HIV-1 superinfection

Genetic Evolution Between HIV-1 Groups M and O: HIV-1/MO Recombinant Forms

HIV exhibits significant genetic diversity, with genetic recombination being a major evolutionary process. The co-circulation of HIV-1/M and HIV-1/O variants has led to the description of 20 HIV-1/M+O dual infections since 1998. Despite the genetic divergence between these variants, HIV-1/M+O dual infections have resulted in the emergence of HIV-1/MO intergroup recombinant forms, with 20 unique HIV-1/MO recombinant forms (URF_MO) currently described, raising the question of a possible benefit of the recombination and the modalities of their emergence. This review summarized the current knowledge of HIV-1/MO recombinant forms, including their virological and genetic characteristics, phylogenetic analysis, genome profiles, and breakpoints number and location. This study also identified the potential impacts of HIV-1/MO recombination on diagnosis, monitoring, and treatment, as well as the replicative capacity of such recombinants. This review highlighted the greater diversity and complexity of HIV-1/MO recombinants than originally thought, offering new research perspectives on their emergence and virological properties.

High HIV diversity, recombination, and superinfection revealed in a large outbreak among persons who inject drugs in Kentucky and Ohio, USA

We investigated transmission dynamics of a large human immunodeficiency virus (HIV) outbreak among persons who inject drugs (PWID) in KY and OH during 2017-20 by using detailed phylogenetic, network, recombination, and cluster dating analyses. Using polymerase (pol) sequences from 193 people associated with the investigation, we document high HIV-1 diversity, including Subtype B (44.6 per cent); numerous circulating recombinant forms (CRFs) including CRF02_AG (2.5 per cent) and CRF02_AG-like (21.8 per cent); and many unique recombinant forms composed of CRFs with major subtypes and sub-subtypes [CRF02_AG/B (24.3 per cent), B/CRF02_AG/B (0.5 per cent), and A6/D/B (6.4 per cent)]. Cluster analysis of sequences using a 1.5 per cent genetic distance identified thirteen clusters, including a seventy-five-member cluster composed of CRF02_AG-like and CRF02_AG/B, an eighteen-member CRF02_AG/B cluster, Subtype B clusters of sizes ranging from two to twenty-three, and a nine-member A6/D and A6/D/B cluster. Recombination and phylogenetic analyses identified CRF02_AG/B variants with ten unique breakpoints likely originating from Subtype B and CRF02_AG-like viruses in the largest clusters. The addition of contact tracing results from OH to the genetic networks identified linkage between persons with Subtype B, CRF02_AG, and CRF02_AG/B sequences in the clusters supporting de novo recombinant generation. Superinfection prevalence was 13.3 per cent (8/60) in persons with multiple specimens and included infection with B and CRF02_AG; B and CRF02_AG/B; or B and A6/D/B. In addition to the presence of multiple, distinct molecular clusters associated with this outbreak, cluster dating inferred transmission associated with the largest molecular cluster occurred as early as 2006, with high transmission rates during 2017-8 in certain other molecular clusters. This outbreak among PWID in KY and OH was likely driven by rapid transmission of multiple HIV-1 variants including de novo viral recombinants from circulating viruses within the community. Our findings documenting the high HIV-1 transmission rate and clustering through partner services and molecular clusters emphasize the importance of leveraging multiple different data sources and analyses, including those from disease intervention specialist investigations, to better understand outbreak dynamics and interrupt HIV spread.

High-Risk Sexual Practices Contribute to HIV-1 Double Infection Among Men Who Have Sex with Men in Madrid

Data on the prevalence of double infection (DI) in HIV individuals are lacking in Spain. To fill this gap, we analyzed the prevalence of DI in a cohort of men who have sex with men (MSM) and examined factors contributing to DI. We selected 81 MSM attending Centro Sanitario Sandoval, a sexually transmitted diseases clinic in Madrid. We obtained by ultra-deep sequencing the proviral sequences in gag and env genes and performed a phylogenetic analysis for the identification of DI. Clinical, behavioral, host, and viral factors were studied for its association with DI. We detected six individuals with DI and one case of superinfection with a global prevalence of 8.6%. The genetic distance among the subtype B viruses in monoinfected individuals (24.4%) was lower than the distance between the two viruses in subtype B DI individuals (29.5%). Individuals with a high number of sexual contacts (>25 partners/year) had an 8.66 times higher risk of DI (p = .017). In this MSM cohort the prevalence of HIV DI was estimated at 8.6%. DI was strongly associated with the number of sexual partners. Because of the pathogenic consequences of HIV DI, this high prevalence should promote public health programs targeted at high-risk population such as MSM for the control of HIV infection and DI. HIV DI should be considered for a better clinical management of these individuals.

Defective HIV-1 envelope gene promotes the evolution of the infectious strain through recombination in vitro

Background

HIV-1 produces defective mutants in the process of reproduction. The significance of the mutants has not been well investigated.

Methods

The plasmids of wild type (HIV-1_NL4–3) and Env-defective (HIV-1_SG3^ΔEnv) HIV-1 were co-transfected into HEK293T cells. The progeny virus was collected to infect MT4 cells. The env gene and near-full-length genome (NFLG) of HIV-1 were amplified and sequenced. The phylogenetic diversity, recombinant patterns and hotspots, and the functionality of HIV-1 Env were determined.

Results

A total of 42 env genes and 8 NFLGs were successfully amplified and sequenced. Five types of recombinant patterns of env were identified and the same recombinant sites were detected in different patterns. The recombination hotspots were found distributing mainly in conservative regions of env. The recombination between genes of HIV-1_NL4–3 and HIV-1_SG3^Δenv increased the variety of viral quasispecies and resulted in progeny viruses with relative lower infectious ability than that of HIV_NL4–3. The defective env genes as well as NFLG could be detected after 20 passages.

Conclusion

The existence of the defective HIV-1 promotes the phylogenetic evolution of the virus, thus increasing the diversity of virus population. The role of defective genes may be converted from junk genes to useful materials and cannot be neglected in the study of HIV-1 reservoir.

Transient and asymptomatic meningitis in human immunodeficiency virus-1 subtype C: a case study of genetic compartmentalization and biomarker dynamics

Human immunodeficiency virus (HIV) genetic compartmentalization is defined as genetic differences in HIV in different tissue compartments or subcompartments that characterize viral quasispecies. This descriptive, longitudinal study assessed the dynamics of inflammation, humoral immune response, blood-brain barrier, blood-cerebrospinal fluid (CSF) barrier, as well as neuronal injury biomarkers in serially obtained CSF and serum samples from an antiretroviral (ARV) therapy-naïve patient with HIV-1 subtype C with CSF HIV genetic compartmentalization that resolved spontaneously without ARV treatment. The first CSF sample showed an increase in white blood cell (WBC) count (382 cells/mm3) and a marked increase in the levels of inflammatory cytokines and chemokines, including tumor necrosis factor (TNF)α, interleukin (IL)-10, IP-10, and regulated on activation, normal T cell expressed and secreted (RANTES), which raise the suspicion of dual infection. Serum sample analysis showed all cytokine levels to be normal, with only IP-10 slightly increased. These results corroborate the hypothesis that the CNS immunologic response in a patient with HIV infection was independent of the systemic immunologic response. The patient also had persistently elevated levels of sCD14, neopterin, and β2M, which were strongly suggestive of persistent CNS immunologic stimulation. This report describes a patient with HIV subtype C who developed a transient episode of asymptomatic HIV meningitis with compartmentalization of HIV in the CSF that resolved independently of ARV therapy. Extensive CSF studies were performed as part of an ongoing longitudinal study, which revealed CNS immune abnormalities. This case presents evidence of HIV-1 subtype C neurotropism and compartmentalization.

Dynamical properties and thresholds of an HIV model with super-infection

Super-infection by multiple HIV-1 subtypes, previously thought restricted to high risk groups, has now been reported in the general heterosexual populations at relatively the same incidence rate as in high risk groups. We present a simple deterministic HIV model with super-infection by two HIV-1 subtypes. Mathematical characteristics including the basic reproductive number $(\mathcal{R}_0)$, invasion threshold $(\mathcal{R}_{21},\mathcal{R}_{12})$ and conditions for asymptotic stability are derived. In the absence of super-infection the model exhibits competitive exclusion, and all equilibria are globally attracting if they exist except for the disease free which is a saddle for $\mathcal{R}_0>1.$ The results show that the subtype with the dominant reproductive number exceeding unity dominates the weaker subtype forcing it to extinction regardless of the size of the reproductive number. On the other end, super-infection may promote subtype co-existence whenever the minimum of the subtype specific reproductive numbers $(\mathcal{R}_1,\mathcal{R}_2)$ and the invasion reproductive numbers $(\mathcal{R}_{12},\mathcal{R}_{21})$ exceed unity. Our results demonstrate that if the partial reproductive numbers $(\mathcal{R}_1~\mbox{and}~\mathcal{R}_2 )$ and the invasion reproductive number for the weaker subtype $(\mathcal{R}_{21})$ satisfy $\mathcal{R}_2<1,~\mathcal{R}_1>1~\mbox{and}~\mathcal{R}_{21}>1,$ then primary infection by subtype $1$ may stay the extinction of subtype $2$ despite its relatively low reproductive fitness. For certain parameter ranges, hysteresis (including backward bifurcation) occurs with possible differences in the asymptotic level of disease prevalence. Super-infection may thus facilitate the continued re-generation of reproductively noncompetent subtypes whose subtype specific reproductive numbers will be less than unity while at the same time allowing for the mutual coexistence and persistence of multiple strains. Persistence and co-existence of multiple strains has detrimental effect on vaccine design and development and administration of ART where one or more of the strains are drug resistant.

Frequency of occurrence of HIV-1 dual infection in a Belgian MSM population

Introduction

HIV-1 dual infection is a condition that results from infection with at least two HIV-1 variants from different sources. The scarceness of information on this condition is partly due to the fact that its detection is technically challenging. Using next-generation sequencing we defined the extent of HIV-1 dual infection in a cohort of men who have sex with men (MSM).

Material & methods

Eighty-six MSM, diagnosed with HIV-1 subtype B infection between 2008 and 2013 were selected for next-generation sequencing of the HIV-1 envelope V3. Sequencing was performed on 2 plasma samples collected with an interval of > 6 months before the initiation of antiretroviral therapy. Maximum likelihood phylogenetic trees were inspected for dual infection, defined as the presence of two or more monophyletic clusters with ≥ 90% bootstrap support and a mean between-cluster genetic distance of ≥ 10%. To confirm dual infection, deep V3 sequencing of intermediate samples was performed as well as clonal sequencing of the HIV-1 protease-reverse transcriptase gene.

Results

Five of the 74 patients (6.8%) for whom deep sequencing was successful, showed clear evidence of dual infection. In 4 of them, the second strain was absent in the first sample but occurred in subsequent samples. This was highly suggestive for superinfection. In 3 patients both virus variants were of subtype B, in 2 patients at least one of the variants was a subtype B/non-B recombinant virus.

Conclusions

Dual infection was confirmed in 6.8% of MSM diagnosed with HIV-1 in Belgium. This prevalence is probably an underestimation, because stringent criteria were used to classify viral variants as originating from a new infection event.

HIV-Positive Kidney Donor Selection for HIV-Positive Transplant Recipients

The risks associated with transplanting HIV-positive kidneys into HIV-positive recipients have not been well studied. Since 2008, 43 kidneys from 25 HIV-positive deceased donors have been transplanted into patients who are HIV positive in Cape Town, South Africa. Among the donors, 19 (76%) died secondary to trauma. The average age for donors was 34 (interquartile range, 19-52) years old. In some donors, only one kidney was used because of a limited number of suitable recipients on the waiting list. Only two donors had been previously exposed to antiretroviral triple therapy. In 23 of the deceased organ donors, the HIV status was not known before the time of death. Initial concerns about transplanting HIV-positive allografts into HIV-positive recipients in this clinic revolved around the possibility of HIV superinfection. However, all recipients remained virally suppressed several years after the transplant. Only one recipient experienced an increased viral load after the transplant, which was related to a period of noncompliance on her medication. After counseling and improved compliance, the viral load decreased and became suppressed again. Herein, we discuss the findings of this study and review the literature available on this crucial topic.

Immunological and virological characteristics of human immunodeficiency virus type 1 superinfection: implications in vaccine design

Superinfection is frequently detected among individuals infected by human immunodeficiency virus type I (HIV-1). Superinfection occurs at similar frequencies at acute and chronic infection stages but less frequently than primary infection. This observation indicates that the immune responses elicited by natural HIV-1 infection may play a role in curb of superinfection; however, these responses are not sufficiently strong to completely prevent superinfection. Thus, a successful HIV-1 vaccine likely needs to induce more potent and broader immune responses than those elicited by primary infection. On the other hand, potent and broad neutralization responses are more often detected after superinfection than during monoinfection. This suggests that broadly neutralizing antibodies are more likely induced by sequential immunization of multiple different immunogens than with only one form of envelope glycoprotein immunogens. Understanding why the protection from superinfection by immunity induced by primary infection is insufficient and if superinfection can lead to cross-reactive immune responses will be highly informative for HIV-1 vaccine design.

The Times, They are a-Changing: HOPE for HIV-to-HIV Organ Transplantation

HIV-infected persons who achieve undetectable viral loads on antiretroviral therapy currently have near-normal lifespans. Liver disease is a major cause of non-AIDS-related deaths, and as a result of longer survival, the prevalence of end-stage renal disease in HIV is increasing. HIV-infected persons undergoing organ transplantation generally achieve comparable patient and graft survival rates compared to their HIV-uninfected counterparts, despite a nearly threefold increased risk of acute rejection. However, the ongoing shortage of suitable organs can limit transplantation as an option, and patients with HIV have higher waitlist mortality than others. One way to solve this problem would be to expand the donor pool to include HIV-infected individuals. The results of a South Africa study involving 27 HIV-to-HIV kidney transplants showed promise, with 3- and 5-year patient and graft survival rates similar to those of their HIV-uninfected counterparts. Similarly, individual cases of HIV-to-HIV liver transplantation from the United Kingdom and Switzerland have also shown good results. In the United States, HIV-to-HIV kidney and liver transplants are currently permitted only under a research protocol. Nevertheless, areas of ambiguity exist, including streamlining organ allocation practices, optimizing HIV-infected donor and recipient selection, managing donor-derived transmission of a resistant HIV strain, determining optimal immunosuppressive and antiretroviral regimens, and elucidating the incidence of rejection in HIV-to-HIV solid organ transplant recipients.

First Canadian Case Report of Kidney Transplantation From an HIV-Positive Donor to an HIV-Positive Recipient

RATIONALE

Kidney transplantation has become standard of care for carefully selected patients living with human immunodeficiency virus (HIV) and end-stage renal disease (ESRD) in the highly active antiretroviral therapy (HAART) era. American and European prospective cohort studies have reported similar patient and graft survival compared with HIV-negative kidney transplant recipients. Despite an increased rate of acute rejection, partially due to drug interactions, HIV immunovirologic parameter generally remains under control during immunosuppression. A few cases of kidney transplantation between HIV-infected patients were done in South Africa and showed favorable results. No cases of kidney transplantation from an HIV-positive donor in Canada have previously been reported.

PRESENTING CONCERNS OF THE PATIENT

A 60-year-old Canadian man with HIV infection presented in 2007 with symptoms compatible with acute renal failure secondary to IgA nephropathy. Chronic kidney disease resulted after the acute episode.

DIAGNOSES

Hemodialysis was started in 2012. The patient was referred for a kidney transplantation evaluation.

INTERVENTIONS

The patient underwent kidney transplantation from an HIV-positive donor in January 2016. The recipient's antiretroviral regimen consisted of abacavir, lamivudine, and dolutegravir. No drug interactions have been reported between these antiretrovirals and the maintenance immunosuppressive regimen used.

OUTCOMES

The outcome at 7 months post transplantation was excellent, with good graft function and adequate control of HIV replication, in the absence of opportunistic infections at a time when immunosuppression is at its highest intensity. No acute rejection was reported. An episode of bacteremic graft pyelonephritis due to Enterococcus faecalis was successfully treated after transplantation.

NOVEL FINDING

With careful selection of patient, kidney transplantation between HIV-infected patients is a viable option. The use of antiretroviral drugs free of interactions simplified the dosing and management of the immunosuppressive drugs.

Transplantation in resource-limited setting: using HIV-positive donors for HIV-positive patients

Abstract. Background: A HIV positive-to-positive program was started in South Africa in 2008. The program was started because dialysis is not freely available to everyone, but severely limited and only available to a selected group of patients. Patients and Methods: Between September 2008 and March 2015, 29 patients were transplanted from HIV-positive brain-dead donors at Groote Schuur Hospital transplant team. Donors were either naïve to anti-retroviral therapy or on first line therapy. The recipients were selected to have undetectable plasma HIV type 1 RNA levels and be on a stable antiretroviral regimen. CD4+ T-cell counts of at least 200/mm³ in last 6 months prior to transplant, with no previous serious opportunistic infections. Results: Survivors in the study were followed for a median of 2.4 years. The rate of patient survival was 84% at 1 year and 74% at 5 years. The corresponding graft survival rate was 93% and 84%. Conclusion: Using HIV-positive donors might resolve some of the problems we are experiencing in getting enough donors for our patients wit ESRD. In the USA the HOPE act was accepted in 2014 and this might now also impact on the use of HIV positive donors elsewhere in the world.

Framing Samuel See: the discursive detritus of the moral panic over the "double epidemic" of methamphetamines and HIV among gay men

After being arrested for violating a restraining order against his husband, on November 24, 2013, Yale professor Samuel See died while in lockup at the Union Avenue Detention Center in New Haven, Connecticut. The death received media attention around the world, with readers arguing online about whether See's death was caused by police misconduct, as his friends and colleagues charged in interviews and during a well-publicised march and protest. When an autopsy revealed that he had died from a methamphetamine-induced heart attack, online commentary changed dramatically, with See's many supporters rhetorically abandoning him and others describing him as a stereotype of the gay meth addict who deserved his fate. In this article, I argue that this shift in the interpretation and meaning of See's death can be traced to the discursive structures left by the moral panic about crystal meth in the United States (1996-2008), which comprised within it a secondary moral panic about crystal meth in the gay community and its connection to the spread of HIV and a possible super-strain (2005-2008).

Two cases of possible transmitted drug-resistant HIV: likely HIV superinfection and unmasking of pre-existing resistance

In the UK, patients undergo HIV viral load and genotype testing before they are prescribed antiretroviral therapy. The genotype test guides clinicians in prescribing antiretroviral therapy with maximum efficacy against the patient's specific viral strain. HIV viral load escape under antiretroviral drug therapy, to which the virus was thought to be genotypically susceptible, is commonly observed in patients with poor adherence. We observed early viral escapes in two-newly diagnosed patients, during antiretroviral treatment, with different sequences compared to their original viral resistance test and who reported excellent adherence to and tolerance of their therapy. HIV superinfection with a new viral strain was identified in a patient with multiple risk factors and co-infections with sexually transmitted infections. The second patient was a case of the emergence of primary resistant virus under drug pressure. Both suppressed their virus promptly after treatment switch.

HIV-positive-to-HIV-positive kidney transplantation

BACKGROUND

The outcome of kidney transplantation in human immunodeficiency virus (HIV)–positive patients who receive organs from HIV-negative donors has been reported to be similar to the outcome in HIV-negative recipients. We report the outcomes at 3 to 5 years in HIV-positive patients who received kidneys from HIV-positive deceased donors.

METHODS

We conducted a prospective, nonrandomized study of kidney transplantation in HIV-infected patients who had a CD4 T-cell count of 200 per cubic millimeter or higher and an undetectable plasma HIV RNA level. All the patients were receiving antiretroviral therapy (ART). The patients received kidneys from deceased donors who tested positive for HIV with the use of fourth-generation enzyme-linked immunosorbent assay at the time of referral. All the donors either had received no ART previously or had received only first-line ART.

RESULTS

From September 2008 through February 2014, a total of 27 HIV-positive patients underwent kidney transplantation. Survivors were followed for a median of 2.4 years. The rate of survival among the patients was 84% at 1 year, 84% at 3 years, and 74% at 5 years. The corresponding rates of graft survival were 93%, 84%, and 84%. (If a patient died with a functioning graft, the calculation was performed as if the graft had survived.) Rejection rates were 8% at 1 year and 22% at 3 years. HIV infection remained well controlled, with undetectable virus in blood after the transplantation.

CONCLUSIONS

Kidney transplantation from an HIV-positive donor appears to be an additional treatment option for HIV-infected patients requiring renal-replacement therapy. (Funded by Sanofi South Africa and the Roche Organ Transplantation Research Foundation.)

HIV prevention counseling intervention delivered during routine clinical care reduces HIV risk behavior in HIV-infected South Africans receiving antiretroviral therapy: the Izindlela Zokuphila/Options for Health randomized trial

CONTEXT

Sustainable interventions are needed to minimize HIV risk behavior among people living with HIV (PLWH) in South Africa on antiretroviral therapy (ART), a significant proportion of whom do not achieve viral suppression.

OBJECTIVE

To determine whether a brief lay counselor delivered intervention implemented during routine care can reduce risky sex among PLWH on ART.

DESIGN

Cluster-randomized 16 HIV clinical care sites in KwaZulu Natal, South Africa, to intervention or standard of care.

SETTING

Publicly funded HIV clinical care sites.

PATIENTS

One thousand eight hundred ninety-one PLWH on ART received the HIV prevention counseling intervention (n = 967) or standard-of-care counseling (n = 924).

INTERVENTION

Lay counselors delivered a brief intervention using motivational interviewing strategies based on the Information-Motivation-Behavioral (IMB) Skills model during routine clinical care.

MAIN OUTCOME MEASURES

Number of sexual events without a condom in the past 4 weeks with partners of any HIV status, and with partners perceived to be HIV negative or HIV-status unknown, assessed at baseline, 6, 12, and 18 months.

RESULTS

Intervention participants reported significantly greater reductions in HIV risk behavior on both primary outcomes, compared with standard-of-care participants. Differences in sexually transmitted infection incidence between arms were not observed.

CONCLUSIONS

Effective behavioral interventions, delivered by lay counselors within the clinical care setting, are consistent with the strategy of linking HIV care and HIV prevention and integrating biomedical and behavioral approaches to stemming the HIV epidemic.

TRIAL REGISTRATION

Not applicable.

HIV-positive-to-HIV-positive kidney transplantation--results at 3 to 5 years

BACKGROUND

The outcome of kidney transplantation in human immunodeficiency virus (HIV)-positive patients who receive organs from HIV-negative donors has been reported to be similar to the outcome in HIV-negative recipients. We report the outcomes at 3 to 5 years in HIV-positive patients who received kidneys from HIV-positive deceased donors.

METHODS

We conducted a prospective, nonrandomized study of kidney transplantation in HIV-infected patients who had a CD4 T-cell count of 200 per cubic millimeter or higher and an undetectable plasma HIV RNA level. All the patients were receiving antiretroviral therapy (ART). The patients received kidneys from deceased donors who tested positive for HIV with the use of fourth-generation enzyme-linked immunosorbent assay at the time of referral. All the donors either had received no ART previously or had received only first-line ART.

RESULTS

From September 2008 through February 2014, a total of 27 HIV-positive patients underwent kidney transplantation. Survivors were followed for a median of 2.4 years. The rate of survival among the patients was 84% at 1 year, 84% at 3 years, and 74% at 5 years. The corresponding rates of graft survival were 93%, 84%, and 84%. (If a patient died with a functioning graft, the calculation was performed as if the graft had survived.) Rejection rates were 8% at 1 year and 22% at 3 years. HIV infection remained well controlled, with undetectable virus in blood after the transplantation.

CONCLUSIONS

Kidney transplantation from an HIV-positive donor appears to be an additional treatment option for HIV-infected patients requiring renal-replacement therapy. (Funded by Sanofi South Africa and the Roche Organ Transplantation Research Foundation.).

Reproductive health decision-making in perinatally HIV-infected adolescents and young adults

With widespread access to antiretroviral therapy in the United States, many perinatally HIV-infected (PHIV+) children are surviving into adolescence and adulthood, becoming sexually active and making decisions about their reproductive health. The literature focusing on the reproductive decisions of individuals behaviorally infected with HIV can serve as a springboard for understanding the decision-making process of PHIV+ youth. Yet, there are many differences that critically distinguish reproductive health and related decision-making of PHIV+ youth. Given the potential public health implications of their reproductive decisions, better understanding of factors influencing the decision-making process is needed to help inform the development of salient treatment and prevention interventions. To begin addressing this understudied area, a "think tank" session, comprised of clinicians, medical providers, and researchers with expertise in the area of adolescent HIV, was held in Bethesda, MD, on September 21, 2011. The focus was to explore what is known about factors that influence the reproductive decision-making of PHIV+ adolescents and young adults, determine what important data are needed in order to develop appropriate intervention for PHIV+ youth having children, and to recommend future directions for the field in terms of designing and carrying out collaborative studies. In this report, we summarize the findings from this meeting. The paper is organized around the key themes that emerged, including utilizing a developmental perspective to create an operational definition of reproductive decision-making, integration of psychosocial services with medical management, and how to design future research studies. Case examples are presented and model program components proposed.

Deciphering the complex distribution of human immunodeficiency virus type 1 subtypes among different cohorts in Northern Tanzania

Background

Increased understanding of the genetic diversity of HIV-1 is challenging but important in the development of an effective vaccine. We aimed to describe the distribution of HIV-1 subtypes in northern Tanzania among women enrolled in studies preparing for HIV-1 prevention trials (hospitality facility-worker cohorts), and among men and women in an open cohort demographic surveillance system (Kisesa cohort).

Methods

The polymerase encompassing partial reverse transcriptase was sequenced and phylogenetic analysis performed and subtype determined. Questionnaires documented demographic data. We examined factors associated with subtype using multinomial logistic regression, adjusted for study, age, and sex.

Results

Among 140 individuals (125 women and 15 men), subtype A1 predominated (54, 39%), followed by C (46, 33%), D (25, 18%) and unique recombinant forms (URFs) (15, 11%). There was weak evidence to suggest different subtype frequencies by study (for example, 18% URFs in the Kisesa cohort versus 5–9% in the hospitality facility-worker cohorts; adjusted relative-risk ratio (aRR) = 2.35 [95% CI 0.59,9.32]; global p = 0.09). Compared to men, women were less likely to have subtype D versus A (aRR = 0.12 [95% CI 0.02,0.76]; global p = 0.05). There was a trend to suggest lower relative risk of subtype D compared to A with older age (aRR = 0.44 [95% CI 0.23,0.85] per 10 years; global p = 0.05).

Conclusions

We observed multiple subtypes, confirming the complex genetic diversity of HIV-1 strains circulating in northern Tanzania, and found some differences between cohorts and by age and sex. This has important implications for vaccine design and development, providing opportunity to determine vaccine efficacy in diverse HIV-1 strains.

Repressive effect of primary virus replication on superinfection correlated with gut-derived central memory CD4(+) T cells in SHIV-infected Chinese rhesus macaques

A possible mechanism of susceptibility to superinfection with simian-human immunodeficiency virus (SHIV)-1157ipd3N4 was explored in twelve SHIV_SF162P3-infected Chinese rhesus macaques. Based on the kinetics of viral replication for the second infecting virus following SHIV-1157ipd3N4 inoculation, the monkeys were divided into two groups: those relatively resistant to superinfection (SIR) and those relatively sensitive to superinfection (SIS). We found that superinfection-resistant macaques had high primary viremia, whereas superinfection-sensitive macaques had low primary viremia, suggesting that primary SHIV_SF162P3 infection with a high viral-replication level would repress superinfection with a heterologous SHIV-1157ipd3N4. Although no correlation of protection against superinfection with virus-specific CD4⁺ T cell or CD8⁺ T cell immune responses from gut was observed prior to superinfection, superinfection susceptibility was strongly correlated with CD4⁺ Tcm cells from gut both prior to the second infecting virus inoculation and on day 7 after superinfection, but not with CD4⁺ Tem cells from gut or with CD4⁺ Tcm cells from peripheral blood and lymph node. These results point to the important roles of gut-derived CD4⁺ Tcm cells for the study of the mechanisms of protection against superinfection and the evaluation of the safety and efficacy of vaccines and therapies against acquired immune deficiency syndrome (AIDS).

HIV-1 superinfection occurs less frequently than initial infection in a cohort of high-risk Kenyan women

HIV superinfection (reinfection) has been reported in several settings, but no study has been designed and powered to rigorously compare its incidence to that of initial infection. Determining whether HIV infection reduces the risk of superinfection is critical to understanding whether an immune response to natural HIV infection is protective. This study compares the incidence of initial infection and superinfection in a prospective seroincident cohort of high-risk women in Mombasa, Kenya. A next-generation sequencing-based pipeline was developed to screen 129 women for superinfection. Longitudinal plasma samples at <6 months, >2 years and one intervening time after initial HIV infection were analyzed. Amplicons in three genome regions were sequenced and a median of 901 sequences obtained per gene per timepoint. Phylogenetic evidence of polyphyly, confirmed by pairwise distance analysis, defined superinfection. Superinfection timing was determined by sequencing virus from intervening timepoints. These data were combined with published data from 17 additional women in the same cohort, totaling 146 women screened. Twenty-one cases of superinfection were identified for an estimated incidence rate of 2.61 per 100 person-years (pys). The incidence rate of initial infection among 1910 women in the same cohort was 5.75 per 100 pys. Andersen-Gill proportional hazards models were used to compare incidences, adjusting for covariates known to influence HIV susceptibility in this cohort. Superinfection incidence was significantly lower than initial infection incidence, with a hazard ratio of 0.47 (CI 0.29-0.75, p = 0.0019). This lower incidence of superinfection was only observed >6 months after initial infection. This is the first adequately powered study to report that HIV infection reduces the risk of reinfection, raising the possibility that immune responses to natural infection are partially protective. The observation that superinfection risk changes with time implies a window of protection that coincides with the maturation of HIV-specific immunity.

Dynamics of HIV type 1 recombination following superinfection

There are currently few detailed studies describing HIV-1 recombination events or the potential impact of recombination on drug resistance. We describe here the viral recombination dynamics in a drug-naive patient initially infected with a circulating recombinant form 19 (CRF19) virus containing transmitted drug resistance mutations followed by superinfection with "wild-type" subtype B virus. Single genome analysis showed replacement of the primary CRF19 virus by recombinants of the CRF19 virus and the superinfecting subtype B virus. The CRF19/B recombinant virus dominating after superinfection had lost drug resistance mutations and at no time was the superinfecting subtype B variant found to be dominant in blood plasma. Furthermore, the detection of recombinant viruses in seminal plasma indicates the potential for onward transmission of these strains.

Gendered constructions of the impact of HIV and AIDS in the context of the HIV-positive seroconcordant heterosexual relationship

Introduction

This article explores the complex, dynamic and contextual frameworks within which men working in a mining community and their live-in long-term partners or spouses (termed “couples” in this study) respond to the introduction of HIV into their heterosexual relationships; the way in which partners adopt gendered positions in enabling them to make sense of their illness; how they negotiate their respective masculine and feminine roles in response to the need for HIV-related lifestyle changes; as well as the gendered nature of partner support in relation to antiretroviral therapy (ARV) adherence.

Methods

We conducted an in-depth qualitative study with a sample of 12 HIV-positive seroconcordant heterosexual couples in a South African mining organization. Transcripts based on semi-structured couple's interviews were analyzed using an inductive emergent thematic analytical method.

Results

The findings present compelling evidence that the impact of HIV and AIDS is mitigated, in the main, by the nature of the dyadic relationship. Where power and agency were skewed in accordance with traditional gender scripts, the impact of HIV and AIDS was deleterious in terms of negotiating disclosure, meeting expectations of care and support, and promoting treatment adherence. As a corollary, the study also revealed that where the relational dynamic evidenced a more equitable distribution of power, the challenge of negotiating illness was embraced in a way that strengthened the couples’ affiliation in profound ways, manifested not simply in a reduction in risk behaviours, but in both partner's courage to re-visit sensitive issues related to managing their relationship in the context of a debilitating illness.

Conclusions

Gendered positioning (by self and others) was found to play a crucial role in the way couples experienced HIV and ARV treatment, and underscored the positive role of a couples-counselling approach in the negotiation of the illness experience. However, as part of a broader social project, the findings highlight the need to address the shortcomings of a public health discourse on illness normalization that reifies and reinforces skewed gender relations. In essence, the findings make a compelling case for targeting couples as the primary unit of analysis and intervention in HIV and AIDS praxis, not only to enhance treatment and prevention outcomes, but to impact on and potentially transform the lived identity of such relationships, in AIDS-affected communities. We recommend early intervention with couples in terms of couples HIV testing, risk-reduction counselling and gender-based interventions giving couples opportunities to revisit and challenge their prevailing gendered identities. We note, however, that these efforts will be undermined in the long term, if the structural drivers of HIV risk and vulnerability, contained within macro-level social, economic and cultural practices, are not simultaneously addressed.

Molecular epidemiology of HIV-1 transmission in a cohort of HIV-1 concordant heterosexual couples from Dakar, Senegal

Background

A large number of HIV-1 infections in Africa occur in married couples. The predominant direction of intracouple transmission and the principal external origins of infection remain important issues of debate.

Methods

We investigated HIV-1 transmission in 46 HIV-1 concordant positive couples from Dakar, Senegal. Intracouple transmission was confirmed by maximum-likelihood phylogenetic analysis and pairwise distance comparisons of HIV-1 env gp41 sequences from both partners. Standardized interview data were used to deduce the direction as well as the external sources of the intracouple transmissions.

Results

Conservative molecular analyses showed linked viruses in 34 (74%) couples, unlinked viruses in 6 (13%) couples, and indeterminate results for 6 (13%) couples. The interview data corresponded completely with the molecular analyses: all linked couples reported internal transmission and all unlinked couples reported external sources of infection. The majority of linked couples (93%) reported the husband as internal source of infection. These husbands most frequently (82%) reported an occasional sexual relationship as external source of infection. Pairwise comparisons of the CD4 count, antiretroviral therapy status, and the proportion of gp41 ambiguous base pairs within transmission pairs correlated with the reported order of infection events.

Conclusions

In this suburban Senegalese population, a majority of HIV-1 concordant couples showed linked HIV-1 transmission with the husband as likely index partner. Our data emphasize the risk of married women for acquiring HIV-1 as a result of the occasional sexual relationships of their husbands.