Transmission Dynamics of HIV Subtype A in Tel Aviv, Israel: Implications for HIV Spread and Eradication

OBJECTIVE

Subtype-A HIV was introduced into Israel in the mid-1990s, predominantly by immigrants from the former Soviet Union (FSU) infected via intravenous drug use (IVDU). HIV subsequently spread beyond the FSU-IVDU community. In 2012, a mini-HIV outbreak, associated with injection of amphetamine cathinone derivatives, started in Tel Aviv, prompting public health response. To assess current trends and the impact of the outbreak and control measures, we conducted a phyloepidemiologic analysis.

METHOD

Demographic and clinical records and HIV sequences were compiled from 312 subtype-A HIV-infected individuals attending the Tel-Aviv Sourasky Medical Center between 2005-2016, where >40% of all subtype-A HIV-infected individuals in Israel are undergoing care. Molecular evolutionary genetics analysis (MEGA) and ayesian evolutionary analysis sampling trees (BEAST) programs were implemented in a phylogenetic analysis of pol sequences. Reconstructed phylogenies were assessed in the context of demographic information and drug-resistance profiles. Clusters were identified as sequence populations with posterior probability ≥0.95 of having a recent common ancestor.

RESULTS

After 2010, the subtype-A epidemic acquired substantial phylogenetic structure, having been unrecognized in studies covering the earlier period. Nearly 50% of all sequences were present in 11 distinct clusters consisting of 4-43 individuals. Cluster composition reflected transmission across ethnic groups, with men who have sex with men (MSM) playing an increasing role. The cathinone-associated cluster was larger than previously documented, containing variants that continued to spread within and beyond the IVDU community.

CONCLUSIONS

Phyloepidemiologic analysis revealed diverse clusters of HIV infection with MSM having a central role in transmission across ethic groups. A mini outbreak was reduced by public health measures, but molecular evidence of ongoing transmission suggests additional measures are necessary.

Role of Personality Characteristics and Sexual Orientation in the Risk for Sexual Addiction Among Israeli Men: Validation of a Hebrew Sex Addiction Scale

Men having sex with men are known to exhibit heightened sexual activity. This raises the conjecture that different sexual orientations exhibit different levels of sex addiction risk, which is also affected by personality. The present study examined the prevalence of the sex addiction risk within the context of sexual orientation and personality in Israeli men while also validating the Hebrew Bergen-Yale Sex Addiction Scale (HBYSAS). Results based on 177 participants showed that the HBYSAS is appropriate for assessing the risk for sex addiction in Israeli men. Furthermore, results showed that sex addiction risk varied with individuals’ sexual orientation while being modestly associated with higher neuroticism and lower conscientiousness.

HIV infection among men who have sex with men in Israel: a 35-year epidemiological and clinical overview, 1981-2015

BACKGROUND

This study is the first to describe major epidemiological trends and clinical characteristics among Israeli men who have sex with men (MSM), who are at a higher risk for HIV infection.

METHODS

This retrospective study includes all individuals reported to the Israeli Ministry of Health with HIV and self-identified as MSM between 1981 and 2015. The incidence rates of HIV infection and AIDS-defining diseases were analyzed and Kaplan-Meier survival estimates were calculated from time of HIV infection notification to AIDS diagnosis and death across three consecutive periods representing antiretroviral treatment availability.

RESULTS

The trend of increase in HIV incidence is similar to Western Europe, although Israeli rates are lower. Of 2052 HIV/AIDS Israeli MSM diagnosed during the follow-up, 296 (14.6%) developed AIDS. MSM constitute 28.4% of all HIV/AIDS cases and 41.5% of cases among men. Average times from HIV-notification until AIDS diagnosis were 15.5 [14.0-16.9], 16.0 [15.5-16.4], and 6.7 [6.7-6.8] years, within 1981-1996, 1997-2007, and 2008-2015, respectively. The HIV-incidence rate among Israeli MSM slightly declined from 2012, after peaking in 2011 at 6.2 per 100,000.

CONCLUSIONS

The recent reduction in HIV-incidence and in AIDS diagnoses among Israeli MSM is encouraging. Nevertheless, the disproportionate incidence of HIV among MSM requires sustained efforts to abate further infections.

Sexual intermingling of Arab and Jewish MSM in Israel: results of a molecular epidemiology study

OBJECTIVES

MSM comprise ∼30% of new HIV infections in Israel, a country with mixed Jewish and Arab populations. We molecularly characterized HIV-1 in the Arab and Jewish MSM (AMSM, JMSM) populations to reveal possible interethnical connections.

DESIGN

Cross-sectional study.

METHODS

All Israeli-born, HIV-1-infected MSM diagnosed between 2005 and 2016 (n = 1143) were cross-matched with the National Civil Registry to identify religion (Jews/Muslims/Christians). Transmitted drug-resistance mutations (TDRM) and HIV-1 subtypes were determined on the first partial protease and reverse transcriptase sequences from treatment-naive patients and phylogenetic trees were constructed.

RESULTS

Among MSM, 6.4% (73/1143) were Arabs and 93.6% (1070/1143) were Jews. Interestingly, a higher proportion of Arabs was identified among non-MSM (19%, 46/247 versus 6.4%, 73/1143, P < 0.01). Subtype analysis of 62 HIV-1 AMSM and 440 randomly selected HIV-1 JMSM sequences revealed 80.6, 8.1, 4.8 and 6.5% of AMSM and 82.3, 9.5, 4.1 and 4.1% of JMSM had B, A, C and non-A/B/C, respectively. Overall, 13.1% (66/502) had TDRM; reverse transcriptase-K103N/S, M184 V, T215S and protease-L90M were the most common. TDRM prevalence was not significantly higher in JMSM compared to AMSM (P = 0.1) and no temporal changes were observed in their frequency. Phylogenetic analysis demonstrated AMSM and JMSM clusters including L90M, K103N/S or T215S TDRM.

CONCLUSION

Intermingling of AMSM and JMSM HIV-1 in clusters of HIV-1 sequences suggest interethnical sexual contacts among these MSM. Interventions aiming to prevent HIV-transmission in MSM should similarly address both populations groups. The high TDRM frequency requires continuation of resistance testing.

New Challenges in HIV Research: Combining Phylogenetic Cluster Size and Epidemiological Data

An exciting new direction in HIV research is centered on using molecular phylogenetics to understand the social and behavioral drivers of HIV transmission. SPOT was an intervention designed to offer HIV point of care testing to men who have sex with men at a community-based site in Montreal, Canada; at the time of testing, a research questionnaire was also deployed to collect data on socio-demographic and behavioral characteristics of participating men. The men taking part in SPOT could be viewed, from the research perspective, as having been recruited via a convenience sample. Among men who were found to be HIV positive, phylogenetic cluster size was measured using a large cohort of HIV-positive individuals in the province of Quebec. The cluster size is likely subject to under-estimation. In this paper, we use SPOT data to evaluate the association between HIV transmission cluster size and the number of sex partners for MSM, after adjusting for the SPOT sampling scheme and correcting for measurement error in cluster size by leveraging external data sources. The sampling weights for SPOT participants were calculated from another study of men who have sex with men in Montreal by fitting a weight-adjusted model, whereas measurement error was corrected using the simulation-extrapolation conditional on covariates approach.

Molecular Analysis of Human Immunodeficiency Virus Type 1 (HIV-1)-Infected Individuals in a Network-Based Intervention (Transmission Reduction Intervention Project): Phylogenetics Identify HIV-1-Infected Individuals With Social Links

Background

The Transmission Reduction Intervention Project (TRIP) is a network-based intervention that aims at decreasing human immunodeficiency virus type 1 (HIV-1) spread. We herein explore associations between transmission links as estimated by phylogenetic analyses, and social network-based ties among persons who inject drugs (PWID) recruited in TRIP.

Methods

Phylogenetic trees were inferred from HIV-1 sequences of TRIP participants. Highly supported phylogenetic clusters (transmission clusters) were those fulfilling 3 different phylogenetic confidence criteria. Social network-based ties (injecting or sexual partners, same venue engagement) were determined based on personal interviews, recruitment links, and field observation.

Results

TRIP recruited 356 individuals (90.2% PWID) including HIV-negative controls; recently HIV-infected seeds; long-term HIV-infected seeds; and their social network members. Of the 150 HIV-infected participants, 118 (78.7%) were phylogenetically analyzed. Phylogenetic analyses suggested the existence of 13 transmission clusters with 32 sequences. Seven of these clusters included 14 individuals (14/32 [43.8%]) who also had social ties with at least 1 member of their cluster. This proportion was significantly higher than what was expected by chance.

Conclusions

Molecular methods can identify HIV-infected people socially linked with another person in about half of the phylogenetic clusters. This could help public health efforts to locate individuals in networks with high transmission rates.

Comparison between next-generation and Sanger-based sequencing for the detection of transmitted drug-resistance mutations among recently infected HIV-1 patients in Israel, 2000-2014

INTRODUCTION

Transmitted drug-resistance mutations (TDRM) may hamper successful anti-HIV-1 therapy and impact future control of the HIV-1 epidemic. Recently infected, therapy-naïve individuals are best suited for surveillance of such TDRM. In this study, TDRM, detected by next-generation sequencing (NGS) were compared to those identified by Sanger-based population sequencing (SBS) in recently infected HIV-1 patients.

METHODS

Historical samples from 80 recently infected HIV-1 patients, diagnosed between 2000 and 2014, were analysed by MiSeq (NGS) and ABI (SBS). DeepChek-HIV (ABL) was used for interpretation of the results.

RESULTS

Most patients were males (80%); Men who have sex with men (MSM) was the major transmission group (58.8%). Overall, TDRM were detected in 31.3% of patients by NGS and 8.8% by SBS, with SBS TDRM restricted to persons infected with subtype B. All SBS-detected TDRM were identified by NGS. The prevalence of TDRM impacting protease inhibitors (PI), nucleoside reverse transcriptase inhibitors (NRTI) and non-nucleoside reverse transcriptase inhibitors (NNRTI) was 11.3, 26.2 7.5%, respectively, in NGS analyses and 0, 3.8 and 5%, respectively, in SBS analyses. More patients with NGS and SBS TDRM were identified in 2008-2014 (37.2% or 13.9%, respectively) compared to 2000-2007 (24.3% or 2.7%, respectively), and a significantly greater number of these patients had multiple NGS TDRM. The most abundant, albeit, minor-frequency RT TDRM, were the K65R and D67N, while K103N, M184V and T215S were high-frequency mutations. Minor TDRM did not become a major variant in later samples and did not hinder successful treatment.

CONCLUSIONS

NGS can replace SBS for mutation detection and allows for the detection of low-frequency TDRM not identified by SBS. Although rates of TDRM in Israel continued to increase from 2000 to 2014, minor TDRM did not become major species. The need for ongoing surveillance of low-frequency TDRM should be revisited in a larger study.

Large cluster outbreaks sustain the HIV epidemic among MSM in Quebec

OBJECTIVE

HIV-1 epidemics among MSM remain unchecked despite advances in treatment and prevention paradigms. This study combined viral phylogenetic and behavioural risk data to better understand underlying factors governing the temporal growth of the HIV epidemic among MSM in Quebec (2002-2015).

METHODS

Phylogenetic analysis of pol sequences was used to deduce HIV-1 transmission dynamics (cluster size, size distribution and growth rate) in first genotypes of treatment-naïve MSM (2002-2015, n = 3901). Low sequence diversity of first genotypes (0-0.44% mixed base calls) was used as an indication of early-stage infection. Behavioural risk data were obtained from the Montreal rapid testing site and primary HIV-1-infection cohorts.

RESULTS

Phylogenetic analyses uncovered high proportion of clustering of new MSM infections. Overall, 27, 45, 48, 53 and 57% of first genotypes within one (singleton, n = 1359), 2-4 (n = 692), 5-9 (n = 367), 10-19 (n = 405) and 20+ (n = 1277) cluster size groups were early infections (<0.44% diversity). Thirty viruses within large 20+ clusters disproportionately fuelled the epidemic, representing 13, 25 and 42% of infections, first genotyped in 2004-2007 (n = 1314), 2008-2011 (n = 1356) and 2012-2015 (n = 1033), respectively. Of note, 35, 21 and 14% of MSM belonging to 20+, 2-19 and one (singleton) cluster groups were under 30 years of age, respectively. Half of persons seen at the rapid testing site (2009-2011, n = 1781) were untested in the prior year. Poor testing propensity was associated with fewer reported partnerships.

CONCLUSION

Addressing the heterogeneity in transmission dynamics among HIV-1-infected MSM populations may help guide testing, treatment and prevention strategies.

Transmitted HIV Drug Resistance Is High and Longstanding in Metropolitan Washington, DC

BACKGROUND

Washington, DC, has 2.5% human immunodeficiency virus (HIV) prevalence, 3.9% among African Americans. Antiretrovirals (ARTs) are the cornerstone for treatment and prevention. Monitoring changes in transmitted drug resistance (TDR) is critical for effective HIV care.

METHODS

HIV genotype data for individuals enrolled in research studies in metropolitan Washington, D.C., were used to identify TDR using the World Health Organization mutation list [Bennett DE, Camacho RJ, Otelea D, et al. Drug resistance mutations for surveillance of transmitted HIV-1 drug-resistance: 2009 update. PloS One 2009; 4:e4724]. HIV phylogenies were reconstructed using maximum likelihood and Bayesian methods. HIV transmission clusters were supported by 1000 bootstrap values >0.70 and posterior probability >0.95 of having a common ancestor.

RESULTS

Among 710 individuals enrolled in 1994-2013, the median age was 38.6 years, 46.2% were female, and 53.3% were African-American. TDR was 22.5% among 566 treatment-naive individuals; 15.8% had nucleoside/nucleotide reverse transcriptase inhibitor (NRTI) resistance, 9.8% had nonnucleoside reverse-transcriptase inhibitor (NNRTI) resistance, and 4.2% had protease inhibitor (PI) resistance. Single class TDR was 10.0%, 5.1%, and 1.6% to NRTIs, NNRTIs, and PIs. Dual TDR to PI and NRTI was seen in 1.6%, NRTI and NNRTI in 3.4%, and triple class TDR in 0.9%. TDR frequency decreased from 1994-2006 (27.1%) to 2007-2013 (19.4%; P = .02). Only 6/79 (7.6%) individuals within transmission clusters had evidence of TDR.

DISCUSSIONS

We identified high prevalence of TDR among HIV-infected individuals in metropolitan Washington, DC, regardless of gender. Active surveillance for TDR is needed to guide ART usage and analyses of risk group contributions to HIV transmission and resistance.

Connecting the dots: network data and models in HIV epidemiology

Effective HIV prevention requires knowledge of the structure and dynamics of the social networks across which infections are transmitted. These networks most commonly comprise chains of sexual relationships, but in some populations, sharing of contaminated needles is also an important, or even the main mechanism that connects people in the network. Whereas network data have long been collected during survey interviews, new data sources have become increasingly common in recent years, because of advances in molecular biology and the use of partner notification services in HIV prevention and treatment programmes. We review current and emerging methods for collecting HIV-related network data, as well as modelling frameworks commonly used to infer network parameters and map potential HIV transmission pathways within the network. We discuss the relative strengths and weaknesses of existing methods and models, and we propose a research agenda for advancing network analysis in HIV epidemiology. We make the case for a combination approach that integrates multiple data sources into a coherent statistical framework.

Clinical, epidemiological and treatment failure data among HIV-1 non-B-infected patients in the Spanish AIDS Research Network Cohort

INTRODUCTION

The prevalence of HIV-1 non-B variants is increasing in Spain, showing a higher number of transmitted drug resistance mutations (TDR) since 2002. This study presents the features of non-B-infected patients enrolled in the cohort of antiretroviral treatment (ART) naïve HIV-infected patients included in the Research Network on HIV/AIDS (CoRIS).

METHODS

The study includes a selected group of HIV-1 non-B-infected subjects from 670 subjects with pol sequences collected from 2004 to 2008 in the CoRIS cohort. Epidemiological-clinical-virological data were analyzed since cohort entry until October 2011, considering the presence or absence of treatment failure (TF).

RESULTS

Eighty two non-B infected subjects with known HIV-1 variants were selected from 2004 to 2008 in the CoRIS cohort, being mainly female, immigrants, infected by recombinant viruses, and by heterosexual route. They had an intermediate TDR rate (9.4%), a high rate of TF (25.6%), of losses to follow-up (35%), of coinfections (32.9%), and baseline CD4+ counts ≥350cells/mm(3) (61.8%). Non-B subjects with TF showed higher rates of heterosexual infection (85.7% vs. 69.5%, p<0.05), tuberculosis (30.8% vs. 9.1%, p=0.10) and hepatitis C (23.8% vs. 13.9%, p=0.34) coinfections and lower rates of syphilis (0% vs. 21.9%, p<0.05), and had more frequently received first-line ART including protease inhibitors (PIs) than patients without TF (70% vs. 30%, p<0.05). Interestingly, infection with non-B variants reduced the risk of TDR to nucleoside reverse transcriptase inhibitors and increased the risk to PIs.

CONCLUSION

HIV-1 non-B-infected patients in Spain had a particular epidemiological and clinical profile that should be considered during their clinical management.

A Population-Structured HIV Epidemic in Israel: Roles of Risk and Ethnicity

Background

HIV in Israel started with a subtype-B epidemic among men who have sex with men, followed in the 1980s and 1990s by introductions of subtype C from Ethiopia (predominantly acquired by heterosexual transmission) and subtype A from the former Soviet Union (FSU, most often acquired by intravenous drug use). The epidemic matured over the last 15 years without additional large influx of exogenous infections. Between 2005 and 2013 the number of infected men who have sex with men (MSM) increased 2.9-fold, compared to 1.6-fold and 1.3-fold for intravenous drug users (IVDU) and Ethiopian-origin residents. Understanding contemporary spread is essential for effective public health planning.

Methods

We analyzed demographic and virologic data from 1,427 HIV-infected individuals diagnosed with HIV-I during 1998–2012. HIV phylogenies were reconstructed with maximum-likelihood and Bayesian methods.

Results

Subtype-B viruses, but not A or C, demonstrated a striking number of large clusters with common ancestors having posterior probability ≥0.95, including some suggesting presence of transmission networks. Transmitted drug resistance was highest in subtype B (13%). MSM represented a frequent risk factor in cross-ethnic transmission, demonstrated by the presence of Israeli-born with non-B virus infections and FSU immigrants with non-A subtypes.

Conclusions

Reconstructed phylogenetic trees demonstrated substantial grouping in subtype B, but not in non-MSM subtype-A or in subtype-C, reflecting differences in transmission dynamics linked to HIV transmission categories. Cross-ethnic spread occurred through multiple independent introductions, with MSM playing a prevalent role in the transmission of the virus. Such data provide a baseline to track epidemic trends and will be useful in informing and quantifying efforts to reduce HIV transmission.

Prevalence and associated factors for HIV-1 transmitted drug resistance in voluntary clients for counseling and testing in Southern Taiwan

BACKGROUND

According to the World Health Organization, HIV-transmitted drug resistance (TDR) is increasing. We analyzed voluntary counseling test data from a hospital in Southern Taiwan to investigate the TDR pattern in Southern Taiwan, the potential relationship between sexual behavior and HIV transmission, and HIV drug-resistant strain transmission.

METHODS

Genotypic resistance assays were performed on treatment-naïve HIV patients recruited from voluntary counseling testing (VCT) in Southern Taiwan from 2007 to 2011. Drug resistance-associated mutations were interpreted with Stanford University HIV Drug Resistance Database HIVdb program. Socio-demographics and sexual activity were recorded from the VCT questionnaire. Logistic regression analysis was used to analyze the risk factors for TDR, and a phylogenetic tree was constructed to elucidate the pattern of HIV drug-resistant strains.

RESULTS

Among the 161 treatment-naïve HIV-infected patients, most were men who reported having sex with men. The overall TDR rate was 10.6%. Patients with a history of sexually transmitted diseases had a 7.8-fold higher risk of becoming infected with genotypic resistant strains.

CONCLUSION

In Southern Taiwan, the HIV TDR rate was 10.6% among those receiving VCT. Our findings suggest that sexual behavior may play an important role in HIV drug-resistant strain transmission.

Comparable long-term efficacy of Lopinavir/Ritonavir and similar drug-resistance profiles in different HIV-1 subtypes

BACKGROUND

Analysis of potentially different impact of Lopinavir/Ritonavir (LPV/r) on non-B subtypes is confounded by dissimilarities in the conditions existing in different countries. We retrospectively compared its impact on populations infected with subtypes B and C in Israel, where patients infected with different subtypes receive the same treatment.

METHODS

Clinical and demographic data were reported by physicians. Resistance was tested after treatment failure. Statistical analyses were conducted using SPSS.

RESULTS

607 LPV/r treated patients (365 male) were included. 139 had HIV subtype B, 391 C, and 77 other subtypes. At study end 429 (71%) were receiving LPV/r. No significant differences in PI treatment history and in median viral-load (VL) at treatment initiation and termination existed between subtypes. MSM discontinued LPV/r more often than others even when the virologic outcome was good (p = 0.001). VL was below detection level in 81% of patients for whom LPV/r was first PI and in 67% when it was second (P = 0.001). Median VL decrease from baseline was 1.9±0.1 logs and was not significantly associated with subtype. Median CD4 increase was: 162 and 92cells/µl, respectively, for patients receiving LPV/r as first and second PI (P = 0.001), and 175 and 98, respectively, for subtypes B and C (P<0.001). Only 52 (22%) of 237 patients genotyped while under LPV/r were fully resistant to the drug; 12(5%) were partially resistant. In48%, population sequencing did not reveal resistance to any drug notwithstanding the virologic failure. No difference was found in the rates of resistance development between B and C (p = 0.16).

CONCLUSIONS

Treatment with LPV/r appeared efficient and tolerable in both subtypes, B and C, but CD4 recovery was significantly better in virologically suppressed subtype-B patients. In both subtypes, LPV/r was more beneficial when given as first PI. Mostly, reasons other than resistance development caused discontinuation of treatment.

The emerging and re-emerging human immunodeficiency virus epidemics in Europe

We provide a summary of the current status of the human immunodeficiency virus (HIV) epidemic, including data on the transmission of drug-resistant virus in the European Region of the WHO. The review was conducted by searching the reports of the European Centre for Disease Prevention and Control and the United Nations General Assembly Special Session country reports to identify the number of HIV cases reported in 2002-2011, the number of HIV tests performed, and the results of the most recent HIV surveys in at-risk groups. In the West, a 5-year linear trend analysis suggests an increase in the number of reported HIV cases in Belgium, Greece, and Iceland, and a decline in The Netherlands, Ireland, Portugal, Switzerland, and the UK. In the Centre, the number of reported cases increased in Bulgaria and Turkey, and in the East, the number of reported cases increased in Armenia, Georgia, and Ukraine. Estonia and Latvia reported a significant downward trend. HIV transmission in men who have sex with men (MSM) and heterosexual transmission accounted for, respectively, 40% and 38% of newly reported HIV cases in the West in 2011, whereas the epidemic in the Centre is predominantly concentrated in MSM. Although injection drug use remains the key driving force of the epidemic in the East, there is increasing evidence of sexual transmission from the core groups of injection drug users, and increasing spread within MSM. The pattern of transmitted drug resistance (TDR) is heterogeneous accross Europe; a significant number of clusters of TDR have been recently observed in several European countries.

Thirty years of HIV in Israel: current epidemiology and future challenges

OBJECTIVE

The HIV/AIDS burden in Israel is increasing. This study aims to describe the nationwide-HIV epidemiology in the last 30 years and highlight areas of concern in HIV/AIDS control.

DESIGN

Descriptive study.

SETTING

The National HIV/AIDS Registry in Israel.

PARTICIPANTS

All individuals who were reported with HIV/AIDS in Israel.

PRIMARY OUTCOME MEASURES

Classification of HIV/AIDS cases by risk groups, calculation of annual trend analysis and estimation of HIV transmission rates by dividing the annual HIV/AIDS-incidence by the prevalence, while the number of newly diagnosed HIV/AIDS cases reported was a proxy of the incidence.

RESULTS

From 1981 to 2010, 6579 HIV/AIDS cases were reported in an upward trend from 3.6 new HIV diagnoses/100 000 population in 1986 to 5.6 in 2010. Immigrants from countries of generalised epidemic (ICGE) comprised 2717 (41.3%) of all cases: 2089 (76.9%) were Israeli citizens and 628 (23%) were non-Israeli citizens, mostly migrant workers. The majority (N=2040) of ICGE Israeli citizens were born in Ethiopia. Only 796 (12.1%) of all HIV/AIDS cases were heterosexuals who were non-ICGE and not injecting drug users (IDUs). IDU comprised 13.4% (N=882) of all cases. Men who have sex with men (MSM) accounted for 33.2% (N=1403) of all men reported, while the annual number of MSM reported with HIV/AIDS has quadrupled between 2000 and 2010. It is estimated that the HIV point prevalences in 2010 for Ethiopian-born Israeli citizens, IDU and MSM aged 16-45 were 1805, 1492 and 3150, respectively. The crude estimated transmission rates among Israeli citizens, excluding the Ethiopian-born, was 10.5, while among Ethiopian-born Israeli citizens, IDU and MSM the rates were 3.6, 6.3 and 13.2, respectively.

CONCLUSIONS

The HIV/AIDS burden in Israel is low among heterosexuals and higher in risk-groups. Among these risk groups, the highest HIV transmission rate was in MSM, followed by IDU and ICGE. Culturally sensitive and focused prevention interventions should be tailored exclusively for each of the vulnerable risk groups.

Future of phylogeny in HIV prevention

The success of the HIV Prevention Trials Network 052 trial has led to revisions in HIV-1 treatment guidelines. Antiretroviral therapy may reduce the risk of HIV-1 transmissions at the population level. The design of successful treatment as prevention interventions will be predicated on a comprehensive understanding of the spatial, temporal, and biological dynamics of heterosexual men who have sex with men and intravenous drug user epidemics. Viral phylogenetics can capture the underlying structure of transmission networks based on the genetic interrelatedness of viral sequences and cluster networks that could not be otherwise identified. This article describes the phylogenetic expansion of the Montreal men who have sex with men epidemic over the last decade. High rates of coclustering of primary infections are associated with 1 infection leading to 13 onward transmissions. Phylogeny substantiates the role of primary and recent stage infection in transmission dynamics, underlying the importance of timely diagnosis and immediate antiretroviral therapy initiation to avert transmission cascades.

Transmission patterns of HIV-subtypes A/AE versus B: inferring risk-behavior trends and treatment-efficacy limitations from viral genotypic data obtained prior to and during antiretroviral therapy

BACKGROUND

HIV subtypes A and CRF01_AE (A/AE) became prevalent in Israel, first through immigration of infected people, mostly intravenous-drug users (IVDU), from Former Soviet-Union (FSU) countries and then also by local spreading. We retrospectively studied virus-transmission patterns of these subtypes in comparison to the longer-established subtype B, evaluating in particular risk-group related differences. We also examined to what extent distinct drug-resistance patterns in subtypes A/AE versus B reflected differences in patient behavior and drug-treatment history.

METHODS

Reverse-transcriptase (RT) and protease sequences were retrospectively analyzed along with clinical and epidemiological data. MEGA, ClusalX, and Beast programs were used in a phylogenetic analysis to identify transmission networks.

RESULTS

318 drug-naive individuals with A/AE or patients failing combination antiretroviral therapy (cART) were identified. 61% were IVDU. Compared to infected homosexuals, IVDU transmitted HIV infrequently and, typically, only to a single partner. 6.8% of drug-naive patients had drug resistance. Treatment-failing, regimen-stratified subtype-A/AE- and B-patients differed from each other significantly in the frequencies of the major resistance-conferring mutations T215FY, K219QE and several secondary mutations. Notably, failing boosted protease-inhibitors (PI) treatment was not significantly associated with protease or RT mutations in either subtype.

CONCLUSIONS

While sizable transmission networks occur in infected homosexuals, continued HIV transmission among IVDU in Israel is largely sporadic and the rate is relatively modest, as is that of drug-resistance transmission. Deviation of drug-naive A/AE sequences from subtype-B consensus sequence, documented here, may subtly affect drug-resistance pathways. Conspicuous differences in overall drug-resistance that are manifest before regimen stratification can be largely explained in terms of treatment history, by the different efficacy/adherence limitations of older versus newer regimens. The phenomenon of treatment failure in boosted-PI-including regimens in the apparent absence of drug-resistance to any of the drugs, and its relation to adherence, require further investigation.

HIV testing and antiretroviral treatment strategies for prevention of HIV infection: impact on antiretroviral drug resistance

'Test and treat' is a strategy in which widespread screening for human immunodeficiency virus (HIV) is followed by immediate antiretroviral therapy for those testing positive, thereby potentially reducing infectiousness in larger cohorts of infected patients. However, there is a concern that test and treat could lead to increased the levels of transmissible drug-resistant HIV, especially if viral load and/or drug resistance is not routinely monitored. Reviews of the existing literature show that up to now, even in the absence of laboratory tests, drug resistance has not created major problems in sub-Saharan Africa. Here, we discuss the current evidence for the effectiveness of a preventive test and treat approach and the challenges and implications for daily clinical practice and public health.

Emergence of an HIV-1 cluster harbouring the major protease L90M mutation among treatment-naïve patients in Tel Aviv, Israel

OBJECTIVE

Drug resistance-associated mutations (DRMs) among HIV-1 treatment-naïve patients have increased in recent years. Their incidence and prevalence in various exposure risk categories (ERCs) were evaluated.

DESIGN

Plasma samples of HIV-1 treatment-naïve patients diagnosed between 2001 and 2009 at the Tel Aviv Medical Center were screened for DRMs.

METHODS

Samples obtained from patients following the HIV diagnosis were analysed retrospectively. Genotyping was carried out using the Trugene HIV-1 genotype kit (Siemens, Berkeley, CA, USA). Phylogenetic relationships among viral sequences were estimated using the maximum likelihood method.

RESULTS

Thirty-eight of the 266 analysed sequences (14.3%) had DRMs, all occurring exclusively in the group of men who have sex with men (MSM). The rate of DRMs has constantly risen, reaching a peak of 21.9% in 2009. Notably, protease inhibitor (PI) DRMs became the most frequent DRMs in 2009. Phylogenetic analysis showed a tight cluster comprising 13 of 14 viruses harbouring the L90M major PI resistance mutation, suggesting a single infection source.

CONCLUSION

There was an unexpectedly high rate of the major L90M PI resistance mutation in the MSM group. The clustered transmission of this mutation might be related to a high-risk sexual behaviour. Added to nonnucleoside reverse transcriptase inhibitor and nucleoside reverse transcriptase inhibitor resistance mutations, such a PI mutation may limit future therapeutic options for this particular patient population.