1 |
Basic properties of models for the spread of HIV/AIDSLutambi, Angelina Mageni 03 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: While research and population surveys in HIV/AIDS are well established in
developed countries, Sub-Saharan Africa is still experiencing scarce HIV/AIDS
information. Hence it depends on results obtained from models. Due to this
dependence, it is important to understand the strengths and limitations of
these models very well.
In this study, a simple mathematical model is formulated and then extended
to incorporate various features such as stages of HIV development, time delay
in AIDS death occurrence, and risk groups. The analysis is neither purely
mathematical nor does it concentrate on data but it is rather an exploratory
approach, in which both mathematical methods and numerical simulations
are used.
It was found that the presence of stages leads to higher prevalence levels in
a short term with an implication that the primary stage is the driver of the
disease. Furthermore, it was found that time delay changed the mortality
curves considerably, but it had less effect on the proportion of infectives. It
was also shown that the characteristic behaviour of curves valid for most
epidemics, namely that there is an initial increase, then a peak, and then a decrease occurs as a function of time, is possible in HIV only if low risk
groups are present.
It is concluded that reasonable or quality predictions from mathematical
models are expected to require the inclusion of stages, risk groups, time
delay, and other related properties with reasonable parameter values. / AFRIKAANSE OPSOMMING: Terwyl navorsing en bevolkingsopnames oor MIV/VIGS in ontwikkelde lande
goed gevestig is, is daar in Afrika suid van die Sahara slegs beperkte inligting
oor MIV/VIGS beskikbaar. Derhalwe moet daar van modelle gebruik
gemaak word. Dit is weens hierdie feit noodsaaklik om die moontlikhede en
beperkings van modelle goed te verstaan.
In hierdie werk word ´n eenvoudige model voorgelˆe en dit word dan uitgebrei
deur insluiting van aspekte soos stadiums van MIV outwikkeling, tydvertraging
by VIGS-sterftes en risikogroepe in bevolkings. Die analise is beklemtoon
nie die wiskundage vorme nie en ook nie die data nie. Dit is eerder ´n
verkennende studie waarin beide wiskundige metodes en numeriese simula˙sie
behandel word.
Daar is bevind dat insluiting van stadiums op korttermyn tot ho¨er voorkoms
vlakke aanleiding gee. Die gevolgtrekking is dat die primˆere stadium die
siekte dryf. Verder is gevind dat die insluiting van tydvestraging wel die
kurwe van sterfbegevalle sterk be¨ınvloed, maar dit het min invloed op die
verhouding van aangestekte persone. Daar word getoon dat die kenmerkende
gedrag van die meeste epidemi¨e, naamlik `n aanvanklike styging, `n piek en dan `n afname, in die geval van VIGS slegs voorkom as die bevolking dele
bevat met lae risiko.
Die algehele gevolgtrekking word gemaak dat vir goeie vooruitskattings met
sinvolle parameters, op grond van wiskundige modelle, die insluiting van
stadiums, risikogroepe en vertragings benodig word.
|
2 |
Incidence of HIV infection in rural KwaZulu-Natal in the context of the epidemiology and impact of HIV/AIDS in South Africa.Gouws, Eleanor. January 2007 (has links)
South Africa has had one of the fastest growing HIV epidemics in the world and almost 30% of women attending public antenatal clinics (ANC) are currently infected with the virus. But as the epidemic is starting to level off and antiretroviral therapy (ART) is becoming increasingly available, few methods exist to determine the impact of ART or other interventions on the epidemic in South Africa. This thesis explores the epidemiology and dynamics of HIV infection and investigates the potential impact of ART. Methods Total and age-specific prevalence data are analysed in time and space and are used to investigate patterns of infection in men and women, urban and rural, and low and high risk populations. Dynamical models are developed to estimate incidence from age-specific prevalence and trends over time and are compared to laboratory-based estimates of recent HIV sero-conversion. Incidence is estimated in different populations in South Africa. A dynamical model is developed to estimate the impact of ART on the future course of the HIV epidemic. Results HIV prevalence varies geographically and by age, sex and race. The average female-tomale HIV prevalence ratio is 1.7 and prevalence peaks at an older age among men than women. The age at which prevalence peaks among women has increased from 23.0 to 26.5 years between 1995 and 2002. Four patterns of infection are identified: among pregnant women attending ANCs, among men and women in the general population, and among migrant workers. HIV incidence among ANC attendees peaked in the mid to late 1990s (at 6.6% per year nationally) with variation between provinces. Current estimates of HIV prevalence and incidence among the general population in South Africa (aged 15-49 year) are 18.8% and 2.4% per year, respectively. Age-specific incidence estimates from dynamical models and laboratory methods are in good agreement provided the window period for the laboratory method is increased. Over the next ten years the provision of ART could avert 1 to 1.5 million deaths depending on whether it is provided when the CD4 cell count falls to 200 or 350 cells/ul. By 2015 about 1.1 million people will be receiving ART but this will have little impact on the incidence of HIV and scaling up of prevention efforts remains urgent. Conclusions The thesis explores some of the determinants and patterns of HIV prevalence and incidence in South Africa in order to find better ways to manage the epidemic of HIV, monitor changes and evaluate progress in control efforts. In order to fight the epidemic we need to mobilize the best possible science in support of those people and communities affected by the epidemic. / Thesis (M.Med.)-University of KwaZulu-Natal, Durban, 2007.
|
3 |
"I'm not fragile like the new-age kids," aging positively and reducing risk among older adults with HIV/AIDS; a qualitative and quantitative explorationMcCullagh, Charlotte January 2022 (has links)
The proportion of HIV-positive people over the age of 50 is increasing rapidly in New York City. An estimated half of those living with HIV are over 50. While many are long-term survivors, reflecting the transformation of HIV from a life-threatening illness to a chronic disease—due to the advent of highly active antiretroviral therapy (HAART) in 1996—others are newly diagnosed or newly infected. However, relatively few studies have examined how older adults with HIV/AIDS are aging well, and whether these strategies are associated with a reduction in risk behaviors.
To address these gaps, paper one, using a basic qualitative research methodology and constructivist grounded theory analysis approach, had two related objectives: (1) to explore the lived experience of men over 50 with HIV/AIDS in New York City; (2) to examine the ways in which individuals have aged successfully. Based on the findings of the aforementioned paper, paper two and paper three, using the Research on Older Adults with HIV/AIDS (ROAH) data set, determined if loneliness predicted condomless sex in the past three months and chemsex (paper 2) and if loneliness predicted a reduced CD4 count and substance use in the past three months. Using the three-paper model, the following dissertation sheds new insight into how older adults age well with HIV/AIDS but finds that loneliness does not predict negative health and risk behaviors in this group. The dissertation does, however, highlight other avenues for research, policy and practice based on the results.
|
4 |
Moving Beyond the Individual: A Data-driven Approach to Assessing the Multi-level Determinants of HIV among Adolescent Girls and Young Women in Sub-Saharan AfricaReed, Domonique Montier January 2024 (has links)
Adolescent girls and young women (AGYW; aged 15-24 years) in sub-Saharan Africa, the epicenter of the global HIV epidemic, have carried the primary burden of new HIV infections in this area for almost 40 years. Research has prioritized characterizing the individual predictors of HIV infection among AGYW by creating risk assessment tools that identify high-risk sub-populations for targeted HIV prevention efforts. Despite substantial efforts, there remains a disproportionate disease burden among this vulnerable population, suggesting a need to identify and assess new intervention targets beyond the individual. The objective of this dissertation is to expand our understanding of the complex relationship between the multi-level drivers of HIV infection among AGYW using advanced data science and epidemiologic methods.
This dissertation is divided into six chapters, the first of which is an introduction to the dissertation. The second chapter is a scoping review of the extant HIV-related literature that has leveraged data integration methods to combine heterogeneous, multi-level data sources. Chapters 3, 4, and 5 are empirical aims. Chapter 3 describes the development of an integrated dataset that combines information from the Population-based HIV Impact Assessment (PHIA) project, the Population and Housing Census, and the Joint United Nations Programme on HIV/AIDS (UNAIDS) Policy Indicators platform. The resulting dataset captures data at the individual, interpersonal, community, and societal levels across five sub-Saharan African countries: Cameroon, Eswatini, Malawi, Rwanda, and Uganda. Chapter 4 uses the dataset described in Chapter 3 and presents the application of causal discovery algorithms to characterize and graphically depict the pathways among individual, interpersonal, community, and societal risk factors of HIV infection among AGYW to identify the potential underlying causal mechanisms supported by the data. Chapter 5 uses the results from Chapter 4 to assess the impact of increasing the proportion of AGYW who completed secondary education on HIV prevalence using parametric g-formula. This dissertation ends with Chapter 6, which summarizes the dissertation's results and situates the findings within the broader HIV prevention literature.
A brief description of the dissertation results follows. The scoping review describes the four types of data integration methods: record linkage, multiple frame methods, imputation-based methods, and modeling techniques. I identified five thematic uses of data integration in the literature that supported the included articles’ study objectives. Those themes included using data integration to 1) describe HIVrelated etiology and prognosis; 2) develop or operationalize an HIV-related databases; 3) characterize sociodemographic, behavioral, clinical, and care risk factors; 4) estimate the population size of key or hard-to-reach populations; and 5) estimate HIV prevalence for key populations or varying geographical units. Then, using one of the described integration techniques, multiple frame methods, I present the process of developing a multi-level and -country integrated dataset that combined data from the PHIA Project, the Population and Housing Census, and the UNAIDS Policy Indicators platform. Additionally, I described the population of AGYW included in this study, as well as the different interpersonal, community, and societal environments they reside in, across Cameroon, Eswatini, Malawi, Rwanda, and Uganda.
I then applied the PC causal discovery algorithm to that dataset to elucidate the interconnectedness between individual, interpersonal, community, and societal level risk factors on HIV status among AGYW across each of the countries and overall. Community-level HIV prevalence and interpersonal sexual relationship factors consistently had direct paths to AGYW's HIV status for almost all country analyses. Additionally, there were multiple individual-level factors that had direct paths to AGYW's HIV status, and most of those variables were related to sexual behavior (e.g., number of sexual partners in the last 12 months, age of sexual debut). Additionally, there were multiple indirect paths to HIV status identified across all levels of organization. My last empirical study used the findings from Malawi and applied the parametric g-formula, to assess the impact of three hypothetical scenarios that model how increasing the proportion of AGYW who completed secondary education impacts HIV prevalence. I found that increasing the proportion of AGYW who completed secondary education from about 31% to 100% is associated with about a 26% decreased odds of HIV. The findings highlight the importance of improving educational attainment among AGYW, which will impact their life trajectory, economic prosperity, and overall autonomy.
The findings from this dissertation improve the knowledge base informing prevention interventions, thereby advancing the development of interventions that go beyond the individual to reduce the burden of HIV among AGYW. Additionally, the methods used in this dissertation provide an illustrative example of a novel and intersectional approach to assessing the multi-level determinants of health that may expand the current epidemiologic research program.
|
5 |
The Impact of Accelerated ART Initiation on Adverse Outcomes and Viral Non-Suppression among People with HIV in Thailand: Empirical Evidence from an Observational Cohort StudySeekaew, Pich January 2024 (has links)
Aim 1. Accelerated antiretroviral therapy (ART) initiation, including starting ART on the day of HIV diagnosis, has emerged to be one of the approaches to improve ART uptake by shortening or removing some preparatory steps before ART initiation. By doing so, accelerated ART initiation is thought to remove some structural barriers associated with ART initiation process.
However, several concerns still need to be addressed, such as whether the expedited process would lead to adverse treatment outcomes after ART initiation. Searched strategy was developed using both MeSH and free text terms relevant to accelerated ART initiation (same-day, immediate, rapid). Exclusion criteria were studies that did not focus on HIV, did not involve HIV treatment, included individuals with HIV aged lower than 12, and contained non-human subjects. Additionally, we excluded articles that were case-reports, qualitative studies, systematic reviews, commentary, points of view, and conference presentations.
Four electronic databases (PubMed, Embase, Web of Science, MEDLINE) were used to identify relevant studies published in English between January 2015 and December 2023. Outcomes were retention, viral suppression, pre-ART screening procedures, preferred baseline antiretroviral regimens, additional baseline medications, and adverse events after ART initiation. Two independent researchers were involved in the study selection process. Of 5,455 studies retrieved, 25 studies were included in the review (Cohen’s kappa: 0.88). Six studies reported findings from randomized controlled trials conducted in Lesotho (n=2), Haiti (n=1), South Africa (n=3), and Kenya (n=1), with one study conducted in both South Africa and Keya; 19 studies were observational cohort study from Ethiopia (n=4), West Africa (n=1), Italy (n=2), the United States (n=3), South Africa (n=3), Kenya (n=1), Rwanda (n=1), Sub-Saharan African region (n=1), the United Kingdom (n=1), Turkey (n=1), and China (n=1).
The majority of the studies were conducted in urban areas (n=19). Of the 25 included studies, 19 had same-day ART initiation as the intervention or the exposure (three studies measured the time to ART initiation from the day of care engagement, and 16 studies measured it from the day of HIV diagnosis). There was heterogeneity in the pre-ART screening procedures, from relying on symptomatic screening and history assessment to using non-molecular rapid tests to help identify individuals with increased risk of clinical contraindications. Despite this, individuals with symptoms consistent with WHO stage 4 neurological diseases were not eligible for ART. Efavirenz-based ARV was the most regimen reported. The majority of PWH preferred to start ART within 7 days of HIV diagnosis or care engagement (range: 56.5%-86%). Our review suggested mixed results on retention in care and viral suppression after ART initiation, although many studies indicated potential benefits. Despite this, no study reported an association between clinical adverse events, including deaths, and accelerated ART initiation. Our review suggested that accelerated ART initiation can potentially increase ART uptake while not negatively impacting treatment outcomes in some settings. New tools in HIV treatment, such as safer drug regimens and injectable ART, may help improve PWH’s experience and reduce the burden associated with pill burden and frequent clinic visits.
Aim 2. Accelerated antiretroviral therapy (ART) initiation has been proposed to address some structural barriers associated with the ART initiation process and improve ART uptake. Despite this, there has yet to be a consensus on how this approach should be implemented, especially concerning the clinical readiness screening procedures. While emerging literature has reported the clinical safety of accelerated ART, limited data are reported from Thailand. Given the heterogeneity of clinical profiles of people with HIV (PWH) in different regions, past studies may not be generalizable to Thailand.
Additionally, as different screening procedures affect the time to ART initiation, we need to learn how these procedures impact treatment outcomes. Data were obtained from PWH from 10 ART facilities in six provinces (Chiang Rai, Chiang Mai, Chonburi, Ubon Ratchathani, Songkhla, and Bangkok) in Thailand between July 2017 and July 2019 and followed up until January 2021. All PWH registered in HIV care were included in the analysis, regardless of baseline clinical status. ART facilities were categorized into three models according to the hospital policy on pre-ART laboratory screening procedures: Model A did not consider any lab results at the initiation, Model B considered only CD4 count, and Model C considered other non-CD4 baseline laboratory results.
Log-Poisson regression was used to assess the impact of hospital policies on adverse outcomes (deaths, ART discontinuation, loss to follow-up) at months three, six, 12, 18, and 24 after care engagement. Logistic regression was used to examine the impact of hospital policies on viral non-suppression (VNS, HIV-1 RNA>50 copies/mL) at months six, 12, and 18 after ART initiation. Multilevel mixed model was used to account for potential clustering within each hospital policy. Of 10,926 PWH in the dataset, 9,695 (88.7%) were included in this study. Among these, 68% (6,571/9,695), 13% (1,236/9,695), and 19% (1,888/9,695) were in Models A, B, and C, respectively.
Both Models A and B had 2 ART facilities each, while Model C had 6 ART facilities. 54.2% (5,257/9,695) self-reported to be men who have sex with men, and the overall baseline median CD4 (IQR) was 168 (129-404) cells/mm3. Compared to Model A, the average risk ratio (95%CI) of adverse events at months three, six, 12, 18, and 24 for Model B was 1.14(1.08-1.20), 1.40(1.31-1.49), 1.19(1.10-1.27), 1.11(1.02-1.21), and 1.32(1.21-1.44), respectively, while it was 1.21(1.16-1.27), 1.76(1.67-1.85), 1.59(1.50-1.67), 1.81(1.71-1.90), and 1.98(1.88-2.10) for Model C, respectively. Of 9,695 PWH, 6,785 (70%) had a confirmed date of ART initiation; 37% (2,513/6,785), 34% (2,332/6,785), and 13% (851/6,785) PWH had information on viral load status at months six, 12, and 24 after ART initiation, respectively. Among these samples, compared to Model A, the average odds ratio (95%CI) of VNS for Model B at months six, 12, and 18 was 0.79(0.59-1.06), 1.06(0.71-1.55), and 1.47(0.49-3.58), respectively, while it was 1.01(0.77-1.32), 0.68(0.40-1.09), and 0.93(0.31-2.22) for Model C, respectively. ART facilities that considered CD4 or any other non-CD4 baseline laboratory results before starting ART had, on average, a higher likelihood of adverse outcomes after the initial care engagement visit and viral non-suppression after ART initiation than ART facilities that did not consider any baseline laboratory result.
Aim 3. Clinical screening and psychosocial readiness assessments prior to antiretroviral therapy (ART) initiation are imperative to ensure clinical safety and ART adherence among people with HIV (PWH). However, multiple preparation steps and long wait times associated with ART initiation can contribute to HIV care disengagement and low ART uptake. To address some of the barriers associated with lengthy assessment process, accelerated ART initiation, an approach to start ART on or near the day of HIV diagnosis, has been proposed. Despite this, concerns with the expedited preparation process remain, especially with the PWH’s readiness to have optimal HIV care adherence.
This study examined the impact of time to ART initiation on adverse outcomes after care engagement and viral non-suppression (VNS) after ART initiation among PWH in Thailand. Data were obtained from PWH from 10 ART facilities in 6 provinces (Chiang Rai, Chiang Mai, Chonburi, Ubon Ratchathani, Songkhla, and Bangkok) in Thailand between July 2017 and July 2019 and followed up until January 2021. PWH who tested negative for cryptococcal antigen test at baseline and had a confirmed date of ART initiation were included in the analysis and were categorized into three groups based on the time interval between care engagement (defined as the day that PWH first registered at an ART facility) and ART initiation: (1) same day (ART initiation upon the day of care engagement or same day), (2) 1-7 days, and (3) more than 7 days.
Log-Poisson regression was used to assess the impact of time to ART initiation on adverse outcomes (deaths, ART discontinuation, and loss to follow-up) at months three, six, 12, 18, and 14 after care engagement. Logistic regression was used to examine the impact of time to ART initiation on VNS (HIV-1 RNA>50 copies/mL) after ART initiation at months six, 12, and 18 after ART initiation. Age, population, hospital policy on pre-ART screening procedures, and baseline CD4 were adjusted in the final models. Of 10,926 PWH in the dataset, 5,528 (50.6%) had complete information on the date of care engagement, negative results for the cryptococcal antigen test, and the date of ART initiation. Among these, 44.23% (2,445/5,528), 38.69% (2,139/5,528), and 17.08% (944/5,528) started ART on the day of, 1-7 days from, and more than 7 days from HIV care engagement visit, respectively.
The median age (IQR) was 29 (24-36) and 61% (3,387/5,528) identified themselves as men who have sex with men. The baseline median CD4 (IQR) was 283 (162-412) cells/mm3. Compared to PWH who started ART on the day of HIV care engagement visit, the average risk ratio (RR) of adverse outcomes for those who started ART between 1-7 days at months three, six, 12, 18, and 24 was 0.73(0.60-0.89), 0.66(0.55-0.79), 0.74(0.63-0.86), 0.83(0.71-0.98), and 0.84(0.70-1.01), respectively, while it was 2.27(1.91-2.71), 2.16(1.85-2.52), 1.70(1.46-1.98), 1.93(1.65-2.25), and 2.83(2.44-3.30) for those who started ART more than 7 days, respectively. In the adjusted models, the associations from both groups became statistically non-significant, except for the more than 7 days at month 24 (adjusted RR:1.08; 95%CI:1.04-1.12). Of 5,528 PWH, 29% (1,616/55,28), 36% (1,967/5,528), and 14% (795/5,528) had information on viral load status at months six, 12, and 18 after ART initiation, respectively.
Among these individuals, time to ART initiation was determined to have no impact on VNS in both crude and adjusted models. Accelerated ART initiation has the potential to improve ART uptake while maintaining optimal adherence to HIV care. However, HIV programs should recognize and respond to the diversity of needs among PWH to minimize adverse outcomes following ART initiation.
|
6 |
Placing the dead :the spatial distribution and spread of HIV in a major South African city.Rama, Parbavati January 2005 (has links)
The aim of this study was to establish a new understanding of the epidemiology of HIV/AIDS at the municipal level, but at the same time upholding the anonymity of the HIV infected and AIDS sufferers. Innovative research techniques such as the use of GIS (geographic information systems) as a research tool contributed to disclosing the patterns of the HIV pandemic in the Nelson Mandela Metropole that were not obvious or visible before. GIS involved geographic maps that detect the spatial relationship between HIV prevalence rates and vectors that drive the pandemic.
|
7 |
Secondary HIV transmissions via newly diagnosed HIV positive men who have sex with men (MSM) in Shenzhen, China: a qualitative study. / 中國深圳新感染HIV的男男性行為者中HIV二代傳播問題的定性研究 / CUHK electronic theses & dissertations collection / Zhongguo Shenzhen xin gan ran HIV de nan nan xing xing wei zhe zhong HIV er dai chuan bo wen ti de ding xing yan jiuJanuary 2012 (has links)
介紹 / 愛滋病在中國男男性行為者中的流行持續增長,而新感染HIV的男男性行為者扮演著重要角色。本民族志研究採用了社會生態模式來探討與新感染HIV的男男性行為者中HIV二代傳播、心理健康、以及使用健康服務相關的問題。研究方法包括深入訪談、焦點小組訪談、非正式訪談和參與觀察。此外還採訪了志願者和醫護人員。資料分析採用主題內容分析法。 / 結果 / 在確診為HIV呈陽性後,大多數的男男性行為者經受過一定程度的心理及精神上的問題。與HIV相關的緊張性刺激影響著他們適應這個確診。HIV與一些重要的心理、社會和文化的條件呈現一種綜合流行。而大多數的男男性行為者通過自身的應變能力逐漸康復,其中一些人甚至體驗到某種程度的成長。人的應變能力是一種基於個人與環境互動的建構。 / 11名(占24.4%)HIV呈陽性的男男性行為者報告發生過無保護的肛交行為。基於性伴侶的不同類型,與無保護肛交行為相關的因素則有所不同。這些無保護的肛交行為往往同時伴隨著物質濫用、對風險的錯誤認識、以及消極的情緒或者心理和精神問題。阻礙無保護肛交行為發生的積極因素包括社會支援、自我保健、自我保護和志願服務。 / 自上而下的公共衛生服務傾向於控制和檢測而不是賦權于男男性行為人群,並且在很大程度上忽視了新感染HIV的男男性行為者的心理和精神健康、性健康、以及自我保健的能力。新感染HIV的男男性行為者的未滿足的需求已經被識別,且他們更願意到男男性行為人群的社區,尤其是感染者小組那裏去尋求服務和支援。但男男性行為人群的草根組織卻缺乏資金和技術的支持。 / 結論 / 新感染HIV的男男性行為者所遭遇的問題都植根於特定的個人際遇以及他們所生活的社會生態系統。是時候採取一種廣泛而綜合的“健康同志社區的觀點、促進自我保健的策略、以及具有文化敏感性和社會效能的措施來預防HIV的二代傳播以及促進新感染HIV的男男性行為者的社會福祉。人類行為的非線性的特徵要求愛滋病健康行為研究從強調生物行為的範式轉移到著重愛滋病的社會根源的範式中來。 / Introduction / Newly diagnosed HIV positive men who have sex with men (NHIVMSM) play an important role in accelerating the high HIV prevalence in China. This ethnographic study, employing a modified social ecological model integrating concepts of adaptation, cognition, affect and action, investigated the inter-related issues on secondary HIV transmission, mental health and services utilization in this population. Methodologies included in-depth interviews, focus groups, informal interviews and participant observations. Moreover, information was also obtained from volunteers and health care workers. Thematic content analysis was performed. / Results / Most respondents commonly experienced psychological or mental health problems (e.g. depressive symptoms and anxiety) after their HIV diagnosis. HIV stressors, such as constraints of being HIV positive, limited information and knowledge of HIV/AIDS, ART and its side effects, associated co-morbidities and significant costs in health care, appeared to shape their adaptation to the diagnosis. Moreover, a syndemic was apparent among NHIVMSM and some influential psycho-social and cultural conditions, such as adversities in their migrants’ life, social suffering as MSM, cultural trauma, stigma and discrimination. Most respondents drew on a range of personal resilience strategies and some respondents testified to have achieved post-traumatic growth. Resilience was presented within a person-situation interactional construct. / Eleven (24.4%) respondents reported practicing unprotected anal intercourse (UAI). Several respondents reported their UAI had occurred in the first few months after their diagnosis when they suffered considerably from uncertainty, perceived stigma and identity struggles. Factors associated with UAI were based on differing partner types, such as fear of losing partners in a context of non-serostatus disclosure in lovers or stable partners, tongzhi (gay) sauna setting and moral judgment in casual partners, and poor economic status in commercial partners. UAI usually happened simultaneously in context of substance use, risk misconceptions, encountering negative emotion or mental health problems. Positive factors against UAI included social support, self-care, self-protection and volunteerism. / The current top-down public health services tended to operate on control and surveillance instead of empowering MSM. This approach largely ignored psychological and mental health, sexual health and self-care capacities among NHIVMSM, whose unmet needs were identified as preferring to obtain services and support from MSM and/or PLWH communities. However, current MSM organizations lacked funding and technical support. Health care providers operated with suboptimal care protocols, training and technical support. Coordination and collaborations among health care institutes and MSM communities were relatively weak. Tailored participatory health care is warranted, such as volunteerism, greater involvement of PLWH, health navigators and building supportive environment and services. / Conclusions / The problems of psychological and mental health, risky sexual behavior (UAI) and health services utilization that NHIVMSM encountered resulted from interactions between personal experiences and the social ecological systems they inhabited. Recommendation drawn include adopting a comprehensive and inclusive “healthy MSM community“ approach and a strategy of facilitating self-care to carry out culturally sensitive and socially effective measures to prevent secondary HIV transmission and to promote wellbeing among NHIVMSM. An emerging theoretical implication is that the nonlinearity of human behaviour requires paradigm shifting from a bio-behavioural emphasis to the social origin of HIV/AIDS. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Li, Haochu. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 425-457). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese; appendixes includes Chinese. / Abstract (English) --- p.iv / Abstract (Chinese) --- p.vii / Acknowledgements --- p.ix / Table of Contents --- p.xi / List of Tables and Figures --- p.xv / Glossary --- p.xvi / Abbreviation --- p.xviii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.1.1 --- High HIV prevalence and incidence among MSM in China --- p.1 / Chapter 1.1.2 --- Social and cultural environment faced by HIV positive MSM --- p.3 / Chapter 1.2 --- Sexual risk and secondary HIV transmission among HIV positive (and newly diagnosed) MSM --- p.7 / Chapter 1.3 --- Psychological and mental health among HIV positive (and newly diagnosed) MSM --- p.10 / Chapter 1.4 --- Health service utilization among HIV positive (and newly diagnosed) MSM --- p.13 / Chapter 1.5 --- Exploring complexities of secondary HIV transmission through qualitative studies --- p.14 / Chapter 1.6 --- Theories, concepts and the research framework --- p.15 / Chapter 1.6.1 --- Conceptualization of adaptation in medical anthropology --- p.15 / Chapter 1.6.2 --- The social ecological model --- p.17 / Chapter 1.6.3 --- Cognitive adaptation and self-control --- p.19 / Chapter 1.6.4 --- Emotion and motivation are influential in health behaviour --- p.21 / Chapter 1.6.5 --- Action world and its role in health behaviour --- p.24 / Chapter 1.6.6 --- Social control/social order --- p.26 / Chapter 1.6.7 --- Stigma --- p.27 / Chapter 1.6.8 --- Identity control --- p.29 / Chapter 1.6.9 --- Research framework --- p.32 / Chapter 1.7 --- Goals, objectives and research questions --- p.34 / Chapter Chapter 2 --- Methodology --- p.38 / Chapter 2.1. --- Entrée into the field --- p.38 / Chapter 2.1.1 --- The start of the research --- p.38 / Chapter 2.1.2 --- Pilot work --- p.39 / Chapter 2.2 --- The participants --- p.43 / Chapter 2.3 --- Data collection --- p.50 / Chapter 2.4 --- Data analysis --- p.58 / Chapter 2.5 --- Rigour --- p.62 / Chapter 2.6 --- Reflexivity --- p.68 / Chapter 2.7 --- Ethical considerations --- p.75 / Chapter Chapter 3 --- Social circumstances and MSM communities in Shenzhen --- p.78 / Chapter 3.1 --- Population and economic circumstances --- p.78 / Chapter 3.2 --- Shifting political situation --- p.80 / Chapter 3.3 --- A migrant society --- p.87 / Chapter 3.4 --- Shenzhen Culture --- p.93 / Chapter 3.5 --- MSM community and tongzhi subculture --- p.98 / Chapter 3.6 --- The subgroup of HIV positive MSM --- p.113 / Chapter 3.7 --- Public health implications --- p.117 / Chapter Chapter 4 --- Health care system and services related to HIV case detection and follow up --- p.118 / Chapter 4.1 --- Formal health care system --- p.118 / Chapter 4.2 --- Health insurance --- p.125 / Chapter 4.3 --- “Four Free and One Care“ policy --- p.126 / Chapter 4.4 --- Informal health care --- p.127 / Chapter 4.5 --- Services related to HIV case detection and follow up --- p.131 / Chapter Chapter 5 --- Psychological and mental health --- p.142 / Chapter 5.1 --- Negative mental health outcomes --- p.142 / Chapter 5.1.1 --- Depressive symptoms --- p.142 / Chapter 5.1.2 --- Anxiety symptoms --- p.146 / Chapter 5.1.3 --- Factors associated with negative mental health outcome --- p.150 / Chapter 5.1.3.1 --- Individual factors --- p.150 / Chapter 5.1.3.2 --- Interpersonal factors --- p.157 / Chapter 5.1.3.3 --- Cultural factors in community and family --- p.160 / Chapter 5.1.3.4 --- Institutional and structural factors --- p.163 / Chapter 5.2 --- Positive mental health outcomes --- p.166 / Chapter 5.2.1 --- Integrating negative experiences and recovery --- p.166 / Chapter 5.2.2 --- Resources for recovery --- p.169 / Chapter 5.2.3 --- Back to normal functioning --- p.170 / Chapter 5.2.4 --- Post-traumatic growth --- p.172 / Chapter 5.2.5 --- Factors associated with positive mental health outcome --- p.175 / Chapter 5.2.5.1 --- Individual factors --- p.175 / Chapter 5.2.5.2 --- Interpersonal factor --- p.181 / Chapter 5.2.5.3 --- Community-related factors --- p.184 / Chapter 5.2.5.4 --- Institutional factors --- p.187 / Chapter 5.3 --- Public health concern of suicidal ideation --- p.190 / Chapter 5.4 --- Impacts of psychological and mental health --- p.194 / Chapter 5.5 --- Summary of psychological and mental health in a modified socio-ecological mode --- p.195 / Chapter 5.6 --- Discussion --- p.197 / Chapter 5.6.1 --- The emerging of a syndemic in HIV and some psycho-social and cultural conditions --- p.197 / Chapter 5.6.2 --- Powerful social and cultural factors associated with mental health --- p.200 / Chapter 5.6.3 --- Resilience among newly diagnosed HIV positive MSM --- p.208 / Chapter 5.6.4 --- Service implications --- p.213 / Chapter Chapter 6 --- Sexual risk --- p.221 / Chapter 6.1 --- Continued unprotected anal intercourse (UAI) after being diagnosed HIV positive --- p.221 / Chapter 6.2 --- Changes in practising UAI during the study period --- p.222 / Chapter 6.3 --- Factors associated with UAI with non-commercial sex partners --- p.224 / Chapter 6.3.1 --- Individual factors --- p.225 / Chapter 6.3.2 --- Interpersonal factors --- p.229 / Chapter 6.3.3 --- Community-based factors --- p.231 / Chapter 6.3.4 --- Institutional factors --- p.234 / Chapter 6.4 --- UAI with commercial sex partners --- p.235 / Chapter 6.5 --- Comparing factors associated with UAI among commercial and non-commercial partners --- p.238 / Chapter 6.6 --- Reduced risky behaviour after diagnosis --- p.239 / Chapter 6.7 --- Factors associated with condom use --- p.241 / Chapter 6.7.1 --- Individual factors --- p.241 / Chapter 6.7.2 --- Interpersonal factors --- p.246 / Chapter 6.7.3 --- Community factors --- p.248 / Chapter 6.8 --- Other special issues related to risky sexual behaviour --- p.250 / Chapter 6.9 --- Summary of sexual risk in a modified socio-ecological model --- p.261 / Chapter 6.10 --- Discussion --- p.263 / Chapter 6.10.1 --- Prevalence of UAI --- p.263 / Chapter 6.10.2 --- Partner types and UAI --- p.265 / Chapter 6.10.2.1 --- Fear of losing partners in a context of non-serostatus disclosure --- p.266 / Chapter 6.10.2.2 --- Anonymous sexual encounters and moral judgment --- p.267 / Chapter 6.10.2.3 --- Economic barriers --- p.270 / Chapter 6.10.2.4 --- Intrapersonal contexts --- p.271 / Chapter 6.10.3 --- Critical views on some practices --- p.274 / Chapter 6.10.4 --- Emerging positive experiences from Shenzhen --- p.276 / Chapter 6.10.5 --- Service implications --- p.279 / Chapter Chapter 7 --- Health service seeking --- p.285 / Chapter 7.1 --- Problems identified in health service seeking --- p.285 / Chapter 7.2 --- Processes of adaptation --- p.289 / Chapter 7.3 --- Negative factors associated with health service seeking --- p.296 / Chapter 7.3.1 --- Individual factors --- p.296 / Chapter 7.3.2 --- Interpersonal factors --- p.302 / Chapter 7.3.3 --- Community-based factors --- p.304 / Chapter 7.3.4 --- Health care institution-based factors --- p.309 / Chapter 7.4 --- Positive factors associated with health service seeking --- p.319 / Chapter 7.4.1 --- Individual factors --- p.319 / Chapter 7.4.2 --- Interpersonal factors --- p.321 / Chapter 7.4.3 --- Community-based factors --- p.325 / Chapter 7.4.4 --- Factors in the health care institutes--free services --- p.328 / Chapter 7.5 --- Summary of health service seeking in a modified socio-ecological model --- p.329 / Chapter 7.6 --- Discussion --- p.331 / Chapter 7.6.1 --- Problems in health care institutes --- p.331 / Chapter 7.6.1.1 --- The top-down approach -- controlling instead of community building --- p.331 / Chapter 7.6.1.2 --- Problems among health care providers --- p.335 / Chapter 7.6.2 --- Tailored participatory approach to health care and education for HIV positive MSM --- p.339 / Chapter 7.6.3 --- Necessity for developing MSM communities --- p.342 / Chapter 7.6.4 --- Service implications --- p.349 / Chapter Chapter 8 --- Discussion and implications --- p.355 / Chapter 8.1 --- The occurrences of UAI and its hidden meaning --- p.355 / Chapter 8.2 --- Informing the future HIV epidemic among MSM in Shenzhen --- p.357 / Chapter 8.3 --- Difficulties of controlling the HIV epidemic among MSM --- p.361 / Chapter 8.4 --- New HIV prevention approach --- p.368 / Chapter 8.5 --- Critiquing theories for recommended changes --- p.386 / Chapter 8.6 --- Limitations of the study --- p.400 / Chapter 8.7 --- Conclusion --- p.405 / Appendix I to IX --- p.409 / Bibliography --- p.425
|
8 |
Estimation and analysis of measures of disease for HIV infection in childbearing women using serial seroprevalence data.Sewpaul, Ronel. January 2011 (has links)
The prevalence and the incidence are two primary epidemiological parameters
in infectious disease modelling. The incidence is also closely related
to the force of infection or the hazard of infection in survival analysis
terms. The two measures carry the same information about a disease because
they measure the rate at which new infections occur. The disease
prevalence gives the proportion of infected individuals in the population at
a given time, while the incidence is the rate of new infections.
The thesis discusses methods for estimating HIV prevalence, incidence
rates and the force of infection, against age and time, using cross-sectional
seroprevalence data for pregnant women attending antenatal clinics. The
data was collected on women aged 12 to 47 in rural KwaZulu-Natal for each
of the years 2001 to 2006.
The generalized linear model for binomial response is used extensively.
First the logistic regression model is used to estimate annual HIV prevalence
by age. It was found that the estimated prevalence for each year
increases with age, to peaks of between 36% and 57% in the mid to late
twenties, before declining steadily toward the forties. Fitted prevalence for
2001 is lower than for the other years across all ages.
Several models for estimating the force of infection are discussed and applied.
The fitted force of infection rises with age to a peak of 0.074 at age
15, and then decreases toward higher ages. The force of infection measures
the potential risk of infection per individual per unit time. A proportional
hazards model of the age to infection is applied to the data, and shows that
additional variables such as partner’s age and the number of previous pregnancies
do have a significant effect on the infection hazard.
Studies for estimating incidence from multiple prevalence surveys are reviewed.
The relative inclusion rate (RIR), accounting for the fact that the
probability of inclusion in a prevalence sample depends on the individual’s
HIV status, and its role in incidence estimation is discussed as a possible
future approach of extending the current work. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.
|
9 |
Placing the dead :the spatial distribution and spread of HIV in a major South African city.Rama, Parbavati January 2005 (has links)
The aim of this study was to establish a new understanding of the epidemiology of HIV/AIDS at the municipal level, but at the same time upholding the anonymity of the HIV infected and AIDS sufferers. Innovative research techniques such as the use of GIS (geographic information systems) as a research tool contributed to disclosing the patterns of the HIV pandemic in the Nelson Mandela Metropole that were not obvious or visible before. GIS involved geographic maps that detect the spatial relationship between HIV prevalence rates and vectors that drive the pandemic.
|
10 |
The effects of an anger-expressive cognitive-behavioural intervention programme on HIV-seropositive patientsLamb, Torsten Rainer 16 August 2012 (has links)
D.Phil. / This thesis presents an intervention programme that aims to facilitate anger-expression and takes psychosocial and immunological variables into account. The present research argues that if the effects of the programme are validated, similar programmes may yield similar benefits for other participants in future intervention programmes in a South African context. The nature, course and effects of the HIV disease are described and include specific processes and mechanisms of influence in physical, mental and social terms. Biological processes that result from immunological deficiencies causing AIDS are analyzed and an explication of disease progression is offered. Psychological and social aspects related to immune-system deterioration carry implications for patients and influence their prognosis. The research was conducted in the context of a biopsychosocial conceptualization and was aimed at reducing levels of anger and helping establish recourses in the patients to manage infection and disease, as well as improve or at least retard decrements in immunological functioning. The goal of this intervention programme was to reduce levels of anger, anxiety, depression and social isolation. This would in turn increase the participant's personal sense of self-control, self-efficacy and self-esteem. Changes in these factors would help retard the overall HIV disease progression. An intervention programme was tailored to address the specific needs of HIV- infected patients. The group intervention was focused in such a way that relevant psychological, behavioural and social aspects were addressed. The programme borrowed and used aspects of different models and reformulated an intervention that would best address the specific needs of the participants. It was possible to isolate specific problems and focus the intervention on these specific areas, such as depression, anger, social isolation and hopelessness. For example, it was possible to take into account the participants' low self-efficacy and problems related to a lack of interpersonal coping skills and develop the participants' confidence and assertiveness (Antoni, 1991)
|
Page generated in 0.0865 seconds