Projections of human papillomavirus (HPV) vaccination impact in Ethiopia, India, Nigeria and Pakistan: a comparative modelling study.

INTRODUCTION: Cervical cancer is the second most common cancer among women in Ethiopia, India, Nigeria and Pakistan. Our study objective was to assess similarities and differences in vaccine-impact projections through comparative modelling analysis by independently estimating the potential health impact of human papillomavirus (HPV) vaccination. METHODS: Using two widely published models (Harvard and Papillomavirus Rapid Interface for Modelling and Economics (PRIME)) to estimate HPV vaccination impact, we simulated a vaccination scenario of 90% annual coverage among 10 cohorts of 9-year-old girls from 2021 to 2030 in Ethiopia, India, Nigeria and Pakistan. We estimated potential health impact in terms of cervical cancer cases, deaths and disability-adjusted life years averted among vaccinated cohorts from the time of vaccination until 2100. We harmonised the two models by standardising input data to comparatively estimate HPV vaccination impact. RESULTS: Prior to harmonising model assumptions, the range between PRIME and Harvard models for number of cervical cancer cases averted by HPV vaccination was: 262 000 to 2 70 000 in Ethiopia; 1 640 000 to 1 970 000 in India; 330 000 to 3 36 000 in Nigeria and 111 000 to 1 33 000 in Pakistan. When harmonising model assumptions, alignment on HPV type distribution significantly narrowed differences in vaccine-impact estimates. CONCLUSION: Despite model differences, the Harvard and PRIME models yielded similar vaccine-impact estimates. The main differences in estimates are due to variation in interpretation around data on cervical cancer attribution to HPV-16/18. As countries make progress towards WHO targets for cervical cancer elimination, continued explorations of underlying differences in model inputs, assumptions and results when examining cervical cancer prevention policy will be critical.

Lives saved with vaccination for 10 pathogens across 112 countries in a pre-COVID-19 world.

Background: Vaccination is one of the most effective public health interventions. We investigate the impact of vaccination activities for Haemophilus influenzae type b, hepatitis B, human papillomavirus, Japanese encephalitis, measles, Neisseria meningitidis serogroup A, rotavirus, rubella, Streptococcus pneumoniae, and yellow fever over the years 2000-2030 across 112 countries. Methods: Twenty-one mathematical models estimated disease burden using standardised demographic and immunisation data. Impact was attributed to the year of vaccination through vaccine-activity-stratified impact ratios. Results: We estimate 97 (95%CrI[80, 120]) million deaths would be averted due to vaccination activities over 2000-2030, with 50 (95%CrI[41, 62]) million deaths averted by activities between 2000 and 2019. For children under-5 born between 2000 and 2030, we estimate 52 (95%CrI[41, 69]) million more deaths would occur over their lifetimes without vaccination against these diseases. Conclusions: This study represents the largest assessment of vaccine impact before COVID-19-related disruptions and provides motivation for sustaining and improving global vaccination coverage in the future. Funding: VIMC is jointly funded by Gavi, the Vaccine Alliance, and the Bill and Melinda Gates Foundation (BMGF) (BMGF grant number: OPP1157270 / INV-009125). Funding from Gavi is channelled via VIMC to the Consortium's modelling groups (VIMC-funded institutions represented in this paper: Imperial College London, London School of Hygiene and Tropical Medicine, Oxford University Clinical Research Unit, Public Health England, Johns Hopkins University, The Pennsylvania State University, Center for Disease Analysis Foundation, Kaiser Permanente Washington, University of Cambridge, University of Notre Dame, Harvard University, Conservatoire National des Arts et Métiers, Emory University, National University of Singapore). Funding from BMGF was used for salaries of the Consortium secretariat (authors represented here: TBH, MJ, XL, SE-L, JT, KW, NMF, KAMG); and channelled via VIMC for travel and subsistence costs of all Consortium members (all authors). We also acknowledge funding from the UK Medical Research Council and Department for International Development, which supported aspects of VIMC's work (MRC grant number: MR/R015600/1).JHH acknowledges funding from National Science Foundation Graduate Research Fellowship; Richard and Peggy Notebaert Premier Fellowship from the University of Notre Dame. BAL acknowledges funding from NIH/NIGMS (grant number R01 GM124280) and NIH/NIAID (grant number R01 AI112970). The Lives Saved Tool (LiST) receives funding support from the Bill and Melinda Gates Foundation.This paper was compiled by all coauthors, including two coauthors from Gavi. Other funders had no role in study design, data collection, data analysis, data interpretation, or writing of the report. All authors had full access to all the data in the study and had final responsibility for the decision to submit for publication.

Health gains and financial protection from human papillomavirus vaccination in Ethiopia: findings from a modelling study.

High out-of-pocket (OOP) medical expenses for cervical cancer (CC) can lead to catastrophic health expenditures (CHEs) and medical impoverishment in many low-resource settings. There are 32 million women at risk for CC in Ethiopia, where CC screening is extremely limited. An evaluation of the population health and financial risk protection benefits, and their distributional consequences across socioeconomic groups, from human papillomavirus (HPV) vaccination will be critical to support CC prevention efforts in this setting. We used a static cohort model that captures the main features of HPV vaccines and population demographics to project health and economic outcomes associated with routine HPV vaccination in Ethiopia. Health outcomes included the number of CC cases, and costs included vaccination and operational costs in 2015 US dollars over the years 2019-2118 and CC treatment costs over the lifetimes of cohorts eligible for vaccination in Ethiopia. We estimated the household OOP medical expenditures averted (assuming 68% of direct medical expenditures were financed OOP) and cases of CHE averted. A case of CHE was defined as 40% of household consumption expenditures, and the cases of CHE averted depended on wealth quintile, disease incidence, healthcare use and OOP payments. Our analysis shows that, assuming 100% vaccine efficacy against HPV-16/18 and 50% vaccination coverage, routine HPV vaccination could avert up to 970 000 cases of CC between 2019 and 2118, which translates to ∼932 000 lives saved. Additionally, routine HPV vaccination could avert 33 900 cases of CHE. Approximately one-third of health benefits would accrue to the poorest wealth quintile, whereas 50% of financial risk protection benefits would accrue to this quintile. HPV vaccination can reduce disparities in CC incidence, mortality and household health expenditures. This understanding and our findings can help policymakers in decisions regarding targeted CC control efforts and investment in a routine HPV vaccination programme following an initial catch-up programme.

Estimating the health impact of vaccination against ten pathogens in 98 low-income and middle-income countries from 2000 to 2030: a modelling study.

BACKGROUND: The past two decades have seen expansion of childhood vaccination programmes in low-income and middle-income countries (LMICs). We quantify the health impact of these programmes by estimating the deaths and disability-adjusted life-years (DALYs) averted by vaccination against ten pathogens in 98 LMICs between 2000 and 2030. METHODS: 16 independent research groups provided model-based disease burden estimates under a range of vaccination coverage scenarios for ten pathogens: hepatitis B virus, Haemophilus influenzae type B, human papillomavirus, Japanese encephalitis, measles, Neisseria meningitidis serogroup A, Streptococcus pneumoniae, rotavirus, rubella, and yellow fever. Using standardised demographic data and vaccine coverage, the impact of vaccination programmes was determined by comparing model estimates from a no-vaccination counterfactual scenario with those from a reported and projected vaccination scenario. We present deaths and DALYs averted between 2000 and 2030 by calendar year and by annual birth cohort. FINDINGS: We estimate that vaccination of the ten selected pathogens will have averted 69 million (95% credible interval 52-88) deaths between 2000 and 2030, of which 37 million (30-48) were averted between 2000 and 2019. From 2000 to 2019, this represents a 45% (36-58) reduction in deaths compared with the counterfactual scenario of no vaccination. Most of this impact is concentrated in a reduction in mortality among children younger than 5 years (57% reduction [52-66]), most notably from measles. Over the lifetime of birth cohorts born between 2000 and 2030, we predict that 120 million (93-150) deaths will be averted by vaccination, of which 58 million (39-76) are due to measles vaccination and 38 million (25-52) are due to hepatitis B vaccination. We estimate that increases in vaccine coverage and introductions of additional vaccines will result in a 72% (59-81) reduction in lifetime mortality in the 2019 birth cohort. INTERPRETATION: Increases in vaccine coverage and the introduction of new vaccines into LMICs have had a major impact in reducing mortality. These public health gains are predicted to increase in coming decades if progress in increasing coverage is sustained. FUNDING: Gavi, the Vaccine Alliance and the Bill & Melinda Gates Foundation.

Long-Term Progression of Sensorineural Hearing Loss and Tinnitus after Combined Intensity-Modulated Radiation Therapy and Cisplatin-Based Chemotherapy for Nasopharyngeal Carcinoma: A Case Report.

Sensorineural hearing loss (SNHL) is a common adverse effect for nasopharyngeal carcinoma (NPC) patients treated with chemoradiotherapy. We report a case of 12-year follow-up from a patient with stage IIB NPC, treated in 2004 with intensity-modulated radiotherapy and cisplatin-based chemotherapy. Pure-tone audiograms were conducted before treatment and at two other points in the 12-year period after treatment. Analysis of the patient's audiograms reveals that the development of high-frequency SNHL started after treatment and reached a plateau accompanied by tinnitus approximately 32 months after treatment conclusion. After the plateau, high-frequency SNHL continued to develop slowly in the next 10 years, possibly a long-term effect from radiation-induced microvascular change of the hearing apparatus. The continuous high-frequency hearing decline is associated with increased tinnitus pitch in the patient. With experience learned from this case, we recommend hearing tests at regular intervals for at least 3-5 years for NPC patients treated with chemoradiotherapy. Patients need to be educated about tinnitus and counseling can be offered when they begin to feel inconvenienced by tinnitus. These patients also need to be advised against exposure to noise that can aggravate the already compromised hearing apparatus, leading to further hearing loss and worsening tinnitus. Limiting the peak dose and total cumulative dose of cisplatin should be considered based on the patients' risk factors to achieve a balance between treatment efficacy and long-term adverse effects.

Estimated economic impact of vaccinations in 73 low- and middle-income countries, 2001-2020.

OBJECTIVE: To estimate the economic impact likely to be achieved by efforts to vaccinate against 10 vaccine-preventable diseases between 2001 and 2020 in 73 low- and middle-income countries largely supported by Gavi, the Vaccine Alliance. METHODS: We used health impact models to estimate the economic impact of achieving forecasted coverages for vaccination against Haemophilus influenzae type b, hepatitis B, human papillomavirus, Japanese encephalitis, measles, Neisseria meningitidis serogroup A, rotavirus, rubella, Streptococcus pneumoniae and yellow fever. In comparison with no vaccination, we modelled the costs - expressed in 2010 United States dollars (US$) - of averted treatment, transportation costs, productivity losses of caregivers and productivity losses due to disability and death. We used the value-of-a-life-year method to estimate the broader economic and social value of living longer, in better health, as a result of immunization. FINDINGS: We estimated that, in the 73 countries, vaccinations given between 2001 and 2020 will avert over 20 million deaths and save US$ 350 billion in cost of illness. The deaths and disability prevented by vaccinations given during the two decades will result in estimated lifelong productivity gains totalling US$ 330 billion and US$ 9 billion, respectively. Over the lifetimes of the vaccinated cohorts, the same vaccinations will save an estimated US$ 5 billion in treatment costs. The broader economic and social value of these vaccinations is estimated at US$ 820 billion. CONCLUSION: By preventing significant costs and potentially increasing economic productivity among some of the world's poorest countries, the impact of immunization goes well beyond health.

Model-based impact and cost-effectiveness of cervical cancer prevention in the Extended Middle East and North Africa (EMENA).

To date, no studies have evaluated the cost-effectiveness of human papillomavirus (HPV) vaccination in countries in the Extended Middle East and North Africa (EMENA) region. We synthesized population and epidemiologic data for 20 EMENA countries using a model-based approach to estimate averted cervical cancer cases and deaths, disability-adjusted life years (DALYs) and cost-effectiveness ratios (I$ [international dollars] per DALY averted) associated with HPV vaccination of pre-adolescent girls. We utilized additional epidemiologic data from Algeria, Lebanon, and Turkey to evaluate select cervical cancer screening strategies either alone or in combination with vaccination. Results showed that pre-adolescent vaccination of five consecutive birth cohorts at 70% coverage has the potential to prevent over 180,000 cervical cancer cases. Cases averted varied by country, largely due to differences in cancer burden and population size; 69% of cases averted occurred in the three GAVI-eligible countries in EMENA. Despite the low cervical cancer incidence in EMENA, we found that HPV vaccination was cost-effective using a threshold of each country's gross domestic product per capita (a common metric for evaluating cost-effectiveness) in all but five countries at a cost per vaccinated girl of I$25 ($5 per dose). However, cost-effectiveness diminished with increasing vaccine cost; at a cost of I$200 per vaccinated girl, HPV vaccination was cost-effective in only five countries. When the cost per vaccinated girl exceeded I$50 in Lebanon and Turkey and I$150 in Algeria, screening alone was most attractive. We identified opportunities to improve upon current national screening guidelines, involving less frequent screening every 3-5 years. While pre-adolescent HPV vaccination promises to be a cost-effective strategy in most EMENA countries at low costs, decision makers will need to consider many other factors, such as affordability, acceptability, feasibility, and competing health priorities, when making decisions about cervical cancer prevention. This article forms part of a regional report entitled "Comprehensive Control of HPV Infections and Related Diseases in the Extended Middle East and North Africa Region" Vaccine Volume 31, Supplement 6, 2013. Updates of the progress in the field are presented in a separate monograph entitled "Comprehensive Control of HPV Infections and Related Diseases" Vaccine Volume 30, Supplement 5, 2012.

The estimated mortality impact of vaccinations forecast to be administered during 2011-2020 in 73 countries supported by the GAVI Alliance.

INTRODUCTION: From August to December 2011, a multidisciplinary group with expertise in mathematical modeling was constituted by the GAVI Alliance and the Bill & Melinda Gates Foundation to estimate the impact of vaccination in 73 countries supported by the GAVI Alliance. METHODS: The number of deaths averted in persons projected to be vaccinated during 2011-2020 was estimated for ten antigens: hepatitis B, yellow fever, Haemophilus influenzae type B (Hib), Streptococcus pneumoniae, rotavirus, Neisseria meningitidis serogroup A, Japanese encephalitis, human papillomavirus, measles, and rubella. Impact was calculated as the difference in the number of deaths expected over the lifetime of vaccinated cohorts compared to the number of deaths expected in those cohorts with no vaccination. Numbers of persons vaccinated were based on 2011 GAVI Strategic Demand Forecasts with projected dates of vaccine introductions, vaccination coverage, and target population size in each country. RESULTS: By 2020, nearly all GAVI-supported countries with endemic disease are projected to have introduced hepatitis B, Hib, pneumococcal, rotavirus, rubella, yellow fever, N. meningitidis serogroup A, and Japanese encephalitis-containing vaccines; 55 (75 percent) countries are projected to have introduced human papillomavirus vaccine. Projected use of these vaccines during 2011-2020 is expected to avert an estimated 9.9 million deaths. Routine and supplementary immunization activities with measles vaccine are expected to avert an additional 13.4 million deaths. Estimated numbers of deaths averted per 1000 persons vaccinated were highest for first-dose measles (16.5), human papillomavirus (15.1), and hepatitis B (8.3) vaccination. Approximately 52 percent of the expected deaths averted will be in Africa, 27 percent in Southeast Asia, and 13 percent in the Eastern Mediterranean. CONCLUSION: Vaccination of persons during 2011-2020 in 73 GAVI-eligible countries is expected to have substantial public health impact, particularly in Africa and Southeast Asia, two regions with high mortality. The actual impact of vaccination in these countries may be higher than our estimates because several widely used antigens were not included in the analysis. The quality of our estimates is limited by lack of data on underlying disease burden and vaccine effectiveness against fatal disease outcomes in developing countries. We plan to update the estimates annually to reflect updated demand forecasts, to refine model assumptions based on results of new information, and to extend the analysis to include morbidity and economic benefits.

Comparative evaluation of the potential impact of rotavirus versus HPV vaccination in GAVI-eligible countries: a preliminary analysis focused on the relative disease burden.

BACKGROUND: Immunization policymakers at global and local levels need to establish priorities among new vaccines competing for limited resources. However, comparison of the potential impact of single vaccination programs is challenging, primarily due to the limited number of vaccine analyses as well as their differing analytic approaches and reporting formats. The purpose of this study is to provide early insight into how the comparative impact of different new vaccines could be assessed in resource-poor settings with respect to affordability, cost-effectiveness, and distributional equity. METHODS: We compared the health, economic, and financial consequences of introducing the two vaccines in 72 GAVI-eligible countries using a number of different outcome measures to evaluate affordability, cost-effectiveness, and distributional equity. We use simple static models to standardize the analytic framework and improve comparability between the two new vaccines. These simple models were validated by leveraging previously developed, more complex models for rotavirus and human papillomavirus (HPV). RESULTS: With 70% coverage of a single-age cohort of infants and pre-adolescent girls, the lives saved with rotavirus (~274,000) and HPV vaccines (~286,000) are similar, although the timing of averted mortality differs; rotavirus-attributable deaths occur in close proximity to infection, while HPV-related cancer deaths occur largely after age 30. Deaths averted per 1000 vaccinated are 5.2 (rotavirus) and 12.6 (HPV). Disability-adjusted life years (DALYs) averted were ~7.15 million (rotavirus) and ~1.30 million (HPV), reflecting the greater influence of discounting on the latter, given the lagtime between vaccination and averted cancer. In most countries (68 for rotavirus and 66 for HPV, at the cost of I$25 per vaccinated individual) the incremental cost per DALY averted was lower than each country's GDP per capita. Financial resources required for vaccination with rotavirus are higher than with HPV since both genders are vaccinated. CONCLUSIONS: While lifesaving benefits of rotavirus and HPV vaccines will be realized at different times, the number of lives saved over each target populations' lifetimes will be similar. Model-based analyses that use a standardized analytic approach and generate comparable outputs can enrich the priority-setting dialogue. Although new vaccines may be deemed cost-effective, other factors including affordability and distributional equity need to be considered in different settings. We caution that for priority setting in an individual country, more rigorous comparisons should be performed, using more comprehensive models and considering all relevant vaccines and delivery strategies.

Health and economic outcomes of HPV 16,18 vaccination in 72 GAVI-eligible countries.

The risk of dying from cervical cancer is disproportionately borne by women in developing countries. Two new vaccines are highly effective in preventing HPV 16,18 infection, responsible for approximately 70% of cervical cancer, in girls not previously infected. The GAVI Alliance (GAVI) provides technical assistance and financial support for immunization in the world's poorest countries. Using population-based and epidemiologic data for 72 GAVI-eligible countries we estimate averted cervical cancer cases and deaths, disability-adjusted years of life (DALYs) averted and incremental cost-effectiveness ratios (I$/DALY averted) associated with HPV 16,18 vaccination of young adolescent girls. In addition to vaccine coverage and efficacy, relative and absolute cancer reduction depended on underlying incidence, proportion attributable to HPV types 16 and 18, population age-structure and competing mortality. With 70% coverage, mean reduction in the lifetime risk of cancer is below 40% in some countries (e.g., Nigeria, Ghana) and above 50% in others (e.g., India, Uganda, Kenya). At I$10 per vaccinated girl (approximately $2.00 per dose assuming three doses, plus wastage, administration, program support) vaccination was cost-effective in all countries using a per capita GDP threshold; for 49 of 72 countries, the cost per DALY averted was less than I$100 and for 59 countries, it was less than I$200. Taking into account country-specific assumptions (per capita GNI, DPT3 coverage, percentage of girls who are enrolled in fifth grade) for the year of introduction, percent coverage achieved in the first year, and years to maximum coverage, a 10-year modeled scenario prevented the future deaths of approximately 2 million women vaccinated as adolescents. Despite favorable cost-effectiveness, assessment of financial costs raised concerns about affordability; as the cost per vaccinated girl was increased from I$10 to I$25 (approximately $2 to $5 per dose), the financial costs for the 10-year scenario increased from >US$ 900 million to US$ 2.25 billion. Provided high coverage of young adolescent girls is feasible, and vaccine costs are lowered, HPV 16,18 vaccination could be very cost-effective even in the poorest countries, and provide comparable value for resources to other new vaccines such as rotavirus.