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Introduction: Transcriptomic analyses from early human immunodeficiency virus (HIV) infection have the potential to reveal how HIV causes widespread and lasting damage to biological functions, especially in the immune system. Previous studies have been limited by difficulties in obtaining early specimens., Methods: A hospital symptom-based screening approach was applied in a rural Mozambican setting to enrol patients with suspected acute HIV infection (Fiebig stage I-IV). Blood samples were collected from all those recruited, so that acute cases and contemporaneously recruited, uninfected controls were included. PBMC were isolated and sequenced using RNA-seq. Sample cellular composition was estimated from gene expression data. Differential gene expression analysis was completed, and correlations were determined between viral load and differential gene expression. Biological implications were examined using Cytoscape, gene set enrichment analysis, and enrichment mapping., Results: Twenty-nine HIV infected subjects one month from presentation and 46 uninfected controls were included in this study. Subjects with acute HIV infection demonstrated profound gene dysregulation, with 6131 (almost 13% of the genome mapped in this study) significantly differentially expressed. Viral load was correlated with 1.6% of dysregulated genes, in particular, highly upregulated genes involved in key cell cycle functions, were correlated with viremia. The most profoundly upregulated biological functions related to cell cycle regulation, in particular, CDCA7 may drive aberrant cell division, promoted by overexpressed E2F family proteins. Also upregulated were DNA repair and replication, microtubule and spindle organization, and immune activation and response. The interferome of acute HIV was characterized by broad activation of interferon-stimulated genes with antiviral functions, most notably IFI27 and OTOF. BCL2 downregulation alongside upregulation of several apoptotic trigger genes and downstream effectors may contribute to cycle arrest and apoptosis. Transmembrane protein 155 (TMEM155) was consistently highly overexpressed during acute infection, with roles hitherto unknown., Discussion: Our study contributes to a better understanding of the mechanisms of early HIV-induced immune damage. These findings have the potential to lead to new earlier interventions that improve outcomes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Parker, Judge, Pastor, Fuente-Soro, Jairoce, Carter, Anderson, Mandomando, Clifford, Naniche and Le Souëf.)

Interferon-γ-inducible protein 10 (IP-10) has been suggested as a marker for targeted viral load (VL) monitoring during antiretroviral treatment (ART). We aimed to determine the kinetics of IP-10 during the initial year of ART, with particular regard to the impact of tuberculosis (TB) co-infection on IP-10 secretion. Longitudinal plasma IP-10 levels were quantified in 112 treatment-naive HIV-positive adults at Ethiopian health centers, through enzyme-linked immunosorbent assay (ELISA) using samples obtained before and during the initial 12 months of ART. All participants underwent bacteriological TB investigation before starting ART. In virological responders (VRs; defined as VL < 150 copies/ml with no subsequent VL ≥ 1,000 copies/ml), IP-10 kinetics were analyzed using linear regression models. Among 91/112 (81.3%) participants classified as VRs, 17 (18.7%) had concomitant TB. Median baseline IP-10 was 650 pg/ml (interquartile range [IQR], 428-1,002) in VRs. IP-10 decline was more rapid during the first month of ART (median 306 pg/ml/month) compared with later time intervals (median 7-48 pg/ml/month, P  < 0.001 in each comparison). Although VRs with TB had higher IP-10 levels at baseline (median 1106 pg/ml [IQR, 627-1,704]), compared with individuals without TB (median 628 pg/ml [IQR, 391-885]; P  = 0.003), the rate of IP-10 decline during ART was similar, regardless of TB-status. During the initial year of ART, IP-10 kinetics followed a biphasic pattern in VRs, with a more rapid decline in the first month of ART compared with later time intervals. Baseline IP-10 was higher in individuals with TB versus individuals without TB, but the kinetics during ART were similar. IMPORTANCE To reach the goal of elimination of HIV as public health threat, access to antiretroviral treatment (ART) has to be further scaled up. To ensure viral suppression in individuals receiving ART, novel and robust systems for treatment monitoring are required. Targeting viral load monitoring to identify individuals at increased likelihood of treatment failure, using screening tools, could be an effective use of limited resources for viral load testing. Interferon-γ-inducible protein 10 (IP-10), a host inflammation mediator, has shown potential for this purpose. Here, we have investigated IP-10 kinetics in Ethiopian adults with HIV during the initial year after ART initiation. IP-10 levels decreased in parallel with viral load during ART, and prevalent tuberculosis at ART initiation did not influence IP-10 kinetics. This study shows satisfactory performance for IP-10 as a surrogate marker for viral load in persons starting ART, with no influence of concomitant tuberculosis.

Introduction: The World Health Organization recommends differentiated service delivery (DSD) to support resource-limited health systems in providing patient-centered HIV care. DSD offers alternative care models to clinic-based care for people living with HIV who are stable on antiretroviral therapy (ART). Despite good patient-related outcomes, there is limited evidence of their sustainability. Our review evaluated the reporting of sustainability indicators of DSD interventions conducted in sub-Saharan Africa (SSA)., Methods: We searched PubMed and EMBASE for studies conducted between 2000 and 2019 assessing DSD interventions targeting HIV-positive individuals who are established in ART in sub-Saharan Africa. We evaluated them through a comprehensive sustainability framework of constructs categorized into 6 domains (intervention design, process, external environment, resources, organizational setting, and people involvement). We scored each construct 1, 2, or 3 for no, partial, or sufficient level of evidence, respectively. Interventions with a calculated sustainability score (overall and domain-specific) of >90% or domain-specific median score >2.7 were considered likely to be sustainable., Results: Overall scores ranged from 69% to 98%. Top scoring intervention types included adherence clubs (98%) and community ART groups (95%) which comprised more than half of interventions. The highest scoring domains were design (2.9) and organizational setting (2.8). The domains of resources (2.4) and people involvement (2.3) scored lowest revealing potential areas for improvement to support DSD sustainability., Conclusions: With the right investment in stakeholder involvement and domestic funding, DSD models generally show potential for sustainability. Our results could guide informed decisions on which DSD intervention is likely to be sustainable per setting and highlight areas that could motivate further research., Competing Interests: The authors have no funding or conflicts of interest to disclose., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc.)

Primary HIV infection (PHI) and subsequent chronic infection alter B-cell compartment. However, longitudinal analysis defining the dynamics of B-cell alterations are still limited. We longitudinally studied B-cell subsets in individuals followed for 1 year after PHI (n = 40). Treated and untreated chronic HIV infected (n = 56) and HIV-uninfected individuals (n = 58) were recruited as reference groups at the Manhiça District in Mozambique. B cells were analyzed by multicolor flow-cytometry. Anti-HIV humoral response and plasma cytokines were assessed by ELISA or Luminex-based technology. A generalized activation of B cells induced by HIV occurs early after infection and is characterized by increases in Activated and Tissue-like memory cells, decreases in IgM-IgD- (switched) and IgM-only B cells. These alterations remain mostly stable until chronic infection and are reverted in part by ART. In contrast, other parameters followed particular dynamics: PD-1 expression in memory cells decreases progressively during the first year of infection, Transitional B cells expand at month 3-4 after infection, and Marginal zone-like B cells show a late depletion. Plasmablasts expand 2 months after infection linked to plasma viral load and anti-p24 IgG3 responses. Most of well-defined changes induced by HIV in B-cell activation and memory subsets are readily observed after PHI, lasting until ART initiation. However, subsequent changes occur after sustained viral infection. These data indicate that HIV infection impacts B cells in several waves over time, and highlight that early treatment would result in beneficial effects on the B-cell compartment., Competing Interests: Unrelated to this work, JB is CEO and founder of AlbaJuna Therapeutics, S.L. and JC is CSO and founder of AlbaJuna Therapeutics, S.L. The remaining authors declare that the research was conducted in the absence of any direct commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Jiménez, Pastor, Urrea, Rodríguez de la Concepción, Parker, Fuente-Soro, Jairoce, Mandomando, Carrillo, Naniche and Blanco.)

Background: Implementation of ultrasensitive HIV drug resistance tests for routine clinical use is hampered by uncertainty about the clinical relevance of drug-resistant minority variants. We assessed different detection thresholds for pretreatment drug resistance to predict an increased risk of virological failure., Methods: We did a case-control study nested within a prospective multicountry cohort. Our study included patients from 12 clinical sites in Kenya, Nigeria, South Africa, Uganda, and Zambia. We defined cases as patients with virological failure (ie, those who had either viral load ≥400 copies per mL at 12 months or had switched to second-line antiretroviral therapy [ART] as a result of virological failure before 12 months) and controls as those with viral suppression (viral load <400 copies per mL at 12 months) on first-line non-nucleoside reverse transcriptase inhibitor-based antiretroviral therapy. We assessed pretreatment drug resistance with Illumina MiSeq next-generation sequencing, using the International Antiviral Society (IAS)-USA mutation list or the Stanford HIV Drug Resistance Database (HIVDB) genotypic sensitivity score. We calculated diagnostic accuracy measures and assessed the odds of virological failure using conditional logistic regression for 1%, 5%, and 10% pretreatment drug resistance detection thresholds, compared with the conventional 20% or more used in Sanger-based sequencing., Findings: Paired viral load results before ART and at month 12 of follow-up were available from 1896 participants. We identified 178 patients with virological failure and selected 338 matched controls. We excluded 117 patients from pretreatment drug resistance analysis; therefore, 152 cases of virological failure and 247 controls were included in the final analysis. With the IAS-USA mutation list, at a detection threshold of 20% or more in patients with pretreatment drug resistance, the adjusted odds ratio (OR) for virological failure was 9·2 (95% CI 4·2-20·1) compared with those without pretreatment drug resistance. Lowering the threshold resulted in adjusted ORs of virological failure of 6·8 (95% CI 3·3-13·9) at the 10% threshold, 7·6 (3·4-17·1) at the 5% threshold, and 4·5 (2·0-10·2) at the 1% threshold. Lowering the detection threshold from 20% improved the sensitivity (ie, ability to identify cases) from 12% (n=18) to 13% (n=19) at detection threshold 10%, to 15% (n=23) at detection threshold 5%, and to 17% (n=26) at detection threshold 1%, but caused a slight reduction in specificity (ie, ability to identify controls) from 98% (n=241) to 96% (n=238) at the 10% threshold, 96% (n=236) at the 5% threshold, and a larger reduction to 92% (n=227) at the 1% threshold. Diagnostic ORs were 5·4 (95% CI 2·1-13·9) at the 20% threshold, 3·8 (1·7-8·6) at the 10% threshold, 3·8 (1·8-8·1) at the 5% threshold, and 2·3 (1·2-4·2) at the 1% threshold. Use of the Stanford HIVDB genotypic sensitivity scores yielded similar ORs for virological failure, sensitivities, specificities, and diagnostic ORs., Interpretation: Ultrasensitive resistance testing for pretreatment drug resistance improved identification of people at risk of virological failure; however, this came with a reduction in our ability to identify people with viral suppression, especially at very low thresholds. Further modelling is needed to estimate the optimal trade-off for the 5% and 20% thresholds, balancing improved case finding against unnecessary regimen switching., Funding: The Netherlands Ministry of Foreign Affairs, IrsiCaixa, and European Union., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Accurate HIV-1 incidence estimation is critical to the success of HIV-1 prevention strategies. Current assays are limited by high false recent rates (FRRs) in certain populations and a short mean duration of recent infection (MDRI). Dynamic early HIV-1 antibody response kinetics were harnessed to identify biomarkers for improved incidence assays. We conducted retrospective analyses on circulating antibodies from known recent and longstanding infections and evaluated binding and avidity measurements of Env and non-Env antigens and multiple antibody forms (i.e., IgG, IgA, IgG3, IgG4, dIgA, and IgM) in a diverse panel of 164 HIV-1-infected participants (clades A, B, C). Discriminant function analysis identified an optimal set of measurements that were subsequently evaluated in a 324-specimen blinded biomarker validation panel. These biomarkers included clade C gp140 IgG3, transmitted/founder clade C gp140 IgG4 avidity, clade B gp140 IgG4 avidity, and gp41 immunodominant region IgG avidity. MDRI was estimated at 215 day or alternatively, 267 days. FRRs in untreated and treated subjects were 5.0% and 3.6%, respectively. Thus, computational analysis of dynamic HIV-1 antibody isotype and antigen interactions during infection enabled design of a promising HIV-1 recency assay for improved cross-sectional incidence estimation.

Background: During acute HIV infection, HIV actively replicates but seroconversion has not yet occurred. Primary HIV infection (PHI) is characterized by a transient nonspecific febrile illness, a massive inflammatory response, and the progressive appearance of anti-HIV-specific antibodies. In this study, we have identified patterns of inflammatory biomarkers associated with the innate immunological reaction before completion of a full humoral response., Methods: A symptom-based screening was used to identify acute HIV infection in the Manhiça District Hospital in Mozambique. Plasma levels of biomarkers were determined by Luminex and enzyme-linked immunosorbent assay. Anti-HIV antibodies were analyzed by flow cytometry and Western blot. Statistical analyses used random forest and logistic regression models., Results: Of 3116 rapid test seronegative or indeterminate individuals, 85 (2.7%) had positive plasma HIV viral load and were enrolled as PHI, of which n = 45 (52.9%), n = 8 (9.4%), n = 12 (14.1%), and n = 20 (23.5%) were classified as Fiebig I-III, IV, V, and VI stages, respectively, by Western blot. Comparison of individuals at early (Fiebig I-IV) and late (Fiebig V-VI) immune stages identified significant differences in the expression level of plasma B-cell activating factor , monocyte chemotactic protein-1, sCD163, and monokine induced by interferon (IFN-γ). This cytokine signature classified patients in the preseroconversion phase with a sensitivity of 92.5% and a specificity of 81.2% CONCLUSIONS:: Identification of a cytokine signature specific for the preseroconversion stage of PHI may help to understand the earliest HIV pathogenic events and identify new potential targets for immunotherapy aimed at modulating the cytokine response to HIV infection.

Objectives: The objective of this study was to inform public health actions to limit first-line ART failure and HIV drug resistance in Mozambique., Methods: This was a cross-sectional study. HIV-1-infected adults on first-line ART for at least 1 year attending routine visits in the Manhiça District Hospital, in a semi-rural area in southern Mozambique with no HIV-1 RNA monitoring available, were evaluated for clinical, socio-demographic, therapeutic, immunological and virological characteristics. Factors associated with HIV-1 RNA ≥1000 copies/mL and HIV drug resistance were determined using multivariate logistic regression., Results: The study included 334 adults on first-line ART for a median of 3 years, of which 65% (214/332) had suppressed viraemia, 11% (37/332) had low-level viraemia (HIV-1 RNA 150-999 copies/mL) and 24% (81/332) had overt virological failure (HIV-1 RNA ≥1000 copies/mL). HIV drug resistance was detected in 89% of subjects with virological failure, but in none with low-level viraemia. Younger age [OR = 0.97 per additional year (95% CI = 0.94-1.00), P = 0.039], ART initiation at WHO stage III/IV [OR = 2.10 (95% CI = 1.23-3.57), P = 0.003] and low ART adherence [OR = 2.69 (95% CI = 1.39-5.19), P = 0.003] were associated with virological failure. Longer time on ART [OR = 1.55 per additional year (95% CI = 1.00-2.43), P = 0.052] and illiteracy [OR = 0.24 (95% CI = 0.07-0.89), P = 0.033] were associated with HIV drug resistance. Compared with HIV-1 RNA, clinician's judgement of ART failure, based on clinical and immunological outcomes, only achieved 29% sensitivity and misdiagnosed 1 out of every 4.5 subjects., Conclusions: Public health programmes in Mozambique should focus on early HIV diagnosis, early ART initiation and adherence support. Virological monitoring drastically improves the diagnosis of ART failure, enabling a better use of resources., (© The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Background: Monitoring the HIV epidemic in a defined population is critical for planning treatment and preventive strategies. This is especially important in sub-Saharan Africa, which harbours the highest burden of the disease., Objective: To estimate HIV incidence in adults aged 18-47 years old and to investigate spatial variations of HIV prevalence in Manhiça, a semi-rural area of southern Mozambique., Methods: Two cross-sectional community-based surveys were conducted in 2010 and 2012 to determine HIV prevalence. Individual participants were randomly selected from the demographic surveillance system in place in the area and voluntary HIV counselling and testing was offered at the household level. HIV incidence was calculated using prevalence estimates from the two sero-surveys. Each participant's household was geocoded using a global information system. The Spatial Scan Statistics programme was used to identify areas with disproportionate excess in HIV prevalence., Results: A total of 1511 adults were tested. The estimated HIV prevalence in the community was 39.9% in 2010 and 39.7% in 2012. The overall HIV incidence was 3.6 new infections per 100 person-years at risk (PYAR) [95CI 1.56; 7.88], assuming stable epidemic conditions, and tended to be higher in women (4.9/100 PYAR [95CI 1.74; 11.85]) than in men (3.2/PYAR [95CI 1.36; 9.92]). One cluster with significant excess HIV prevalence was identified at the same geographic location in both surveys. This cluster had an HIV prevalence of 79.0% in 2010 and 52.3% in 2012., Conclusions: The findings of these first individually-randomised community-HIV sero-surveys conducted in Mozambique reinforce the need to combine HIV incidence estimates and research on micro geographical infection patterns to guide and consolidate effective prevention strategies.

Acute human immunodeficiency virus (HIV) infection (AHI) refers to the period between viral transmission and development of an adaptive immune response to HIV antigens (seroconversion) usually lasting 6-8 weeks. Rare cases have been described in which HIV-infected patients fail to seroconvert and instead, develop rapid HIV-mediated clinical decline. We report the case of a Mozambican woman with AHI and malaria coinfection who showed atypical seroconversion and experienced rapid deterioration and death within 14 weeks of diagnosis with AHI. Atypical seroconversion may be associated with rapid progression. Fourth generation rapid tests could lead to earlier identification and intervention for this vulnerable subgroup., (© The American Society of Tropical Medicine and Hygiene.)

Background: Identification of recent HIV-infections is important for describing the HIV epidemic and compiling HIV-RNA-setpoint data for future HIV intervention trials. We conducted a study to characterize recent infections, and HIV-RNA-setpoint within the adult population presenting at a voluntary counselling and testing centre (VCT) in southern Mozambique., Methods: All adults attending the Manhiça District-Hospital VCT between April and October 2009 were recruited if they had at least one positive rapid HIV-serology test. Patients were screened for recent HIV-1 infection by BED-CEIA HIV-incidence test. Clinical examination, assessment of HIV-RNA and CD4 cell counts were performed at enrollment, 4 and 10 months., Results: Of the 492 participants included in this study, the prevalence of recent infections as defined by BED-CEIA test, CD4 counts >200 cells/µl and HIV-RNA >400 copies/mL, was 11.58% (57/492; 95% CI 8.89-14.74). Due to heterogeneity in HIV-RNA levels in recently infected patients, individuals were categorized as having "high" HIV-RNA load if their HIV-RNA level was above the median (4.98 log(10) copies/mL) at diagnosis. The "high" HIV-RNA group sustained a significantly higher HIV-viral load at all visits with a median HIV-RNA setpoint of 5.22 log(10) copies/mL (IQR 5.18-5.47) as compared to the median of 4.15 log(10) copies/ml (IQR 3.37-4.43) for the other patients (p = 0.0001)., Conclusion: The low proportion of recent HIV-infections among HIV-seropositive VCT clients suggests that most of this population attends the VCT at later stages of HIV/AIDS. Characterization of HIV-RNA-setpoint may serve to identify recently infected individuals maintaining HIV viral load>5 log10 copies/mL as candidates for antiretroviral treatment as prevention interventions.

The rapidity of HIV-RNA suppression after initiation of combined antiretroviral therapy (cART) may impact immune reconstitution in developing countries, where patients initiate cART at low CD4 T cell counts. One hundred and thirty-five HIV-1 Mozambican adults initiating cART were prospectively followed over 16 months within a larger observational study. Plasma HIV-RNA, CD4 counts, and CD8 T cell activation were monitored at the pre-cART visit and at 4, 10, and 16 months during cART. Of the 89 patients with available HIV-RNA data at pre-cART and 4 and 10 months post-cART, 68% (60/89) suppressed HIV-RNA at 4 months and were defined as "early virological controllers"(EC). Twenty of the 29 remaining patients who did not control HIV-RNA at 4 months did so at 10 months and were classified as "late virological controllers"(LC). Nine (10%) patients did not control HIV-RNA at either time point. Both initiating an EFV-containing cART regimen and having pre-cART tuberculosis were significantly associated with early HIV-RNA suppression if locked into a multivariate model [EFV OR: 13.6 (95% CI 1.7; 108.1) p = 0.014) tuberculosis OR: 11.0 (95% CI 1.4; 87.9) p = 0.024]. EC demonstrated significantly lower median activated CD8 T cells at 4, 10, and 16 months post-cART than did LC. Approximately 63% (12/19) of LC experienced reappearance of detectable HIV-RNA at 6 months postcontrol as compared to 15% (2/60) of EC (p = 0.001). This study suggests that rapid suppression of HIV-RNA may lead to a lower rate of reappearance of HIV-RNA, which could impact CD8 T cell activation levels in patients initiating cART at low CD4 counts.

Background: The impact and relevance of immune reconstitution inflammatory syndrome-associated with Kaposi sarcoma (IRIS-KS) has not been assessed in sub-Saharan African countries, where the bulk of HIV-1 and KS-associated herpesvirus (KSHV) coinfection occurs. Understanding the risk factors for developing IRIS-KS would aid in the identification and in the improvement of clinical management for high-risk patients., Methods: Sixty-nine consecutive HIV-1 and KSHV coinfected Mozambican adults initiating cART were prospectively followed for development of IRIS-KS over 10 months as part of a larger prospective observational study. Plasma HIV RNA, CD4 counts, anti-KSHV lytic antibodies, and plasma KSHV DNA viral load were assessed at the pre-cART visit and at 4 and 10 months after cART initiation. A survival analysis was performed to assess potential risk factors for developing IRIS-KS., Results: During the first 10 months of combined antiretroviral therapy (cART), 8 patients (8/69, 11.6%) experienced IRIS-KS at a median time of 13.8 weeks after cART initiation. Multivariate analysis identified 4 independent IRIS-KS predictors: clinical pretreatment KS [hazard ratio (HR) 91.7], detectable plasma KSHV DNA (HR 24.4), hematocrit <30% (HR 26.5), and plasma HIV-1 RNA viral load (HR 34.6 per log viral load increase). Treatment with either cART alone or with a combination of cART and systemic chemotherapy led to partial or complete clinical response in 62.5% (5/8) of IRIS-KS cases., Conclusions: This study identified 4 independent predictors of IRIS-KS, which may help to develop screening tools aiding in the identification of patients at high risk of IRIS-KS for whom close clinical supervision is warranted.

Objectives: To determine the prevalence of acute HIV infection (AHI) within the HIV-seronegative adult population presenting with reported fever in a district hospital in southern Mozambique and evaluate clinical, immunological and virological parameters of AHI., Design: This is a prospective observational study., Methods: Three hundred and forty-six adults presenting with reported fever at an outpatient ward at the Manhiça District Hospital in Mozambique were screened for AHI by HIV rapid serology testing, followed by HIV-RNA testing in HIV-seronegative individuals. Plasma from HIV-seronegative patients was pooled in the ratio of 1: 5 for HIV-RNA testing. Whole blood was used for Plasmodium falciparum rapid test determination at screening visit. Follow-up visits at day 7, 4 and 10 months included clinical examination, HIV serotesting and assessment of HIV-RNA, CD4 cell counts and percentage of activated CD8 T cells., Results: HIV serotesting revealed that 37.8% (95% confidence interval 32.7-43.2) of the adults had previously undiagnosed established HIV infection. Among the HIV-seronegative patients, 3.3% (95% confidence interval 1.3-6.7) were found to have AHI as demonstrated by positive HIV-1 RNA testing. Median HIV-1 RNA levels at diagnosis of AHI were 6.21 log10 copies/ml (interquartile range 5.92-6.41) and significantly higher than median HIV-RNA load at 4 months. At day 7 after screening, patients showed a median CD4 cell count of 384 cells/microl (interquartile range 239-441) and a median percentage of activated CD8 T cells of 68.4% (interquartile range 59.6-87.8)., Conclusion: Of patients reporting with fever, 3.3% were shown to be potentially due to AHI. High prevalence of AHI in southern African populations may warrant investigation of tools and target populations for AHI screening as a novel way to address HIV prevention.

We assessed the effect of maternal human immunodeficiency virus (HIV) infection on birth outcomes and infant survival in rural Mozambique. Pregnant women attending the antenatal clinic were recruited. These women and their infants were followed-up for one year. Birth outcomes were assessed at delivery and infant HIV status was determined at 1 and 12 months of age. Women positive for HIV were more likely to have anemia at delivery than women negative for HIV (51.3% versus 35.4%; P < 0.001). Infants born to HIV-positive mothers had a significantly higher post-neonatal mortality rate than infants born to HIV-negative mothers (7.8% versus 1.9%; P < 0.001). The rate of transmission of HIV by breastfeeding during the first year of life was 15.1% (95% confidence interval = CI 7.6-22.4). Assessment of the impact of HIV infection on birth outcomes in rural Africa is essential for tailoring public health measures to reduce mother-to-child transmission of HIV and excess infant mortality.

Objectives: Malaria infection may impact on mother-to-child transmission (MTCT) of HIV-1. Prevention of malaria in pregnancy could thus potentially affect MTCT of HIV. We studied the impact of intermittent preventive treatment during pregnancy (IPTp) on HIV-1 MTCT in southern Mozambique., Methods: A total of 207 HIV-positive Mozambican pregnant women were enrolled in the study as part of a randomized placebo-controlled trial of two-dose sulfadoxine-pyrimethamine (SP) IPTp in women receiving single-dose nevirapine to prevent MTCT of HIV. HIV RNA viral load, maternal anaemia and peripheral and placental malaria were assessed at delivery. Infant HIV status was determined by DNA polymerase chain reaction (PCR) at 1 month of age., Results: There were 19 transmissions of HIV in 153 mother-infant pairs. IPTp with SP did not have a significant impact on MTCT (11.8% in the SP group vs. 13.2% in the placebo group; P=0.784) or on maternal HIV RNA viral load [16 312 (interquartile range {IQR} 4076-69 296) HIV-1 RNA copies/mL in the SP group vs. 18 274 (IQR 5471-74 104) copies/mL in the placebo group; P=0.715]. In multivariate analysis, maternal HIV RNA viral load [adjusted odds ratio (AOR) 19.9; 95% confidence interval (CI) 2.3-172; P=0.006] and anaemia (haematocrit <33%; AOR 7.5; 95% CI 1.7-32.4; P=0.007) were independent risk factors for MTCT. Placental malaria was associated with a decrease in MTCT (AOR 0.23; 95% CI 0.06-0.89; P=0.034)., Conclusions: IPTp with SP was not associated with a significant impact on MTCT of HIV. Maternal anaemia was an independent risk factor for MTCT.

In this study, we analyzed the human immunodeficiency type 1 (HIV-1) viruses circulating between 1999 and 2004 in antiretroviral-naive women from a rural area of southern Mozambique. Nucleotide sequencing of the HIV-1 long terminal repeat (LTR) U3, envelope (env) C2V3C3, and protease (pr) genomic regions was performed from women sera samples collected in 1999 and 2004. Phylogenetic analysis revealed that all amplified sequences belonged to subtype C. Although env sequences were predominantly CCR5-tropic (R5), CXCR4-tropic (X4) variants were also identified (13%). Both 1999 and 2004 sequences were widely dispersed across multiple clusters and were related to different reference sequences from neighboring countries. Sequences from 2004 showed significantly more nucleotide genetic diversity than sequences from 1999. Importantly, genetic diversification was also observed at the pr and env amino acid level, suggesting that positive selection forces were implicated in the viral diversification. These results indicate the rapid spread and diversification of subtype C virus in Mozambique where HIV-1 prevalence in the Manhiça antenatal clinic reached 23% in 2004.

We investigated the relative importance of binding site occupancy and epitope specificity in antibody neutralization of human immunodeficiency virus (HIV) type 1 (HIV-1). The neutralization of a T-cell-line-adapted HIV-1 isolate (MN) was analyzed with a number of monovalent recombinant Fab fragments (Fabs) and monoclonal antibodies with a range of specificities covering all confirmed gp120-specific neutralization epitopes. Binding of Fabs to recombinant monomeric gp120 was determined by surface plasmon resonance, and binding of Fabs and whole antibodies to functional oligomeric gp120 was determined by indirect immunofluorescence and flow cytometry on HIV-infected cells. An excellent correlation between neutralization and oligomeric gp120 binding was observed, and a lack of correlation with monomeric gp120 binding was confirmed. A similar degree of correlation was observed between oligomeric gp120 binding and neutralization with a T-cell-line-adapted HIV-1 molecular clone (Hx10). The ratios of oligomer binding/neutralization titer fell, in general, within a relatively narrow range for antibodies to different neutralization epitopes. These results suggest that the occupancy of binding sites on HIV-1 virions is the major factor in determining neutralization, irrespective of epitope specificity. Models to account for these observations are proposed.

The spectrum of the anti-human immunodeficiency virus (HIV) neutralizing immune response has been analyzed by the production and characterization of monoclonal antibodies (mAbs) to the viral envelope glycoproteins, gp41 and gp120. Little is known, however, about the neutralization mechanism of these antibodies. Here we show that the binding of a group of neutralizing mAbs that react with regions of the gp120 molecule associated with and including the V2 and V3 loops, the C4 domain and supporting structures, induce the dissociation of gp120 from gp41 on cells infected with the T cell line-adapted HIV-1 molecular clone Hx10. Similar to soluble receptor-induced dissociation of gp120 from gp41, the antibody-induced dissociation is dose- and time-dependent. By contrast, mAbs binding to discontinuous epitopes overlapping the CD4 binding site do not induce gp120 dissociation, implying that mAb induced conformational changes in gp120 are epitope specific, and that HIV neutralization probably involves several mechanisms.

It has been proposed recently that the cell surface peptidase CD26 acts in concert with CD4, the human immunodeficiency virus (HIV) primary receptor molecule, to mediate HIV entry into permissive cells. We have failed to detect significant levels of CD26 cell surface expression and enzymatic activity in a number of commonly propagated human CD4+ cell lines, although CD26 mRNA was present at very low levels, as detected by reverse transcription PCR. No relationship existed between the expression of CD26 and the ability of these cells to be infected with HIV or to fuse to form syncytia. We have tested two inhibitors of CD26 enzymatic activity and several anti-CD26 monoclonal antibodies and found that they inhibit neither HIV infection nor HIV-induced syncytium formation. NIH 3T3 cells stably transfected with the cDNAs for human CD4 and CD26 expressed these molecules at the cell surface and had CD26 enzymatic activity. Inoculation of the double transfectants with HIV did not result in virus entry above the background level, as verified by PCR amplification of viral DNA. We were unable to recover infectious virus from the HIV-inoculated NIH 3T3 double transfectants either by transfer of supernatants or by cocultivation with human CD4+ indicator cells. Moreover, the transfectants did not fuse with HIV-infected cells to form syncytia, nor were syncytia observed in HIV-inoculated cultures. These results are inconsistent with the CD26 molecule being a cofactor for entry of HIV in CD4+ cells.