Thesis (M. Sc. (Microbiology)) -- University of Limpopo, 2022 / Sexually transmitted infections represent one of the main health problems related to reproductive and sexual function, constituting one of the main causes of infertility. Plants have been employed traditionally in treating diseases for centuries. Elephantorrhiza burkei, Securidaca longepedunculata and Wrightia natalensis medicinal plants were selected for this study based on their use in traditional medicine to treat sexual health problems in Limpopo Province. The aim of the study was to determine antimicrobial and antioxidant properties of the selected plants. Different extraction procedures coupled with solvents of varying polarities were used in the extraction of the plant materials. Possible microbial contaminants were identified using the VITEK 2 instrument. Qualitative phytochemical analysis was determined using standard chemical tests and Thin-Layer Chromatography. Total polyphenol content was quantified calorimetrically. Antioxidant activity was quantified using 2, 2-diphenyl- 1-picrylhydrazyl (DPPH) and ferric reducing power assays. In vitro antimicrobial activities were determined using a broth micro-dilution assay and bioautography. Combinational effects of the addition of multiple plant species on antimicrobial activity were investigated for additive, synergistic and antagonistic interactions. The plant species phytochemical profile contained polyphenols that are known to have antimicrobial effects against two Gram-positive bacteria, Staphylococcus aureus (ATCC 29213) and Enterococcus faecalis (ATCC 29212), a Gram-negative bacterium, as well as the fungus, Candida albicans (ATCC 10231). Elephantorrhiza burkei exhibited high antioxidant activity and antimicrobial activity against the test pathogens, although most of the interactions were antagonistic and indifferent. Toxicity was found in the herbal treatment and acute toxicity was found in the selected plants. Based on the good correlations which were found in E. burkei, it was selected for bioactivity guided by an isolation of antibacterial compounds. Elephantorrhiza burkei was not successfully isolated, but the fraction collected showed exceptional biological activity that validates its usage against disease-causing pathogens related to sexually transmitted infections, which compromises male sexual health. This study suggests that the evaluated plants are potential sources of novel anti-infective agents. Further in vivo and in vitro studies are recommended for all the plants, respectively. / University of Limpopo and CSIR

Clinical and experimental studies have shown that estradiol (E2) can enhance protection against sexually transmitted infections such as HSV-2 and HIV-1. Antigen presenting cells (APCs) such as Dendritic cells (DCs) are critical for generating immune responses against these infections, and it is unclear whether unique factors present in the genital mucosa can influence immune responses by directly modulating the phenotype and function of local APCs. To address this, I hypothesized that sex hormones, such as E2 and innate factors in the local microenvironment can regulate the phenotype and function of vaginal APCs. The work summarized in this thesis addressed this central hypothesis. In the first section of the thesis, I examined whether vaginal APCs were distinct in their phenotype and function compared to those in other mucosal tissues or spleen. The results show that the vagina was enriched in CD11c+ CD11b+ MHCII− DCs. Functionally, vaginal tissue cells (TC) and CD11c+ DCs were more potent inducers of Th17 responses in co-cultures with CD4+ T cells, compared to lung, small intestine or spleen APCs. E2 was critical for the conditioning of vaginal DCs to prime these Th17 responses through an IL-1-dependent pathway, indicating that sex hormones such as E2 can directly influence the function of vaginal APCs. In the next section, I determined whether other co-factors in the genital microenvironment such as microflora and innate lymphocytes could also influence vaginal APC functions. We found that while microflora was not essential, IL-17 produced by innate lymphocytes was critical for the induction of IL-1 from DCs, and consequently for potentiating Th17 responses. Finally, I attempted to develop an in vivo mouse model where the effect of E2 on vaginal APCs could be examined in the context of genital HSV-2 infection. I tested a 7-day injectable E2 and a 21-day E2 pellet delivery model, and found that both regimes had limitations for examining E2-effects on anti-viral responses. Yet, subsequent to the work done in this thesis, we were able to confirm our observations of E2-conditioned Th17 responses in vivo in an intranasal immunization model utilizing E2 pellet delivery, and thereby addressed the mechanism underlying enhanced anti-viral protection following E2-treatment. In conclusion, this is the first study to show the effect of E2 on genital tract APCs and their ability to prime Th17 responses. It provides future avenues to examine whether modulation of this microenvironment can help optimize vaccine-induced immune responses against STIs. On a more fundamental level, it highlights the need to consider the inherent distinctions in APC populations among different mucosal tissues. / Dissertation / Doctor of Philosophy (PhD)

<p>Sexually transmitted infections (STIs), especially HIV/AIDS and HSV-2, continue to be a devastating burden on societies around the world. The close link between HSV-2 and HIV-1, the role of inflammation in driving these infections, and the limited success and availability of prophylactic and therapeutic measures underscore the need for continued search of alternative means of protection. Characterization of endogenous antimicrobials, especially those local to the female genital tract and actively regulating inflammatory and antiviral responses, could be beneficial for microbicidal trials. Although regulators of mucosal immunity, such as serine antiproteases, trappin-2 and elafin (Tr/E), have been associated with resistance to HIV-1, their antiviral activity remains poorly understood. Thus, the research presented in this thesis centers on characterization of antiviral properties of Tr and E individually and their potential mechanisms in defense against HSV-2 and HIV-1 in the female genital mucosa. Chapter 2 examines Tr/E contribution to antiviral host defense responses elicited by a synthetic mimic of viral dsRNA, polyI:C. Chapter 3 documents the presence and characteristics, including potential mechanisms, of antiviral activity of Tr/E against in vitro and in vivo HSV-2 infection. Chapters 4 and 5 determine the contribution of Tr/E to the natural anti-HIV-1 protection of CVL and structural characteristics, mode(s) of action, and cellular distribution/localization of antiviral Tr/E proteins. Therein, we present novel properties of each Tr/E by demonstrating their inhibitory and multiple effects against both HSV-2 and HIV-1. These effects appear to be mediated either through virus or cells and be associated with altered viral attachment/entry, transcytosis and infection, innate viral recognition, modulated inflammation and increased antiviral protection of cells. Reported antiviral activity of Tr/E was also contextual and exerted, at least in HEC-1A cells, via autocrine/paracrine mode and depended on elafin’s nuclear localization and its unmodified N-terminus. Tr/E may represent viable candidates for further studies in the field of STIs.</p> / Doctor of Philosophy (PhD)

This study explored preparatory students’ perceptions of the risk of contracting the Human Immuno-deficiency Virus (HIV) and sexually transmitted infections (STIs) in Ethopia. It utilised a non-experimental exploratory survey methodology. A range of findings was revealed. Most respondents (67.14%) were knowledgeable about HIV/AIDS and more than half of the respondents knew about STIs. A significant number of respondents (67.1%) were able to describe HIV transmission prevention methods. Twenty one percent of respondents were sexually active and 17.0% of these reported to have used condoms. Twenty nine percent and 4.25% of the respondents had selfperceived risk of contracting HIV infection and STIs respectively. In spite of increased awareness of HIV/AIDS, school youths still engage in high-risk sexual activities and believe that they are unlikely to contract the disease. The study findings have implications for practice, and recommendations are offered for further research / Health Studies / M.A. (Public Health)

The United States has the highest rates of teenage pregnancies, births, abortions, and sexually transmitted infections in the industrialized world. African American teen pregnancies and sexually transmitted infections are on the rise in many rural southwest school districts in the State of Georgia where the sex education curriculum is nonexistent or solely focuses on abstinence. Georgia ranked 4th in cases of primary and secondary syphilis, 6th in AIDS, 12th in gonorrhea, 14th in teen pregnancies, and 17th in chlamydia in the United States in 2012. The purpose of this qualitative study was to evaluate the perceptions of residents of a primarily African American rural southwest Georgia community regarding the importance of sex education and their knowledge of the school district's sex education curriculum. It specifically investigated abstinence-only sexual education using Bronfenbrenner's ecological learning theory. Study participants (n = 25) were African American youths in 9th grade, their parents, school officials, religious leaders, policymakers, and health advocates. The research questions were designed to investigate participants' knowledge of sexual health and effective sex education curricula for their school district. Data were collected from the participants via semi-structured interviews. MAXQDA 11.1 software was used for thematic analysis of transcribed interviews. The findings demonstrated community support for a comprehensive sex education curriculum and the need for a new paradigm in social policy that suggests initiatives should be evidence-based to achieve maximum efficacy in policy analysis. The study provides a baseline for school officials to assess community opinions regarding the acceptance of a comprehensive sex education curriculum.

La question des infections sexuellement transmissibles (IST) en Afrique a longtemps été négligée par des chercheurs africains spécialistes en sciences sociales, en raison notamment du tabou qui entoure la sexualité dans ce continent. Toutefois, les dernières décennies ont donné lieu à plusieurs recherches menées principalement par les Européens africanistes sur ces pathologies grâce à l’émergence de la pandémie actuelle du Sida. La plupart des travaux réalisés sont axés sur les facteurs de risque, les mécanismes de diffusion, les croyances et les attitudes populaires face à ces maladies, les politiques de lutte, etc. Mais les études historiques consacrées aux IST sont très rares. Celles qui existent ont surtout mis en évidence la dimension démographique axée sur le problème de la dénatalité en laissant dans l’ombre le contexte socio-historique et les conditions socio-épidémiologiques de propagation de ces affections. Au moment où le Sida fait des ravages dans le monde et tout particulièrement en Afrique subsaharienne, l’intérêt d’une réflexion historique sur les IST au Congo n’est plus à démontrer. Contrairement à une affirmation classiquement admise dans la littérature, selon laquelle la lutte contre les IST au sein de la population congolaise fut un franc succès pour les autorités coloniales surtout après la Deuxième Guerre mondiale, cette thèse montre plutôt l’augmentation de la prévalence des IST dans le temps. Les archives inédites et l’analyse des données révèlent que cette progression continue est la conséquence de l'urbanisation accélerée et de la monétarisation de la société et de la sexualité entraînant des modes de vie propres à la société coloniale urbaine. Les villes issues de ce processus deviendront non seulement des espaces d’acculturation et de modernité, mais aussi des lieux d’expansion de ces maladies. Le développement de la prostitution et la multiplicité des partenaires sexuels, à travers les unions plus libres et momentanées, sont les principaux facteurs explicatifs de cette observation. On présente généralement de manière panégyrique l’oeuvre sanitaire coloniale de la Belgique au Congo comme ‘‘modèle’’. Pourtant, aucune étude n’a déjà été menée pour examiner, de manière chiffrée, les aspets liés aux différences de santé entre les Congolais et les Blancs. Cette dissertation vient combler les lacunes existantes dans ce domaine. De ce point de vue, il en résulte de fortes inégalités et des déséquilibres persistants de santé entre ces deux types de populations. Les Congolais beaucoup plus nombreux, socialement défavorisés, ne bénéficient que d’une situation peu ou moins favorable ; tandis que les Blancs, socialement plus favorisés, bénéficient en général d’une meilleure situation sanitaire. Plusieurs indicateurs élaborés dans ce travail sont révélateurs de cette réalité coloniale, en termes d’équipements sanitaires, d’accès et d’utilisation de soins et d’état de santé différencié./ The issue of sexually transmitted infections (STI) in Africa has long been neglected by researchers African social scientists, particularly because of the taboo surrounding sexuality in Africa. However, recent decades have resulted in several research conducted mainly by the European Africanists on these diseases through the emergence of the current pandemic of AIDS. Most of studies are focused on risk factors, distribution mechanisms, the popular attitudes about these infections, control policies... But historical studies on STI are seldom examined. Those that exist are mainly concerning the demographic dimension focuses on the problem of declining birth, leaving the socio-historical and socio-epidemiological spread of such diseases. While AIDS is ravaging the world and especially in sub-Saharan Africa, one thing to mention is that the interest of historical reflection on STI in the Congo is obvious. Contrary to an assertion conventionally accepted in the literature, that the fight against gonorrhea and syphilis among the Congolese population was a success for the colonial authorities, especially after the Second World War, our thesis shows rather the increasing prevalence of STI. The archives and analysis of data indicates this continued progress is the result of special conditions of industrialization and urbanization colonial that make people vulnerable. Cities from this historical process will not only areas of acculturation and modernity, but also places for expansion of these diseases. The development of prostitution and multiple sexual partners through free and temporary unions are the main factors explaining this observation. It has generally praises how the actions of Belgian colonial health in the Congo as 'model'. However, no study has been conducted to establish or to compare quantitatively the health status between Blacks (Congolese) and Withes (Europeans in majority). This essay shows the social health inequalities among these two populations. The Congolese many in number, but more socially disadvantaged have only less favorable conditions to health. While the white people, socially privileged, generally have better health status. Several indicators developed in this study are revealing of the colonial reality in terms of sanitation, access and use of care and health status differential.

Problématique : Les femmes travailleuses du sexe (TS) constituent la population le plus à risque d’infection au VIH dans différents pays d’Afrique subsaharienne. Plusieurs interventions y ont ainsi été menées pour réduire le risque d’infection en influant sur les facteurs de risque. Parmi ces interventions, on peut citer la promotion de l’utilisation du préservatif de même que le dépistage et le traitement des infections sexuellement transmissibles (IST). Cependant, certaines composantes sont peu représentées dans ce panel d’interventions offertes aux femmes TS. Le conseil dépistage volontaire pourrait s’avérer une intervention utile de prévention primaire et secondaire pour cette population mais son acceptabilité est mal connue. Par ailleurs, en termes de surveillance de l’épidémie, l’évaluation de la validité de l’auto-rapport d’utilisation du préservatif, indicateur fréquemment utilisé lors d’enquêtes populationnelles serait souhaitable. Enfin, pour ce qui est de la prévention de l’infection dans cette population, l’effet du désir d’enfant sur l’utilisation non systématique du condom avec le principal partenaire régulier non payant est peu connu. Il en est de même pour la prévalence de certaines IST comme le VPH-16 et l’effet combiné de facteurs sociodémographiques, comportementaux et préventifs sur la présence de ces IST. Objectifs : Les objectifs de cette thèse sont 1) de mesurer l’acceptabilité et les conséquences du conseil dépistage volontaire du VIH chez les femmes TS de Conakry en Guinée; 2) d’évaluer la validité de l’auto-rapport de l’utilisation du préservatif dans cette population grâce à un indicateur biologique de présence de sperme, l’antigène spécifique de la prostate (PSA); 3) d’estimer la fréquence d’utilisation systématique du préservatif avec les partenaires clients et non-clients des femmes TS et d’étudier l’importance du désir d’enfant dans l’utilisation non systématique du préservatif avec le principal partenaire régulier non-client et 4) de mesurer la prévalence des IST et du VIH et d’étudier les facteurs sociodémographiques, comportementaux et préventifs qui y sont associés. Méthodologie : Nous avons mené une étude longitudinale dans la ville de Conakry en Guinée auprès de 421 femmes TS recrutées dans trois services de santé adaptés pour elles. Un devis mixte répété un an plus tard a permis de collecter des données quantitatives et qualitatives. Des analyses biologiques de dépistage des IST et du VIH ont été effectuées. Résultats : Le premier article de résultats présenté dans cette thèse montre que l’acceptabilité du conseil dépistage volontaire est élevée chez les femmes TS. En effet, les taux d’acceptation du test, de retour pour la prise de résultats et de notification du statut sérologique avoisinaient les 100%. Cette acceptabilité semblait être le fait d’une perception de risque d’infection élevé, mais aussi d’une pression sociale du milieu prostitutionnel pour effectuer le dépistage et révéler le statut sérologique. Les conséquences négatives au dépistage étaient rares. Le deuxième article montre que l’auto-rapport de l’usage récent du préservatif a une très faible sensibilité lorsque comparé à l’étalon d’or que constitue la PSA. Ainsi, la plupart des personnes chez qui la PSA était retrouvée ne rapportaient aucun rapport non protégé récent. La discordance entre l’auto-rapport d’utilisation récente du préservatif et la présence de PSA était associée à une perception de risque d’infection au VIH élevé. Enfin, la troisième section montre que si l’utilisation systématique du préservatif était très fréquente avec les clients, elle l’est beaucoup moins avec le principal partenaire régulier non-client. Le désir d’enfant de la femme TS contribue de manière significative à l’utilisation non systématique du condom avec ce type de partenaire. Des facteurs sociodémographiques, comportementaux et la coinfection par d’autres IST sont associés à la présence d’IST/VIH, ces dernières étant fréquentes dans la population des femmes TS malgré les nombreuses interventions qui y sont menées. Conclusion : En conclusion, l’on peut dire que la prévention du VIH chez les femmes TS constitue un défi nécessitant des interventions intégrées tenant compte du contexte commercial dans lequel ces interventions sont implantées et des aspirations des femmes TS en matière de reproduction. / Background: Female sex workers (FSW) constitute the population most at risk for HIV infection in many countries of Sub-Saharan Africa. Several interventions have been implemented in this population to reduce the risk of infection. These interventions include the promotion of condom use and the screening and treatment of sexually transmitted infections (STI). However, some components are poorly represented among the interventions offered to FSW. Voluntary counselling and testing could be a useful intervention of primary and secondary prevention for this population but the acceptability of this intervention by FSW is little-known. In addition, in terms of surveillance of the epidemics, the evaluation of the validity of self-reported condom use is important as this indicator is frequently used in population surveys. More information is also needed about the importance of the desire for children in using inconsistently condoms with the main non-paying regular partner. Finally, the prevalence of STIs such as HPV-16 and the combined impact of sociodemographic, behavioural and preventive factors on HIV/STIs infection in this population need to be assessed. Objectives: The objectives of this thesis are 1) to measure the acceptability and the consequences of voluntary HIV counselling and testing among FSW in Conakry, Guinea; 2) to assess the validity of self-report condom use in this population through a biological indicator of semen, the prostate specific antigen (PSA); 3) to measure condom use with clients and non-client partners of FSW and to study the importance of the desire for children in inconsistent condom use with the main regular non-client partner and 4) to measure the prevalence of STIs and HIV and the socio-demographic, behavioural and preventive factors related to these infection outcomes. Methodology: We conducted a longitudinal study in the city of Conakry, Guinea among 421 FSW recruited in three health centers adapted for FSW. A longitudinal mixed design allowed for quantitative and qualitative data collections at baseline and one year later. Biological screening tests for STIs and HIV were performed. Results: The first article presented in this thesis showed that the acceptability of voluntary counselling and testing is high among FSW. The acceptance rate of testing, the return rate for results and disclosure of HIV status were close to 100%. This acceptability seemed to be the result of a high risk perception of HIV infection and of social pressure on FSW by the sex work stakeholders to undergo testing and to disclose their serostatus. Negatives consequences to VCT were rare. The second paper showed that self-reported recent condom use had a very low sensitivity when compared to the gold standard. Thus, most women in whom the PSA was found did not report any recent unprotected intercourse. The discrepancy between self-reported recent condom use and the presence of PSA was associated with a perceived high risk of HIV infection. The third section showed that while condom use was very common with clients, it was much less with non-client regular partners. The desire for pregnancy among SW contributed significantly to inconsistent condom use with this type of sexual partner. Socio-demographic characteristics, behavioural factors and co-infection with other STIs were associated with the presence of STIs and HIV, which were common despite all the interventions that were conducted in this population. Conclusion: In conclusion, HIV prevention among FSW is a challenge requiring the development of integrated strategies that take into account the commercial context in which these interventions are implemented but also FSW’s childbearing aspirations.

Introduction: Social networks have shown promise in curbing drug dependency and infectious diseases among marginalized populations. The purpose of this study is to elucidate how relationship strength in social networks is associated with risk behaviours for infectious diseases. Methods: Two reviews were conducted: 1) a systematic review exploring the association between risk behaviours and relationship strength 2) a review on the utilization of respondent driven sampling (RDS). We also analyzed network data to determine the association between recent injection drug use and recent crack use. Results: Our reviews revealed that few studies link relationship strength and risk behaviours; moreover, RDS is effective method of sampling from marginalized populations. Finally, our analysis demonstrated that close relationships are associated with drug use. Conclusion: “Close” relationships are important in arbitrating injection drug use and crack smoking. More research addressing the issues of using data from dynamic social processes and hard-to-reach populations is needed.

This study explored preparatory students’ perceptions of the risk of contracting the Human Immuno-deficiency Virus (HIV) and sexually transmitted infections (STIs) in Ethopia. It utilised a non-experimental exploratory survey methodology. A range of findings was revealed. Most respondents (67.14%) were knowledgeable about HIV/AIDS and more than half of the respondents knew about STIs. A significant number of respondents (67.1%) were able to describe HIV transmission prevention methods. Twenty one percent of respondents were sexually active and 17.0% of these reported to have used condoms. Twenty nine percent and 4.25% of the respondents had selfperceived risk of contracting HIV infection and STIs respectively. In spite of increased awareness of HIV/AIDS, school youths still engage in high-risk sexual activities and believe that they are unlikely to contract the disease. The study findings have implications for practice, and recommendations are offered for further research / Health Studies / M.A. (Public Health)

This thesis is focused on a situation of sexually transmitted infections in Prague (and in The Czech Republic shallowly) and analyzes this issue relatively to the social epidemiology. The thesis tries to identify the most vulnerable groups of a population. These groups contain homosexual men, individuals having unprotected sex and promiscuous people. Further more, the thesis tries to identify a relation between a high-risk factor and an exposition of a particular infection. For example, it was found out that sexual related risks are mostly determinated by a sexual behavior and a region where the individuals come from. Also, men are more vulnerable group of people than women according to findings of this thesis. A gonorrhoea infection is the most reported sexually transmitted infection in Prague (59,1 % of all cases). Syphilis is the second most common infection of this kind. The highest prevalence of sexually transmitted infections was reported for people with (finished or unfinished) basic education. This group of people represents 14,3 % of all reported cases. Its prevalence is 67,7 patients per ten thousand individuals. A group of people aged 20 - 29 years is another group with high prevalence. Further identification of a sexual behavior in The Czech Republic was one of the main goals of this...