local HIV-1 strains.

Maternal antibodies against the V3 loop principal neutralizing domain (PND) have been reported to protect against perinatal HIV-1 transmission. To study this association in an African city with a long-standing HIV epidemic and no established "consensus sequence" for the V3 loop region of gp120, we determined the DNA sequence for the V3 region of HIV-1 from 13 HIV-1-infected residents of Kinshasa, Zaire, and developed peptide enzyme immunoassays (EIAs) reflecting the V3 loop PND for those HIV-1 strains. Using the most broadly reactive locally derived V3 loop peptide in a limited-antigen EIA, there was no significant difference in the perinatal HIV-1 transmission risk between 64 women with anti-V3 loop antibody (transmission risk, 30%) and 104 women without anti-V3 loop antibody (transmission risk, 25%; p = 0.5); this finding was unchanged after we controlled for maternal AIDS and low birth weight. Although we used assays for V3 loop antibody based on local HIV-1 strains and evaluated a large number of mother-child pairs, we found no evidence that maternal anti-V3 loop PND antibody protects against perinatal HIV-1 transmission.

Accurate detection of maternal antibodies to HIV in newborn whole blood dried on filter paper.

OBJECTIVE: The testing of neonatal blood specimens dried on filter paper for maternal HIV antibodies, using an enzyme immunoassay (EIA) with confirmation of repeatedly reactive specimens by immunoblot (IB), was first described in 1987. It has been used to conduct large, unlinked, anonymous HIV seroprevalence surveys for surveillance of HIV in child-bearing women in several countries. We directly assessed the sensitivity and specificity of this combination of tests to detect maternal HIV antibodies. SETTING: Serum samples obtained from mothers delivering at a major hospital in Kinshasa, Zaire were screened for HIV antibody using the rapid assay HIVCHEK. DESIGN: Plasma from HIVCHEK-positive women and age-matched negative controls were tested by enzyme-linked immunosorbent assay (ELISA); repeatedly reactive specimens were confirmed by Western blot (WB). Two days after delivery, whole blood was obtained from each newborn by heel-stick, dried on filter paper, and tested by EIA. Repeatedly reactive specimens were confirmed by IB. MAIN OUTCOME MEASURE: The serologic status of neonatal filter-paper specimens was compared with that of corresponding maternal plasma. RESULTS: The testing of neonatal filter-paper specimens using EIA, with confirmatory testing of repeatedly reactive specimens using IB, was 100.0% sensitive [of the 192 ELISA-positive and WB-positive maternal plasma specimens, 192 of the corresponding newborn filter-paper specimens were EIA-positive and IB-positive; 95% confidence interval (CI), 98.1-100]. The detection of maternal HIV antibodies was 99.6% specific using this combination of tests (of the 281 ELISA-negative or ELISA-positive but WB-negative maternal plasma samples, 280 of the corresponding newborn filter-paper specimens were EIA-negative or EIA-positive but IB-negative; 95% CI, 98.0-100). CONCLUSIONS: Maternal HIV antibodies can be detected accurately by testing neonatal blood dried on filter paper, using EIA with confirmation of repeatedly reactive specimens by IB. This approach can facilitate the determination of HIV seroprevalence in child-bearing women in countries with neonatal screening programs, or where serum or plasma is difficult to obtain.

PIP: Neonatal blood specimens dried on filter paper have been tested for maternal HIV antibodies in large, unlinked, anonymous HIV seroprevalence surveys toward the surveillance of HIV in child-bearing women in several countries. This study assesses the sensitivity and specificity of this combination of tests. The standard approach involves first testing the sample via an enzyme immunoassay (EIA), then confirming repeatedly reactive specimens through immunoblot (IB). To test this methodology, serum samples were obtained from mothers delivering at a major hospital in Kinshasa, Zaire, and screened with rapid assay HIVCHEK for antibody to HIV. Plasma from HIVCHEK-positive women and age-matched negative controls were then subjected to ELISA, with repeatedly reactive samples confirmed with Western blot. Whole blood was later obtained by heel-stick from each newborn 2 days after delivery, dried on filter paper, and tested by EIA and IB for confirmation. The serologic statuses of neonatal filter-paper specimens were then compared with those of corresponding maternal plasma. 100% sensitivity was achieved by testing neonatal filter-paper specimens with EIA and confirming with IB. The combination of tests also proved 99.6% specific for detecting maternal HIV antibodies; both results are at 95% confidence intervals. These results demonstrate that maternal HIV antibodies can therefore be detected accurately by testing neonatal blood dried on filter paper, using EIA, then confirming repeatedly reactive specimens via IB. This approach may help determine HIV seroprevalence in childbearing women in countries with neonatal screening programs or where serum or plasma is difficult to obtain.

Stability of human immunodeficiency virus type 1 antibodies in whole blood dried on filter paper and stored under various tropical conditions in Kinshasa, Zaire.

The use of whole-blood spots on filter paper for the detection of antibody to human immunodeficiency virus type 1 (HIV-1) was evaluated during a 20-week period under a variety of storage environments simulating the harsh tropical field conditions in Kinshasa, Zaire. During the first 6 weeks of storage, all replicates of high- and low-titer HIV-1-positive reference samples remained positive by enzyme immunoassay and Western blotting (immunoblotting), and all replicates of HIV-1-negative samples remained negative under all storage conditions. However, hot and humid storage conditions for up to 20 weeks caused a progressive decline in enzyme immunoassay optical density ratio values, which was particularly noticeable in samples with a low HIV-1 antibody titer. Harsh tropical operational conditions did not cause any repeatedly false-positive results during the 20-week storage period. The use of gas-impermeable bags with desiccant for the storage of blood spots on filter paper improved the stability of HIV-1 antibody detection over time and is recommended for the storage of whole-blood spots on filter paper in harsh tropical field settings.

Comparison of five commercial enzyme-linked immunosorbent assays and Western immunoblotting for human immunodeficiency virus antibody detection in serum samples from Central Africa.

Detection by five different enzyme-linked immunosorbent assays (ELISAs) of antibody to human immunodeficiency virus (HIV) in sera from three Zairian populations consisting of 1,998 individuals with various risks for HIV infection was evaluated. Sera that were reactive by at least one assay and 10% of the nonreactive serum samples were analyzed by Western blot (immunoblot) by using U.S. Public Health Service interpretation criteria. Sera which were positive by ELISA for detection of antibody to HIV-1 and HIV-2 and negative or indeterminate by HIV-1 Western blot were also analyzed by HIV-2 Western blot. Overall, 443 (22.2%) serum specimens were HIV-1 Western blot positive, 390 (19.5%) had indeterminate HIV-1 Western blot patterns, and no samples were HIV-2 Western blot positive. The sensitivity of the ELISAs ranged from 97.5 to 99.8%, and the specificity ranged from 51.7 to 98.4%. By population group, the negative predictive value ranged from 97.1 to 100%, in contrast to the positive predictive value, which varied from 6.6 to 100%. Follow-up results for sera which were indeterminate for antibody to HIV-1 documented only four seroconversions (6.0%) among 67 individuals at high risk for HIV-1 infection and no seroconversions among 202 individuals at relatively low risk for HIV-1 infection. This study demonstrates the importance of evaluating commercial ELISAs with sera from appropriate geographical regions in order to select the most cost-effective and practical assay for use in that region. Furthermore, the high frequency of indeterminate Western blots for African sera emphasizes the continual need for improved confirmatory assays and interpretation criteria.

Heterosexual transmission of HIV-1 among employees and their spouses at two large businesses in Zaire.

To better understand the reasons why up to 80% of all HIV-1 infections in Zaire, but less than 5% in North America and Europe, are acquired through heterosexual transmission, and to assess the impact of HIV-1 infection on a large urban African workforce, we enrolled 7068 male employees, 416 female employees and 4548 female spouses of employees at two large Kinshasa businesses (a textile factory and a commercial bank) in a prospective study of HIV-1 infection. The HIV-1 seroprevalence rate was higher in male employees (5.8%) and their spouses (5.7%) at the bank than among male employees (2.8%) and their spouses (3.3%) at the textile factory. At both businesses HIV-1 seroprevalence was higher among employees in managerial positions (5.0%) than among workers in lower-level positions (3.0%; P less than 0.0001). In a multivariate analysis of male employees, receipt of a transfusion, a history of genital ulcer disease, working at the bank, urethritis, or being divorced or separated were independently associated with HIV-1 infection. During 1987 and 1988, AIDS was the most common cause of death among recently employed workers, accounting for 20 and 24% of all deaths at the textile factory and the commercial bank, respectively. The HIV-1 seroprevalence rate was higher among female workers (7.7%) than among the spouses of male workers (3.9%; P = 0.001). In multivariate analysis of the wives of workers, having an HIV-1-seropositive spouse, receipt of a blood transfusion, or a history of genital ulcer disease were independently associated with HIV-1 infection.(ABSTRACT TRUNCATED AT 250 WORDS)

Successful use of pooled sera to determine HIV-1 seroprevalence in Zaire with development of cost-efficiency models.

To determine the accuracy and cost efficiency of pooling sera prior to HIV-1 testing, sera from 8,000 Kinshasa factory workers and their spouses were screened individually (2.44% seropositive) and in 800 pools of 10 sera each. There were no false-negative or false-positive pools, resulting in a calculated seroprevalence estimate of 2.42%. Further testing of all sera in positive pools can identify HIV-positive individuals. These applications were modeled to compare the cost-efficiency of pooling with individual testing under different conditions. The results suggest that pooling provides an alternative test format for use in both developing and industrialized countries when the seroprevalence and/or the marginal cost of obtaining a sample are sufficiently low. For our cohort, testing only the pools for seroprevalence estimation resulted in a 78% cost saving compared with individual testing; pooling with subsequent identification of individual seropositives represented a 56% cost reduction.