Retrovirology

Background: A cross-sectional study on 625 Female Sex Workers (FSWs) was conducted between 2000 and 2002 in 6 cities in Argentina. This study describes the genetic diversity and the resistance profile of the HIV-infected subjects. Results: Seventeen samples from HIV positive FSWs were genotyped by env HMA, showing the presence of 9 subtype F, 6 subtype B and 2 subtype C. Sequence analysis of the protease/RT region on 16 of these showed that 10 were BF recombinants, three were subtype B, two were subtype C, and one sample presented a dual infection with subtype B and a BF recombinant. Full-length genomes of five of the protease/RT BF recombinants were also sequenced, showing that three of them were CRF12_BF. One FSW had a dual HIV-1 infection with subtype B and a BF recombinant. The B sections of the BF recombinant clustered closely with the pure B sequence isolated from the same patient. Major resistance mutations to antiretroviral drugs were found in 3 of 16 (18.8%) strains. Conclusion: The genetic diversity of HIV strains among FSWs in Argentina was extensive; about three-quarters of the samples were infected with diverse BF recombinants, near twenty percent had primary ART resistance and one sample presented a dual infection. Heterosexual transmission of genetically diverse, drug resistant strains among FSWs and their clients represents an important and underestimated threat, in Argentina. Background The genetic diversity of human immunodeficiency virus type 1 (HIV-1) was recognized early in the epidemic. Phylogenetic analyses of HIV-1 have revealed the presence of 9 subtypes (A-D, F-H, J and K) and at least 34 circulating recombinant forms (CRFs) worldwide. A great variety of Published: 13 August 2007 Retrovirology 2007, 4:58 doi:10.1186/1742-4690-4-58 Received: 26 February 2007 Accepted: 13 August 2007 This article is available from: http://www.retrovirology.com/content/4/1/58 © 2007 Pando et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Page 1 of 9 (page number not for citation purposes) Retrovirology 2007, 4:58 http://www.retrovirology.com/content/4/1/58 unique recombinant structures have also been identified [1]. Previous studies have highlighted the complex nature of the HIV epidemic in Argentina and revealed the presence of two independent epidemics: one among men who have sex with men (MSM) where the viral strains are mostly subtype B, and the second among heterosexuals and injecting drug users (IDUs) where BF recombinants predominate [2,3]. Further sequencing studies have revealed the presence of a new CRF, CRF12_BF [4]. More recently, phylogenetic analysis of strains from Argentina has described different subtypes and recombinants in newly diagnosed patients [5], including one triple recombinant between subtypes B, C and F [6]. Female sex workers (FSWs) have been at high-risk of infection since the beginning of the HIV epidemic all over the world. Multiple sex partners, irregular condom use, and co-infection with other sexual transmitted infections (STIs) are the principal risk factors for HIV infection among FSWs [7]. During March 2000 and March 2002, a cross-sectional seroprevalence study was conducted among 625 FSWs in six cities in Argentina (Buenos Aires, Salta, Rosario, Córdoba, Mendoza and La Plata) with the objective of estimating the HIV prevalence and associated risk factors [8]. The findings of this study clearly indicated that this population of FSWs was found to be at high risk of STIs, as illustrated by the high prevalence found for syphilis (45.7%), hepatitis B (14.4%), HIV (3.2%), hepatitis C (4.3%), and HTLV-I/II (1.6%) infections. The study also showed that this group has sexual contact with men from other countries: 51.2% of them reported having had sexual contact with foreigners, mostly from Brazil and Paraguay. In addition, FSWs have multiple exposures due to the number of sex partners they have over time (mean per week: 14). The main objective of this retrospective study was to describe the genetic diversity and antiretroviral resistance profile of HIV strains among Argentinean FSWs who represent an important core group, which can serve as a link with subsequent transmission to the heterosexually active population at-large. Methods Study population Details of the enrollment and data collection procedures for this study have been reported previously [8]. FSWs (n = 625) were recruited through a non-governmental organization (AMMAR: Asociacion de Mujeres Meretrices de Argentina) for a cross-sectional seroprevalence study. Confidential one-on-one interviews were conducted onsite by health care workers. During these encounters, the study was explained and subjects were invited to participate. Only those subjects who were willing to participate were provided written informed consent, enrolled, and sampled. Study participants were interviewed using a standardized questionnaire with information regarding sociodemographic characteristics, sexual practices, current or past use of illegal drugs, and prior history of STIs. FSWs declared not to be under HIV antiretroviral treatment. This research was reviewed by the institutional review boards and scientific ethical committees at the University of Buenos Aires and at the U.S. Naval Medical Research Center (NMRC) in the United States and was conducted in compliance with all federal regulations governing the protection of human subjects. Blood sampling and genotyping procedures Peripheral blood mononuclear cells (PBMCs) from HIVinfected FSWs recruited during the seroprevalence study were obtained, separated by Ficoll-Hypaque technique and maintained at -70°C. PBMCs were used for DNA extraction by the QIAmp DNA extraction kit (QIAgen, Valencia, CA, USA). All 17 samples were subjected to PCR amplification in env, 16 were amplified at the protease/ reverse transcriptase (pro/RT) region, and 6 samples were subjected to near full-length amplification. The env region was amplified using ED3/ED14 as outer primers and ED31/ED33 as inner primers. Heteroduplex mobility assay (HMA) was performed with the second-round PCR products using nine reference standards as previously described [9]. The pro/RT region was amplified using Por5F/RT3474R in the first round and Pro3F/ProRT for the second round. The conditions of the PCR amplification have been previously described [10]. Near full-length sequences were done with primers MSF12b and OFMR1 for the first-round. The secondround amplification was completed using 1 μl of the firstround product and primers F2NST and UNINEF 7. This nested strategy amplifies about 9000 kb of the HIV genome and was slightly modified from that used previously [11,12]. The amplified products were then sequenced with Big Dye terminators using an ABI 3100 automated sequencer (Applied Biosystems Inc, Foster City CA). Phylogenetic analysis was performed by first aligning the sequences obtained with reference sequences using the program MacGDE [13] followed by a Neighbor-joining method with Kimura's two-parameter model of distance calculation; bootstrap analysis was performed with 100 replicas. Phylogenetic trees were constructed using MEGA3 [14,15]. Recombinant analysis was performed using SimPlot v.3.5.1 [16]. Resistance profile The genotypic antiretroviral drug resistance profile was examined by examining for mayor mutations which have Page 2 of 9 (page number not for citation purposes) Retrovirology 2007, 4:58 http://www.retrovirology.com/content/4/1/58 been associated with reduced susceptibility to protease and RT inhibitors, as reported by the International AIDS Society-USA in April 2005 (Stanford University HIV Drug Resistance Database). RT: M41L, A62V, K65R, D67N, T69D, 69 insert, K70R, L74V, V75I, F77L, L100I, K103N, V106A, V106M, V108I, Y115F, F116Y, Q151M, Y181C, Y181I, M184V, M184I, Y188C, Y188L, Y188H, G190A, G190S, L210W, T215Y, T215F, K219Q, K219E, P225H, M230L, and P236L; protease: D30N, M46I, M46L, G48V, I50V, V82A, V82S, V82F, V82T, I84V, and L90M. Results Characteristics of the study participants A total of 625 FSWs were enrolled in the seroprevalence study and 20 tested HIV positive, reflecting a prevalence of 3.2% [8]. These HIV positive samples were from different cities in the country, one from La Plata (1/100, 1.0%), two from Cordoba (2/86, 2.3%), two from Mendoza (2/33, 6.1%), five from Salta (5/98, 5.1%) and ten from Buenos Aires (10/296, 3.4%). No infections were detected in Rosario (0/12) Genetic Characterization Heteroduplex Mobility Assay (HMA) Out of 20 HIV positive samples, envelope HMA was completed in 17 samples. As shown in Table 1, env subtype F was found in 52.9% (n = 9), subtype B in 35.3% (n = 6) and subtype C in 11.8% (n = 2). Sequencing analysis Sequencing analysis of the pro/RT region was performed in 16 of the samples (there was no sufficient pro/RT gen amplified product in one sample). Phylogenetic analysis of these samples is shown in Figure 1. Ten samples (62.5%) were found to be BF recombinants, three were subtype B, two were subtype C, and one sample presented a dual infection with subtype B and a BF recombinant. All of the samples that were characterized as subtype F (n = 9) by envelope HMA, were BF recombinants in the pro/ RT gen region (Table 1). The two samples classified as subtype C by HMA were also subtype C in pro/RT gen region. Of the samples that were characterized as subtype B by envelope HMA (n = 6), 3 were subtype B in pro/RT and one was a BF recombinant. The near full-length genomes of 5 of the pro/RT BF recombinants were also sequenced (Figure 2). Simplot and Bootscan analysis of these 5 samples showed that 3 of them were CRF12_BF and 2 were unique recombinant forms (URFs, data not shown). The 2 subtype C strains sign


Managed health care: US evidence and lessons for the National Health Service
Ray Robinson and Andrea Steiner Buckingham;Bristol, PA: Open University Press, 1998, pp. xiv, 206, ISBN 0335199488 (pbk.), 0335199496 (hb) Managed care is attracting considerable attention world-wide as a means of controlling the costs of health care in ways that maintain or improve quality and outcomes.In practice it is not a single mechanism but a range of techniques and incentive structures, some of which have long been features of the UK National Health Service (NHS) and of other health care systems.But the concept, the overall approach, and some of the particular micro-management techniques-such as disease management, utilisation review, physician profiling, and use of guidelines and protocols-have been developed extensively in the United States.
The book is introduced by Professor Chris Ham, emphasising that 'policy makers in a number of countries are reviewing the future of health services.Those countries that have traditionally relied on a market in health care are making greater use of regulation and planning.Equally, those countries which have traditionally relied on regulation and planning are moving towards a more competitive approach.In no country is there complete satisfaction with existing methods of financing and delivery, and everywhere there is a search for new policy instruments'.
It was this reason that the Department of Healthwhen thinking about the possible application of managed care techniques in the NHS-decided to commission a review of US research evidence and its relevance for the NHS.This review was carried out by Ray Robinson and Andrea Steiner who have later made their work more widely available through the book: ''Managed Health Care''.
The book contains a carefully collected and analysed set of findings on the performance of managed care organisations and the effectiveness of the specific techniques as applied in the United States.
Through the discussion of up-to-date evidence on the development of the NHS total purchasing projects the authors also show how managed care techniques are being developed in the NHS.Sensibly they are at pains to point out that US experience should be seen as a source of ideas for possible use in the UK context rather than a blueprint for direct application.Chapter 1 presents a review of the different models of managed care in the USA and a discussion of the various techniques used in an effort to contain costs without compromising quality and outcomes.As the chapter shows, there is currently an enormous variety in the forms of managed care organisations (MCO).
Methods for managing care discussed in Chapter 1 include financial incentives, techniques for managing clinical activity and patient-focused approaches.
Financial incentives are shown to apply at both the organisational level, in the form of capitation funding, and in relation to individual doctors, who may also receive per capita reimbursement and be subject to bonuses, penalties and various forms of financial risksharing.
Techniques for managing clinical activity include: utilisation review (prospective, current and retrospective; mandatory second opinions and peer review); physician and hospital profiling; the development of disease management strategies involving the use of audit and guidelines; drug formularies; and education strategies aimed at clinicians.
Patient focused approaches seek to influence patients behaviour, so that they too make efficient use of scarce resources.These techniques include efforts to gain acceptance for primary care gatekeeping, case management, the promotion of watchful waiting, primary prevention and self care.
Chapter 2 starts with a general discussion of the aims of a systematic review of the US evidence, because methods of systematic review are still a relatively new development within health services research.This shows how systematic reviews bring a scientific rigour to the enterprise of literature review and increase the reliability and validity of conclusions.Chapter 2 specifies two research questions, the first to consider overall performance of managed care in the USA and the second to evaluate what is known about the effectiveness of particular managed care techniques.
Chapter 3 presents the results of the systematic review of US evidence on managed care.This is followed by a section in which the authors provide a brief discussion of their style of summarising the literature and of the overall strength of the research evidence.Finally, the results of the systematic review are organised according to six main dimensions of performance, namely utilisation, expenditures, prevention and health promotion, quality of care, consumers satisfaction and equity of treatment.At the end of the chapter, the authors summarise their findings by drawing the multiple dimensions of performance together for an integrated view of managed care's effectiveness as reported in the high-quality literature.The authors find generally lower hospital utilisation, higher rates of preventive care and comparable levels of quality of conventional US medical care.However, patient satisfaction is lower under managed care.Further, there are some important dimensions of performance where the data are inconclusive.
Chapter 4 focuses on the financial incentives and techniques used by managed care organisations to create an efficient system of health services.The techniques examined are utilisation review, profiling and disease management and clinical guidelines.
Chapter 5 discusses the application of managed care techniques in the UK through the development of the total purchasing (TP) pilot projects and considers the lessons to be learned from the US experience.Total purchasing is an experimental extension of general practitioner (GP) fundholding (GPFH) through which designated GP practices receive budgets to purchase potentially all of the services received by their patients.Finally, the chapter considers the current and potential use of US-style managed care techniques by the total purchasing projects; in particular it examines the role of financial incentives, utilisation review and management, medical practice profiling and disease management.
In the final chapter the authors reflect upon their analysis of the US evidence and its relevance for the UK.They point out that, although drawing lessons from abroad is a fashionable activity, it is also a hazardous one.Different histories, cultures and socio-economic institutions make the export of ideas and evidence problematic.Nonetheless, the authors point to various US evidence based themes-concerning organisational impact, targeted programmes and consistency of practice styles-that are of relevance to the application of managed care in the NHS.The authors recommend that the evidence from abroad be taken as a springboard for developing health services in the NHS and that the UK-style managed care be evaluated in its own cultural context.
The book is well referenced and is almost certainly the most comprehensive review of the managed health care currently available.It provides an invaluable data source for anyone seeking hard evidence on the achievements of managed care: that is anyone who is interested in the reality rather than the rhetoric.I would recommend this book to health managers, health politicians and administrators, medical doctors, health economists, public health professionals, students and those who are interested in comparing alternative methods of controlling the cost of the care.This book provides lots of useful information to help them to judge what might be in a given political, economics and cultural context the most adequate one.
Given that the focus of the book is on evaluating and comparing the US and the UK experiences the book will be of most use to those working in a similar context.