Tropical Medicine & International Health

Adolescent Health Series: HPV infection and vaccination in sub‐Saharan Africa: 10 years of research in Tanzanian female adolescents ‐ narrative review

SummaryCervical cancer is the leading cause of cancer‐related morbidity and mortality in many sub‐Saharan African (SSA) countries, including Tanzania. Most cervical cancer cases worldwide are attributable to infection of the cervix with Human Papillomavirus (HPV), a vaccine‐preventable sexually transmitted infection (STI). Over the past 10 years, we have conducted a programme of HPV research in pre‐adolescents and adolescents in Mwanza, the second‐largest city in Tanzania, which is situated in a malaria‐endemic region. In this narrative review article, we summarise the contribution of our work, alongside work of others, to improve the understanding of HPV epidemiology in SSA and development of setting‐appropriate, evidence‐based intervention strategies. We present evidence for very high prevalence and incidence of HPV infection among female SSA adolescents around the time of sexual debut, describe risk factors for HPV acquisition, and discuss associations between HPV, HIV and other STIs, which are also highly prevalent within this population. We summarise findings from early clinical trials of HPV vaccines in SSA, the first of which was an immunogenicity and safety trial conducted in Mwanza, Tanzania, and Dakar, Senegal. Within the trial, we evaluated for the first time the potential impact of malaria and helminth infection on vaccine‐induced antibody responses in Tanzanian girls. We describe research evaluating optimal HPV vaccine delivery strategies within this setting, perceived requirements for and barriers to vaccine implementation among key informants from LMIC, vaccine acceptability among girls and parents, and opportunities for co‐delivery of interventions alongside HPV vaccination to an adolescent population. Finally, we discuss country‐level barriers to vaccine uptake in LMIC, and ongoing studies in Tanzania and other SSA countries of reduced‐dose HPV vaccination schedules that may alleviate cost and logistical barriers to vaccine implementation.

A health decision analytical model to evaluate the cost‐effectiveness of female genital schistosomiasis screening strategies: The female genital schistosomiasis SCREEN framework

AbstractFemale genital schistosomiasis is a chronic gynaecological disease caused by the waterborne parasite Schistosoma (S.) haematobium. It affects an estimated 30–56 million girls and women globally, mostly in sub‐Saharan Africa where it is endemic, and negatively impacts their sexual and reproductive life. Recent studies found evidence of an association between female genital schistosomiasis and increased prevalence of HIV and cervical precancer lesions. Despite the large population at risk, the burden and impact of female genital schistosomiasis are scarcely documented, resulting in neglect and insufficient resource allocation. There is currently no standardised method for individual or population‐based female genital schistosomiasis screening and diagnosis which hinders accurate assessment of disease burden in endemic countries. To optimise financial allocations for female genital schistosomiasis screening, it is necessary to explore the cost‐effectiveness of different strategies by combining cost and impact estimates. Yet, no economic evaluation has explored the value for money of alternative screening methods. This paper describes a novel application of health decision analytical modelling to evaluate the cost‐effectiveness of different female genital schistosomiasis screening strategies across endemic settings. The model combines a decision tree for female genital schistosomiasis screening strategies, and a Markov model for the natural history of cervical cancer to estimate the cost per disability‐adjusted life‐years averted for different screening strategies, stratified by HIV status. It is a starting point for discussion and for supporting priority setting in a data‐sparse environment.

The burden of travelling for cervical cancer treatment in Uganda: A mixed‐method study

AbstractBackgroundUganda has one of the highest rates of cervical cancer in the world. Many women are diagnosed and treated with advanced stages of the disease. With only one facility offering comprehensive cervical cancer care in Uganda, many women are required to travel significant distances and spend time away from their homes to receive cervical cancer care. It is important to understand the burden of time away from home while attending treatment because it can inform the expansion of cervical cancer treatment programmes. The aim of this mixed‐methods paper is to describe how the distance to cervical cancer treatment locations impacts women in Uganda.MethodsWomen were recruited from 19 September, 2022, to 17 January, 2023, at the Uganda Cancer Institute (UCI) and the cancer clinic at Jinja Regional Referral Hospital (JRRF). Women were eligible for the study if they were (i) aged ≥18 years with a histopathologic diagnosis of cervical cancer; (ii) being treated at the UCI or JRRF for cervical cancer; and (iii) able to provide consent to participate in the study in English, Luganda, Lusoga, Luo, or Runyankole. All participants completed a quantitative survey and a selected group was sampled for semi‐structured interviews. Data were analysed using the convergent parallel mixed‐methods approach. Descriptive statistics were reported for the quantitative data and qualitative data using an inductive‐deductive thematic analysis approach.ResultsIn all, 351 women participated in the quantitative section of the study and 24 in the qualitative. The quantitative and qualitative findings largely aligned and supported one another. Women reported travelling up to 14 h to receive treatment and 20% noted that they would spend three or more nights away from home during their current visit. Major themes of the qualitative include means of transportation, spending the night away from home, and financial factors.ConclusionOur findings show that travelling to obtain cervical cancer care can be a significant burden for women in Uganda. Approaches should be considered to reduce this burden such as additional satellite cervical cancer clinics or subsidised transportation options.

Association of TP53 rs1042522 with cervical cancer in the sub‐Saharan African population: a meta‐analysis

AbstractObjectiveTP53 plays a crucial role in preventing cancer development. Previous studies in sub‐Saharan Africa (SSA) reported inconclusive findings for the association of the TP53 rs1042522 C > G variant with cervical cancer. We therefore performed a meta‐analysis to summarise this association in the SSA population.MethodsOnline databases were searched to identify suitable articles according to the PRISMA guidelines. We included studies published in English or French that provided the sample sizes and genotype counts for both cases and controls and evaluated the association between TP53 rs1042522 and cervical cancer in the SSA population. A fixed‐effect model was used to calculate the pooled odds ratio (OR) and 95% confidence intervals (95% CIs).ResultsA total of 699 cervical cancer cases and 1008 controls from eight studies in SSA were included in this meta‐analysis. Women harbouring the variant G allele of the TP53 rs1042522 were at increased risk of cervical cancer in allelic (G vs. C; OR = 1.30, 95% Cl = 1.12–1.50), homozygous (GG vs. CC; OR = 1.62, 95% CI = 1.20–2.19) and recessive (GG vs. CG + GG; OR = 1.74, 95% CI = 1.34–2.25) genetic models. However, the dominant genetic model (CG + GG vs. CC; OR = 1.20, 95% CI = 0.96–1.48) was not significantly associated with cervical cancer.ConclusionsOur meta‐analysis revealed that harbouring variant G allele of TP53 rs1042522 is associated with cervical cancer risk in the SSA population.