Master of Public Health - MPH / Each year approximately 600 000 infants, most of them in Sub-Saharan Africa are born with HIV infection as a result of mother to child transmission of HIV. Whereas significant progress has been made in reduction of mother to child transmission of HIV in developed countries, the situation remains desperate in developing countries. Progress has been hampered by shortage of staff, facilities, limited access to voluntary counselling and testing and lack of support for women by their partners and communities. The challenge is to increase voluntary counselling and testing uptake during antenatal care. Onandjokwe district in Northern Namibia is currently introducing the Prevention of Mother to Child Transmission Program (PMTCT). It has been found the previous PMTCT programs have failed because they adopted a top down approach where there was no community consultation. This study was conducted to explore the community perceptions, knowledge and attitudes regarding mother to child transmission of HIV through focus group discussions and in-depth interviews of key community members. / South Africa

Philosophiae Doctor - PhD / One of the most common HIV-associated opportunistic infections is candidiasis, caused by Candida albicans or other Candida species. In immune suppressed subjects, this commensal organism can cause an increase in patient morbidity and mortality due to oropharyngeal or systemic dissemination. Limited information exists on the prevalence and antifungal susceptibility of Candida species in the African continent, the most HIV-affected region globally and home to new and emerging drug resistant Candida species. The mechanisms of Candida drug resistance in the African continent have also not been described. In this study, 255 Candida species isolated from the oral mucosa of HIV-positive South African and Cameroonian patients were identified using differential and chromogenic media and their drug susceptibility profiles tested using the disk diffusion method and the TREK Sensititre system, an automated broth microdilution method. Candida cell wall fractions were run on SDSPAGE and HPLC-MS with the aim of identifying peptides specifically expressed by antifungal drug resistant isolates. Comparisons between the two groups of isolates revealed differences in Candida species prevalence and drug susceptibility with interesting associations observed between specific drug resistance and duration of ARV therapy. This study showed that fluconazole, the drug of choice for the treatment of candidiasis in the African continent, is not an effective therapy for most cases of Candida infection, and suggests that regional surveillance be implemented in the continent. A multiple-drug resistant Candida strain was identified in this study, a finding that has not previously been documented. The use of proteomics tools allowed for the identification of peptides involved in drug resistance and the elucidation of Candida colonization mechanisms in HIV-infected African patients.

Macrophages can be polarized into M1 and M2 macrophages based on the composition of the milieu. Human macrophages have been poorly characterized. In this study, various macrophage subsets were generated by treating monocyte-derived macrophages (MDMs) with IFNγ (M1), IL-4 (M2a), LPS and IL-1β (M2b) or IL-10 (M2c) which were characterized with respect to their cell surface marker profile and functional profile in the context of cytokine production, susceptibility to HIV infection and apoptosis. Each polarization state demonstrated a unique cell surface marker profile and cytokine profile. In addition M1 macrophages were shown to produce IFNγ post TLR stimulation. Moreover, M1 macrophages were highly sensitive to apoptosis following Smac mimetic treatment. Furthermore, M2a and M2c macrophages were resistant to apoptosis, induced by PI3K blockage and IAPs degradation respectively, and at the same time supported productive HIV infection unlike the other macrophage subsets. These findings might lead to better understanding of HIV reservoir formation and be used to develop therapies to eradicate it.

In the gut-associated lymphoid tissues, Th17 cells mediate mucosal homeostasis and inflammation. During HIV infection, Th17 cells become depleted and functionally impaired, which is implicated in the pathogenesis of chronic inflammation in patients treated with highly active antiretroviral therapy. IL-7 is a cytokine that mediates homeostatic responses in T lymphocytes, such as proliferation and survival, which are dysregulated during HIV infection. Whether similar dysregulation occurs in Th17 cells has yet to be reported. IL-7 receptor α (CD127) expression and IL-7 responses were therefore measured in blood-derived Th17 cells from uninfected individuals and effectively treated, HIV-infected individuals by flow cytometry. Th17 cells from uninfected individuals expressed CD127 and, in response to IL-7, exhibited phosphorylation of STAT5, upregulation of Bcl-2, and proliferation. During HIV infection, expression of CD127 and pSTAT5 in Th17 cells was comparable to that observed in cells from uninfected individuals. Interestingly, expression of Bcl-2 was upregulated while proliferation was dramatically impaired. These findings may provide further insight into the mechanisms by which Th17 cells fail to become restored during HIV infection.

L’infection par le VIH est caractérisée en l’absence d’intervention par une évolution progressive vers un état d’immunodépression favorisant la survenue d’affections opportunistes et entrainant le décès. La connaissance de l’évolution spontanée de l’infection par le VIH repose sur les données observationnelles issues des cohortes. La meilleure façon d’aborder l’histoire naturelle de cette infection est de l’étudier à partir de la date de séroconversion, ce qui ne peut se faire que dans les cohortes dites incidentes. Ces cohortes incidentes font appel à des structures parfois lourdes et des procédures rigoureuses que l’on peut plus aisément mettre en place dans les pays à ressources élevées. Les cohortes de personnes à date estimée de séroconversion permettent d’identifier les facteurs de risque de la transmission, d’étudier l’évolution de l’infection, d’étudier l’évolution de ses marqueurs et ses déterminants en minimisant le biais de sélection inhérent aux études prévalentes. L’évolution naturelle concerne la période qui s’écoule entre la date d’infection et le décès pour les patients qui n’ont pas bénéficié de prescription du traitement antirétroviral. Cette période s’arrête à la date de prescription des antirétroviraux pour ceux qui en bénéficient.La cohorte ANRS 1220 Primo-CI de personnes à date estimée de séroconversion pour le VIH-1 a été mise en place en juin 1997 sur le site de l'ANRS d'Abidjan en Côte d'Ivoire, au Centre national de transfusion sanguine (CNTS), avec la coordination de l'INSERM U330/593/897-ISPED de Bordeaux. C’est l’une des rares cohortes de séroconverteurs pour le VIH-1 dans le contexte des pays à faibles ressources et l’unique en Afrique de l’ouest. Dans cette cohorte de patients dépistés parmi les donneurs de sang effectuant plus de deux dons de sang par an, les données cliniques et biologiques ont été recueillies régulièrement pour tous les patients, tous les six mois depuis leur inclusion dans la cohorte.Les principaux apports de la cohorte Primo-CI dans la lutte contre le VIH en Côte d’Ivoire, ont consisté à recueillir des informations sur les facteurs de risque d’infection par le VIH pour aider à améliorer la sélection des donneurs de sang. La cohorte Primo-CI a permis d’améliorer également les capacités de la structure de prise en charge qui a servi de centre de recrutement et de prise en charge des patients de la cohorte. Cette cohorte a contribué à la mise en place d’un cadre d’échanges réguliers entre les médecins chargés de la sélection des dons de sang et l’équipe de la cohorte Primo-CI.Nos données ont fourni des estimations de la probabilité d'atteindre les critères d'initiation des antirétroviraux depuis le premier contact dans une population de séroconverteurs récents pour le VIH en Afrique de l’ouest et de la probabilité de survenue des événements morbides au cours du temps.L'ADN intracellulaire du VIH-1 était la variable la plus fortement associée à la progression de la maladie, indépendamment des autres variables explicatives. Il était suivi des lymphocytes CD4 avec une association plus faible. La charge virale plasmatique VIH-1 était faiblement associée à la progression de la maladie et ce après la prise en compte de l'ADN.La cohorte ANRS 1220 Primo-CI a participé à plusieurs travaux de collaborations portant sur les seuils d’éligibilité aux antirétroviraux, la comparaison de la baisse des lymphocytes CD4 avec des patients européens, la morbidité et la mortalité liées au SIDA et le rôle prédictif de l'ADN intracellulaire du VIH-1. Elle a également contribué à la réalisation de travaux scientifiques en virologie et immunologie qui ne portent pas sur l’objectif principal de ce travail. / In the absence of any intervention, HIV infection is characterized by a gradual evolution towards a state of immunosuppression favoring the occurrence of opportunistic infections and causing death. The natural history of HIV infection is usually documented based on data from observational cohorts. But the best way to address the natural history of this infection is to observe subjects from the date of their seroconversion (within an “incident” cohort). However these incident cohorts often involve heavy structures and complex procedures that are more easily set-up in high-resources countries.Cohorts of individuals with estimated date of seroconversion can identify risk factors for HIV transmission, study the evolution of the infection, and study the evolution of its markers and determinants by minimizing the selection bias inherent in prevalent studies. The natural history of HIV is defined by the period between the date of infection and either the date of death for patients who were not prescribed antiretroviral therapy or the date of antiretroviral therapy prescription for others.The ANRS 1220 Primo-CI Cohort of people with a known date of HIV-1 seroconversion was launched in June 1997 in the site of the ANRS Abidjan in Côte d'Ivoire, National Blood Transfusion Centre (CNTS), with the coordination of U330/593/897-ISPED INSERM Bordeaux. This is one of the few adult cohorts of HIV-1 seroconverters in the context of low-resource countries and the only one in West Africa. Within this cohort of patients recruited among blood donors performing more than two blood donations per year, the clinical and laboratory data were collected routinely every six months from their inclusion.One of the main contributions of the Primo-CI cohort in the fight against HIV in Côte d’Ivoire was the collection of information on the risk factors for HIV infection. It helped to improve the selection of blood donors. It also helped to improve the capacity of the health structure where the cohort patients were recruited and followed-up.This cohort has contributed to establish a system for regular exchanges between physicians responsible for the selection of blood donations and the team of the Primo-CI cohort. Our data have provided estimates of the probability of reaching the criteria for initiating antiretroviral drugs from the first contact and the probability of occurrence of morbid events over time, in a population of recent HIV seroconverters in West Africa.The HIV-1 intracellular DNA was the variable most strongly associated with disease progression, independently of other variables. It was followed by lower CD4. Plasma viral load HIV-1 was poorly associated with disease progression after taking into account the HIV-1 intracellular DNA.Finally, the ANRS 1220 Primo-CI cohort participated in several collaborative studies regarding the threshold of eligibility for antiretroviral drugs, the comparison of the decrease in CD4 lymphocytes with European patients, morbidity and mortality related to AIDS and the predictive role of HIV-1 intracellular DNA. It also contributed to scientific studies in virology and immunology that do not concern the main objective of this work.

Masters in Public Administration - MPA / The South African Department of Basic Education (DBE), in response to escalating HIV infection, teenage pregnancy and risky sexual behaviours among learners, introduced and implemented comprehensive sexuality education (CSE) within the Life Orientation (LO) curriculum using scripted lesson plans (SLP) in the year 2015. The implementation of CSE globally, and in Africa, though assessed to be successful, is not without its challenges. In South Africa, A five year DBE pilot programme (2015-2020) is being implemented and facilitated by Education Development Centre (EDC) in five provinces of South Africa. Life Orientation educators are responsible for the implementation of CSE lessons, utilising the newly developed DBE CSE scripted lessons plans in the five pilot provinces.

Magister Artium (Development Studies) - MA(DVS) / Malawi had an estimated HIV prevalence of 9.6% with about 9.2% of its adult population living with HIV/AIDS in 2018. HIV Counselling and Testing (HCT) is essential to the prevention of HIV infection, HIV treatment and access to care and support services. However, despite the availability of free HCT services, the uptake of HCT services has been low among men in Malawi. This study assessed barriers and enablers of HCT uptake among men aged 18-49 in Chileka Health Area in Lilongwe District.

RUNX1 overlapping RNA (RUNXOR) is a long noncoding RNA and a key regulator of myeloid-derived suppressor cells (MDSCs) via targeting runt-related transcription factor 1 (RUNX1). We and others have previously reported MDSC expansion and inhibition of host immune responses during viral infections; however, the mechanisms regulating MDSC differentiation and suppressive functions, especially the role of RUNXOR-RUNX1 in the regulation of MDSCs in people living with HIV (PLHIV), remain unknown. In this study, we demonstrate that RUNXOR and RUNX1 expressions are upregulated in MDSCs that expand and accumulate in human PBMCs derived from PLHIV. We found that the upregulation of RUNXOR and RUNX1 is associated with the expressions of several key immunosuppressive molecules, including arginase 1, inducible NO synthase, STAT3, IL-6, and reactive oxygen species. RUNXOR and RUNX1 could positively regulate each other's expression and control the expressions of these suppressive mediators. Specifically, silencing RUNXOR or RUNX1 expression in MDSCs from PLHIV attenuated MDSC expansion and immunosuppressive mediator expressions, whereas overexpressing RUNXOR in CD33+ myeloid precursors from healthy subjects promoted their differentiation into MDSCs and enhanced the expression of these mediators. Moreover, loss of RUNXOR-RUNX1 function in MDSCs improved IFN-γ production from cocultured autologous CD4 T cells derived from PLHIV. These results suggest that the RUNXOR-RUNX1 axis promotes the differentiation and suppressive functions of MDSCs via regulating multiple immunosuppressive signaling molecules and may represent a potential target for immunotherapy in conjunction with antiviral therapy in PLHIV.

A dissertation submitted in partial fulfillment of the requirements for the Degree of Applied Master of Arts in the Department of Psychology, Faculty of Arts at the University of Zululand, 2000. / This study was aimed at describing levels of AIDS knowledge, HIV infection and risk reduction, attitudes towards AIDS and people with AIDS (PWAs), sexual behaviour, condom use as well as attitudes, beliefs and perceptions about condoms, the impact which perceived norms and self-efficacy have on condom use, sexual behaviour and AIDS preventative behaviour(APB). Results of the study have shown that knowledge levels were high among Zululand university students. A comparison of the different sexes shows that females had a slightly higher level of knowledge than males. The three most popular choices identified as sources of AIDS knowledge were campus health, clinic/doctor and a friend. The majority of the sample was negative, rejecting and intolerant with regard to the proximity to PWAs. Many also held judgemental, fatalistic and moralistic attitudes with regard to AIDS and PWAs. Half of the respondents showed compassion with regard to the legal and social welfare of PWAs. The majority of the sample was sexually active, with a substantial number of subjects engaging in sexual intercourse with multiple partners. Condoms were least used among this latter group and only a third used condoms consistently. However, the majority intended to use condoms in future sexual encounters and this intention was stronger among students with one sexual partner. The Pearson product moment correlation revealed that attitudes, perceived norms and self-efficacy were associated with condom use and sexual behaviour. Knowledge of AIDS per se had no impact on sexual behaviour and condom use. The multiple regression analysis showed that attitudes and self-efficacy are the strongest predictor variables of condom use. Finally gender had no effect on sexual activity, number of sexual partners, condom use, perceived norms and self-efficacy.

In this thesis we develop a mathematical model to describe HIV-1 evolution during the first stages of infection (approximately within 40-60 days since onset), when one can assume exponential growth and random accumulation of mutations under a neutral drift. We analyze the Hamming distance (HD) distribution under different models (synchronous and asynchronous) in the absence of selection and recombination. In the second part of the thesis, we introduce recombination and develop a combinatorial approach to estimate the new HD distribution. We conclude describing a T statistic to test significance differences between the HD of two genetic samples, which we derive using U-statistics.