Currently, the leading route of new HIV-1 infection is via heterosexual transmission, in which women are disproportionately burdened. One key factor associated with a fourfold increased risk of HIV-1 acquisition is a dysbiotic vaginal microbiota (VMB). A dysbiotic VMB is characterized by a diverse mix of anaerobic species without any appreciable amounts of beneficial Lactobacillus species. Our understanding of the species-specific manner by which vaginal bacteria interact with one another and with the host to induce susceptibility remains incompletely understood. With this, this study was designed to elucidate the interactions between common vaginal bacteria and host vaginal epithelial cells. The phenotypic and metabolic characteristics of these bacteria were also examined to provide a deeper understanding about the conditions in which each species may be able to survive and thrive. Common vaginal bacteria analyzed included dysbiosis associated species Gardnerella vaginalis and Prevotella bivia, as well as Lactobacillus species L. crispatus and L. iners. The presence of P. bivia, G. vaginalis and L. iners cocultured with vaginal epithelial cells in vitro resulted in reduced viability of vaginal epithelial cells, reduced barrier integrity and the production of pro-inflammatory cytokines. Conversely, the presence of L. crispatus did not, and was able to negate these adverse effects when placed in a dual species coculture with either of the other species. Additionally, we found that L. crispatus was the only one of these four species to produce hydrogen peroxide, and its supernatant was capable of inhibiting the growth of G. vaginalis and P. bivia. While we found that all four vaginal species could use glycogen for their growth, L. crispatus was able to use the widest range of carbohydrates tested. This translated to L. crispatus significantly outcompeting the other three bacterial species when cocultured in bacterial broth media with various carbohydrates tested. Our data provides insight into the species-specific nature by which common vaginal bacteria may interact with vaginal epithelial cells to increase host susceptibility to infection through cytotoxicity, decreased barrier function, and inflammation. We importantly observed the ability of L. crispatus to largely mitigate these effects and our phenotypic characterization place L. crispatus as the species most adept to provide protection in the FRT. Together, this work contributes to a better understanding of the interactions that govern the dynamics of the VMB and can be built upon to develop more rationale therapeutic or prophylactic interventions to improve the reproductive health of many vulnerable women. / Thesis / Master of Science (MSc)

Background: The composition of the vaginal microbiota (VMB) in the female genital tract (FGT) can impact the vaginal epithelium and protect against or increase risk of sexually transmitted viral infections. The VMB grows as a biofilm, a complex structure formed by bacteria for increased survival. When the VMB consists of a diverse bacterial community it correlates with pathogenic effects that lead to adverse health conditions and an increased risk of HIV infection. When the VMB contains Lactobacillus species, beneficial health effects and decreased susceptibility to infection are observed. The aim of this project is to optimize an in vitro model of biofilm formation for different bacteria associated with the VMB, identify the effects that biofilm has on vaginal epithelial cells and test biofilm treatment strategies. We hypothesize that a Lactobacillus biofilm will enhance barrier function and decrease cytotoxicity of vaginal epithelial cells whereas dysbiotic biofilm will decrease barrier function and induce cytotoxicity. We also hypothesize that various conditions, such as presence of estradiol and eubiotic short-chain fatty acids, will stimulate Lactobacillus biofilm growth and suppress dysbiotic biofilm growth in a vaginal epithelial cell model. Methods: For optimization of the biofilm model, VK2/E6E7 cells were grown in air-liquid interface (ALI) or liquid-liquid interface (LLI) cultures in presence or absence of L. crispatus, L. iners, G. vaginalis or P. bivia bacteria. Biofilm formation was assessed using FilmTracerTM SYPRO® Ruby biofilm matrix protein stain. Hormone effects were tested by adding estradiol (10-9 M) and progesterone (10-7 M) to culture media. Short-chain fatty acid (SCFA) effects were tested by adding lactic acid, acetic acid, succinic acid and butyric acid in varying concentrations to culture media. Enzyme effects were tested by adding sialidase to Vk2 cells before bacteria inoculation. Results: A novel in vitro model of biofilm formation on vaginal epithelial cells was created. Vk2 cells in ALI and LLI cultures remained viable in anaerobic conditions and showed mucin-1 production in aerobic and anaerobic conditions. Matrix protein staining provided a means to accurately visualize and quantify biofilm formation in this model. L. crispatus and L. iners biofilm growth maintained vaginal epithelial barrier integrity without cytotoxicity. G. vaginalis and P. bivia biofilm growth significantly reduced barrier integrity (p=0.0166, p=0.0115) and increased cytotoxicity (p=0.0024, p<0.0001). Estradiol significantly increased the growth of L. crispatus biofilm in the co-culture system (p<0.0001). Progesterone significantly increased G. vaginalis biofilm growth in the Vk2 cell co-culture (p=0.006). L. crispatus biofilm formation in the estradiol condition, G. vaginalis biofilm formation in the progesterone condition and P. bivia biofilm growth in the normal media condition were significantly decreased in the presence of sialidase (p<0.0001, p=0.0001, p=0.0380). Conclusion: A novel in vitro model of biofilm formation on a vaginal epithelial cell line that can be used to visualize and quantify biofilm growth was generated. This model was used to test various strategies for biofilm enhancement or dissociation. Estradiol enhanced beneficial Lactobacillus biofilm growth, while progesterone enhanced dysbiotic biofilm growth. Mucin- digesting enzyme sialidase was effective at dissociating all biofilms. This model can be used in the future to test different strategies of dysbiotic biofilm dissociation and enhancement of Lactobacillus biofilm in order to investigate treatments for Bacterial Vaginosis (BV) and reduce susceptibility to HIV transmission in women. / Thesis / Master of Science (MSc)

Made available in DSpace on 2016-04-28T20:17:25Z (GMT). No. of bitstreams: 1 2006-Juliana Braga de Andrade.pdf: 277168 bytes, checksum: e50d423b690ca866b106dbd90d193ab4 (MD5) Previous issue date: 2006-02-20 / In this study vaginal material was collected for microbiological and cytological evaluation in 39 female domestic cats, divided into two groups. The first group consisted of 21 whole animals, and the second of 18 neutered cats. All animals were apparently healthy, with ages varying from six months to 12 years, and were of different breeds; they came from domestic and county breeding centers in Rio de Janeiro. After mechanical containment, and cleansing of vulvar area, the proceeding for the microbiological isolation begun, for this two sterile pedriatic swabs previously embedded in a 0,9% saline solution were necessary. The first swab was used for bacterial isolation and preserved in Nutrient Agar transportation medium. The second swab was used for the fungal isolation and transported in Peptonated Water 1%. Afterwards, the material of both collections was refrigerated and sent to analysis. After this, the collection for cytological analysis was performed using a small interdental brush. The smears were fixated in absolute alcohol and dyed by the quick dyeing method (Diff Quick ?). In both groups studied differences were observed as to the number and species of bacteria. The first group had a higher frequency of Edwardsiella tarda (19,04%), followed by Enterobacter spp and Streptococcus spp, both with 17 isolations (16,19%). In relation to the neutered animals of the second group there was a higher predominance of Enterobacter spp (16,88%) and of Escherichia coli and of aeroginous Pseudomonas in the same proportion ( 14,28%). In the fungal isolation and identification it was also possible to observe differences related to the isolated ones in relation to the groups. In the first group there were 30,5% of Candida spp followed by Aspergillus spp (18,64%) and Curvularia spp (11,86%). Whereas in the second group, with castrated animals, there was a higher frequency of Penicillium spp (25%), Cladosporium (18,75%) and Candida spp (16,66%). As to the association between the microbiological and colpocytological exams it was observed that there was an agreement between the two auxiliary methods of diagnostic of vaginal microbiota of female cats only in the bacterial isolation, but not in the fungal isolation. / No presente estudo foi realizada a coleta de material vaginal para as avalia??es microbiol?gicas e citol?gicas em 39 gatas dom?sticas, divididas em dois grupos, sendo o primeiro composto de 21 animais inteiros e outro com 18 f?meas castradas, aparentemente saud?veis, com idade variando de seis meses a 12 anos, de diferentes ra?as, provenientes de cria??es domiciliares e particulares do munic?pio do Rio de Janeiro. Ap?s a conten??o mec?nica das f?meas e limpeza da regi?o vulvar, iniciou-se o procedimento para o isolamento microbiol?gico, para tal foram necess?rios dois swabs pedi?tricos est?reis, previamente umedecidos com solu??o salina est?ril a 0,9%. O primeiro swab foi utilizado para o isolamento bacteriano, sendo acondicionado em meio de transporte Agar Nutriente. O segundo swab para o isolamento f?ngico, transportado em ?gua Peptonada a 1%. Ap?s a coleta, ambos foram mantidos sob refrigera??o e encaminhados para an?lise. Em seguida procedeu-se a coleta para an?lise citol?gica com a utiliza??o da escova interdental fina. Os esfrega?os foram fixados em ?lcool absoluto e corados pelo m?todo de colora??o r?pida (Diff Quick?). Em rela??o aos dois grupos estudados observou-se diferen?as quanto ao n?mero e as esp?cies bacterianas encontradas. O primeiro grupo teve maior freq??ncia de Edwardsiella tarda (19,04%) seguido de Enterobacter spp e Streptococcus spp, ambos com 17 isolados (16,19%). Em rela??o aos animais castrados do segundo grupo, houve maior predomin?ncia de Enterobacter spp (16,88%) e de Escherichia coli e Pseudomonas aeruginosa com a mesma propor??o (14,28%). No isolamento e identifica??o f?ngica, foi poss?vel tamb?m observar diferen?as quanto aos isolados em rela??o aos grupos. No primeiro grupo houve 30,5% de Candida spp, seguido de Aspergillus spp (18,64%) e Curvularia (11,86%). No segundo grupo de animais castrados, houve maior freq??ncia de Penicillium spp (25%), Cladosporium (18,75%) e Candida spp (16,66%). Sobre a associa??o entre os exames microbiol?gicos e colpocitol?gicos, observou-se uma concord?ncia entre os dois m?todos auxiliares de diagn?stico da microbiota vaginal de gatas somente em rela??o ao isolamento bacteriano, mas n?o em rela??o ? f?ngica.

Immune activation is increasingly recognized as a critical element of HIV infection and pathogenesis, causing expansion of virus founder populations at the mucosal port of entry and eventual exhaustion of cellular immune effectors. A cohort of HIV-resistant (HIV-R) commercial sex workers (CSW) in Nairobi, Kenya, have increased levels of anti- inflammatory factors in vaginal secretions and reduced peripheral immune activation ("immune quiescence"). The mucosal immune micro-environment underlying HIV susceptibility is well-known to be influenced by concurrent sexually transmitted infections, however the role of commensal microbiota is poorly characterized. Bacterial vaginosis (BV), characterized by a shift from Lactobacillus to Gardnerella and Prevotella as dominant members of vaginal microbiota, is a risk factor for HIV acquisition in studies worldwide. However, the etiology and ecological dynamics of BV remain enigmatic, and the mechanisms by which BV increases HIV susceptibility are not fully defined. Protective functional characteristics of Lactobacillus microbiota, including acid and hydrogen peroxide (H2O2) production, may reinforce physicochemical defences of vaginal mucus, stimulate innate epithelial defences and/or modulate activation status of HIV target cells. Therefore, the goal of this study was to determine if reduced BV and increased Lactobacillus colonization are the basis for resistance to HIV in this cohort. Vaginal specimens from a group of 242 CSW were examined, including microscopic diagnosis of BV, culture-based functional analyses and phylogenetic profiling by ultra-deep sequencing. HIV-R individuals were just as likely to have BV compared to other HIV- negative (HIV-N) individuals, and no more likely to be colonized with acid- or H2O2- ii producing bacteria, however two BV-related phylotypes identified by deep sequencing were significantly more likely to be observed in HIV-N individuals (p=0.0002 and p=0.006). HIV+ individuals were significantly more likely than HIV– individuals to have E. coli detected by deep sequencing (p<0.0001) and less likely to have Lactobacillus crispatus (p=0.0006). A coherent set of differences in culture-based and culture- independent characteristics were observed in individuals with BV diagnoses compared to BV– individuals. This study has generated an unprecedented amount of information regarding the composition, structure and function of the vaginal microbiota in African CSW, fundamentally defining many aspects of BV microbiology. Elucidation of the relationship between complex microbial communities and protective mucosal responses against HIV infection should be a priority for future research.

Immune activation is increasingly recognized as a critical element of HIV infection and pathogenesis, causing expansion of virus founder populations at the mucosal port of entry and eventual exhaustion of cellular immune effectors. A cohort of HIV-resistant (HIV-R) commercial sex workers (CSW) in Nairobi, Kenya, have increased levels of anti- inflammatory factors in vaginal secretions and reduced peripheral immune activation ("immune quiescence"). The mucosal immune micro-environment underlying HIV susceptibility is well-known to be influenced by concurrent sexually transmitted infections, however the role of commensal microbiota is poorly characterized. Bacterial vaginosis (BV), characterized by a shift from Lactobacillus to Gardnerella and Prevotella as dominant members of vaginal microbiota, is a risk factor for HIV acquisition in studies worldwide. However, the etiology and ecological dynamics of BV remain enigmatic, and the mechanisms by which BV increases HIV susceptibility are not fully defined. Protective functional characteristics of Lactobacillus microbiota, including acid and hydrogen peroxide (H2O2) production, may reinforce physicochemical defences of vaginal mucus, stimulate innate epithelial defences and/or modulate activation status of HIV target cells. Therefore, the goal of this study was to determine if reduced BV and increased Lactobacillus colonization are the basis for resistance to HIV in this cohort. Vaginal specimens from a group of 242 CSW were examined, including microscopic diagnosis of BV, culture-based functional analyses and phylogenetic profiling by ultra-deep sequencing. HIV-R individuals were just as likely to have BV compared to other HIV- negative (HIV-N) individuals, and no more likely to be colonized with acid- or H2O2- ii producing bacteria, however two BV-related phylotypes identified by deep sequencing were significantly more likely to be observed in HIV-N individuals (p=0.0002 and p=0.006). HIV+ individuals were significantly more likely than HIV– individuals to have E. coli detected by deep sequencing (p<0.0001) and less likely to have Lactobacillus crispatus (p=0.0006). A coherent set of differences in culture-based and culture- independent characteristics were observed in individuals with BV diagnoses compared to BV– individuals. This study has generated an unprecedented amount of information regarding the composition, structure and function of the vaginal microbiota in African CSW, fundamentally defining many aspects of BV microbiology. Elucidation of the relationship between complex microbial communities and protective mucosal responses against HIV infection should be a priority for future research.

Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-03-27T10:38:01Z No. of bitstreams: 0 / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-03-27T14:00:10Z (GMT) No. of bitstreams: 0 / Made available in DSpace on 2018-03-27T14:00:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-03-01 / A microbiota vaginal é um ecossistema formado por bactérias aeróbias e anaeróbias, que vivem em equilíbrio dinâmico. Fatores como imunidade e variações hormonais podem provocar a perda do equilíbrio, ocasionando a proliferação de patógenos oportunistas. A vaginose bacteriana (VB) é uma doença de etiologia polimicrobiana, podendo ocorrer em associação com outros microrganismos, tais como o Papilomavirus humano (HPV). O HPV é mais prevalente na população feminina sexualmente ativa, sendo fator de risco para o desenvolvimento do câncer cervical. O objetivo do trabalho foi avaliar a diversidade microbiana do ecossistema vaginal de mulheres com e sem atipias celulares cervicais e relacionar com HPV. Fluido vaginal e raspado da cérvice uterina foram coletados (n= 33 sem lesão e n=41 com lesão) e DNA viral e bacteriano foi extraído. Lâminas foram coradas pelo método de Gram, a fim de estabelecer o escore de Nugent para avaliação da VB. Reação de PCR para genotipagem do HPV foi realizado. PCR-DGGE foi realizado para avaliação da estrutura da comunidade bacteriana. A média de idade das mulheres foi de 36 anos; compreendendo 87% (sem lesão) e 92% (com lesão). A análise do escore de Nugent revelou que 51% das mulheres com lesão não apresentavam VB e 29% eram portadoras de VB. O exame de Papanicolaou mostrou que 31% das mulheres apresentavam lesão com células escamosas atípicas de significado indeterminado (ASC-US), seguida de lesão epitelial escamosa de baixo grau (LSIL) e lesão epitelial escamosa de alto grau (HSIL), ambas com 26%, e 14% das mulheres apresentaram lesão com células escamosas atípicas que não permitem excluir lesão de alto grau (ASC-H). HPV foi detectado em 91% das pacientes, sendo identificados 5 tipos do grupo de alto risco oncogênico (16, 18, 31, 52 e 58). O HPV 16 foi o mais frequente (85%), seguido do HPV 18 (68%). No grupo sem lesão a prevalência da concomitância de HPV 16 e 18 foi de 58% e no grupo com lesão foi de 60%. Na faixa etária de 18 a 30 anos, 43% das mulheres apresentaram HPV 16, e 35% apresentaram coinfecção por HPV 16 e 18. A associação entre a genotipagem e o exame de Papanicolaou mostrou que 40% das pacientes ASC-US e 20% ASC-H apresentaram monoinfecção por HPV 16. Das mulheres com HPV 16 e coinfecção por HPV 16 e 18, VB foi encontrada em 25% das mulheres. Na análise do agrupamento obtido por PCR-DGGE observa-se, com algumas exceções, que os perfis de mulheres com as mesmas condições de saúde (normal, intermediário e com vaginose bacteriana) tenderam a se agrupar, embora em grupos separados. Na análise do agrupamento em relação às atipias, não foi observada a formação de um padrão. Dada a complexidade do ecossistema vaginal, sugere-se a necessidade de técnicas com maior poder de resolução para o entendimento da relação entre o HPV, microbiota vaginal e lesões celulares cervicais. / The vaginal microbiota is a complex ecosystem formed by aerobic and anaerobic bacteria, which live in dynamic equilibrium. Factors such as immunity and hormonal variations can cause loss of balance, leading to the proliferation of opportunistic pathogens and resulting in diseases. Bacterial vaginosis (BV) is a polymicrobial disease, and may occur in association with other microorganisms, such as Human Papillomavirus (HPV). HPV is the most prevalent in the female sexually active population, being a risk factor for the development of cervical intraepithelial lesions, which may progress to cervical cancer. The aim of this study was to evaluate the microbial diversity of the vaginal ecosystem of women with cervical cellular atypias and carrying HPV. Vaginal fluid and scraped uterine cervix were collected (n = 33 without lesion and n = 41 with lesion) and viral and bacterial DNA was extracted. Glass slides were stained by the Gram method in order to establish the Nugent score for BV evaluation. PCR reaction for HPV genotyping was performed. DGGE-PCR was performed to assess the structure of the bacterial community. The mean age of the women was 36 years; comprising 87% (without lesion) and 92% (with lesion). Analysis of the Nugent score revealed that 51% of the women with lesion did not present BV and 29% had BV. Pap smear test showed that 31% of the women had atypical squamous cells of undetermined significance (ASC-US), 26% had low grade squamous epithelial lesion (LSIL), 26% had high grade squamous epithelial lesion (HSIL) and 14% had with atypical squamous cells that do not allow the exclusion of high-grade lesion (ASC-H). HPV was detected in 91% of the patients, being identified 5 types of the high risk group (16, 18, 31, 52 and 58). HPV 16 was the most frequent (85%), followed by HPV 18 (68%). In the non-lesion group, the prevalence of HPV 16 and 18 concomitance was 58% and in the lesion group it was 60%. In the 18-30 age group, 43% of the women had HPV 16, and 35% had coinfection by HPV 16 and 18. The association between genotyping and the Pap smear showed that 40% of ASC- US patients and 20% ASC-H showed monoinfection by HPV 16. Besides, out of women with HPV 16 and coinfection by HPV 16 and 18, BV was found in 25%. In the analysis of the grouping obtained by PCR-DGGE it is observed with some exceptions, that the profiles of women with the same health conditions (healthy, intermediate and with bacterial vaginosis) tended to group, although in separate groups. Analysis of the cluster in relation to the atypia did not observe the formation of a pattern. Given the complexity of the vaginal ecosystem, it is suggested the need for higher resolution power techniques for understanding the relationship between HPV, vaginal microbiota and cervical cellular lesions.

Grâce aux avancées de la technologie et nouvelles stratégies OMICS, de nombreuses études se sont intéressées au microbiote vaginal ces dernières années. Elles ont révélé l'impact de ce dernier sur la santé de la femme. En effet, un déséquilibre de la flore vaginale la rend vulnérable, la prédisposant à la vaginose bactérienne ainsi qu’à des complications gynéco-obstétricales sévères. La pathogénèse de la vaginose reste encore méconnue et le traitement classique par antibiothérapie échoue dans plus de 50% des cas. En analysant 50 prélèvements vaginaux provenant de patientes atteintes de vaginose et de femmes saines vivant en France et au Sénégal, nous avons constaté une plus grande diversité bactérienne chez les patientes par rapport aux témoins avec l'augmentation d'espèces telles que Gardnerella vaginalis, Atopobium vaginae ainsi que les procaryotes sensibles à l'oxygène, y compris les Cocci anaérobies à Gram-positif et les Prevotella. Les femmes saines renfermaient plus d’espèces de Lactobacillaceae et de Proteobacteria dans leurs flores. La combinaison de la métagénomique et la culturomique a permis d’identifier un complexe de 11 espèces/genres bactériens associés à la vaginose. L’utilisation de la culturomique a permis d’accroître le répertoire des bactéries humaines avec l’isolement de 27 nouvelles espèces. Le faible taux de recouvrement entre les données de métagénomique et celles de culturomique montre la nécessité de persévérer dans l’isolement des bactéries par culturomique. L’obtention d'isolats permettra d'explorer in vitro les compétitions entre les bactéries et pourrait servir également de matière première pour développer un traitement par bactériothérapie / Over the last decades, thanks to the technologic progresses including advanced molecular techniques and new OMICS strategies, many studies have focused on the vaginal microbiota. Thus, revealing the impact of the vaginal flora on women health. Indeed, the disruption of the vaginal bacterial community makes it prone to bacterial vaginosis and severe obstetrical and gynecological disorders. The pathogenesis of bacterial vaginosis is still unknown, and relapses are very frequent. Conventional treatment with antibiotic therapy fails in more than 50% of cases. The analysis of 50 vaginal samples from bacterial vaginosis patients and healthy women living in France and Senegal, showed a higher bacterial diversity in patients compared to controls with the increase of species such as Gardnerella vaginalis, Atopobium vaginae as well as oxygen-sensitive prokaryotes including Gram-positive anaerobic cocci, and Prevotella spp. Healthy women harbored more Lactobacillaceae species and Proteobacteria in their microbiota. The combination of metagenomics and culturomics has allowed the identification of a complex of 11 bacterial species/genera associated with bacterial vaginosis. The use of the culturomics approach has extended the repertoire of human-associated bacteria, with the isolation of 27 new bacterial species. The low range overlap between metagenomic and culturomics data indicates the need to continue the isolation of bacteria by culturomics. Obtaining isolates will make it possible to explore in vitro the competitions between the bacteria but can also be used as primary material for the development new treatments by bacteriotherapy

The female genital tract represents the first line of defence against HIV. Biological factors such as female sex hormones, and the vaginal microbiota are known to affect HIV susceptibility at this site. The female sex hormone estradiol is known to play a protective role, whereas the progestin based contraceptive medroxyprogesterone acetate increases HIV susceptibility HIV. In addition, a Lactobacilli dominant vaginal microbiota is generally protective against HIV. Therefore, in this study, we aimed to elucidate the effects of female sex hormones, and Lactobacilli on the innate immune response of vaginal epithelial cells. / Thesis / Master of Science (MSc)

Background: Persistent infection with high risk HPV is a necessary but insufficient cause of cervical cancer. Behavioural, viral and host factors modulate the risk of HPV persistence. In this thesis, I explore the role of the vaginal microbiota, a host factor and the presence of multiple HPV infections, a viral factor in HPV persistence. Considering the limited data on the epidemiology of HPV related diseases in low and middle-countries (LMIC), and the limited success of cervical cancer screening strategies in many LMIC, I provide data on the distribution of HPV related diseases in Nigeria and evaluate the acceptability of innovative strategies to increase cervical cancer screening uptake. Methods/Results: To achieve my aims, I implemented a longitudinal cohort study of 1,020 women in Nigeria. I begin my results chapters with two methodological papers. Attrition is an important consideration for every longitudinal cohort, particularly in LMIC, therefore, I present my findings on attrition, determinants of attrition and practical strategies to ensure low attrition in studies conducted in LMIC. Considering that sexual behaviour is an important potential confounder in all HPV studies, and the reliability of self-reported history is often questioned, I present findings on the test-retest reliability of self-reported sexual behaviour history collected in my study. Having found that attrition levels were low and that self-reported sexual behaviour history was generally reliable within my cohort, I present my findings on the association between the vaginal microbiota and persistent hrHPV; and the role of multiple HPV infections in viral persistence. I found that the vaginal microbiota was associated with persistent hrHPV in HIV negative women, but not in HIV positive women; and that multiple HPV infections did not increase the risk of viral persistence when compared to single HPV infections. Next, I present my findings on the prevalence and incidence of anogenital warts in Nigeria, with additional reports on the prevalence of cervical cancer and other HPV associated cancers using data from two population based cancer registries. Finally, I present my findings on the acceptability of innovative strategies to improve cervical cancer screening uptake in Nigeria. I found that Nigerian women had a favorable attitude to the use of HPV DNA based screening as part of routine antenatal care, however attitudes towards the use of self-sampling techniques for HPV based cervical cancer screening varied by religious affiliations. Conclusion: In my thesis, I was able to systematically investigate the epidemiology of HPV infections in a LMIC. I considered the distribution of HPV related diseases, host and viral determinants of HPV persistence and investigated control strategies to reduce the burden of cervical cancer in a LMIC. My results provide useful data for surveillance, monitoring and evaluation of control programs on HPV and cervical cancer in Nigeria and may be useful to cervical cancer control programs in other LMIC.