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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.

HIV transmission pattern among men who have sex with men in Shenzhen. / CUHK electronic theses & dissertations collection

January 2010 (has links)
Background A dramatic increasing trend of HIV prevalence among men who have sex with men (MSM) was observed in China from 2000. Most previous investigations were based on convenience sampling and none of them differentiated money boys (MB) from other MSMs. The objectives of this study was to determine the prevalence of HIV infection and its risk factors among MSMs in Shenzhen, China, using approximate probability sampling methods; and to interpret HIV transmission pattern among MSMs with both phylogenetical and epidemiological information. / Conclusions The prevalence of MV infection in Shenzhen MSMs was similar to the national rate in MSMs. HIV infection and related characteristics in Mf3s and other MSMs were different, indicating that a separate analysis was necessary. TLS could provide information on venue comparisons for venue-based MSMs and RDS could recruit more hidden subjects. Results from this study suggest that venue-specific intervention approaches should be developed and provided to different venues. / Results HIV prevalence was 5.5% among MSMs in Shenzhen. A significantly lower HIV infection was observed in MBs (4.5%) compared with other MSMs (7.0%). The HIV infection rate among MSMs was 5.7% by TLS and 4.6% by RDS, which were not significantly different. Factors related to HIV infection in MSMs included syphilis infection, occupation, sexual orientation, venue for recruitment and hometown HIV prevalence. HIV rate and social-behavioral characteristics were found to vary with venues, with significantly higher rates in family clubs, parks and saunas, than entertainment venue. Molecular phylogenetical analysis showed that genetic clusters were related to receptive anal intercourse, short stay in Shenzhen, early age of first sex, and high hometown HIV prevalence. Venue-specific transmission chains were observed in 60% of the subjects. / Subjects and Methods A total of 2143 MSMs were recruited in Shenzhen from 2008 to 2009, including 1651 persons from time-location sampling (TLS) and 492 from respondent-driven sampling (RDS). A separate recruitment of MBs and other MSMs was applied in TLS surveys and a mixed sample of MSMs was applied in RDS. All subjects were interviewed and had blood tests for HIV and syphilis. HIV positive samples were further used for phylogenetic analysis. / Zhao, Jin / Adviser: Mingliang He. / Source: Dissertation Abstracts International, Volume: 73-02, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 161-177). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

HIV related sexual risk behaviors among men who have sex with men in China: a cohort and randomized controlled study. / 中國男男性接觸者高危性行為的前瞻性隊列及臨床對照試驗研究 / CUHK electronic theses & dissertations collection / Zhongguo nan nan xing jie chu zhe gao wei xing xing wei de qian zhan xing dui lie ji lin chuang dui zhao shi yan yan jiu

January 2011 (has links)
Discussion. The epidemic of HIV/STD among MSM is severe, and the prevalence of risk sexual behaviors was at a high level among MSM in China. The risk factors for HIV/STD and factors associated with DAI reported in this study give some insights towards designing relevant prevention programs. The simplicity and feasibility of our effective intervention, enhanced VCT, makes it possible for this to be incorporated into standard VCT procedures. Further translational research is needed to investigate its effectiveness in the real-world setting. / Introduction. Men who have sex with men (MSM) have become the main group for HIV transmission in China in 2009. There have been many epidemiological cross-sectional studies targeting MSM in China in recent years. These provide limited data compared with cohort studies, which can describe the rate at which HIV/STD are spreading in a target population. Moreover, there is a dearth of intervention studies which are theory-based with rigorous research methodology in China. Last but not least, research is needed on sexual behaviors and their determinants, including cognitions from health behavioral theories, event-specific factors, etc. / Objectives. This study investigated the prevalence and incidence of HIV/STD, as well as their associated risk factors among MSM in Nanjing, China. It also explored the prevalence of unprotected anal sex (UAI) and the associated factors, including cognitions from health behavioral theories and event-specific factors. In addition, this is also one of the first studies to examine the efficacy of a randomized control trial (RCT) designed intervention, to use enhanced voluntary counseling and testing (VCT) to reduce UAI among MSM in China. / Results. The RDS-adjusted HIV, syphilis and HCV prevalence were respectively 7.3%, 14.4% and 0.2% at baseline. Of the 397 MSM who were found to be HIV seronegative at baseline, 286 (72.0%) retested at Month 6. HIV, syphilis and HCV incidence were respectively 5.12, 7.58 and 0 per 100 person-years (PY). Recruiting male sex partners mostly at saunas was the risk factor associated with being HIV seropositive at baseline (OR=3.84) and undergoing HIV/syphilis seroconversion at Month 6 (RR=2.351RR=6.72). In the RCT study, participants in the Intervention Group reported significantly less risk than those in the Control Group (UAI with any male sex partners: 48.4% vs. 66.7%;UAI with regular male sex partners: 52.2% vs. 68.9%) at Month 6. Furthermore, Perceived Behavior Control showed a significant association with DAI with both regular (AOR=0.42) and casual partners (AOR=O.73). / Subjects and Methods. A cohort study and randomized control trial were conducted. Out of 416 MSM approached by respondent driven sampling (RDS), 397 HIV negative participants were recruited to the HIV/syphilis/HCV cohort, and they were invited to return for a follow-up visit at Month 6. A subsample from the baseline cohort consisting of 307 MSM, was randomly assigned to either the Intervention Group (enhanced VCT) or the Control Group (standard VCT). Evaluation was conducted at Month 6. Both baseline and Month 6 visits consisted of VCT service and interviewing. Statistical methods such as Chi-square test, logistic regression and Poisson regression were used in this study. / Hao, Chun. / Adviser: Joseph TF Lan. / Source: Dissertation Abstracts International, Volume: 73-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 166-179). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract and appendixes I-II also in Chinese.

The use of love medicine among black Africans in KwaZulu-Natal and risks of HIV transmission to both men and women in South Africa.

Kunene, Mirriam Busisiwe. January 2010 (has links)
No abstract available. / Thesis (Ph.D.)-University of KwaZulu-Natal, Durban, 2010.

A two-mode network approach in assessing and modelling HIV transmission patterns among men who have sex with men in Hong Kong / CUHK electronic theses & dissertations collection

January 2015 (has links)
In the past decade, the rising incidence of human immunodeficiency virus (HIV) in men who have sex with men (MSM) calls for targeted epidemiological investigations. However, the approach of most current epidemiological studies might be inadequate for characterising transmission risks of MSM, as they focus largely on the practice of risk behaviours in population context and have assumed a homogeneous distribution of such behaviours and their resultant risks in HIV transmission. A study investigating the networking pattern of MSM, in addition to their sexual behaviour, was therefore proposed to re-examine HIV epidemiology in Hong Kong and model HIV transmission dynamics. / Following literature review on network analyses conducted in MSM, it was found that the use of two-mode network data for constructing sexual affiliation network had not been widely applied. Such two-mode network approach could be more feasible in describing sexual structure of MSM, who are connected by their preferred social venues. To adopt this approach, a two-part study, composing a field survey and a modelling study, was performed. A cross-sectional questionnaire survey was conducted between January and April 2013 to obtain data about sex-networking venues and associated behavioural profiles of MSM in Hong Kong. Comparisons of networking patterns, risk behaviour and demographics between MSM in different networks, delineated by two-mode network analysis, were made. Based on the survey data and assumptions derived from other network-based and behavioural studies, HIV transmission dynamics was simulated by building a stochastic agent-based model. / In the field survey, a total of 932 respondents were recruited from physical venues (n=625), including nine bars and six saunas, and the Internet (n=307). The proportion of MSM using condom for every anal sex with casual partners met in physical venues was 66.6% (225/338), while that for partners met in the Internet was 62.6% (139/222). Only 51.5% (204/396) MSM always used condom while having anal sex with regular partners. Community detection by networks of social venues identified nine clusters of MSM from three network bases. The simulation model gave a median number of new HIV infections over a 5-year period at 83 per 1000 MSM. The median numbers of annual infections ranged between 14 and 20. In over 30% of MSM networked through the Internet, having regular sex partners or practising receptive anal sex, more than 50 infections out of 500 iterations could occur in the model simulation, suggesting their higher risk of HIV infection. / In conclusion, the modelling results suggested that HIV transmission in Hong Kong might have occurred largely between regular partners. The potential impact of local sex-networking pattern through social venues with casual partners on HIV transmission is relatively little and indirect. To prevent HIV from spreading into new networks, intervention shall be targeted at MSM having unprotected anal sex with regular partners and seeking casual partners in social venues, especially through the Internet. Network approach in HIV epidemiology, such as collection of network-based data from HIV-infected MSM as part of surveillance, and assessing the network configuration from time to time, shall also be considered. / 過去十年間,透過同性性行為感染愛滋病病毒的個案持續上升,令針對男男性接觸者的流行病學研究顯得重要。現時大部分相關研究都假設所涉行為和相應的傳染風險是平均分佈於研究人群中,採用這研究方法去了解男男性接觸者間的病毒傳播風險明顯有所不足。有鑑於此,本研究透過了解男男性接觸者的社交網絡模式及其風險行為,重新審視本地愛滋病病毒感染的流行病學狀況及設計相關模型,用以了解病毒的傳播及流行規律。 / 探討過往文獻發現,雖然二模網絡能勾劃出男男性接觸者與其結識性伴侶的社交場所間的關係,卻未被廣泛應用於流行病學研究。本研究採納二模網絡的分析方法,並分兩部分進行。實地調查部分於二零一三年一月至四月期間進行,透過問卷收集本港男男性接觸者結交性伴侶的場所及相關性行為等資料,並比較其網絡模式、風險行為及人口特徵。建模研究部分則是利用調查所得之數據及參考其他研究去建立模型,用以模擬愛滋病病毒的傳播規律。 / 問卷調查從九間酒吧、六間桑拿及互聯網中,招募了九百三十二位受訪者參與研究。受訪者中,每次肛交均使用安全套的比率因性伴侶的種類而異,比率介乎百分之五十二至六十七。透過分析三種社交場所的網絡結構,本港男男性接觸者社群共可分為九個群組。由模擬模型得知,五年間新增的愛滋病病毒感染個案為八十三宗(每千人計),而相應的年度感染數字則介乎十四至二十宗。從五百次模擬運算中,發現超過三成透過互聯網結識性伴侶或擁有固定性伴侶的男男性接觸者與及受體肛交者的感染次數多於五十次,顯示其較高的愛滋病病毒感染風險。 / 總括而言,研究發現本港愛滋病病毒的傳播多於固定性伴侶間發生。相反,透過本地社交場所結識非固定性伴侶的網絡模式只間接影響本港愛滋病病毒的散播。為有效預防愛滋病病毒散播,干預措施應針對有與固定伴侶進行不安全性行為及透過互聯網結識性伴侶的男男性接觸者,同時衛生部門亦可考慮將感染愛滋病病毒的男男性接觸者的網絡數據納入恆常監測及不時評估同志社群間的網絡結構。 / Poon, Chin Man. / Thesis Ph.D. Chinese University of Hong Kong 2015. / Includes bibliographical references (leaves 112-121). / Abstracts and appendix B also in Chinese. / Title from PDF title page (viewed on 07, October, 2016). / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only.

A retrospective analysis of prevention of mother to child transmission (PMTCT) outcomes in a group of infants attending paediatric practices in central Durban.

Cassim, Shakira Mahomed. January 2009 (has links)
The vast majority of paediatric HIV occurs in sub-Saharan Africa and could be averted through implementation of effective Prevention of Mother to Child Transmission (PMTCT) strategies. At the United Nations General Assembly Special Session on HIV/AIDS in 2001, members committed themselves to the goal of reducing paediatric HIV by 20% by 2005 and by 50% by 2010. In South Africa, rates of HIV infection range between 28% in KwaZulu-Natal and 16% in the Western Cape. The South African National Department of Health has, over the past few years, phased in a comprehensive package for PMTCT of HIV. KwaZulu-Natal implemented its programme in 2002. The South African private healthcare sector follows guidelines of those of developed countries for PMTCT. Not much data is available of the outcome of infants born to HIV positive mothers managed in private practice. In view of this, the present study aimed to assess success or otherwise of PMTCT in private paediatric practice in South Africa. Eight of the 20 private paediatricians, in the central region of Ethekweni Metro of KwaZulu-Natal (Durban Central Area), agreed to participate in a retrospective study. Data for all their HIV exposed infants between January 2004 and June 2005 were reviewed. One hundred and one Black African infants were born to 100 HIV positive women aged 29.85 years (SD 5.38; range 18-44 years). The median CD4 count was 426 (IQR 244-613). The median viral load at first presentation was 3.97 logs (IQR 1.6-5.8) or 11 391 copies/ml (IQR 2 013-41 502). Eighty six women had HAART, nine had other antiretroviral therapy and five had no prophylaxis. Treatment started before 34 weeks in 72 women. There were 93 caesarean sections. There were 20 low birth weight neonates, 18 were preterm and all had been formula fed and received AZT for six weeks. Of the 92 tested, two (one preterm) were positive. Although caesarean deliveries, both these mothers had not adhered to the optimal treatment protocol. Of the rest, eight did not return for HIV testing and one died (the only neonatal death). This death was unlikely to have been HIV related. The transmission rate of less than one percent in those women who followed the protocol optimally is much better than that in the SA public sector, and is consistent with transmission rates in the developed world. / Thesis (M. Med.)-University of KwaZulu-Natal, Durban, 2009.

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 jiu

January 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 --- Individual factors --- p.150 / Chapter --- Interpersonal factors --- p.157 / Chapter --- Cultural factors in community and family --- p.160 / Chapter --- 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 --- Individual factors --- p.175 / Chapter --- Interpersonal factor --- p.181 / Chapter --- Community-related factors --- p.184 / Chapter --- 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 --- Fear of losing partners in a context of non-serostatus disclosure --- p.266 / Chapter --- Anonymous sexual encounters and moral judgment --- p.267 / Chapter --- Economic barriers --- p.270 / Chapter --- 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 --- The top-down approach -- controlling instead of community building --- p.331 / Chapter --- 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

Pharmaco-immunological-virological dynamics in intrapartum HIV-1 transmission (PIVD study)

Singh, Michelle. January 2009 (has links)
Background: Multiple factors contribute to mother-to-child transmission (MTCT) of HIV-1, including virological, obstetric and biological factors. Other possible contributory determinants for high MTCT rates include immunological factors such as host genetics and viral genetic variations. Despite several therapeutic, prophylactic and obstetric interventions to reduce the proportion of infants infected during labour and delivery, mechanisms for intrapartum HIV-1 transmission remain elusive and current interventions, could, therefore remain sub-optimal. Much controversy has surrounded the correlation of HIV-1 RNA (viral load) in the systemic and genital compartments of women. The influence of short-term antiretroviral (ARV) drugs on genital tract HIV-1 is also unclear. At the time the present study was initiated, a regimen of maternal intrapartum and neonatal postpartum single-dose Nevirapine (sdNVP) was the standard of care for the prevention of mother-to-child transmission (PMTCT). In most low and middle-income countries, including South Africa, sdNVP has been documented as effective intrapartum HIV-1 prevention based on plasma pharmacokinetic levels, decreased viral loads (HIV-1 RNA) and reduced rates of intrapartum transmission, yet operational studies continue to report high intrapartum transmission rates despite the administration of sdNVP. As a result perinatal HIV-1 transmission remains a significant public health concern in several African countries. Aim: The primary aim of this study was to describe the pharmacological dynamics of Nevirapine in association with virological and immunological risk factors for intrapartum HIV-1 transmission in a South African PMTCT programme where sdNVP was the standard of care. Methods: Following regulatory approval from the Biomedical Research Ethics Committee at the University of KwaZulu-Natal (UKZN), one hundred and twenty pregnant HIV-infected women who received the sdNVP regimen for prevention of mother-to-child HIV-1 transmission were enrolled between April-December 2006 at King Edward VIII Hospital (KEH) in Durban. Blood and cervicovaginal lavage (CVL) samples were collected from women at pre-NVP (during pregnancy) and post-NVP dosing (during labour/delivery). In addition to infant blood sampling at birth (post-NVP), postnatal infants were assessed at four and six weeks postnatally. Pharmacological laboratory investigations involved measurement of NVP drug concentration by Tandem Mass spectrophotometry. Virological investigations comprised HIV-1 RNA (viral load) quantitation, HIV-1 drug resistance testing (HIV-1 transmitting women only) and HIV-1 DNA PCR testing (infants only). Immunological investigations were only undertaken in a selected case-control subset of HIV-1 transmitting women and their infants. In this component, laboratory investigations included the determination of CCL3 and CCL3-L1 gene copy numbers, identification of single nucleotide polymorphisms (SNP’s) and haplotype characterisation of the CCL3 gene. All women were also screened for the presence of sexually transmitted infections (STI’s) during pregnancy. Results: One hundred and twenty women were enrolled onto this study. Of these, 110 women delivered 117 live infants (103 singletons and 7 twin pairs). Twelve (10.9%) women transmitted HIV-1 to their infants, while 95 (86.0%) were classified as non-transmitters. As a result of seven twin deliveries, the infant cohort comprised of 117 infants in total. Following two separate DNA PCR tests, HIV-1 infection was identified in 14 (11.9%) of study infants while the remaining 90 (76.9%) were exposed-uninfected. HIV infection status remained unknown for 13 infants due to infant demise (1.7%), lost to follow-up (7.7%) or study withdrawal (1.7%). During active labour (sampling that was best representative of the intrapartum phase) and within 20 hours of dosing, the median NVP concentration of 1070 ng/ml in the maternal systemic compartment was almost 44 times higher than the NVP levels detected in the genital compartment [24.5 ng/ml] (p < 0.001). NVP drug levels were below the 100 ng/ml therapeutic target in seven (13.7%) of 51 plasma and in all 39 CVL samples. While no significant association was found between NVP concentration in the systemic compartment and HIV-1 transmission (p = 0.4), this association was statistically significant in the genital compartment(p = 0.02). The median plasma NVP level detected among infants at birth was 83 times above the IC50 WT (10 ng/ml) and eight times higher than the 100 ng/ml therapeutic target for NVP. More than 71.0% of the infants achieved NVP drug levels above the therapeutic target. In general, higher levels of HIV-1 RNA (viral load) were observed in maternal plasma when compared to CVL. Following intrapartum sdNVP dosing, reduction in HIV-1 RNA levels did occur, however R80.0% of the women experienced no change to their HIV-1 RNA levels in both systemic and genital compartments during active labour. These findings were further supported by the strong correlation observed when comparing pre and post-NVP HIV-1 RNA levels in both maternal systemic [r = 0.81, p < 0.0001] and genital compartments [r = 0.80, p < 0.0001] during active labour. HIV-1 transmitting women had significantly higher viral loads than their non-transmitting counterparts in systemic and genital compartments, before and after intrapartum sdNVP administration. In terms of perinatal transmission this observation was only statistically significant for plasma (p = 0.02) and not CVL (p = 0.7). Maternal viral load was inversely correlated with maternal CD4 cell counts in both systemic and genital compartments. Almost 40.0% of women in this study had at least one type of STI detected during pregnancy. Maternal STI’s were detected in four (66.6%) intrapartum transmitting women and in 38 (38.8%) of non-transmitting women. No significant association was observed between the presence of maternal STI’s and the risk for intrapartum MTCT (p = 0.2,RR: 2.90, 95% CI: 0.60-15.40). The presence of maternal STI’s was associated with higher median viral loads in both systemic and genital compartments of all women, independent of intrapartum HIV-1 transmission. Despite trial-like conditions and optimal sdNVP dosing, the overall MTCT rate in this exclusively formula-fed cohort was 11.9%, of which 50.0% were in utero and 50.0% were intrapartum HIV-1 transmissions. In utero and intrapartum MTCT rates were 5.9% and 5.9% respectively. Discussion/Conclusion: Detectable CVL HIV-1 RNA that correlated well with plasma HIV-1 RNA, in conjunction with sub-optimal NVP drug concentration in maternal CVL during active labour, suggests that intrapartum HIV-1 infected women continue to act as reservoirs for both vertical and horizontal HIV-1 transmission throughout the duration of pregnancy. These findings confirm that the role of sdNVP in PMTCT was primarily one of infant prophylaxis. This was further supported by relatively unchanged maternal HIV-1 RNA (viral load) during active labour, in both systemic and genital compartments. Early identification of women who need highly active antiretroviral therapy (HAART), and initiation of such therapy as early as possible during pregnancy, not only benefits maternal health but remains the best prophylaxis against mother-to-child HIV-1 transmission. Universal access to HAART and improving strategies to optimize coverage of the current dual ARV regimen sdNVP and Zidovudine for PMTCT remain urgent research priorities in several resource-limited settings. Ongoing STI counseling, intensive screening/testing of women and their partners together promotion of condom usage, safer sex practices and aggressive STI treatment are simple interventions with tremendous impact for PMTCT in resource-limited settings. / Thesis (Ph.D.)-University of KwaZulu-Natal, Durban, 2009.

Implementation of the dual therapy prevention of mother-to-child transmission protocol

Singh, Vikesh January 2010 (has links)
Antiretroviral drugs taken during pregnancy, reduce the rates of mother-to-child transmission from 35 percent to as low as 1 to 2 percent (UNAIDS, 2009). In 2002, the Prevention of Mother-to-Child Transmission (PMTCT) programme was implemented in South Africa. Studies on the implementation of the PMTCT programme have shown that understaffed and under-developed health care facilities were key barriers to the provision of PMTCT services (Health Systems Trust, 2002: 6; Skinner et al., 2003). The aim of this study was to assess the challenges experienced by health care workers working in public sector facilities in the Nelson Mandela Metropole after implementation of the dual therapy PMTCT programme. Four areas were investigated: Infrastructure; Drug Supply Management; Clinic Procedures and Staffing. A quantitative descriptive study was conducted in August 2009 at nine public health care facilities in the Nelson Mandela Metropole, South Africa. Questionnaires were issued to 81 nurses and 41 pharmacy personnel (pharmacists and pharmacist assistants). Checklist audit forms were issued to the Facility Manager of each facility and completed with the researcher. The key findings for Infrastructure were lack of space at patient waiting rooms (9; 100 percent n=9), counselling area (5; 55.5 percent; n=9), nurse consultation rooms (6; 66.6 percent; n=9), storage areas (5; 55.5 percent; n=9) and filing areas (7; 77.7 percent; n=9). The key findings for Drug Supply Management were none of the dispensaries (0 percent; n=10) were fully compliant with Good Pharmacy Practice, pharmacy personnel indicated that there were no stock cards for medication (13; 31.7 percent; n=41); there was less than two weeks supply of buffer stock kept for zidovudine and nevirapine (13; 35.1percent; n=37) and medication orders were placed without any reference to minimum and maximum levels of medication (15; 36.5 percent; n=41) . The key findings for Clinic Procedures were only two facilities followed up on patients that had missed appointments (22.2 percent; n=9) and four facilities (44.4 percent; n=9) had a tracking system for patients that had defaulted. Of the nine facilities only three (33.3 percent; n=9) updated patient demographic details regularly. The key findings for Staffing were a shortage of doctors, nurses, counsellors and pharmacists at the facilities. One of the major challenges identified was the lack of training offered on new PMTCT protocols with 56.2 percent (45; n=80) of the nurses stating that no training was provided on the dual PMTCT protocol. Only 54.3 percent (44; n=81) of nurses stated that they knew the criteria to start the mother on dual PMTCT therapy. In conclusion there is an urgent need for barriers such as lack of staff, lack of space, lack of training on PMTCT and standard procedures for follow up of patients to be addressed in order to ensure the successful scaling up of PMTCT.

The Association between Social Network Characteristics and HIV Testing Behavior among Users of Illicit Drugs

Gordon, Kirsha S. January 2017 (has links)
INTRODUCTION: Human Immunodeficiency Virus (HIV) infection remains prevalent among the minority and drug using population in the United States. Testing for HIV is an important and cost effective way to reduce HIV prevalence. OBJECTIVE: To assess the HIV testing behavior of people who use non-injected drugs (PWND) and compare it to that of people who use injected drugs (PWID), in order to determine which factors, in terms of social context as well as individual risks, predict HIV testing among the PWND. METHOD: A cross-sectional study of HIV testing behavior of PWND compared to PWID was conducted and the data was analyzed by applying negative binomial regression models. Then, a negative binomial regression using generalized estimating equation (GEE) was employed in order to identify the predictive factors for HIV testing among PWND over a 2-year period. RESULTS: Individuals who reported using injected drugs tended to undergo HIV tests more often compared to those who used non-injected drugs, PR (95% CI) = 1.24 (1.02, 1.51), p = 0.03. The interaction term between injection status and emotional support in relation to HIV testing was significant, 0.75 (0.59, 0.97), p = 0.03. PWID that had access to greater emotional support on average tended to test for HIV less frequently than did PWID with less emotional support. In stratified analyses, emotional support was negatively associated with testing among PWID and positively associated among PWND, though both relationships were borderline significant. HIV testing among users of illicit drugs was dependent on emotional support. According to the GEE models examining the factors predicting HIV testing among PWND, sexually transmitted infections, non-injected heroin use, being in drug treatment, engagement in sexual transactions, and instability in drug networks were the main factors contributing to being HIV tested, as well as frequency of testing. The positive influence of emotional support on these variables was borderline significant. CONCLUSION: People who use non-injected drugs are less likely to test for HIV compared to those who use injected drugs, though they may share similar risk factors for HIV transmission and acquisition. To exert a greater impact on the HIV epidemic, interventions and policies encouraging HIV testing in this subpopulation, which remains under-recognized by both researchers and health practitioners in terms of the potential risks for contracting the HIV, are warranted.

Population-level HIV risk and combination implementation of HIV services

Philip, Neena M. January 2020 (has links)
Background: HIV transmission is greatly reduced when antiretroviral treatment (ART) suppresses an infected person’s HIV viral load. It is unclear, however, whether the contextual risk of incident HIV is optimally reduced by widespread individual-level suppression of HIV viral load alone or in combination with other HIV prevention services. HIV service coverage and community norms can influence risk in small area geographies; and contextual factors, like gender inequality and stigma, may foster environments conducive to HIV transmission. Yet, the relationship between places with high HIV levels and the clustering of area risk factors is unknown. The goal of this dissertation is to learn if and how a geographically focused combination implementation strategy could reduce population-level HIV risk. Analyses explored whether small area risk profiles explain area differences in HIV. The guiding hypothesis is that in high HIV prevalence settings, low HIV service uptake in a geographically defined area increases the prevalence of high HIV viremia, leading to greater HIV transmission and incident HIV. Methods: A systematic review was conducted to examine the association between population-level measures of HIV viral load and incident HIV infection in generalized and concentrated epidemics. Publications were English, peer-reviewed articles published from January 1, 1995 through February 15, 2019 that explicitly defined HIV viral load and assessed outcomes of HIV recency, incidence, seroconversion, or new diagnosis. Studies sampled general or key populations through population-based surveillance registries, household-based enumeration, cluster sampling, or respondent driven sampling. Descriptive statistics summarized review findings. The Swaziland HIV Incidence Measurement Survey (SHIMS) data were used for the remaining analyses. Using a two-stage cluster-based design, a nationally representative, household-based sample of adults, ages 18-49 years was enrolled from December 2010 to June 2011 in Eswatini. Consenting adults completed an interview and received home-based rapid HIV testing and counseling. All seropositive samples were tested for HIV viral load using the COBAS AmpliPrep/Taqman HIV-1 Test, v 2.0. Adults testing HIV-seronegative were enrolled in a prospective cohort for the direct observation of HIV seroconversion, completing an interview and home-based rapid HIV testing six months later. Multi-level latent class modeling was performed to identify statistically significant combinations of HIV risk factors and to classify the combinations into small area risk profiles. In the cross-sectional sample, linear regression with robust standard errors assessed the correlation between area profiles and places with high levels of uncontrolled HIV infection, or HIV core areas, measured by the area prevalence of detectable virus (≥20 copies/milliliter) among HIV-positive adults and among all adults, regardless of HIV status. In the prospective cohort, generalized linear regression of longitudinal data assessed the association between area profiles and places prone to new HIV infections (i.e., HIV susceptible areas), measured by area-level HIV seroconversions. Results: The systematic review found an evidence base primarily of lower quality studies and inconsistent HIV viral exposure measurement. Overall findings supported a relationship between increasing levels of suppressed HIV in HIV-infected populations and fewer new infections over time. Better quality studies consistently showed higher population viremia (i.e. HIV viral quantity among all persons, regardless of HIV status) associated with HIV incidence in high prevalence populations; population viral load (i.e., HIV viral quantity among only HIV-positive persons) did not show an association with incident HIV in high prevalence, general populations and was inconsistent in key populations. To determine whether area risk profiles can pinpoint HIV core areas, latent class modeling was used to categorize 18,172 adults into one of six HIV risk types. The risk typology, classified through unique combinations of HIV service uptake and sexual risk behaviors, conveyed an adult’s propensity for HIV transmission and/or acquisition risk. The model next identified the area-level composite prevalences of HIV risk types; estimated the three most frequent, unique composite combinations; and categorized them into area risk profiles characterizing HIV risk: low-moderate acquisition risk, moderate acquisition/transmission risk, and high acquisition/transmission risk. The high acquisition/transmission areas comprised the largest proportions of highest risk transmission and acquisition types. The prevalence of detectable viremia progressively increased from low-moderate acquisition, moderate acquisition/transmission, and high acquisition/transmission profiles [17.7%, 25.4%, and 35.1%, respectively]. When compared with low-moderate acquisition areas, the prevalence of detectable viremia was 7.4% [p<.001] higher in moderate acquisition/transmission areas and 17.1% [p<.001] higher in high acquisition/transmission areas. The prevalence of detectable viral load significantly decreased from low-moderate acquisition to moderate acquisition/transmission areas [76.6% versus 68.7%, p<.001], and was significantly higher in high acquisition/transmission areas by 7.3% [p<.001], when compared with low-moderate acquisition areas. To determine whether area risk profiles can predict HIV susceptible areas, a total of 18,172 adults were surveyed of which 4396 [24%] had detectable viremia. 11,880 [96%; n=12,357] HIV-seronegative adults enrolled in the prospective cohort and 11,155 [94%] of them completed an endline visit. Four area profiles were identified, defined by unique patterns in prevalence of HIV viremia and of sexual risk behaviors. The proportion of HIV susceptible areas progressively increased from Profiles A, B, C, and D [14.3%, 21.8%, 24.6%, and 30.8%, respectively]. HIV susceptible areas were more than twice as likely to occur in Profile D than Profile A environments [RR 2.13, 95% confidence interval (CI) (1.13, 4.00); p=0.02]. Profile D areas had prevalences of unknown partner HIV status and detectable viremia at 28% and 24%, respectively. In contrast, Profile A areas had prevalences of only 8% with unknown HIV status and 31% with detectable viremia. Conclusion: This dissertation shows that geographic risk profiles can explain differences in population-level HIV outcomes. Risk factors spatially cluster in predictable, meaningful combinations that can inform an area typology of HIV risk. The co-location of adults predisposed to greater HIV risk may heighten levels of uncontrolled HIV infection, thereby creating potential area sources of ongoing transmission; however, the concurrent levels of other risk factors may have more influence in reducing population-level incidence than previously considered. A composite indicator of contextual HIV risk may reveal places core to HIV transmission and susceptible to HIV acquisition. Such area profiles may help identify the combination of locally specific risk factors that readily promulgate HIV and better inform the design of place-based HIV intervention packages to enhance current strategies towards global HIV control.

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