Human Papillomavirus Vaccination in South Africa: Programmatic Challenges and Opportunities for Integration With Other Adolescent Health Services?

A systematic literature review of human papillomavirus vaccination strategies in delivery systems within national and regional immunization programs

The uptake of human papillomavirus (HPV) vaccine remains suboptimal despite being a part of routine vaccination within national immunization program(s). This indicates probable challenges with the implementation of HPV immunization program(s) in various countries. The objective of this systematic literature review (SLR) was to identify implementation strategies for HPV vaccination within national and regional immunization programs worldwide with an aim to provide guidance for countries targeting to increase their HPV vaccine coverage rate (VCR). A comprehensive literature search was conducted across Medline and Embase and included articles published between January 2012 and January 2022. Of the 2,549 articles retrieved, 168 met inclusion criteria and were included in the review. Strategies shown to improve HPV vaccination uptake in the reviewed literature include campaigns to increase community awareness and knowledge of HPV, health care provider trainings, integrating HPV vaccination within school settings, coordinated efforts via multi-sectoral partnerships, and vaccination reminder and recall systems. Findings may help national authorities understand key considerations for HPV vaccination when designing and implementing programs aiming to increase HPV VCR in adolescents.

Human Papillomavirus Vaccination Acceleration and Introduction in Sub-Saharan Africa: A Multi-Country Cohort Analysis

BACKGROUND

Cervical cancer, caused by human papillomavirus (HPV) infection, is the second-largest cancer killer of women in low- and middle-income countries. The brunt of the global burden is borne predominantly in Sub-Saharan Africa. In 2020 alone, 70,000 of the 100,000 infected women in Africa died from it, thereby making up 21% of global cervical cancer mortality. The introduction of the HPV vaccine into the National Immunization Program was expected to change the trajectory. However, uptake of the vaccination has been poor, especially for the second dose. Only about half of the countries in Africa currently provide the vaccine. Without urgent intervention, the 2030 global cervical cancer elimination targets will be undermined. The study aims to understand the key challenges facing the HPV vaccine and to develop a roadmap to accelerate the uptake.

METHOD

Fourteen countries were purposively included using a cohort design methodology and the investigation spanned March-July 2023. The Africa region was stratified into three focus-group discussion cohorts (Abidjan, Nairobi and Dar es Salaam), comprising pre-selected countries that have already and those about to introduce the HPV vaccine. In each country, the EPI manager, the NITAG chair or representatives and an HPV-focal researcher were selected participants. The methods involved a collaborative and knowledge-sharing format through regional and country-specific discussions, plenary discussions, and workshop-style group missions.

RESULTS

The study reached a total of 78 key stakeholders, comprising 30 participants in cohort one, 21 in cohort two and 27 in cohort three. Key outcomes included the prevalence of declining HPV2 vaccination across all countries in the region; country-specific barriers impeding uptake were identified and strategy for accelerating vaccination demand initiated, e.g., utilizing investments from COVID-19 (e.g., electronic registry and multisector coordination); individual countries developing their respective HPV vaccination recovery and acceleration roadmaps; the identification and inclusion of a zero-dose catch-up strategy into the vaccination roadmaps; support for a transition from multiple-doses to a single-dose HPV vaccine; the incorporation of implementation science research to support the decision-making process such as vaccine choices, doses and understanding behavior.

CONCLUSION

Beyond research, the study shows the significance of scientific approaches that are not limited to understanding problems, but are also solution-oriented, e.g., development of roadmaps to overcome barriers against HPV vaccination uptake.

Cost-effectiveness of single-visit cervical cancer screening in KwaZulu-Natal, South Africa: a model-based analysis accounting for the HIV epidemic

Introduction

Women living with human immunodeficiency virus (WLHIV) face elevated risks of human papillomavirus (HPV) acquisition and cervical cancer (CC). Coverage of CC screening and treatment remains low in low-and-middle-income settings, reflecting resource challenges and loss to follow-up with current strategies. We estimated the health and economic impact of alternative scalable CC screening strategies in KwaZulu-Natal, South Africa, a region with high burden of CC and HIV.

Methods

We parameterized a dynamic compartmental model of HPV and HIV transmission and CC natural history to KwaZulu-Natal. Over 100 years, we simulated the status quo of a multi-visit screening and treatment strategy with cytology and colposcopy triage (South African standard of care) and six single-visit comparator scenarios with varying: 1) screening strategy (HPV DNA testing alone, with genotyping, or with automated visual evaluation triage, a new high-performance technology), 2) screening frequency (once-per-lifetime for all women, or repeated every 5 years for WLHIV and twice for women without HIV), and 3) loss to follow-up for treatment. Using the Ministry of Health perspective, we estimated costs associated with HPV vaccination, screening, and pre-cancer, CC, and HIV treatment. We quantified CC cases, deaths, and disability-adjusted life-years (DALYs) averted for each scenario. We discounted costs (2022 US dollars) and outcomes at 3% annually and calculated incremental cost-effectiveness ratios (ICERs).

Results

We projected 69,294 new CC cases and 43,950 CC-related deaths in the status quo scenario. HPV DNA testing achieved the greatest improvement in health outcomes, averting 9.4% of cases and 9.0% of deaths with one-time screening and 37.1% and 35.1%, respectively, with repeat screening. Compared to the cost of the status quo ($12.79 billion), repeat screening using HPV DNA genotyping had the greatest increase in costs. Repeat screening with HPV DNA testing was the most effective strategy below the willingness to pay threshold (ICER: $3,194/DALY averted). One-time screening with HPV DNA testing was also an efficient strategy (ICER: $1,398/DALY averted).

Conclusions

Repeat single-visit screening with HPV DNA testing was the optimal strategy simulated. Single-visit strategies with increased frequency for WLHIV may be cost-effective in KwaZulu-Natal and similar settings with high HIV and HPV prevalence.

The Acceptability of Pharmacy-Based HPV Vaccination in Western Kenya among Pharmacy Clients and Providers

Vaccine coverage for the human papillomavirus (HPV) remains low globally, and differentiated models of vaccine delivery are needed to expand access. Pharmacy-based models of the HPV vaccination may engage women who could benefit. We assessed the acceptability of such a model among pharmacy clients and providers at 20 private pharmacies in Kisumu County, Kenya. In questionnaires, participants (≥18 years) were asked the extent they agreed (5-point scale) with statements that assessed different acceptability component constructs outlined in the Theoretical Framework of Acceptability (TFA). From March to June 2022, 1500 pharmacy clients and 40 providers were enrolled and completed questionnaires. Most clients liked the intervention (TFA: affective attitude; 96%, 1435/1500) and did not think it would be hard to obtain (TFA: burden; 93%, 1399/1500). All providers agreed the intervention could reduce HPV infection (TFA: perceived effectiveness) and felt confident they could deliver it (TFA: self-efficacy). Among the clients who had received or were planning to receive the HPV vaccine in the future, half (50%, 178/358) preferred a pharmacy-based HPV vaccination. In this study, most Kenyan pharmacy clients and providers perceived a pharmacy-delivered HPV vaccination as highly acceptable; however, more research is needed to test the feasibility and effectiveness of this novel vaccine delivery model in Africa.

A scoping review on integrated health campaigns for immunization in low- and middle-income countries

Health campaign integration is a key implementation strategy outlined by the World Health Organization to achieve universal health coverage. This scoping review synthesizes the evidence on Integrated Health Campaigns (IHC) in the field of immunization in low- and middle-income countries (LMICs) regarding the most common strategies, facilitators and barriers. Four reviewers followed a systematic approach to identify, screen and analyse relevant articles. The team used three search engines (PubMed, Scopus and Google Scholar) to identify peer-reviewed journal articles as well as select institutional websites for grey literature publications. Full-text articles using any study design and across any time frame were included. Data were extracted following a predefined matrix, analysed deductively and presented in a narrative synthesis. Thirty articles (20 academic and 10 grey) were included in the final review. All studies included identified IHCs as effective when planning or implementation is integrated. The common strategies were: using resources efficiently in remote locations; using national immunization days to maximize impact; targeting specific age groups by selecting intervention sites that are frequented by that age group; building community ownership over the integrated program; and integrating programs that already share common elements. The key facilitators were: closing the gap between services and communities; planning, coordination and resource management both before and during integration; cost-effectiveness; and utilization of pre-existing infrastructure. The common barriers included seemingly optimized initial cost to appear feasible only in the short term and additional responsibilities on the field staff. This review finds IHCs a common practice in immunization and identifies gaps in evidence on evaluation; indicating the need for additional research. Strong evidence accounts IHCs to increase coverage, improve community acceptance of health services and strengthen the community models of health service delivery.

Factors associated with uptake of human papillomavirus vaccination among adolescent girls in Mettu town, southwest Ethiopia: a school-based cross-sectional study

OBJECTIVE

This study was designed to assess the level of uptake of human papillomavirus (HPV) vaccination and its associated factors among school-age adolescent girls.

DESIGN

School-based cross-sectional study.

SETTING

High schools in Mettu town, southwest Ethiopia, from 5 February to 10 March 2022.

PARTICIPANTS

Data were collected using a pretested and structured questionnaire through face-to-face interviews with 667 adolescent girls selected via multistage random sampling. Data were entered into EpiData V.3.1 and exported to SPSS V.26 for analysis. Simple binary logistic regression was done, and variables with a p value less than 0.25 were entered into a multivariable logistic regression model; variables with a p value <0.05 were considered significant.

RESULTS

About half (48.6%) of adolescent girls aged 14-18 years had received the HPV vaccine. Being in the 16-18 years age group (adjusted OR 2.7, 95% CI 1.50 to 4.80), having good knowledge (2.14, 95% CI 1.29 to 3.52), having a positive attitude (5.86, 95% CI 3.51 to 9.76), and getting encouragement from healthcare workers (3.04, 95% CI 1.36 to 6.79), teachers (2.14, 95% CI 1.05 to 4.34) and parents (2.39, 95% CI 1.02 to 5.64) were significantly associated with vaccine uptake.

CONCLUSION

The uptake of HPV vaccination was low. Having good knowledge and positive attitude as well as encouragement from parents, healthcare workers and teachers were identified as factors associated with HPV vaccine uptake. Improving knowledge about HPV and involving teachers and parents in the immunisation campaign might help promote HPV vaccine uptake.

Poor Cervical Cancer Knowledge and Awareness among Women and Men in the Eastern Cape Province Rural Community

Cervical cancer knowledge and awareness is low among South Africans despite high cervical cancer prevalence. This study aimed to investigate knowledge about the symptoms, signs, risk factors, and methods of prevention of cervical cancer among women and men in the rural Eastern Cape province, South Africa. This cross-sectional analytical study was conducted in the rural community of the OR Tambo municipality in the Eastern Cape province. 252 women and men aged ≥ 25 years were randomly recruited. Data were collected using semi-structured questionnaires. A knowledge score was categorized as "good" if it was ≥65%. The majority of participants (69.8%) were women. Only a proportion of 25.6% (51/199) of the participants had good overall knowledge about cervical cancer, and the majority of these (84.3%) were women. Women previously screened for cervical cancer had a significantly higher median cervical knowledge score than those who had never been screened (p = 0.002). Only among women, good knowledge about cervical cancer was associated with a tertiary education level (OR: 3.17, 95% CI: 1.08-9.57, p = 0.044) and high household income (OR: 3.40, 95% CI: 1.24-9.75, p = 0.027). Both women and men in rural Eastern Cape had limited knowledge about the risk factors and prevention methods of cervical cancer. Public health strategies to improve knowledge and awareness of cervical cancer among both men and women are necessary.

Uptake of human papillomavirus vaccination and its associated factors among adolescents in Gambella town, Southwest, Ethiopia: a community-based cross-sectional study

OBJECTIVE

To assess the uptake of human papillomavirus (HPV) vaccination and its associated factors among adolescents in Gambella town, Southwest Ethiopia.

DESIGN

A community-based cross-sectional study.

SETTING

Gambella town, Southwest Ethiopia.

PARTICIPANTS

A total of 882 adolescents were included between May and July 2022.

OUTCOME

Uptake of HPV vaccination.

METHODS

A cluster sampling technique was used to select study participants. An interviewer-administered and pretested questionnaire was used to collect the data. The collected data were entered into Epi-data V.4.6 and exported to STATA V.16 for cleaning, coding and analysis. A binary logistic regression model was used to test the association between independent and dependent variables. Variables with a p<0.05 in the multivariable logistic regression were considered statistically significant factors for the uptake of HPV vaccination.

RESULTS

A total of 825 adolescents participated in this study. Among participants, 48% (95% CI 44.6% to 51.4%) have been vaccinated for HPV. Ever heard of the HPV vaccine (AOR 2.5, 95% CI 1.23 to 5.08), good knowledge of HPV infection (AOR 3.62, 95% CI 2.17 to 6.02), good knowledge of the HPV vaccine (AOR 5.54, 95% CI 3.28 to 9.36) and attitude towards the HPV vaccine (AOR 2.74, 95% CI 1.88 to 3.98) were significantly associated HPV vaccination.

CONCLUSION

In the current study, the uptake of HPV vaccination was found to be low. The finding highlights the importance of promoting community health education about HPV infection and vaccines and providing behaviour change education, which plays a substantial role in promoting the uptake of HPV vaccination.

Human Papillomavirus Epidemiology and Prevention: Is There Still a Gender Gap?

BACKGROUND AND AIM

Human papillomavirus (HPV) is sexually transmitted, one of the three most common sexually transmitted infections (STIs) in both males and females, and the most common viral STI. A crucial public health strategy to protect people against HPV is vaccination, which has shown its effectiveness in preventing HPV-related diseases. Presently, three types of vaccines are available (bivalent, quadrivalent, and nonvalent), and they all target the two most oncogenic virus genotypes (HPV 16 and 18). In recent years, the need to implement vaccination programmes that include all genders has been discussed in order to achieve herd immunity against HPV. To date, only a few countries have included young males in their vaccination programmes. Thus, our objective with this review is to provide an overview of the epidemiology of HPV and HPV prevention strategies and report the latest findings from the scientific literature.

Barriers and facilitators of HPV vaccination in sub-saharan Africa: a systematic review

BACKGROUND

Human Papilloma Virus (HPV) is the most common sexually transmitted infection worldwide. Globally, both men and women have a 50% risk of being infected at least once in their life. HPV prevalence is among the highest in sub-Saharan Africa (SSA), at an average of 24%. HPV causes different types of cancers, including cervical cancer (CC), which is the leading cause of cancer deaths among women in SSA. HPV-vaccination has been proven to be effective in reducing HPV induced cancers. SSA countries are delayed in reaching the WHO's target of fully vaccinating 90% of girls within the age of 15 by 2030. Our systematic review aims to identify barriers and facilitators of HPV-vaccination in SSA to inform national implementation strategies in the region.

METHODS

This is a mixed method systematic review based on the PRISMA statement and The Joanna Briggs Institute Reviewers' Manual. Search strategies were adapted to each selected database: PubMed/MEDLINE, Livivo, Google Scholar, Science Direct, and African Journals Online for papers published in English, Italian, German, French and Spanish between 1 December 2011 and 31 December 2021. Zotero and Rayyan were the software used for data management. The appraisal was conducted by three independent reviewers.

RESULTS

A total of 20 articles were selected for appraisal from an initial 536 articles. Barriers included: limited health system capacities, socio-economic status, stigma, fear and costs of vaccines, negative experience with vaccinations, COVID-19 pandemic, lack of correct information, health education (HE) and consent. Additionally, we found that boys are scarcely considered for HPV-vaccination by parents and stakeholders. Facilitators included: information and knowledge, policy implementation, positive experience with vaccinations, HE, stakeholders' engagement, women's empowerment, community engagement, seasonality, and target-oriented vaccination campaigns.

CONCLUSIONS

This review synthesizes barriers and facilitators of HPV-vaccinations in SSA. Addressing these can contribute to the implementation of more effective HPV immunization programs targeted at eliminating CC in line with the WHO 90/70/90 strategy.

REGISTRATION AND FUNDING

Protocol ID: CRD42022338609 registered in the International Prospective Register of Systematic Reviews (PROSPERO). Partial funds: German Centre for Infection research (DZIF) project NAMASTE: 8,008,803,819.

Projections of human papillomavirus vaccination and its impact on cervical cancer using the Caputo fractional derivative

We propose a fractional order model for human papillomavirus (HPV) dynamics, including the effects of vaccination and public health education on developing cervical cancer. First, we discuss the general structure of Caputo fractional derivatives and integrals. Next, we define the fractional HPV model using Caputo derivatives. The model equilibrium quantities, with their stability, are discussed based on the magnitude of the reproduction number. We compute and simulate numerical solutions of the presented fractional model using the Adams-Bashforth-Moulton scheme. Meanwhile, real data sourced from reports from the World Health Organization is used to establish the parameters and compute the basic reproduction number. We present figures of state variables for different fractional orders and the classical integer order. The impacts of vaccination and public health education are discussed through numerical simulations. From the results, we observe that an increase in both vaccination rates and public health education increases the quality of life, and thus, reduces disease burden and suffering in communities. The results also confirm that modeling HPV transmission dynamics using fractional derivatives includes history effects in the model, making the model further insightful and appropriate for studying HPV dynamics.

The population impact of herpes simplex virus type 2 (HSV-2) vaccination on the incidence of HSV-2, HIV and genital ulcer disease in South Africa: a mathematical modelling study

BACKGROUND

Evidence suggests HSV-2 infection increases HIV acquisition risk and HIV/HSV-2 coinfection increases transmission risk of both infections. We analysed the potential impact of HSV-2 vaccination in South Africa, a high HIV/HSV-2 prevalence setting.

METHODS

We adapted a dynamic HIV transmission model for South Africa to incorporate HSV-2, including synergistic effects with HIV, to evaluate the impact of: (i) cohort vaccination of 9-year-olds with a prophylactic vaccine that reduces HSV-2 susceptibility; (ii) vaccination of symptomatically HSV-2-infected individuals with a therapeutic vaccine that reduces HSV shedding.

FINDINGS

An 80% efficacious prophylactic vaccine offering lifetime protection with 80% uptake could reduce HSV-2 and HIV incidence by 84.1% (95% Credibility Interval: 81.2-86.0) and 65.4% (56.5-71.6) after 40 years, respectively. This reduces to 57.4% (53.6-60.7) and 42.1% (34.1-48.1) if efficacy is 50%, 56.1% (53.4-58.3) and 41.5% (34.2-46.9) if uptake is 40%, and 29.4% (26.0-31.9) and 24.4% (19.0-28.7) if protection lasts 10 years. An 80% efficacious therapeutic vaccine offering lifetime protection with 40% coverage among symptomatic individuals could reduce HSV-2 and HIV incidence by 29.6% (21.8-40.9) and 26.4% (18.5-23.2) after 40 years, respectively. This reduces to 18.8% (13.7-26.4) and 16.9% (11.7-25.3) if efficacy is 50%, 9.7% (7.0-14.0) and 8.6% (5.8-13.4) if coverage is 20%, and 5.4% (3.8-8.0) and 5.5% (3.7-8.6) if protection lasts 2 years.

INTERPRETATION

Prophylactic and therapeutic vaccines offer promising approaches for reducing HSV-2 burden and could have important impact on HIV in South Africa and other high prevalence settings.

FUNDING

WHO, NIAID.

Malignancy and viral infections in Sub-Saharan Africa: A review

The burden of malignancy related to viral infection is increasing in Sub-Saharan Africa (SSA). In 2018, approximately 2 million new cancer cases worldwide were attributable to infection. Prevention or treatment of these infections could reduce cancer cases by 23% in less developed regions and about 7% in developed regions. Contemporaneous increases in longevity and changes in lifestyle have contributed to the cancer burden in SSA. African hospitals are reporting more cases of cancer related to infection (e.g., cervical cancer in women and stomach and liver cancer in men). SSA populations also have elevated underlying prevalence of viral infections compared to other regions. Of 10 infectious agents identified as carcinogenic by the International Agency for Research on Cancer, six are viruses: hepatitis B and C viruses (HBV and HCV, respectively), Epstein-Barr virus (EBV), high-risk types of human papillomavirus (HPV), Human T-cell lymphotropic virus type 1 (HTLV-1), and Kaposi's sarcoma herpesvirus (KSHV, also known as human herpesvirus type 8, HHV-8). Human immunodeficiency virus type 1 (HIV) also facilitates oncogenesis. EBV is associated with lymphomas and nasopharyngeal carcinoma; HBV and HCV are associated with hepatocellular carcinoma; KSHV causes Kaposi's sarcoma; HTLV-1 causes T-cell leukemia and lymphoma; HPV causes carcinoma of the oropharynx and anogenital squamous cell cancer. HIV-1, for which SSA has the greatest global burden, has been linked to increasing risk of malignancy through immunologic dysregulation and clonal hematopoiesis. Public health approaches to prevent infection, such as vaccination, safer injection techniques, screening of blood products, antimicrobial treatments and safer sexual practices could reduce the burden of cancer in Africa. In SSA, inequalities in access to cancer screening and treatment are exacerbated by the perception of cancer as taboo. National level cancer registries, new screening strategies for detection of viral infection and public health messaging should be prioritized in SSA's battle against malignancy. In this review, we discuss the impact of carcinogenic viruses in SSA with a focus on regional epidemiology.

Knowledge on Cervical Cancer Services and Associated Risk Factors by Health Workers in the Eastern Cape Province

Globally, cancer is a leading cause of death, with cervical cancer ranking second among all cancers. Its adversity impacts not only individuals but also families, societies, and governments. The quality of services, as informed by the knowledge and adequacy of the health workers, plays an important role in both prevention, diagnosis, and management of the disease. A cross-sectional study among 108 purposively selected health workers in rural health facilities in the Eastern Cape province was conducted to assess knowledge on cervical cancer and associated risk factors through the use of validated structured questionnaires. The Statistical Package for Social Sciences was used for analysis, with a 95% confidence interval and a p-value of 0.05 considered significant. A total of 91.7% of the 108 participants were female, and 25% were over the age of 50. A total of 88% and 85.2% indicated sexually transmitted disease and human immunodeficiency virus as major risk factors, respectively. The HPV, pap smear, and vaccination age were known by 64.8%, and vaccine availability was known by 71.3%. Only 40.7% of workers were trained on cervical screening, and 35.2% were trained on the interpretation of pap smear results. An overall knowledge score of 53% was obtained, with more experienced clinicians scoring lower grades. This study identified inadequacies in essential knowledge for successful implementation of cervical cancer services and found that extensive training was needed.

Key decision-making factors for human papillomavirus (HPV) vaccine program introduction in low-and-middle-income-countries: Global and national stakeholder perspectives

Low-and-middle-income countries (LMICs) experience a high burden of cervical cancer. The human papillomavirus (HPV) vaccine prevents high-risk strains of HPV that cause cervical cancer; however, the integration of HPV vaccines into national immunization programs within many LMICs has been suboptimal. Our study evaluated key factors that drive the decision-making process for the implementation of HPV vaccine programs in LMICs. Stakeholder analysis and semi-structured in-depth interviews were conducted with national and global stakeholders. Interview data were analyzed through qualitative descriptive methods. Findings from our study revealed the decision-making process for HPV vaccines requires the involvement of multiple institutions and stakeholders from national and global levels, with decision-making being a country-specific process. Partner considerations, locally driven processes, availability of data, and infrastructure and resource considerations were found to be critical factors in the decision-making process. Future programs should evaluate the best approaches for investing in initiatives to enhance coordination, ensure vaccine introduction is locally driven, increase the availability of data needed for decision-making, and equip countries with the necessary resources to guide country decision-making in the face of increasingly complex decision-making environments.

Population-Based Temporal Trends and Ethnic Disparity in Cervical Cancer Mortality in South Africa (1999-2018): A Join Point and Age-Period-Cohort Regression Analyses

Cervical cancer is one of the leading causes of cancer deaths among women in low- and middle-income countries such as South Africa. The current impact of national cervical cancer control and sexual and reproductive health interventions in South Africa reduce its burden. The aim of this study was to assess the trends in cervical cancer mortality and its relation to breast and gynaecological cancers in South Africa from 1999 to 2018. We conducted joinpoint regression analyses of the trends in crude and age-standardised mortality rates (ASMR) for cervical cancer mortality in South Africa from 1999 to 2018. An age−period−cohort regression analysis was also conducted to determine the impact of age, period, and cohort on cervical cancer mortality trends. Analyses were stratified by ethnicity. Cervical cancer (n = 59,190, 43.92%, 95% CI: 43.65−44.18%) was responsible for about 43.9% of breast and gynecological cancer deaths. The mortality rate of cervical cancer (from 11.7 to 14.08 per 100,000) increased at about 0.9% per annum (Average Annual Percent Change (AAPC): 0.9% (AAPC: 0.9%, p-value < 0.001)), and young women aged 25 to 49 years (AAPC: 1.2−3.5%, p-value < 0.001) had increased rates. The risk of cervical cancer mortality increased among successive birth cohorts. In 2018, cervical cancer mortality rate among Blacks (16.74 per 100,000 women) was about twice the rates among Coloureds (8.53 deaths per 100,000 women) and approximately four-fold among Indians/Asians (4.16 deaths per 100,000 women), and Whites (3.06 deaths per 100,000 women). Cervical cancer control efforts should be enhanced in South Africa and targeted at ethnic difference, age, period, and cohort effects.

Estimating the effect of HIV on cervical cancer elimination in South Africa: Comparative modelling of the impact of vaccination and screening

Background

In 2020, the World Health Organization (WHO) launched its initiative to eliminate cervical cancer as a public health problem. To inform global efforts for countries with high HIV and cervical cancer burden, we assessed the impact of human papillomavirus (HPV) vaccination and cervical cancer screening and treatment in South Africa, on cervical cancer and the potential for achieving elimination before 2120, considering faster HPV disease progression and higher cervical cancer risk among women living with HIV(WLHIV) and HIV interventions.

Methods

Three independent transmission-dynamic models simulating HIV and HPV infections and disease progression were used to predict the impact on cervical cancer incidence of three scenarios for all women: 1) girls' vaccination (9-14 years old), 2) girls' vaccination plus 1 lifetime cervical screen (at 35 years), and 3) girls' vaccination plus 2 lifetime cervical screens (at 35 and 45 years) and three enhanced scenarios for WLHIV: 4) vaccination of young WLHIV aged 15-24 years, 5) three-yearly cervical screening of WLHIV aged 15-49 years, or 6) both. Vaccination assumed 90% coverage and 100% lifetime protection with the nonavalent vaccine (against HPV-16/18/31/33/45/52/58). Cervical cancer screening assumed HPV testing with uptake increasing from 45% (2023), 70% (2030) to 90% (2045+). We also assumed that UNAIDS 90-90-90 HIV treatment and 70% male circumcision targets are reached by 2030. We examined three elimination thresholds: age-standardised cervical cancer incidence rates below 4 or 10 per 100,000 women-years, and >85% reduction in cervical cancer incidence rate. We conducted sensitivity analyses and presented the median age-standardised predictions of outcomes of the three models (minimum-maximum across models).

Findings

Girls' vaccination could reduce age-standardised cervical cancer incidence from a median of 47.6 (40.9-79.2) in 2020 to 4.5 (3.2-6.3) per 100,000 women-years by 2120, averting on average ∼4% and ∼46% of age-standardised cumulative cervical cancer cases over 25 and 100 years, respectively, compared to the basecase. Adding 2 lifetime screens helped achieve elimination over the century among all women (2120 cervical cancer incidence: 3.6 (1.9-3.6) per 100,000 women-years), but not among WLHIV (10.8 (5.3-11.6)), and averted more cumulative cancer cases overall (∼45% over 25 years and ∼61% over 100 years compared to basecase) than girls' vaccination alone. Adding three-yearly cervical screening among WLHIV (to girls' vaccination and 2 lifetime cervical screens) further reduced age-standardised cervical cancer incidence to 3.3 (1.8-3.6) per 100,000 women-years overall and to 5.2 (3.9-8.5) among WLHIV by 2120 and averted on average 12-13% additional cumulative cancer cases among all women and 21-24% among WLHIV than girls' vaccination and 2 lifetime cervical screens over 25 years or longer. Long-term vaccine protection and using the nonavalent vaccine was required for elimination.

Interpretation

High HPV vaccination coverage of girls and 2 lifetime cervical screens could eliminate cervical cancer among women overall in South Africa by the end of the century and substantially decrease cases among all women and WLHIV over the short and medium term. Cervical cancer elimination in WLHIV would likely require enhanced prevention strategies for WLHIV. Screening of WLHIV remains an important strategy to reduce incidence and alleviate disparities in cervical cancer burden between women with and without HIV, despite HIV interventions scale-up.

Funding

World Health Organization. National Cancer Institute, National Institutes of Health. MRC Centre for Global Infectious Disease Analysis, UK Medical Research Council. National Institute of Child Health and Human Development research. Cancer Association of South Africa. Canadian Institutes of Health Research and the Fonds de recherche du Québec - Santé research.

Understanding the public health value and defining preferred product characteristics for therapeutic human papillomavirus (HPV) vaccines: World Health Organization consultations, October 2021-March 2022

The World Health Organization (WHO) global strategy to eliminate cervical cancer (CxCa) could result in >62 million lives saved by 2120 if strategy targets are reached and maintained: 90% of adolescent girls receiving prophylactic human papillomavirus (HPV) vaccine, 70% of women receiving twice-lifetime cervical cancer screening, and 90% of cervical pre-cancer lesions and invasive CxCa treated. However, the cost and complexity of CxCa screening and treatment approaches has hampered scale-up, particularly in low- and middle-income countries (LMICs), and new approaches are needed. Therapeutic HPV vaccines (TxV), which could clear persistent high-risk HPV infection and/or cause regression of pre-cancerous lesions, are in early clinical development and might offer one such approach. During October 2021 to March 2022, WHO, in collaboration with the Bill and Melinda Gates Foundation, convened a series of global expert consultations to lay the groundwork for understanding the potential value of TxV in the context of current CxCa prevention efforts and for defining WHO preferred product characteristics (PPCs) for TxV. WHO PPCs describe preferences for vaccine attributes that would help optimize vaccine value and use in meeting the global public health need. This paper reports on the main discussion points and findings from the expert consultations. Experts identified several ways in which TxV might address challenges in current CxCa prevention programmes, but emphasized that the potential value of TxV will depend on their degree of efficacy and how quickly they can be developed and implemented relative to ongoing scale-up of existing interventions. Consultation participants also discussed potential use-cases for TxV, important PPC considerations (e.g., vaccine indications, target populations, and delivery strategies), and critical modelling needs for predicting TxV impact and cost-effectiveness.