Li, Huizhen. / "March 2008." / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 139-150). / Abstracts in English and Chinese. / Abstract --- p.ii / Acknowledgement --- p.vii / Abbreviations --- p.ix / Introduction --- p.1 / Chapter 1.1 --- HIV and AIDS --- p.4 / Chapter 1.1.1 --- HIV Transmission Routes --- p.5 / Chapter 1.1.2 --- HIV Related Risk Behaviors --- p.6 / Chapter 1.2 --- HIV Burden --- p.7 / Chapter 1.2.1 --- HIV Infection in China --- p.7 / Chapter 1.2.2 --- HIV Infection in Hong Kong --- p.9 / Chapter 1.2.3 --- Methadone Treatment in Hong Kong --- p.10 / Chapter 1.3 --- Objectives and Hypothesis --- p.14 / Chapter 1.4 --- Organization of This Thesis --- p.15 / Literature Review --- p.16 / Chapter 2.1 --- Search Methods --- p.18 / Chapter 2.1.1 --- Formulating Review Questions --- p.18 / Chapter 2.1.2 --- Search Strategy --- p.19 / Chapter 2.1.3 --- Inclusion and Exclusion Criteria --- p.21 / Chapter 2.2 --- Assessing the Quality of Studies --- p.22 / Chapter 2.3 --- Search Results --- p.23 / Chapter 2.3.1 --- Descriptive Summary --- p.25 / Chapter 2.3.2 --- Critique of Reviewed Articles --- p.33 / Chapter 2.4 --- Implication on Planning of Current Study --- p.37 / Chapter 2.4.1 --- Summary of Reviewed Articles --- p.37 / Methods for Exploring Predictors of HIV Risk --- p.40 / Chapter 3.1 --- Data Source --- p.42 / Chapter 3.1.1 --- Data Management in Methadone Clinics --- p.42 / Chapter 3.1.2 --- Source of Data --- p.43 / Chapter 3.2 --- Data Transformation --- p.45 / Chapter 3.3 --- Framework for assessing outcome --- p.48 / Chapter 3.3.1 --- Study population in different analyses --- p.48 / Chapter 3.3.2 --- Risk Score --- p.49 / Chapter 3.3.3 --- Independent Variables --- p.50 / Chapter 3.4 --- Generalized Linear Model --- p.52 / Chapter 3.5 --- Logistic Regression Model --- p.54 / Chapter 3.6 --- Multilevel Analyses --- p.55 / Chapter 3.6.1 --- Variables --- p.56 / Chapter 3.6.2 --- Definition of 'Neighborhood' --- p.56 / Chapter 3.6.3 --- Individual Variables --- p.60 / Chapter 3.6.4 --- Framework for Analyses --- p.60 / Chapter 3.7 --- Field Study --- p.63 / Results: Community Variation of HIV Risk --- p.65 / Chapter 4.1 --- Demographic Description --- p.67 / Chapter 4.1.1 --- Age distribution --- p.67 / Chapter 4.1.2 --- Gender Distribution --- p.68 / Chapter 4.1.3 --- Proportion of New Admission --- p.72 / Chapter 4.2 --- Drug Taking Profile --- p.74 / Chapter 4.2.1 --- Heroin Use --- p.74 / Chapter 4.2.2 --- Injecting Heroin Users --- p.77 / Chapter 4.3 --- HIV related risk behaviors --- p.81 / Chapter 4.3.1 --- Injection History --- p.81 / Chapter 4.3.2 --- Risky Injection Practices --- p.87 / Chapter 4.3.3 --- Sexual Behaviors --- p.93 / Chapter 4.4 --- Correlation between Demographics and Risk Score --- p.94 / Chapter 4.4.1 --- General Linear Regression Model Coefficient --- p.94 / Chapter 4.4.2 --- Risk Predictors in Logistic Regressions --- p.95 / Chapter 4.5 --- Neighborhood Effect --- p.100 / Chapter 4.6 --- On-site Observation --- p.103 / Chapter 4.6.1 --- Demographic Variations --- p.103 / Chapter 4.6.2 --- Drug Use Variations --- p.104 / Chapter 4.6.3 --- Social Background --- p.105 / Discussion --- p.111 / Chapter 5.1 --- Neighborhood Effect --- p.113 / Chapter 5.1.1 --- Variation across Communities --- p.113 / Chapter 5.1.2 --- Implication on Social Network of IDUs --- p.115 / Chapter 5.2 --- Decline of Admissions --- p.117 / Chapter 5.2.1 --- Decrease of New Admissions --- p.117 / Chapter 5.2.2 --- Decline of Readmission in 2003 --- p.119 / Chapter 5.3 --- Female IDU Population --- p.121 / Chapter 5.4 --- Limitations --- p.125 / Chapter 5.4.1 --- Importance of Individual Level Variables and Community Level Variables --- p.125 / Chapter 5.4.2 --- Reliability of Self-reported Data --- p.126 / Chapter 5.4.3 --- Duplicates of Readmissions --- p.126 / Chapter 5.4.4 --- Definition of Syringe Reuse --- p.127 / Chapter 5.4.5 --- Choice of Models --- p.129 / Conclusion and Future Directions --- p.131 / Chapter 6.1 --- Summary of Results --- p.133 / Chapter 6.2 --- Implication of results --- p.134 / Chapter 6.3 --- Future Directions --- p.136 / Bibliography --- p.139

Com a finalidade de estudar a soroprevalência do Vírus da Imunodeficiência Humana, HIV, e infecções com transmissão relacionadas, entrevistamos e colhemos sangue de 197 usuários de drogas injetáveis, UDIs, amostrados através da metodologia de \"bola de neve\" (snow-balling), da cidade de Santos, São Paulo, Brasil. Nesta cidade a estimativa de UDIs, 10.000 indivíduos, compreende cerca de 2% de sua população. Soroprevalências de HIV, hepatites B e C, sífilis e HTLV (1 ou 2) foram obtidas e comparadas com 197 doadores de sangue pareados por idade e sexo. As soroprevalências encontradas foram de 62% para HIV, 75% para HCV, 75% para HBV, 34% para sífilis, e 25% para o HTLV (1 e 2) entre os UDIs, comparado com 0%; 2%; 23%; 12% e 1% entre os doadores do banco de sangue, respectivamente. Os fatores de risco para transmissões parenterais nesta comunidade de UDIs são mais importantes que para transmissão sexual, embora a última deva ser considerada quando se planejar estratégias de controle. Além disso, estimamos a Razão de Reprodutibilidade Basal, R0, para o HIV entre os UDIs. Usando um modelo clássico para infecções transmitidas por vetores de Macdonald adaptado para \"agulhas\", o valor de R0 foi estimado em 28 e 98, considerando uma distribuição dos inóculos infectantes como homogênea ou heterogênea respectivamente . Esta estimativa foi baseada somente em parâmetros de transmissão parenteral nesta comunidade de UDIs. Usando este modelo a estimativa da soroprevalência do HIV no equilíbrio (0,67) é bem próxima à soroprevalência observada (0,62). / In order to study the seroprevalence of HIV and infections with related transmission patterns, as hepatitis B and C, syphilis and HTLV (1 and 2), we interviewed and bled 197 IDUs, sampled by snow-balling and compared with 197 blood donors matched for age and sex, both groups from the city of Santos, Sao Paulo, Brazil. Seroprevalences found were 62% for HIV, 75% for HCV, 75% for HBV, 34% for syphilis and 25% for HTLV (1 or 2) among IDUs, which compare with 0.0%, 2%, 23%, 12%, and 1% for blood donors, respectively. The risk for parenterally transmitted infections in this IDUs community is higher than that for sexually transmitted one. We also estimated the Basic Reproduction Ratio, R0, for HIV among IDUs. Using a model adapted from the classical Macdonald\'s model for vector-born infection, the R0 resulted in 28 and 98, assuming an homogeneous or heterogeneous distribution of infective inoculae, respectively. This estimation was based only on parenteral transmission. Using this model the expected equilibrium for HIV seroprevalence (0.67) is close to the observed seroprevalence (0.62)

Com a finalidade de estudar a soroprevalência do Vírus da Imunodeficiência Humana, HIV, e infecções com transmissão relacionadas, entrevistamos e colhemos sangue de 197 usuários de drogas injetáveis, UDIs, amostrados através da metodologia de \"bola de neve\" (snow-balling), da cidade de Santos, São Paulo, Brasil. Nesta cidade a estimativa de UDIs, 10.000 indivíduos, compreende cerca de 2% de sua população. Soroprevalências de HIV, hepatites B e C, sífilis e HTLV (1 ou 2) foram obtidas e comparadas com 197 doadores de sangue pareados por idade e sexo. As soroprevalências encontradas foram de 62% para HIV, 75% para HCV, 75% para HBV, 34% para sífilis, e 25% para o HTLV (1 e 2) entre os UDIs, comparado com 0%; 2%; 23%; 12% e 1% entre os doadores do banco de sangue, respectivamente. Os fatores de risco para transmissões parenterais nesta comunidade de UDIs são mais importantes que para transmissão sexual, embora a última deva ser considerada quando se planejar estratégias de controle. Além disso, estimamos a Razão de Reprodutibilidade Basal, R0, para o HIV entre os UDIs. Usando um modelo clássico para infecções transmitidas por vetores de Macdonald adaptado para \"agulhas\", o valor de R0 foi estimado em 28 e 98, considerando uma distribuição dos inóculos infectantes como homogênea ou heterogênea respectivamente . Esta estimativa foi baseada somente em parâmetros de transmissão parenteral nesta comunidade de UDIs. Usando este modelo a estimativa da soroprevalência do HIV no equilíbrio (0,67) é bem próxima à soroprevalência observada (0,62). / In order to study the seroprevalence of HIV and infections with related transmission patterns, as hepatitis B and C, syphilis and HTLV (1 and 2), we interviewed and bled 197 IDUs, sampled by snow-balling and compared with 197 blood donors matched for age and sex, both groups from the city of Santos, Sao Paulo, Brazil. Seroprevalences found were 62% for HIV, 75% for HCV, 75% for HBV, 34% for syphilis and 25% for HTLV (1 or 2) among IDUs, which compare with 0.0%, 2%, 23%, 12%, and 1% for blood donors, respectively. The risk for parenterally transmitted infections in this IDUs community is higher than that for sexually transmitted one. We also estimated the Basic Reproduction Ratio, R0, for HIV among IDUs. Using a model adapted from the classical Macdonald\'s model for vector-born infection, the R0 resulted in 28 and 98, assuming an homogeneous or heterogeneous distribution of infective inoculae, respectively. This estimation was based only on parenteral transmission. Using this model the expected equilibrium for HIV seroprevalence (0.67) is close to the observed seroprevalence (0.62)

Source: Dissertation Abstracts International, Volume: 70-03, Section: B, page: 1572. Adviser: Lu-Yu Hwang. Includes bibliographical references.

Thesis (Dr. P.H.)--University of Texas Health Science Center at Houston, School of Public Health, 2007. / Source: Dissertation Abstracts International, Volume: 68-10, Section: B, page: 6615. Adviser: Michael W. Ross. Includes bibliographical references.