HIV surveillance combining an assay for identification of very recent infection and phylogenetic analyses on dried spots

HIV transmission network analysis allows identifying unreported risk factors in HIV-positive blood donors in France

OBJECTIVES

As sex between men is a major route of human immunodeficiency virus (HIV) infection in most western countries, restrictive deferral rules for blood donation have largely been implemented regarding men having sex with men (MSM). Here, we sought here to assign unreported HIV risk factors in blood donors (BDs) and reevaluated the MSM-associated fraction of HIV transfusion residual risk (%RR_MSM ).

METHODS

We applied a genetic distance-based approach to infer an HIV transmission network for 384 HIV sequences from French BDs and 1337 HIV sequences from individuals with known risk factors (ANRS PRIMO primary HIV infection cohort). We validated the possibility of assigning a risk factor according to clustering using assortative mixing. Finally, we recalculated the %RR_MSM .

RESULTS

A total of 81 of 284 (28.5%) male and 5 of 100 (5%) female BDs belonged to a cluster; 72 (88.9%) of the 81 male BDs belonged to MSM clusters. After cluster correction, 8 of 67 (11.9%), 4 of 21 (19.0%), and 19 of 88 (21.6%) HIV-positive (HIV+) male BDs with heterosexual, other, or unknown risk factors could be reclassified as MSM, accounting for 10.9% of the total HIV+ male BDs. Overall, 139 of 284 HIV+ male donors (48.9%) could be considered MSM between 2000 and 2016 in France. Between 2005 and 2016, the %RR_MSM increase varied from 0 to 19%, without differing significantly from the %RR_MSM before reclassification.

CONCLUSION

Network inference can be used to complement declaration data on risk factors for HIV infection in BDs. This approach, complementary to behavioral studies, is a valuable tool to evaluate the effect of changes in deferral criteria on BD compliance.

Differential utilization of CD4+ by transmitted/founder and chronic envelope glycoproteins in a MSM HIV-1 subtype B transmission cluster

OBJECTIVE

HIV-1 transmission leads to a genetic bottleneck, with one or a few variants of the donor quasispecies establishing an infection in the new host. We aimed to characterize this bottleneck in more detail, by comparing the properties of HIV envelope glycoproteins from acute and chronic infections within the particular context of a male-to-male transmission cluster.

DESIGN

We compared the genotypic and phenotypic properties of envelope glycoproteins from viral variants derived from five study participants from the same transmission cluster.

METHODS

We used single-genome amplification to generate a collection of full-length env sequences. We then constructed pseudotyped viruses expressing selected Env variants from the quasispecies infecting each study participant and compared their infectivities and sensitivities to various entry inhibitors.

RESULTS

The genotypic analyses confirmed the genetic bottleneck expected after HIV transmission, with a limited number of variants identified in four study participants during acute infection. However, the transmitted sequences harbored no evident common signature and belonged to various genetic lineages. The phenotypic analyses revealed no difference in infectivity, susceptibility to the CCR5 antagonist maraviroc, the fusion inhibitor enfurvitide or type-I interferon between viruses from participants with acute and chronic infections. The key property distinguishing transmitted viruses was a higher resistance to soluble CD4, correlated with greater sensitivity to occupation of the CD4 receptor by the anti-CD4 antibodies LM52 and SK3.

CONCLUSION

These results suggest that envelope glycoproteins from transmitted/founder viruses bind CD4 less efficiently than those of viruses from chronic infections.

Increasing prevalence and local transmission of non-B HIV-1 subtypes in the French Antilles and French Guiana between 1995 and 2018

The Caribbean and South American French Overseas Territories (CSAFOT) are the regions most heavily affected by the Human Immunodeficiency Virus type 1 (HIV-1) epidemic in France. Although dominated by HIV-1 subtype B, the detection of non-B subtypes and the great proportion of HIV-positive persons born abroad demonstrated the potential for local spread of non-B subtype strains in CSAFOT. To reconstruct the epidemiologic dynamics of major non-B subtype clusters spreading in CSAFOT, we conducted phylogenetic and evolutionary analyses of 2,523 HIV-1 pol sequences collected from patients living in Martinique, Guadeloupe, and French Guiana from 1995 to 2018. A large variety of HIV-1 non-B subtype strains (eight subtypes, twelve CRFs, and multiple URFs) have been introduced in CSAFOT and their prevalence significantly increases over time in Martinique and Guadeloupe. We identified twelve major transmission networks of non-B subtypes (CRF02_AG and subtypes A3, C, D, and F1) that probably arose in Guadeloupe, Martinique, French Guiana, and mainland France between the late 1970s and the middle 2000s. Phylogeographic analyses support frequent non-B subtype viral transmissions within CSAFOT as well as transatlantic transmission between CSAFOT and mainland France. Domestic transmission networks of non-B subtype variants in CSAFOT comprise both men having sex with men and heterosexual individuals from different age groups. Different HIV-1 non-B subtype variants were sequentially introduced in CSAFOT between the late 1970s and the middle 2000s and are currently spreading through domestic, regional, and/or transatlantic networks of individuals from different age and risk groups.

Revealing geographical and population heterogeneity in HIV incidence, undiagnosed HIV prevalence and time to diagnosis to improve prevention and care: estimates for France

Introduction

To close gaps in HIV prevention and care, knowledge about locations and populations most affected by HIV is essential. Here, we provide subnational and sub‐population estimates of three key HIV epidemiological indicators, which have been unavailable for most settings.

Methods

We used surveillance data on newly diagnosed HIV cases from 2004 to 2014 and back‐calculation modelling to estimate in France, at national and subnational levels, by exposure group and country of birth: the numbers of new HIV infections, the times to diagnosis, the numbers of undiagnosed HIV infections. The denominators used for rate calculations at national and subnational levels were based on population size (aged 18 to 64) estimates produced by the French National Institute of Statistics and Economic Studies and the latest national surveys on sexual behaviour and drug use.

Results

We estimated that, in 2014, national HIV incidence was 0.17‰ (95% confidence intervals (CI): 0.16 to 0.18) or 6607 (95% CI: 6057 to 7196) adults, undiagnosed HIV prevalence was 0.64‰ (95% CI: 0.57 to 0.70) or 24,197 (95% CI: 22,296 to 25,944) adults and median time to diagnosis over the 2011 to 2014 period was 3.3 years (interquartile range: 1.2 to 5.7). Three mainland regions, including the Paris region, out of the 27 French regions accounted for 56% of the total number of new and undiagnosed infections. Incidence and undiagnosed prevalence rates were 2‐ to 10‐fold higher than the national rates in three overseas regions and in the Paris region (p‐values < 0.001). Rates of incidence and undiagnosed prevalence were higher than the national rates for the following populations (p‐values < 0.001): born‐abroad men who have sex with men (MSM) (respectively, 108‐ and 78‐fold), French‐born MSM (62‐ and 44‐fold), born‐abroad persons who inject drugs (14‐ and 18‐fold), sub‐Saharan African‐born heterosexuals (women 15‐ and 15‐fold, men 11‐ and 13‐fold). Importantly, affected populations varied from one region to another, and in regions apparently less impacted by HIV, some populations could be as impacted as those living in most impacted regions.

Conclusions

In France, some regions and populations have been most impacted by HIV. Subnational and sub‐population estimates of key indicators are not only essential to adapt, design implement and evaluate tailored HIV interventions in France, but also elsewhere where similar heterogeneity is likely to exist.

Sensitivity to Broadly Neutralizing Antibodies of Recently Transmitted HIV-1 Clade CRF02_AG Viruses with a Focus on Evolution over Time

Broadly neutralizing antibodies (bnAbs) are promising agents for prevention and/or treatment of HIV-1 infection. However, the diversity among HIV-1 envelope (Env) glycoproteins impacts bnAb potency and breadth. Neutralization data on the CRF02_AG clade are scarce although it is highly prevalent in West Africa and Europe. We assessed the sensitivity to bnAbs of a panel of 33 early transmitted CRF02_AG viruses over a 15-year period of the French epidemic (1997 to 2012). Env pseudotyped CRF02_AG viruses were best neutralized by the CD4 binding site (CD4bs)-directed bnAbs (VRC01, 3BNC117, NIH45-46^G54W, and N6) and the gp41 membrane-proximal external region (MPER)-directed bnAb 10E8 in terms of both potency and breadth. We observed a higher resistance to bnAbs targeting the V1V2-glycan region (PG9 and PGT145) and the V3-glycan region (PGT121 and 10-1074). Combinations were required to achieve full coverage across this subtype. We observed increased resistance to bnAbs targeting the CD4bs linked to the diversification of CRF02_AG Env over the course of the epidemic, a phenomenon which was previously described for subtypes B and C. These data on the sensitivity to bnAbs of CRF02_AG viruses, including only recently transmitted viruses, will inform future passive immunization studies. Considering the drift of the HIV-1 species toward higher resistance to neutralizing antibodies, it appears necessary to keep updating existing panels for evaluation of future vaccine and passive immunization studies.IMPORTANCE Major progress occurred during the last decade leading to the isolation of human monoclonal antibodies, termed broadly neutralizing antibodies (bnAbs) due to their capacity to neutralize various strains of HIV-1. Several clinical trials are under way in order to evaluate their efficacy in preventive or therapeutic strategies. However, no single bnAb is active against 100% of strains. It is important to gather data on the sensitivity to neutralizing antibodies of all genotypes, especially those more widespread in regions where the prevalence of HIV-1 infection is high. Here, we assembled a large panel of clade CRF02_AG viruses, the most frequent genotype circulating in West Africa and the second most frequent found in several European countries. We evaluated their sensitivities to bnAbs, including those most advanced in clinical trials, and looked for the best combinations. In addition, we observed a trend toward increased resistance to bnAbs over the course of the epidemic.

Staging of recent HIV-1 infection using Geenius rapid confirmatory assay compared to INNO-LIA, New Lav and Blot 2.2 assays

BACKGROUND

Besides confirmation of HIV seropositivity, Western Blot (WB) assays play an important role for identification of recent infection based on incomplete antibody reactivity and lack of p31 band.

OBJECTIVES

We evaluated the capacities of the Geenius™ HIV1/2 Confirmatory Assay (Bio-Rad), a new generation rapid confirmatory assay based on immune-chromatography and automated reading, for staging of HIV-1 infection.

STUDY DESIGN

Sixteen samples collected during early HIV-1 infections (Fiebig stage III-VI) were tested using the Geenius assay, and compared to HIV Blot 2.2 WB assay (MP Diagnostics), New Lav Blot I WB assay (Bio-Rad) and INNO-LIA™ HIV I/II Score Dot Blot assay (Fujirebio). Results obtained with Geenius and INNO LIA in 47 newly diagnosed chronic HIV-1 infections were also compared.

RESULTS

The p24 band was less frequently detected in early HIV-1 infections using the Geenius (3/16) compared to the New Lav (15/16, p<0.0001), INNO-LIA (13/16, p=0.0011), and Blot 2.2 (13/16, p=0.0011). Testing samples collected during chronic infection allowed to confirm that p31 band and complete Gag, Pol, Env profiles were less frequently observed using the Geenius assay compared to the INNO LIA assay (p=0.027 for p31, and p=0.0015 for complete profile).

CONCLUSIONS

The Geenius assay is a simple and rapid test showing a high sensitivity to detect Env bands and to confirm HIV-1 seropositivity during the early phases of infection. However, this test is less suitable for distinguishing between later stages of acute and chronic infections because of a reduced sensitivity to detect the p31 and p24 bands compared to INNO LIA and New Lav assays.

Spatiotemporal dynamics of HIV-1 transmission in France (1999-2014) and impact of targeted prevention strategies

Background

Characterizing HIV-1 transmission networks can be important in understanding the evolutionary patterns and geospatial spread of the epidemic. We reconstructed the broad molecular epidemiology of HIV from individuals with primary HIV-1 infection (PHI) enrolled in France in the ANRS PRIMO C06 cohort over 15 years.

Results

Sociodemographic, geographic, clinical, biological and pol sequence data from 1356 patients were collected between 1999 and 2014. Network analysis was performed to infer genetic relationships, i.e. clusters of transmission, between HIV-1 sequences. Bayesian coalescent-based methods were used to examine the temporal and spatial dynamics of identified clusters from different regions in France. We also evaluated the use of network information to target prevention efforts. Participants were mostly Caucasian (85.9%) and men (86.7%) who reported sex with men (MSM, 71.4%). Overall, 387 individuals (28.5%) were involved in clusters: 156 patients (11.5%) in 78 dyads and 231 participants (17%) in 42 larger clusters (median size: 4, range 3–41). Compared to individuals with single PHI (n = 969), those in clusters were more frequently men (95.9 vs 83%, p < 0.01), MSM (85.8 vs 65.6%, p < 0.01) and infected with CRF02_AG (20.4 vs 13.4%, p < 0.01). Reconstruction of viral migrations across time suggests that Paris area was the major hub of dissemination of both subtype B and CRF02_AG epidemics. By targeting clustering individuals belonging to the identified active transmission network before 2010, 60 of the 143 onward transmissions could have been prevented.

Conclusion

These analyses support the hypothesis of a recent and rapid rise of CRF02_AG within the French HIV-1 epidemic among MSM. Combined with a short turnaround time for sample processing, targeting prevention efforts based on phylogenetic monitoring may be an efficient way to deliver prevention interventions but would require near real time targeted interventions on the identified index cases and their partners.

Electronic supplementary material

The online version of this article (doi:10.1186/s12977-017-0339-4) contains supplementary material, which is available to authorized users.