DYNAMICS OF THE HIV EPIDEMICS AMONG INJECTING DRUG USERS AND FEMALE SEX WORKERS IN VIETNAM

Although injecting drug users (IDUs) and female sex workers (FSWs) carry a disproportionate burden of HIV in Vietnam, little is known about the dynamics of the HIV epidemic among these high-risk populations. This thesis involved a secondary data analysis of the ‘2009 HIV/STI Integrated Biological and Behavioral Surveillance’ (IBBS) study to identify the correlates of HIV among IDUs and FSWs in Vietnam. It also involved the creation and simulation of an Agent-based model (ABM) to characterize the dynamics of the HIV epidemics among IDUs and FSWs, and to explore the effects of different intervention strategies. Data collected from 3,038 male IDUs, 2,530 street-based sex workers (SSWs) and 2,768 venue-based sex workers (VSWs) from 10 provinces in Vietnam during 2009-2010 were analyzed using descriptive statistics, bivariate and multivariate logistic regression analyses. An ABM was constructed using key behavioral data from the IBBS study. Different intervention scenarios based upon different levels of behavioral change were then simulated and compared. The aggregated prevalence of HIV infection was 30.6% (n=930) among male IDUs, 10.6% (n=267) among SSWs and 6.7% (n=186) among VSWs. Lifetime needle sharing, duration of drug injection ≥ 5 years, and having regular sexual partners who injected drugs were associated with increased risk of HIV among IDUs. Independent correlates of HIV infection in multivariate analysis, regardless of sex work types, included lifetime injecting drug use, high self-perceived HIV risk, and age ≥ 25 years. Intervention scenarios of lowering needle sharing levels among those who injected drugs resulted in the largest reductions in HIV infection in all simulated populations and across various intervention scenarios of behavioral change. The majority of the reductions occurred when needle sharing levels declined from 50% to 40% and to 30%, respectively. The HIV epidemic in Vietnam requires targeted prevention interventions among populations at high-risk of HIV infection. Results from the thesis suggest drug injection-related risks play an important role in fueling the epidemic and thus underscore the need to strengthen HIV harm reduction services in Vietnam. The thesis demonstrates that the use of ABM well complements traditional epidemiologic regression-based analysis in providing important insights into the complex dynamics of the HIV epidemics among IDUs and FSWs

The risks and benefits of providing HIV services during the COVID-19 pandemic

INTRODUCTION: The COVID-19 pandemic has caused widespread disruptions including to health services. In the early response to the pandemic many countries restricted population movements and some health services were suspended or limited. In late 2020 and early 2021 some countries re-imposed restrictions. Health authorities need to balance the potential harms of additional SARS-CoV-2 transmission due to contacts associated with health services against the benefits of those services, including fewer new HIV infections and deaths. This paper examines these trade-offs for select HIV services. METHODS: We used four HIV simulation models (Goals, HIV Synthesis, Optima HIV and EMOD) to estimate the benefits of continuing HIV services in terms of fewer new HIV infections and deaths. We used three COVID-19 transmission models (Covasim, Cooper/Smith and a simple contact model) to estimate the additional deaths due to SARS-CoV-2 transmission among health workers and clients. We examined four HIV services: voluntary medical male circumcision, HIV diagnostic testing, viral load testing and programs to prevent mother-to-child transmission. We compared COVID-19 deaths in 2020 and 2021 with HIV deaths occurring now and over the next 50 years discounted to present value. The models were applied to countries with a range of HIV and COVID-19 epidemics. RESULTS: Maintaining these HIV services could lead to additional COVID-19 deaths of 0.002 to 0.15 per 10,000 clients. HIV-related deaths averted are estimated to be much larger, 19-146 discounted deaths per 10,000 clients. DISCUSSION: While there is some additional short-term risk of SARS-CoV-2 transmission associated with providing HIV services, the risk of additional COVID-19 deaths is at least 100 times less than the HIV deaths averted by those services. Ministries of Health need to take into account many factors in deciding when and how to offer essential health services during the COVID-19 pandemic. This work shows that the benefits of continuing key HIV services are far larger than the risks of additional SARS-CoV-2 transmission

Audit of Antenatal Testing of Sexually Transmissible Infections and Blood Borne Viruses at Western Australian Hospitals

In August 2007, the Western Australian Department of Health (DOH) released updated recommendations for testing of sexually transmissible infections (STI) and blood-borne viruses (BBV) in antenates. Prior to this, the Royal Australian & New Zealand College of Obstetricians & Gynaecologists (RANZCOG) antenatal testing recommendations had been accepted practice in most antenatal settings. The RANZCOG recommends that testing for HIV, syphilis, hepatitis B and C be offered at the first antenatal visit. The DOH recommends that in addition, chlamydia testing be offered. We conducted a baseline audit of antenatal STI/BBV testing in women who delivered at selected public hospitals before the DOH recommendations. We examined the medical records of 200 women who had delivered before 1st July 2007 from each of the sevenWAhospitals included in the audit. STI and BBV testing information and demographic data were collected. Of the 1,409 women included, 1,205 (86%) were non-Aboriginal and 200 (14%) were Aboriginal. High proportions of women had been tested for HIV (76%), syphilis (86%), hepatitis C (87%) and hepatitis B (88%). Overall, 72% of women had undergone STI/BBV testing in accordance with RANZCOG recommendations. However, chlamydia testing was evident in only 18% of records. STI/BBV prevalence ranged from 3.9% (CI 1.5– 6.3%) for chlamydia, to 1.7% (CI 1–2.4%) for hepatitis C, 0.7% (CI 0.3–1.2) for hepatitis B and 0.6% (CI 0.2–1) for syphilis. Prior to the DOH recommendations, nearly three-quarters of antenates had undergone STI/BBV testing in accordance with RANZCOG recommendations, but less than one fifth had been tested for chlamydia. The DOH recommendations will be further promoted with the assistance of hospitals and other stakeholders. A future audit will be conducted to determine the proportion of women tested according to the DOH recommendations. The hand book from this conference is available for download Published in 2008 by the Australasian Society for HIV Medicine Inc © Australasian Society for HIV Medicine Inc 2008 ISBN: 978-1-920773-59-

Clinical care of HIV-patients: evaluating progress and future challenges

Since the introduction of combination therapy in 1996, Human Immunodeficiency Virus (HIV) treatment has changed substantially. Over twenty new antiretroviral drugs have been licensed for the treatment of HIV-infection and HIV has been transformed into a long-term chronic infection for many patients. Yet it remains unclear how improved efficacy of new antiretrovirals reported in clinical trials has translated to population-level effectiveness in general clinical care. Nor is it clear how the increasingly chronic nature of HIV-infection, characterised by an ageing HIV-population increasingly suffering from age-related non-infectious co-morbidities and drug-drug interactions, will affect HIV care. Such an evaluation is important not just to measure progress, but also to address future challenges for clinical care in order to develop evidence-based changes to clinical guidelines and ensure continued high-quality care. By analysing a dataset that collects data from all HIV-infected patients in clinical care in the Netherlands it was shown that the use of combination antiretroviral therapy (cART) regimens in the Netherlands closely follows changes in guidelines, to the benefit of patients. While there was no significant improvement in mortality, newer drugs with better tolerability and simpler dosing resulted in improved immunological and virological recovery and reduced incidence of switching due to toxicity and virological failure. An individual-based model of the ageing HIV-population in the Netherlands was constructed and used to quantify and evaluate the future challenges posed by an ageing HIV-population. The model showed that the age-structure of HIV-patients in the Netherlands is rapidly shifting to older age. By 2030, almost three quarters of patients will be aged 50 or over. This will result in an increased burden of co-morbidity, polypharmacy and an increasing proportion of patients who will experience potential complications with their HIV-treatment. Cardiovascular disease (CVD) in particular will become a major burden of co-morbid disease. Integrating a smoking cessation programme or changing HIV-treatment guidelines to recommend prescribing a polypill for CVD to all HIV-patients aged 45 or 55 years and over could improve the burden of CVD, improve patient outcome and be cost saving in the long-term.Open Acces

The Relationship Between Poverty and HIV/AIDS in Rural Thailand

HIV/AIDS is a global pandemic with critical demographic, economic, and social implications. The pandemic is widespread in poor regions of the world, including Southeast Asia where its long-term effects are potentially catastrophic. Despite the major impacts of the epidemic being already felt at the household level in many countries, a lack of recognition of the socioeconomic determinants of HIV infection and the economic and social impacts of HIV/AIDS and their relationship with poverty persists. This is due in part to the lack of systematic studies at the household, community, sectoral, and macro levels. The thesis describes a 'vicious circle' between HIV/AIDS, poverty and high-risk behaviour at the individual level. In the poverty-HIV/AIDS cycle, HIV-infected individuals are especially vulnerable to poverty, the poor are more likely to engage in high-risk behaviour such as commercial sex work, and high-risk behaviour in turn makes people susceptible to HIV infection. The thesis examines whether rural Northeast Thailand exhibits characteristics that support the existence of such a cycle. Four key relationships are considered and tested: (i) the relationship between previous HIV infection and current wealth or poverty; (ii) the relationship betweem wealth or poverty and HIV/AIDS knowledge; (iii) the relationship between previous wealth or poverty and current HIV infection; and (iv) the relationship between previous migration and current HIV infection. All four relationships are shown to hold using survey data from Khon Kaen province in Northeast Thailand. Poverty is shown to increase susceptibility to HIV infection, and HIV/AIDS is shown to reduce wealth and hence increase poverty. Under the circumstances, the hypothesis that rural Northeast Thailand exhibits characteristics that would suggest the existence of a poverty-HIV/AIDS cycle cannot be rejected. This thesis also provides several key contributions to the literature on HIV/AIDS and poverty. First, it provides quantitative and qualitative empirical analysis of the impacts of HIV/AIDS on households in a moderately affected region of Thailand. Second, it provides empirical analysis both on whether wealth and poverty affect the risk of HIV infection, and whether HIV infection affects wealth and poverty. The results from this thesis also provide significant empirical evidence of the importance of rural-urban migration in the spread of HIV in Asia. Finally, the thesis investigates the potential effects on the poverty-HIV/AIDS cycle of an ongoing socio-economic intervention, namely breaking the poverty-HIV/AIDS cycle via intensive rural development

Documentation of HIV prevention research and programmatic learnings from India—Selected peer-reviewed journal publications from the Knowledge Network Project (Volume 1)

Over the past decade (2000–11), India has achieved dramatic successes in reversing the HIV epidemic. These successes are largely due to the implementation of upscaled HIV-prevention interventions by the National AIDS Control Organization, two other donors, and nongovernmental organizations, under the National AIDS Control Program III. As the epidemic in India is concentrated in vulnerable subpopulations, these interventions were focused on high-risk groups. It is important to understand the lessons learned from the implementation of HIV-prevention programs and the vulnerabilities that need to be addressed to reach the goal of zero new infections. To support this understanding, the Population Council and its Knowledge Network Project partners have been documenting and disseminating evidence-based lessons from upscaled HIV-prevention programs in India. As part of this initiative, selected peer-reviewed journal publications from the Knowledge Network Project have been compiled into “Documentation of HIV Prevention Research and Programmatic Learnings from India,” Volume 1. This reference tool can help guide policymakers, program managers, and field teams in different states of India in the design and implementation of HIV-prevention programs

Design and Analysis of Infectious Disease Studies

[no abstract available

A modified mathematical model for HIV transmission, AIDS and intervention strategies in Ireland

The aim of this project was to modify transmission models previously developed to describe HIV transmission in Ireland through more precise estimates of parameters delineating sexual and needle sharing behaviour and AIDS related mortality, with a view to examining the extent of spread from IVDUs to the general heterosexual population. To provide predictions on HIV transmission and AIDS cases up to the year 2010 and to examine the sensitivity of the predictions to changes in the key parameters under different assumptions on intervention strategies. Essential data of relevance to HIV transmission were acquired (through the cooperation of the Department of Health, the AIDS Resource Centre, the Drug Treatment Centre, the Ana Liffey Drug Project, and St James’s Hospital, Dublin) and analysed. The parameters obtained from the descriptive and survival analyses were used in a refined deterministic model of HIV transmission which was solved numerically. An attempt at a solution using perturbation methods was undertaken. Results provided a plausible range of projected new HIV infections and AIDS cases up to the year 2010. The model projects that if present behaviour continues, approximately 1009 new infections may be expected in Dublin by the year 2000, and 1496 new infections by 2010. Small changes in the values of key parameters induce significant changes in projected trends, particularly in the longer term. However all projections point to the fact that •Non-IVDU women are particularly susceptible to HIV infection •Early introduction of behaviour change makes a significant difference to the growth of the epidemic •Expanding the Drug Treatment System could help to significantly reduce the spread of HIV •Central collation of data is essential if rational implementation of intervention plans is to be achieve