1
|
Kim M, Kim E. Effective vaccination strategies for human papillomavirus (HPV) infection and cervical cancer based on the mathematical model with a stochastic process. J Med Virol 2024; 96:e29558. [PMID: 38533898 DOI: 10.1002/jmv.29558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 03/04/2024] [Accepted: 03/12/2024] [Indexed: 03/28/2024]
Abstract
Human papillomavirus (HPV) infection poses a significant risk to women's health by causing cervical cancer. In addition to HPV, cervical cancer incidence rates can be influenced by various factors, including human immunodeficiency virus and herpes, as well as screening policy. In this study, a mathematical model with stochastic processes was developed to analyze HPV transmission between genders and its subsequent impact on cervical cancer incidence. The model simulations suggest that both-gender vaccination is far more effective than female-only vaccination in preventing an increase in cervical cancer incidence. With increasing stochasticity, the difference between the number of patients in the vaccinated group and the number in the nonvaccinated group diminishes. To distinguish the patient population distribution of the vaccinated from the nonvaccinated, we calculated effect size (Cohen's distance) in addition to Student's t-test. The model analysis suggests a threshold vaccination rate for both genders for a clear reduction of cancer incidence when significant stochastic factors are present.
Collapse
Affiliation(s)
- Minsoo Kim
- Natural Product Informatics Research Center, Korea Institute of Science and Technology, Gangneung, Republic of Korea
| | - Eunjung Kim
- Natural Product Informatics Research Center, Korea Institute of Science and Technology, Gangneung, Republic of Korea
| |
Collapse
|
2
|
Saldaña F, Steindorf V, Srivastav AK, Stollenwerk N, Aguiar M. Optimal vaccine allocation for the control of sexually transmitted infections. J Math Biol 2023; 86:75. [PMID: 37058156 PMCID: PMC10103681 DOI: 10.1007/s00285-023-01910-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 03/10/2023] [Accepted: 03/31/2023] [Indexed: 04/15/2023]
Abstract
The burden of sexually transmitted infections (STIs) poses a challenge due to its large negative impact on sexual and reproductive health worldwide. Besides simple prevention measures and available treatment efforts, prophylactic vaccination is a powerful tool for controlling some viral STIs and their associated diseases. Here, we investigate how prophylactic vaccines are best distributed to prevent and control STIs. We consider sex-specific differences in susceptibility to infection, as well as disease severity outcomes. Different vaccination strategies are compared assuming distinct budget constraints that mimic a scarce vaccine stockpile. Vaccination strategies are obtained as solutions to an optimal control problem subject to a two-sex Kermack-McKendrick-type model, where the control variables are the daily vaccination rates for females and males. One important aspect of our approach relies on conceptualizing a limited but specific vaccine stockpile via an isoperimetric constraint. We solve the optimal control problem via Pontryagin's Maximum Principle and obtain a numerical approximation for the solution using a modified version of the forward-backward sweep method that handles the isoperimetric budget constraint in our formulation. The results suggest that for a limited vaccine supply ([Formula: see text]-[Formula: see text] vaccination coverage), one-sex vaccination, prioritizing females, appears to be more beneficial than the inclusion of both sexes into the vaccination program. Whereas, if the vaccine supply is relatively large (enough to reach at least [Formula: see text] coverage), vaccinating both sexes, with a slightly higher rate for females, is optimal and provides an effective and faster approach to reducing the prevalence of the infection.
Collapse
Affiliation(s)
- Fernando Saldaña
- BCAM- Basque Center for Applied Mathematics, Basque Country, Spain.
| | | | | | - Nico Stollenwerk
- BCAM- Basque Center for Applied Mathematics, Basque Country, Spain
- Dipartimento di Matematica, Universita̧ degli Studi di Trento, Povo, Italy
| | - Maíra Aguiar
- BCAM- Basque Center for Applied Mathematics, Basque Country, Spain
- Dipartimento di Matematica, Universita̧ degli Studi di Trento, Povo, Italy
- Ikerbasque, Basque Foundation for Science, Basque Country, Spain
| |
Collapse
|
3
|
Masjedi MR, Soltanizadeh N, Ainy E. Perspectives of Medical Experts' on Health Culture for Human Papillomavirus (HPV) Vaccination Compared to Auxiliary Health Workers. Asian Pac J Cancer Prev 2022; 23:4093-4097. [PMID: 36579990 PMCID: PMC9971468 DOI: 10.31557/apjcp.2022.23.12.4093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND AND OBJECTIVES The viewpoints of Shahid Beheshti University of Medical Sciences medical experts'' were compared with those of auxiliary health workers regarding health culture related to human papillomavirus vaccination in 2020. METHODS In this cross-sectional study, 220 medical experts' (gynecologists, cultural, psychological, infectious, dermatological, and educational) and auxiliary health workers were randomly selected and investigated. The required data were collected using a researcher-made questionnaire modeled on international questionnaires. These questionnaire contained demographic information on the subjects' age and sex as well as health culture was also assessed by measuring the knowledge, attitude, and practice of the subjects. RESULTS The mean age of the included medical experts' and auxiliary health workers was 38.0 3±8.3 and 35.2±7.5 years old, respectively. There was a significant difference in the knowledge of auxiliary health workers as 55.3 ± 3.8 in comparison with the medical experts' as 51.6 3± 6.3 (p <0.002). There was a significant difference on whether changing cultural attitudes about the need for vaccination could be effective on reducing sexually transmitted diseases between the auxiliary health workers and medical experts' (p <0.001). There was a significant difference in the knowledge of auxiliary health workers 55.3 ± 3.8 in comparison with the psychology and cultural experts' as 48.5± 6.3, 48.3± 6.8 (p<0.001) respectively. CONCLUSION Knowledge among the auxiliary health workers was significantly different from that of psychology and cultural experts' in relation to health culture for human papillomavirus vaccination. It was indicated that these experts need to upgrade their health culture knowledge to increase the rate of community participation in human papillomavirus vaccination.
Collapse
Affiliation(s)
- Mohammad Reza Masjedi
- Cancer Control Research Center, Cancer Control Foundation, Iran University of Medical Sciences, Tehran, Iran. ,Tobacco Control Research Center (TCRC), Iranian Anti-tobacco Association, Iran University of Medical Sciences, Tehran, Iran. ,Department of pulmonary medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Narges Soltanizadeh
- PhD in Cultural Management and Planning, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Elaheh Ainy
- Associate Professor, Safety Promtion and Injury Prevention Research Center of Shahid Beheshti University of Medical Sciences, Tehran, Iran. ,For Correspondence:
| |
Collapse
|
4
|
Gao S, Martcheva M, Miao H, Rong L. The impact of vaccination on human papillomavirus infection with disassortative geographical mixing: a two-patch modeling study. J Math Biol 2022; 84:43. [PMID: 35482215 DOI: 10.1007/s00285-022-01745-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 12/29/2021] [Accepted: 03/31/2022] [Indexed: 11/28/2022]
Abstract
Human papillomavirus (HPV) infection can spread between regions. What is the impact of disassortative geographical mixing on the dynamics of HPV transmission? Vaccination is effective in preventing HPV infection. How to allocate HPV vaccines between genders within each region and between regions to reduce the total infection? Here we develop a two-patch two-sex model to address these questions. The control reproduction number [Formula: see text] under vaccination is obtained and shown to provide a critical threshold for disease elimination. Both analytical and numerical results reveal that disassortative geographical mixing does not affect [Formula: see text] and only has a minor impact on the disease prevalence in the total population given the vaccine uptake proportional to the population size for each gender in the two patches. When the vaccine uptake is not proportional to the population size, sexual mixing between the two patches can reduce [Formula: see text] and mitigate the consequence of disproportionate vaccine coverage. Using parameters calibrated from the data of a case study, we find that if the two patches have the same or similar sex ratios, allocating vaccines proportionally according to the new recruits in two patches and giving priority to the gender with a smaller recruit rate within each patch will bring the maximum benefit in reducing the total prevalence. We also show that a time-variable vaccination strategy between the two patches can further reduce the disease prevalence. This study provides some quantitative information that may help to develop vaccine distribution strategies in multiple regions with disassortative mixing.
Collapse
Affiliation(s)
- Shasha Gao
- Department of Mathematics, University of Florida, Gainesville, FL, 32611, USA
| | - Maia Martcheva
- Department of Mathematics, University of Florida, Gainesville, FL, 32611, USA.
| | - Hongyu Miao
- Department of Biostatistics and Data Science, University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Libin Rong
- Department of Mathematics, University of Florida, Gainesville, FL, 32611, USA.
| |
Collapse
|
5
|
Gao S, Martcheva M, Miao H, Rong L. A two-sex model of human papillomavirus infection: Vaccination strategies and a case study. J Theor Biol 2022; 536:111006. [PMID: 35007512 DOI: 10.1016/j.jtbi.2022.111006] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 08/10/2021] [Accepted: 01/03/2022] [Indexed: 12/31/2022]
Abstract
Vaccination is effective in preventing human papillomavirus (HPV) infection. It still remains debatable whether males should be included in a vaccination program and unclear how to allocate the vaccine in genders to achieve the maximum benefits. In this paper, we use a two-sex model to assess HPV vaccination strategies and use the data from Guangxi Province in China as a case study. Both mathematical analysis and numerical simulations show that the basic reproduction number, an important indicator of the transmission potential of the infection, achieves its minimum when the priority of vaccination is given to the gender with a smaller recruit rate. Given a fixed amount of vaccine, splitting the vaccine evenly usually leads to a larger basic reproduction number and a higher prevalence of infection. Vaccination becomes less effective in reducing the infection once the vaccine amount exceeds the smaller recruit rate of the two genders. In the case study, we estimate the basic reproduction number is 1.0333 for HPV 16/18 in people aged 15-55. The minimal bivalent HPV vaccine needed for the disease prevalence to be below 0.05% is 24050 per year, which should be given to females. However, with this vaccination strategy it would require a very long time and a large amount of vaccine to achieve the goal. In contrast with allocating the same vaccine amount every year, we find that a variable vaccination strategy with more vaccine given in the beginning followed by less vaccine in later years can save time and total vaccine amount. The variable vaccination strategy illustrated in this study can help to better distribute the vaccine to reduce the HPV prevalence. Although this work is for HPV infection and the case study is for a province in China, the model, analysis and conclusions may be applicable to other sexually transmitted diseases in other regions or countries.
Collapse
Affiliation(s)
- Shasha Gao
- Department of Mathematics, University of Florida, Gainesville, FL 32611, United States
| | - Maia Martcheva
- Department of Mathematics, University of Florida, Gainesville, FL 32611, United States.
| | - Hongyu Miao
- Department of Biostatistics and Data Science, University of Texas Health Science Center at Houston, TX 77030, United States
| | - Libin Rong
- Department of Mathematics, University of Florida, Gainesville, FL 32611, United States.
| |
Collapse
|
6
|
Qendri V, Bogaards JA, Baussano I, Lazzarato F, Vänskä S, Berkhof J. The cost-effectiveness profile of sex-neutral HPV immunisation in European tender-based settings: a model-based assessment. Lancet Public Health 2020; 5:e592-e603. [PMID: 33120045 DOI: 10.1016/s2468-2667(20)30209-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 08/27/2020] [Accepted: 09/10/2020] [Indexed: 01/06/2023]
Abstract
BACKGROUND In many European countries, human papillomavirus (HPV) vaccine uptake among girls has remained below target levels, supporting the scope for vaccination of boys. We aimed to investigate if sex-neutral HPV vaccination can be considered cost-effective compared with girls-only vaccination at uptake levels equal to those among girls and under tender-based vaccination costs achieved throughout Europe. METHODS We investigated the cost-effectiveness of sex-neutral HPV vaccination in European tender-based settings. We applied a Bayesian synthesis framework for health economic evaluation to 11 countries (Austria, Belgium, Croatia, Estonia, Italy, Latvia, the Netherlands, Poland, Slovenia, Spain, and Sweden), accommodating country-specific information on key epidemiological and economic parameters, and on current HPV vaccination programmes. We used projections from three independently developed HPV transmission models to tailor region-specific herd effects. The main outcome measures in the comparison of sex-neutral with girls-only vaccination were cancer cases prevented and incremental cost-effectiveness ratios (ICERs), defined as the cost in international dollars (I$) per life-year gained. FINDINGS The total number of cancer cases to be prevented by vaccinating girls at currently realised vaccine uptake varied from 318 (95% CI 197-405) per cohort of 200 000 preadolescents (100 000 girls plus 100 000 boys) in Croatia (under 20% uptake of the 9-valent vaccine) to 1904 (1741-2101) in Estonia (under 70% uptake of the 9-valent vaccine). Vaccinating boys at equal coverage increased these respective numbers by 168 (95% CI 121-213) in Croatia and 467 (391-587) in Estonia. Sex-neutral vaccination was likely to be cost-effective, with ICERs of sex-neutral compared with girls-only vaccination varying from I$4300 per life-year gained in Latvia (95% credibility interval 3450-5160; 40% uptake) to I$25 720 per life-year gained in Spain (21 380-30 330; 80% uptake). At uniform 80% uptake, a favourable cost-effectiveness profile was retained for most of the countries investigated (Austria, Belgium, Italy, Latvia, the Netherlands, Slovenia, Spain, and Sweden). INTERPRETATION Sex-neutral HPV vaccination is economically attractive in European tender-based settings. However, tendering mechanisms need to ensure that vaccination of boys will remain cost-effective at high vaccine uptake rates. FUNDING European Commission 7th Framework Programme and WHO.
Collapse
Affiliation(s)
- Venetia Qendri
- Department of Epidemiology and Data Science, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Public Health, Amsterdam, Netherlands.
| | - Johannes A Bogaards
- Department of Epidemiology and Data Science, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Public Health, Amsterdam, Netherlands; Centre for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, Netherlands
| | | | - Fulvio Lazzarato
- Unit of Cancer Epidemiology, AOU Cittá della Salute e della Scienza, Hospital of Turin, Turin, Italy
| | - Simopekka Vänskä
- Infectious Disease Control and Vaccination Unit, Department of Health Security, Finnish Institute for Health and Welfare, Helsinki, Finland
| | - Johannes Berkhof
- Department of Epidemiology and Data Science, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Public Health, Amsterdam, Netherlands
| |
Collapse
|
7
|
Cost-effectiveness analysis of a gender-neutral human papillomavirus vaccination program in the Netherlands. Vaccine 2020; 38:4687-4694. [DOI: 10.1016/j.vaccine.2020.05.031] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 05/07/2020] [Accepted: 05/11/2020] [Indexed: 12/20/2022]
|
8
|
Bogaards JA, Mooij SH, Xiridou M, Schim van der Loeff MF. Potential effectiveness of prophylactic HPV immunization for men who have sex with men in the Netherlands: A multi-model approach. PLoS Med 2019; 16:e1002756. [PMID: 30830901 PMCID: PMC6398832 DOI: 10.1371/journal.pmed.1002756] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 01/31/2019] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Men who have sex with men (MSM) are at high risk for anal cancer, primarily related to human papillomavirus genotype 16 (HPV16) infections. At 8.5 per 100,000 per year, the incidence rate of anal cancer among MSM is similar to that of cervical cancer among adult women in the Netherlands. However, MSM are not included in most HPV vaccination programs. We explored the potential effectiveness of prophylactic immunization in reducing anogenital HPV16 transmission among MSM in the Netherlands. METHODS AND FINDINGS We developed a range of mathematical models for penile-anal HPV16 transmission, varying in sexual contact structure and natural history of infection, to provide robust and plausible predictions about the effectiveness of targeted vaccination. Models were informed by an observational cohort study among MSM in Amsterdam, 2010-2013. Parameters on sexual behavior and HPV16 infections were obtained by fitting the models to data from 461 HIV-negative study participants, considered representative of the local MSM population. We assumed 85% efficacy of vaccination against future HPV16 infections as reported for HIV-negative MSM, and age-specific uptake rates similar to those for hepatitis B vaccination among MSM in the Netherlands. Targeted vaccination was contrasted with vaccination of 12-year-old boys at 40% uptake in base-case scenarios, and we also considered the effectiveness of a combined strategy. Offering vaccine to MSM without age restrictions resulted in a model-averaged 27.3% reduction (90% prediction interval [PI] 11.9%-37.5%) in prevalence of anal HPV16 infections, assuming similar uptake among MSM as achieved for hepatitis B vaccination. The predicted reduction improved to 46.1% (90% PI 21.8%-62.4%) if uptake rates among MSM were doubled. The reductions in HPV16 infection prevalence were mostly achieved within 30 years of a targeted immunization campaign, during which they exceeded those induced by vaccinating 40% of preadolescent boys, if started simultaneously. The reduction in anal HPV16 prevalence amounted to 74.8% (90% PI 59.8%-93.0%) under a combined vaccination strategy. HPV16 prevalence reductions mostly exceeded vaccine coverage projections among MSM, illustrating the efficiency of prophylactic immunization even when the HPV vaccine is given after sexual debut. Mode of protection was identified as the key limitation to potential effectiveness of targeted vaccination, as the projected reductions were strongly reduced if we assumed no protection against future infections in recipients with prevalent infection or infection-derived immunity at the time of immunization. Unverified limitations of our study include the sparsity of data to inform the models, the omission of oral sex in transmission to the penile or anal site, and the restriction that our modeling results apply primarily to HIV-negative MSM. CONCLUSIONS Our findings suggest that targeted vaccination may generate considerable reductions in anogenital HPV16 infections among MSM, and has the potential to accelerate anal cancer prevention, especially when combined with sex-neutral vaccination in preadolescence.
Collapse
Affiliation(s)
- Johannes A. Bogaards
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
- Department of Epidemiology & Biostatistics, Amsterdam UMC, location VUmc, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
- * E-mail:
| | - Sofie H. Mooij
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
- Cluster of Infectious Diseases, Public Health Service of Amsterdam (GGD), Amsterdam, The Netherlands
| | - Maria Xiridou
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Maarten F. Schim van der Loeff
- Cluster of Infectious Diseases, Public Health Service of Amsterdam (GGD), Amsterdam, The Netherlands
- Amsterdam Infection & Immunity Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| |
Collapse
|
9
|
Qendri V, Bogaards JA, Berkhof J. Pricing of HPV vaccines in European tender-based settings. THE EUROPEAN JOURNAL OF HEALTH ECONOMICS : HEPAC : HEALTH ECONOMICS IN PREVENTION AND CARE 2019; 20:271-280. [PMID: 30051152 PMCID: PMC6439217 DOI: 10.1007/s10198-018-0996-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 07/18/2018] [Indexed: 05/07/2023]
Abstract
BACKGROUND Vaccine price is one of the most influential parameters in economic evaluations of HPV vaccination programmes. Vaccine tendering is a cost-containment method widely used by national or regional health authorities, but information on tender-based HPV vaccine prices is scarce. METHODS Procurement notices and awards for the HPV vaccines, published from January 2007 until January 2018, were systematically retrieved from the online platform for public procurement in Europe. Information was collected from national or regional tenders organized for publicly funded preadolescent vaccination programmes against HPV. The influence of variables on the vaccine price was estimated by means of a mixed-effects model. FINDINGS Prices were collected from 178 procurements announced in 15 European countries. The average price per dose for the first-generation HPV vaccines decreased from €101.8 (95% CI 91.3-114) in 2007 to €28.4 (22.6-33.5) in 2017, whereas the average dose price of the 9-valent vaccine in 2016-2017 was €49.1 (38.0-66.8). Unit prices were, respectively, €7.5 (4.4-10.6) and €34.4 (27.4-41.4) higher for the 4-valent and 9-valent vaccines than for the 2-valent vaccine. Contract volume and duration, level of procurement (region or country), per capita GDP and number of offers received had a significant effect on vaccine price. INTERPRETATION HPV vaccine procurement is widely used across Europe. The fourfold decrease in the average tender-based prices compared to list prices confirms the potential of tendering as an efficient cost-containment strategy, thereby expanding the indications for cost-effective HPV vaccination to previously ineligible target groups.
Collapse
Affiliation(s)
- Venetia Qendri
- Department of Epidemiology and Biostatistics, VU University Medical Center, PO Box 7057, MF F-wing ST, 1007 MB, Amsterdam, The Netherlands.
| | - Johannes A Bogaards
- Department of Epidemiology and Biostatistics, VU University Medical Center, PO Box 7057, MF F-wing ST, 1007 MB, Amsterdam, The Netherlands
- National Institute for Public Health and the Environment, Bilthoven, The Netherlands
| | - Johannes Berkhof
- Department of Epidemiology and Biostatistics, VU University Medical Center, PO Box 7057, MF F-wing ST, 1007 MB, Amsterdam, The Netherlands
| |
Collapse
|
10
|
Qendri V, Bogaards JA, Berkhof J. Who Will Benefit From Expanding HPV Vaccination Programs to Boys? JNCI Cancer Spectr 2018; 2:pky076. [PMID: 31360888 PMCID: PMC6649811 DOI: 10.1093/jncics/pky076] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 11/07/2018] [Accepted: 11/20/2018] [Indexed: 01/05/2023] Open
Abstract
Indications for human papillomavirus vaccination programs are expanding to boys. However, the rationale behind their inclusion is often not clear. Using a Bayesian synthesis framework and assuming equal vaccine coverage in both sexes, we assessed how the incremental number of cancer cases prevented and life-years gained from boys’ vaccination are distributed between women, heterosexual men, and men who have sex with men (MSM). Below 60% coverage, at least 50% of the gains from boys’ vaccination was attributable to cervical cancer prevention, whereas at 80% coverage, 50% of the gains was attributable to women, 15% to heterosexual men, and 35% to MSM. Above 90% coverage, 85–100% of the gains from boys’ vaccination was attributable to anal and oropharyngeal cancer prevention, mainly in MSM. Sex-neutral vaccination can be advocated on grounds of bolstering herd protection to women and directly protecting men, particularly MSM, with the clinical significance of either argument determined by the coverage.
Collapse
Affiliation(s)
- Venetia Qendri
- Correspondence to: Venetia Qendri, MSc, Department of Epidemiology and Biostatistics, Amsterdam UMC, Vrije Universiteit Amsterdam, PO Box 7057 MF F-wing ST, 1007 MB Amsterdam, the Netherlands (e-mail: )
| | | | | |
Collapse
|
11
|
Qendri V, Schurink-Van 't Klooster TM, Bogaards JA, Berkhof J. Ten years of HPV vaccination in the Netherlands: current evidence and future challenges in HPV-related disease prevention. Expert Rev Vaccines 2018; 17:1093-1104. [PMID: 30417704 DOI: 10.1080/14760584.2018.1547196] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
INTRODUCTION Girls-only vaccination against human papillomavirus (HPV) type 16 and 18 was implemented in the Netherlands in 2009. Despite the evidence of the efficacy against precancerous lesions, cross-protection induced by the vaccine and a greater potential for cancer prevention than cervical cancer only, vaccine coverage in the girls-only program has remained below target levels. AREAS COVERED In this paper, we review the literature from the Netherlands on the effectiveness and cost-effectiveness of HPV vaccination since vaccine introduction, give an account of the coverage, safety and effectiveness of HPV vaccination as has been reported in the Dutch surveillance program and discuss challenges of the current HPV vaccination program. EXPERT COMMENTARY Girls-only HPV vaccination may confer a substantial health gain in HPV-related disease prevention. However, vaccine coverage declined remarkably recently possibly related to safety concerns, limiting the benefits from girls' vaccination and increasing the potential additional benefit of sex-neutral HPV vaccination. Considering the emergence of novel vaccination and screening options and the change from cytology- to HPV-based screening in 2017, further research is required to inform decisions on the optimization of an integrated vaccination and screening program.
Collapse
Affiliation(s)
- V Qendri
- a Department of Epidemiology and Biostatistics , Amsterdam UMC, Vrije Universiteit Amsterdam , Amsterdam , Netherlands
| | - T M Schurink-Van 't Klooster
- b Center for Infectious Disease Control , National Institute for Public Health and the Environment , Bilthoven , Netherlands
| | - J A Bogaards
- a Department of Epidemiology and Biostatistics , Amsterdam UMC, Vrije Universiteit Amsterdam , Amsterdam , Netherlands.,b Center for Infectious Disease Control , National Institute for Public Health and the Environment , Bilthoven , Netherlands
| | - J Berkhof
- a Department of Epidemiology and Biostatistics , Amsterdam UMC, Vrije Universiteit Amsterdam , Amsterdam , Netherlands
| |
Collapse
|
12
|
Wolff E, Elfström KM, Haugen Cange H, Larsson S, Englund H, Sparén P, Roth A. Cost-effectiveness of sex-neutral HPV-vaccination in Sweden, accounting for herd-immunity and sexual behaviour. Vaccine 2018; 36:5160-5165. [PMID: 30017146 DOI: 10.1016/j.vaccine.2018.07.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 07/06/2018] [Accepted: 07/10/2018] [Indexed: 01/01/2023]
Abstract
INTRODUCTION The aim was to assess cost-effectiveness of expanding the Swedish HPV-vaccination program to include preadolescent boys, by comparing health-effects and costs of HPV-related disease, with a sex-neutral vaccination program versus only vaccinating girls. METHODS We used a dynamic compartmental model to simulate the burden of HPV16/18-related disease in Sweden, accounting for indirect effects of vaccination through herd-immunity. The model accounted for sexual behaviour, such as age preferences and men who have sex with men. The main outcome was number of individuals with HPV-related cancers (cervical, genital, anal and oropharyngeal cancer) and cervical intraepithelial neoplasia (CIN). Costs included in the analysis were those incurred when treating HPV-related cancer and CIN, production losses during sick-leave, and acquisition and administration of vaccine. Health effects were measured as quality-adjusted life years (QALY). The time horizon was set to 100 years, and both effects and costs were discounted by 3% annually. Health effects and costs were accumulated over the time horizon and used to create an incremental cost-effectiveness ratio. RESULTS A sex-neutral vaccination program would reduce HPV-related cancer and CIN, both due to direct effects among vaccinated as well as through herd-immunity, further decreasing HPV-related cancer burden annually by around 60 cases among men and women respectively in steady-state. The cost per gained QALY was estimated to 40,000 euro. Applying the procurement price of 2017, sex-neutral vaccination was dominant. CONCLUSION Introducing a sex-neutral HPV-vaccination program would be good value for money also in Sweden where there this 80% coverage in the current HPV-vaccination program for preadolescent girls. The cost-effectiveness of a sex-neutral program is highly dependent on the price of the vaccine, the lower the price the more favourable it is to also vaccinate boys.
Collapse
Affiliation(s)
- Ellen Wolff
- Public Health Agency of Sweden, Nobels väg 18, 171 82 Solna, Sweden; Gothenburg University, Institute of Medicine, Medicinaregatan 3, 405 30 Gothenburg, Sweden.
| | - K Miriam Elfström
- Karolinska Institutet, Stockholm Nobels väg 6, 171 77 Stockholm, Sweden; Regional Cancer Centre of Stockholm-Gotland, Västgötagatan 2, Sweden
| | - Hedda Haugen Cange
- Institute of Clinical Sciences, Sahlgrenska University Hospital, Dept. of Obstetrics and Gynecology, Sahlgrenska University Hospital, Östra, SE 416 85 Gothenburg, Sweden
| | - Sofie Larsson
- Public Health Agency of Sweden, Nobels väg 18, 171 82 Solna, Sweden; Gothenburg University, Institute of Medicine, Medicinaregatan 3, 405 30 Gothenburg, Sweden
| | - Helene Englund
- Public Health Agency of Sweden, Nobels väg 18, 171 82 Solna, Sweden
| | - Pär Sparén
- Karolinska Institutet, Stockholm Nobels väg 6, 171 77 Stockholm, Sweden
| | - Adam Roth
- Public Health Agency of Sweden, Nobels väg 18, 171 82 Solna, Sweden; Institution for Translational Medicine, Lund University, J Waldenströms g 35, CRC, hus 92, plan 11, Malmö, Sweden
| |
Collapse
|
13
|
Development of a human papillomavirus type 6/11 vaccine candidate for the prevention of condyloma acuminatum. Vaccine 2018; 36:4927-4934. [PMID: 30037483 DOI: 10.1016/j.vaccine.2018.06.041] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 05/23/2018] [Accepted: 06/16/2018] [Indexed: 11/23/2022]
Abstract
Condyloma acuminatum (CA) represents a significant human papillomavirus (HPV) disease burden worldwide, resulting in substantial healthcare costs and loss of life quality in both genders. To address this problem, we tried to develop a bivalent HPV6/11 virus-like particle (VLP) vaccine targeting CA. HPV6/11 VLPs were generated in Hansenula polymorpha, and a disassembly and reassembly (D/R) treatment was further conducted to improve the stability and monodispersity of the VLPs. The HPV6/11 VLPs were identified by transmission electron microscopy (TEM), high performance liquid chromatography (HPLC), mass spectrum (MS) and dynamic light scattering (DLS), and were evaluated for their immunogenicity in both mice and cynomolgus monkeys. The results showed that the HPV6/11 L1 proteins were correctly expressed and assembled into HPV6/11 VLPs, and the HPV6/11 VLPs formulated with aluminum phosphate induced vigorous production of specific neutralizing antibodies against HPV6/11 VLPs in mice and cynomolgus monkeys. These data indicated that the Hansenula polymorpha-derived HPV6/11 VLPs could be formulated into a bivalent vaccine used in prevention of CA.
Collapse
|
14
|
Riesen M, Garcia V, Low N, Althaus CL. Modeling the consequences of regional heterogeneity in human papillomavirus (HPV) vaccination uptake on transmission in Switzerland. Vaccine 2017; 35:7312-7321. [PMID: 29126806 DOI: 10.1016/j.vaccine.2017.10.103] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 10/24/2017] [Accepted: 10/31/2017] [Indexed: 01/15/2023]
Abstract
BACKGROUND Completed human papillomavirus (HPV) vaccination by age 16 years among women in Switzerland ranges from 17 to 75% across 26 cantons. The consequences of regional heterogeneity in vaccination coverage on transmission and prevalence of HPV-16 are unclear. METHODS We developed a deterministic, population-based model that describes HPV-16 transmission among young adults within and between the 26 cantons of Switzerland. We parameterized the model using sexual behavior data from Switzerland and data from the Swiss National Vaccination Coverage Survey. First, we investigated the general consequences of heterogeneity in vaccination uptake between two sub-populations. We then compared the predicted prevalence of HPV-16 resulting from heterogeneous HPV vaccination uptake in all of Switzerland with homogeneous vaccination at an uptake that is identical to the national average (52%). RESULTS In our baseline scenario, HPV-16 prevalence in women is 3.34% when vaccination is introduced and begins to diverge across cantons, ranging from 0.19 to 1.20% after 15 years of vaccination. After the same time period, overall prevalence of HPV-16 in Switzerland is only marginally higher (0.63%) with heterogeneous vaccination uptake than with homogeneous uptake (0.59%). Assuming inter-cantonal sexual mixing, cantons with low vaccination uptake benefit from a reduction in prevalence at the expense of cantons with high vaccination uptake. CONCLUSIONS Regional variations in uptake diminish the overall effect of vaccination on HPV-16 prevalence in Switzerland, but the effect size is small. Cantonal efforts towards HPV-prevalence reduction by increasing vaccination uptake are impaired by cantons with low vaccination uptake. Although the expected impact on national prevalence would be relatively small, harmonization of cantonal vaccination programs would reduce inter-cantonal differences in HPV-16 prevalence.
Collapse
Affiliation(s)
- Maurane Riesen
- Institute of Social and Preventive Medicine, University of Bern, Bern, Switzerland; Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland.
| | - Victor Garcia
- Institute of Social and Preventive Medicine, University of Bern, Bern, Switzerland.
| | - Nicola Low
- Institute of Social and Preventive Medicine, University of Bern, Bern, Switzerland.
| | - Christian L Althaus
- Institute of Social and Preventive Medicine, University of Bern, Bern, Switzerland.
| |
Collapse
|
15
|
Qendri V, Bogaards JA, Berkhof J. Health and Economic Impact of a Tender-Based, Sex-Neutral Human Papillomavirus 16/18 Vaccination Program in the Netherlands. J Infect Dis 2017; 216:210-219. [PMID: 28586466 DOI: 10.1093/infdis/jix272] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 06/02/2017] [Indexed: 12/27/2022] Open
Abstract
Background Uptake of human papillomavirus (HPV) vaccine among girls in the Dutch immunization program has plateaued at around 60%. Vaccinating boys may be an appealing complementary strategy for the prevention of HPV-related diseases, especially since tender negotiations and reduced dosing schemes have driven down the cost of vaccination. Methods We expanded a previously published Bayesian synthesis framework to account for all vaccine type-related cancers and herd immunity effects from vaccinating girls and boys. We evaluated the efficiency of vaccinating boys relative to increasing vaccine uptake among girls and assessed the cost-effectiveness of a sex-neutral program. Results Vaccinating 40% of boys along with 60% of girls yielded the same gain in life-years (LYs) as increasing the uptake in girls from 60% to 80%. The incremental cost-effectiveness ratio (ICER) of vaccinating boys was €9134/LY (95% credible interval [CrI], €7323/LY-€11231/LY) under 3% discounting. The ceiling vaccination costs at which the ICER remained below the per capita gross domestic product threshold was €240 (95% CrI, €200-€280) per vaccinated boy. If girls' uptake increased to 90%, the ceiling costs decreased to €70 (95% CrI, €40-€100) per vaccinated boy. Conclusions Vaccinating boys along with girls is only modestly less efficient than increasing uptake among girls and highly likely to be cost-effective under current vaccine costs and uptake in the Netherlands.
Collapse
Affiliation(s)
- Venetia Qendri
- Department of Epidemiology and Biostatistics, VU University Medical Center, Amsterdam
| | - Johannes A Bogaards
- Department of Epidemiology and Biostatistics, VU University Medical Center, Amsterdam.,Center for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, the Netherlands
| | - Johannes Berkhof
- Department of Epidemiology and Biostatistics, VU University Medical Center, Amsterdam
| |
Collapse
|
16
|
Heijne JCM, van Liere GAFS, Hoebe CJPA, Bogaards JA, van Benthem BHB, Dukers-Muijrers NHTM. What explains anorectal chlamydia infection in women? Implications of a mathematical model for test and treatment strategies. Sex Transm Infect 2017; 93:270-275. [PMID: 27986968 PMCID: PMC5520248 DOI: 10.1136/sextrans-2016-052786] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 11/03/2016] [Accepted: 11/28/2016] [Indexed: 11/07/2022] Open
Abstract
OBJECTIVES Female anorectal Chlamydia trachomatis (chlamydia) infections are common irrespective of recent anal sex. We explored the role of anorectal infections in chlamydia transmission and estimated the impact of interventions aimed at improved detection and treatment of anorectal infections. METHODS We developed a pair compartmental model of heterosexuals aged 15-29 years attending STI clinics, in which women can be susceptible to or infected with chlamydia urogenitally and/or anorectally and men urogenitally. Transmission probabilities per vaginal and anal sex act, together with an autoinoculation probability, were estimated by fitting to anatomic site-specific prevalence data (14% urogenital; 11% anorectal prevalence). We investigated the 10-year reduction in female chlamydia prevalence of interventions (universal anorectal testing of female STI clinic attendees or doxycycline use for urogenital chlamydia) relative to continued current care (anorectal testing on indication and doxycycline for anorectal and azithromycin for urogenital chlamydia). RESULTS The transmission probability per anal sex act was 5.8% (IQR 3.0-8.3%), per vaginal sex act 2.0% (IQR 1.7-2.2%) and the daily autoinoculation probability was 0.7% (IQR 0.5-1.0%). More anorectal chlamydia infections were caused by autoinoculation than by recent anal sex. Universal anorectal testing reduced population prevalence modestly with 8.7% (IQR 7.6-9.7%), yet the reduction was double that of doxycycline use for urogenital infections (4.3% (IQR 3.5-5.3%)) relative to continued current care. CONCLUSIONS Autoinoculation between anatomic sites in women might play a role in sustaining high chlamydia prevalence. A shift to more anorectal testing of female STI clinic attendees may be considered for its (albeit modest) impact on reducing prevalence.
Collapse
Affiliation(s)
- Janneke C M Heijne
- Centre for Infectious Diseases Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Geneviève A F S van Liere
- Department of Sexual Health, Infectious Diseases and Environmental Health, South Limburg Public Health Service, Geleen, Netherlands
- Department of Medical Microbiology, Care and Public Health Research Institute (CAPHRI), Maastricht University Medical Center (MUMC+), Maastricht, Netherlands
| | - Christian J P A Hoebe
- Department of Sexual Health, Infectious Diseases and Environmental Health, South Limburg Public Health Service, Geleen, Netherlands
- Department of Medical Microbiology, Care and Public Health Research Institute (CAPHRI), Maastricht University Medical Center (MUMC+), Maastricht, Netherlands
| | - Johannes A Bogaards
- Centre for Infectious Diseases Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Birgit H B van Benthem
- Centre for Infectious Diseases Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Nicole H T M Dukers-Muijrers
- Department of Sexual Health, Infectious Diseases and Environmental Health, South Limburg Public Health Service, Geleen, Netherlands
- Department of Medical Microbiology, Care and Public Health Research Institute (CAPHRI), Maastricht University Medical Center (MUMC+), Maastricht, Netherlands
| |
Collapse
|
17
|
Ryser MD, Gravitt PE, Myers ER. Mechanistic mathematical models: An underused platform for HPV research. PAPILLOMAVIRUS RESEARCH 2017; 3:46-49. [PMID: 28720456 PMCID: PMC5518640 DOI: 10.1016/j.pvr.2017.01.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 01/20/2017] [Accepted: 01/31/2017] [Indexed: 01/19/2023]
Abstract
Health economic modeling has become an invaluable methodology for the design and evaluation of clinical and public health interventions against the human papillomavirus (HPV) and associated diseases. At the same time, relatively little attention has been paid to a different yet complementary class of models, namely that of mechanistic mathematical models. The primary focus of mechanistic mathematical models is to better understand the intricate biologic mechanisms and dynamics of disease. Inspired by a long and successful history of mechanistic modeling in other biomedical fields, we highlight several areas of HPV research where mechanistic models have the potential to advance the field. We argue that by building quantitative bridges between biologic mechanism and population level data, mechanistic mathematical models provide a unique platform to enable collaborations between experimentalists who collect data at different physical scales of the HPV infection process. Through such collaborations, mechanistic mathematical models can accelerate and enhance the investigation of HPV and related diseases.
Collapse
Affiliation(s)
- Marc D Ryser
- Department of Surgery, Division of Advanced Oncologic and GI Surgery, Duke University School of Medicine, Durham, NC, USA; Department of Mathematics, Duke University, Durham, NC, USA.
| | - Patti E Gravitt
- Department of Global Health, Milken Institute School of Public Health, George Washington University, Washington, DC, USA
| | - Evan R Myers
- Department of Obstetrics & Gynecology, Duke University School of Medicine, Durham, NC, USA
| |
Collapse
|
18
|
Brisson M, Bénard É, Drolet M, Bogaards JA, Baussano I, Vänskä S, Jit M, Boily MC, Smith MA, Berkhof J, Canfell K, Chesson HW, Burger EA, Choi YH, De Blasio BF, De Vlas SJ, Guzzetta G, Hontelez JAC, Horn J, Jepsen MR, Kim JJ, Lazzarato F, Matthijsse SM, Mikolajczyk R, Pavelyev A, Pillsbury M, Shafer LA, Tully SP, Turner HC, Usher C, Walsh C. Population-level impact, herd immunity, and elimination after human papillomavirus vaccination: a systematic review and meta-analysis of predictions from transmission-dynamic models. Lancet Public Health 2016; 1:e8-e17. [PMID: 29253379 PMCID: PMC6727207 DOI: 10.1016/s2468-2667(16)30001-9] [Citation(s) in RCA: 174] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 08/26/2016] [Accepted: 08/30/2016] [Indexed: 01/17/2023]
Abstract
BACKGROUND Modelling studies have been widely used to inform human papillomavirus (HPV) vaccination policy decisions; however, many models exist and it is not known whether they produce consistent predictions of population-level effectiveness and herd effects. We did a systematic review and meta-analysis of model predictions of the long-term population-level effectiveness of vaccination against HPV 16, 18, 6, and 11 infection in women and men, to examine the variability in predicted herd effects, incremental benefit of vaccinating boys, and potential for HPV-vaccine-type elimination. METHODS We searched MEDLINE and Embase for transmission-dynamic modelling studies published between Jan 1, 2009, and April 28, 2015, that predicted the population-level impact of vaccination on HPV 6, 11, 16, and 18 infections in high-income countries. We contacted authors to determine whether they were willing to produce new predictions for standardised scenarios. Strategies investigated were girls-only vaccination and girls and boys vaccination at age 12 years. Base-case vaccine characteristics were 100% efficacy and lifetime protection. We did sensitivity analyses by varying vaccination coverage, vaccine efficacy, and duration of protection. For all scenarios we pooled model predictions of relative reductions in HPV prevalence (RRprev) over time after vaccination and summarised results using the median and 10th and 90th percentiles (80% uncertainty intervals [UI]). FINDINGS 16 of 19 eligible models from ten high-income countries provided predictions. Under base-case assumptions, 40% vaccination coverage and girls-only vaccination, the RRprev of HPV 16 among women and men was 0·53 (80% UI 0·46-0·68) and 0·36 (0·28-0·61), respectively, after 70 years. With 80% girls-only vaccination coverage, the RRprev of HPV 16 among women and men was 0·93 (0·90-1·00) and 0·83 (0·75-1·00), respectively. Vaccinating boys in addition to girls increased the RRprev of HPV 16 among women and men by 0·18 (0·13-0·32) and 0·35 (0·27-0·39) for 40% coverage, and 0·07 (0·00-0·10) and 0·16 (0·01-0·25) for 80% coverage, respectively. The RRprev were greater for HPV 6, 11, and 18 than for HPV 16 for all scenarios investigated. Finally at 80% coverage, most models predicted that girls and boys vaccination would eliminate HPV 6, 11, 16, and 18, with a median RRprev of 1·00 for women and men for all four HPV types. Variability in pooled findings was low, but increased with lower vaccination coverage and shorter vaccine protection (from lifetime to 20 years). INTERPRETATION Although HPV models differ in structure, data used for calibration, and settings, our population-level predictions were generally concordant and suggest that strong herd effects are expected from vaccinating girls only, even with coverage as low as 20%. Elimination of HPV 16, 18, 6, and 11 is possible if 80% coverage in girls and boys is reached and if high vaccine efficacy is maintained over time. FUNDING Canadian Institutes of Health Research.
Collapse
Affiliation(s)
- Marc Brisson
- Centre de recherche du CHU de Québec-Université Laval, Quebec City, QC, Canada; Département de médecine sociale et préventive, Université Laval, Quebec City, QC, Canada; Department of Infectious Disease Epidemiology, Imperial College, London, UK.
| | - Élodie Bénard
- Centre de recherche du CHU de Québec-Université Laval, Quebec City, QC, Canada; Département de médecine sociale et préventive, Université Laval, Quebec City, QC, Canada
| | - Mélanie Drolet
- Centre de recherche du CHU de Québec-Université Laval, Quebec City, QC, Canada
| | - Johannes A Bogaards
- Centre for Infectious Disease Control, National Institute of Public Health and the Environment, Bilthoven, Netherlands
| | - Iacopo Baussano
- Infection and Cancer Epidemiology Group, International Agency for Research on Cancer, Lyon, France
| | - Simopekka Vänskä
- Vaccination Programme Unit, National Institute for Health and Welfare, Helsinki, Finland
| | - Mark Jit
- Modelling and Economics Unit, Public Health England, London, UK; Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Marie-Claude Boily
- Département de médecine sociale et préventive, Université Laval, Quebec City, QC, Canada; Department of Infectious Disease Epidemiology, Imperial College, London, UK
| | - Megan A Smith
- Cancer Research Division, Cancer Council NSW, Sydney, NSW, Australia
| | - Johannes Berkhof
- Department of Epidemiology and Biostatistics, VU University Medical Center, Amsterdam, Netherlands
| | - Karen Canfell
- Cancer Research Division, Cancer Council NSW, Sydney, NSW, Australia; Lowy Cancer Research Centre, Prince of Wales Clinical School, University of New South Wales, Sydney, NSW, Australia
| | - Harrell W Chesson
- Division of STD Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Emily A Burger
- Center for Health Decision Science, Harvard T H Chan School of Public Health, Boston, MA, USA; Department of Health Management and Health Economics, University of Oslo, Oslo, Norway
| | - Yoon H Choi
- National Infection Service, Public Health England, London, UK
| | - Birgitte Freiesleben De Blasio
- Oslo Centre for Biostatistics and Epidemiology, Division of Infectious Disease Control, Norwegian Institute of Public Health and Oslo Centre for Statistics and Epidemiology, Oslo, Norway; Department of Biostatistics, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Sake J De Vlas
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
| | | | - Jan A C Hontelez
- Department of Global Health and Population, Harvard T H Chan School of Public Health, Boston, MA, USA; Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Johannes Horn
- Epidemiological and Statistical Methods Research Group, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Martin R Jepsen
- Section for Geography, Department of Geosciences and Natural Resource Management, University of Copenhagen, Copenhagen, Denmark
| | - Jane J Kim
- Center for Health Decision Science, Harvard T H Chan School of Public Health, Boston, MA, USA
| | - Fulvio Lazzarato
- Infection and Cancer Epidemiology Group, International Agency for Research on Cancer, Lyon, France; Unit of Cancer Epidemiology, Department of Medical Sciences, University of Turin, Turin, Italy
| | - Suzette M Matthijsse
- Department of Public Health, Erasmus MC, University Medical Center Rotterdam, Rotterdam, Netherlands
| | - Rafael Mikolajczyk
- Epidemiological and Statistical Methods Research Group, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | | | | | - Leigh Anne Shafer
- Department of Internal Medicine, University of Manitoba, Winnipeg, MB, Canada
| | - Stephen P Tully
- Infection and Cancer Epidemiology Group, International Agency for Research on Cancer, Lyon, France
| | - Hugo C Turner
- Department of Infectious Disease Epidemiology, Imperial College, London, UK
| | - Cara Usher
- National Centre for Pharmacoeconomics (NCPE Ireland), Dublin, Ireland
| | - Cathal Walsh
- Department of Mathematics and Statistics, University of Limerick, Limerick, Ireland
| |
Collapse
|
19
|
Ben Hadj Yahia MB, Jouin-Bortolotti A, Dervaux B. Extending the Human Papillomavirus Vaccination Programme to Include Males in High-Income Countries: A Systematic Review of the Cost-Effectiveness Studies. Clin Drug Investig 2016; 35:471-85. [PMID: 26187455 DOI: 10.1007/s40261-015-0308-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND AND OBJECTIVES Giving the human papillomavirus (HPV) vaccination to females has been shown to be cost-effective in most countries. The epidemiological evidence and economic burden of HPV-related diseases have gradually been shown to be gender neutral. Randomized clinical trials report high efficacy, immunogenicity and safety of the HPV vaccine in males aged 16-26 years. Some pioneering countries extended their HPV vaccination programme to include males, regardless of the cost-effectiveness analysis results. Nevertheless, decision makers need evidence provided by modelling and economic studies to justify the funding of mass vaccination. This systematic review aims to assess the cost-effectiveness of extending the HPV vaccination programme to include males living in high-income countries. METHODS A systematic review of the cost-effectiveness analyses of HPV vaccination in males was performed. Data were extracted and analysed using a checklist adapted from the Consolidated Health Economic Evaluation Reporting Standards Statement. RESULTS Seventeen studies and 12 underlying mathematical models were identified. Model filiation showed evolution in time from aggregate models (static and dynamic) to individual-based models. When considering the health outcomes HPV vaccines are licensed for, regardless of modelling approaches and assumptions, extending vaccinations to males is rarely found to be cost-effective in heterosexual populations. Cost-effectiveness ratios become more attractive when all HPV-related diseases are considered and when vaccine coverage in females is below 40%. CONCLUSION Targeted vaccination of men who have sex with men (MSM) seems to be the best cost-effectiveness option. The feasibility of this strategy is still an open question, since early identification of this specific population remains difficult.
Collapse
Affiliation(s)
- Mohamed-Béchir Ben Hadj Yahia
- Department of Epidemiology, Health Economics and Prevention, Lille University Hospital, CHRU de Lille, Pôle S3P, Maison Régionale de la Recherche Clinique, 6, rue du Pr Laguesse, CS 70001, 59037, Lille Cedex, France,
| | | | | |
Collapse
|
20
|
Genital Chlamydia trachomatis: understanding the roles of innate and adaptive immunity in vaccine research. Clin Microbiol Rev 2016; 27:346-70. [PMID: 24696438 DOI: 10.1128/cmr.00105-13] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Chlamydia trachomatis is the leading cause of bacterial sexually transmitted disease worldwide, and despite significant advances in chlamydial research, a prophylactic vaccine has yet to be developed. This Gram-negative obligate intracellular bacterium, which often causes asymptomatic infection, may cause pelvic inflammatory disease (PID), ectopic pregnancies, scarring of the fallopian tubes, miscarriage, and infertility when left untreated. In the genital tract, Chlamydia trachomatis infects primarily epithelial cells and requires Th1 immunity for optimal clearance. This review first focuses on the immune cells important in a chlamydial infection. Second, we summarize the research and challenges associated with developing a chlamydial vaccine that elicits a protective Th1-mediated immune response without inducing adverse immunopathologies.
Collapse
|
21
|
Handler NS, Handler MZ, Majewski S, Schwartz RA. Human papillomavirus vaccine trials and tribulations: Vaccine efficacy. J Am Acad Dermatol 2016; 73:759-67; quiz 767-8. [PMID: 26475535 DOI: 10.1016/j.jaad.2015.05.041] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 04/27/2015] [Accepted: 05/14/2015] [Indexed: 11/19/2022]
Abstract
As of December 2014, there were 3 approved vaccines for human papillomavirus (HPV): bivalent Cervarix (GlaxoSmithKline, New York, NY), quadrivalent Gardasil (Merck and Co, Kenilworth, NJ), and 9-valent Gardasil-9 (Merck and Co). The average cost per dose is $120, with a recommended 3-dose course. The quadrivalent vaccine is the most widely administered worldwide. As with the bivalent and 9-valent vaccines, the vaccine is considered safe, although concerns have been raised. In addition to immunization against the targeted HPV types, there is evidence that there is cross protection against other types of HPV. This continuing medical education review evaluates the differences in vaccines that are currently on the market; part II focuses on the cost-effectiveness of vaccination, the HPV vaccination programs currently instituted around the globe, efficacy, and safety.
Collapse
Affiliation(s)
- Nancy S Handler
- Dermatology, Rutgers University New Jersey Medical School, Newark, New Jersey; University of Nebraska Medical Center, College of Medicine, Omaha, Nebraska
| | - Marc Z Handler
- Dermatology, Rutgers University New Jersey Medical School, Newark, New Jersey
| | - Slawomir Majewski
- Department of Dermatology and Venereology, Medical University of Warsaw, Warsaw, Poland
| | - Robert A Schwartz
- Dermatology, Rutgers University New Jersey Medical School, Newark, New Jersey; Pathology, Rutgers University New Jersey Medical School, Newark, New Jersey; Pediatrics, Rutgers University New Jersey Medical School, Newark, New Jersey; Medicine, Rutgers University New Jersey Medical School, Newark, New Jersey; Preventive Medicine and Community Health, Rutgers University New Jersey Medical School, Newark, New Jersey.
| |
Collapse
|
22
|
Elfström KM, Lazzarato F, Franceschi S, Dillner J, Baussano I. Human Papillomavirus Vaccination of Boys and Extended Catch-up Vaccination: Effects on the Resilience of Programs. J Infect Dis 2016; 213:199-205. [PMID: 26142436 DOI: 10.1093/infdis/jiv368] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 06/25/2015] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Decreasing human papillomavirus (HPV) vaccine prices makes scaling up of vaccination programs attractive for countries that initially targeted 1 or a few birth cohorts of girls and/or achieved low coverage. This article aims to compare the impact of alternative HPV vaccination strategies, using data from Sweden, a high-income country that has experienced vaccine price changes. METHODS Using an HPV transmission model, we compared the existing vaccination program to alternatives, accounting for a 1-time catch-up vaccination of 22-26-year-old women, with or without routine vaccination of school-age boys, and for a 1-time catch-up vaccination of males aged 13-26 years. We also assessed the resilience of vaccination alternatives to coverage reduction. RESULTS On the basis of an HPV16/18 prevalence of 12% before the HPV vaccine era, extended catch-up vaccination for females and males yielded relative reductions in the HPV prevalence of 49.4% and 55.6%, respectively, during the first 10 years after the start of each vaccination strategy, whereas the existing program yielded a relative reduction of 38.6% during the same period. The increased prevalence reduction due to catch-up vaccination continued for about 30 years. As compared to female-only routine and extended catch-up vaccination, routine vaccination of males with or without catch-up was, respectively, 12.6-fold and 7.2-fold more resilient to coverage reduction. CONCLUSIONS Vaccination strategies based on catch-up vaccination of females and males are effective for accelerating HPV prevalence reduction. Inclusion of routine male vaccination improves the resilience of vaccination programs.
Collapse
Affiliation(s)
| | - Fulvio Lazzarato
- Department of Translational Medicine, University of Piemonte Orientale Avogadro, Novara Unit of Cancer Epidemiology, Department of Medical Sciences, University of Turin, Italy International Agency for Research on Cancer, Lyon, France
| | | | - Joakim Dillner
- Department of Medical Epidemiology and Biostatistics Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden
| | | |
Collapse
|
23
|
Takes RP, Wierzbicka M, D'Souza G, Jackowska J, Silver CE, Rodrigo JP, Dikkers FG, Olsen KD, Rinaldo A, Brakenhoff RH, Ferlito A. HPV vaccination to prevent oropharyngeal carcinoma: What can be learned from anogenital vaccination programs? Oral Oncol 2015; 51:1057-60. [PMID: 26520047 DOI: 10.1016/j.oraloncology.2015.10.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Revised: 09/22/2015] [Accepted: 10/13/2015] [Indexed: 12/26/2022]
Abstract
Human papillomavirus (HPV) infections are well known causes of anogenital cancers. Recent studies show that HPV also plays a role in oropharyngeal cancer (OPC). A review on the role of HPV vaccination in the prevention of head and neck squamous cell carcinoma (HNSCC) with special emphasis on OPC was conducted and available vaccines and vaccination strategies in HNSCC and OPC are discussed. Prophylactic vaccination is known to be effective for prevention of anogenital HPV infection and precursor lesions in the cervix and anus. While the value of vaccination for prevention of OPC and possibly as an adjuvant treatment is still an open question, evidence to date supports the possibility that HPV vaccination may prove to be effective in reducing the incidence of this malignancy.
Collapse
Affiliation(s)
- Robert P Takes
- Department of Otolaryngology - Head and Neck Surgery, Radboud University Medical Center, Nijmegen, The Netherlands.
| | - Małgorzata Wierzbicka
- Department of Otolaryngology - Head and Neck Surgery, Poznań University of Medical Sciences, Poznan, Poland
| | - Gypsyamber D'Souza
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA
| | - Joanna Jackowska
- Department of Otolaryngology - Head and Neck Surgery, Poznań University of Medical Sciences, Poznan, Poland
| | - Carl E Silver
- Departments of Surgery and Otolaryngology - Head and Neck Surgery, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Juan P Rodrigo
- Department of Otolaryngology, Hospital Universitario Central de Asturias, Oviedo, Spain; Instituto Universitario de Oncología del Principado de Asturias, Oviedo, Spain
| | - Frederik G Dikkers
- Department of Otorhinolaryngology - Head and Neck Surgery, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Kerry D Olsen
- Department of Otolaryngology - Head and Neck Surgery, Mayo Clinic, Rochester, MN, USA
| | | | - Ruud H Brakenhoff
- Department of Otolaryngology - Head and Neck Surgery, VU University Medical Center, Amsterdam, The Netherlands
| | - Alfio Ferlito
- Coordinator of the International Head and Neck Scientific Group, Padua, Italy
| |
Collapse
|
24
|
The estimated impact of natural immunity on the effectiveness of human papillomavirus vaccination. Vaccine 2015; 33:5357-5364. [DOI: 10.1016/j.vaccine.2015.08.079] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 08/21/2015] [Accepted: 08/28/2015] [Indexed: 11/19/2022]
|
25
|
Bogaards JA, Wallinga J, Brakenhoff RH, Meijer CJLM, Berkhof J. Direct benefit of vaccinating boys along with girls against oncogenic human papillomavirus: bayesian evidence synthesis. BMJ 2015; 350:h2016. [PMID: 25985328 PMCID: PMC4428278 DOI: 10.1136/bmj.h2016] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/16/2015] [Indexed: 12/12/2022]
Abstract
OBJECTIVE To assess the reduction in the vaccine preventable burden of cancer in men if boys are vaccinated along with girls against oncogenic human papillomavirus (HPV). DESIGN Bayesian evidence synthesis approach used to evaluate the impact of vaccination against HPV types 16 and 18 on the burden of anal, penile, and oropharyngeal carcinomas among heterosexual men and men who have sex with men. The reduced transmission of vaccine-type HPV from vaccination of girls was assumed to lower the risk of HPV associated cancer in all men but not to affect the excess risk of HPV associated cancers among men who have sex with men. SETTING General population in the Netherlands. INTERVENTION Inclusion of boys aged 12 into HPV vaccination programmes. MAIN OUTCOME MEASURES Quality adjusted life years (QALYs) and numbers needed to vaccinate. RESULTS Before HPV vaccination, 14.9 (95% credible interval 12.2 to 18.1) QALYs per thousand men were lost to vaccine preventable cancers associated with HPV in the Netherlands. This burden would be reduced by 37% (28% to 48%) if the vaccine uptake among girls remains at the current level of 60%. To prevent one additional case of cancer among men, 795 boys (660 to 987) would need to be vaccinated; with tumour specific numbers for anal, penile, and oropharyngeal cancer of 2162, 3486, and 1975, respectively. The burden of HPV related cancer in men would be reduced by 66% (53% to 805) if vaccine uptake among girls increases to 90%. In that case, 1735 boys (1240 to 2900) would need to be vaccinated to prevent an additional case; with tumour specific numbers for anal, penile, and oropharyngeal cancer of 2593, 29107, and 6484, respectively. CONCLUSIONS Men will benefit indirectly from vaccination of girls but remain at risk of cancers associated with HPV. The incremental benefit of vaccinating boys when vaccine uptake among girls is high is driven by the prevention of anal carcinomas, which underscores the relevance of HPV prevention efforts for men who have sex with men.
Collapse
Affiliation(s)
- Johannes A Bogaards
- Department of Epidemiology and Biostatistics, VU University Medical Centre, PO Box 7057, 1007 MB Amsterdam, Netherlands Centre for Infectious Disease Control, National Institute for Public Health and the Environment, PO Box 1, 3720 BA Bilthoven, Netherlands
| | - Jacco Wallinga
- Centre for Infectious Disease Control, National Institute for Public Health and the Environment, PO Box 1, 3720 BA Bilthoven, Netherlands
| | - Ruud H Brakenhoff
- Department of Otolaryngology/Head and Neck Surgery, VU University Medical Centre, PO Box 7057, 1007 MB Amsterdam, Netherlands
| | - Chris J L M Meijer
- Department of Pathology, VU University Medical Centre, PO Box 7057, 1007 MB Amsterdam, Netherlands
| | - Johannes Berkhof
- Department of Epidemiology and Biostatistics, VU University Medical Centre, PO Box 7057, 1007 MB Amsterdam, Netherlands
| |
Collapse
|
26
|
Drolet M, Bénard É, Boily MC, Ali H, Baandrup L, Bauer H, Beddows S, Brisson J, Brotherton JML, Cummings T, Donovan B, Fairley CK, Flagg EW, Johnson AM, Kahn JA, Kavanagh K, Kjaer SK, Kliewer EV, Lemieux-Mellouki P, Markowitz L, Mboup A, Mesher D, Niccolai L, Oliphant J, Pollock KG, Soldan K, Sonnenberg P, Tabrizi SN, Tanton C, Brisson M. Population-level impact and herd effects following human papillomavirus vaccination programmes: a systematic review and meta-analysis. THE LANCET. INFECTIOUS DISEASES 2015; 15:565-80. [PMID: 25744474 PMCID: PMC5144106 DOI: 10.1016/s1473-3099(14)71073-4] [Citation(s) in RCA: 457] [Impact Index Per Article: 50.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND Human papillomavirus (HPV) vaccination programmes were first implemented in several countries worldwide in 2007. We did a systematic review and meta-analysis to assess the population-level consequences and herd effects after female HPV vaccination programmes, to verify whether or not the high efficacy reported in randomised controlled clinical trials are materialising in real-world situations. METHODS We searched the Medline and Embase databases (between Jan 1, 2007 and Feb 28, 2014) and conference abstracts for time-trend studies that analysed changes, between the pre-vaccination and post-vaccination periods, in the incidence or prevalence of at least one HPV-related endpoint: HPV infection, anogenital warts, and high-grade cervical lesions. We used random-effects models to derive pooled relative risk (RR) estimates. We stratified all analyses by age and sex. We did subgroup analyses by comparing studies according to vaccine type, vaccination coverage, and years since implementation of the vaccination programme. We assessed heterogeneity across studies using I(2) and χ(2) statistics and we did trends analysis to examine the dose-response association between HPV vaccination coverage and each study effect measure. FINDINGS We identified 20 eligible studies, which were all undertaken in nine high-income countries and represent more than 140 million person-years of follow-up. In countries with female vaccination coverage of at least 50%, HPV type 16 and 18 infections decreased significantly between the pre-vaccination and post-vaccination periods by 68% (RR 0·32, 95% CI 0·19-0·52) and anogenital warts decreased significantly by 61% (0·39, 0·22-0·71) in girls 13-19 years of age. Significant reductions were also recorded in HPV types 31, 33, and 45 in this age group of girls (RR 0·72, 95% CI 0·54-0·96), which suggests cross-protection. Additionally, significant reductions in anogenital warts were also reported in boys younger than 20 years of age (0·66 [95% CI 0·47-0·91]) and in women 20-39 years of age (0·68 [95% CI 0·51-0·89]), which suggests herd effects. In countries with female vaccination coverage lower than 50%, significant reductions in HPV types 16 and 18 infection (RR 0·50, 95% CI 0·34-0·74]) and in anogenital warts (0·86 [95% CI 0·79-0·94]) occurred in girls younger than 20 years of age, with no indication of cross-protection or herd effects. INTERPRETATION Our results are promising for the long-term population-level effects of HPV vaccination programmes. However, continued monitoring is essential to identify any signals of potential waning efficacy or type-replacement. FUNDING The Canadian Institutes of Health Research.
Collapse
Affiliation(s)
- Mélanie Drolet
- Centre de Recherche du CHU de Québec, Québec, QC, Canada; Département de Médecine Sociale et Préventive, Université Laval, Québec, QC, Canada
| | - Élodie Bénard
- Centre de Recherche du CHU de Québec, Québec, QC, Canada; Département de Médecine Sociale et Préventive, Université Laval, Québec, QC, Canada
| | - Marie-Claude Boily
- Centre de Recherche du CHU de Québec, Québec, QC, Canada; Département de Médecine Sociale et Préventive, Université Laval, Québec, QC, Canada; Department of Infectious Disease Epidemiology, Imperial College London, London, UK
| | - Hammad Ali
- The Kirby Institute, University of New South Wales, Sydney, NSW, Australia
| | - Louise Baandrup
- Unit of Virus, Lifestyle and Genes, The Danish Cancer Society Research Centre, Copenhagen, Denmark
| | - Heidi Bauer
- STD Control Branch of the California Department of Public Health, Richmond, CA, USA
| | - Simon Beddows
- Virus Reference Department, Public Health England, London, UK
| | - Jacques Brisson
- Centre de Recherche du CHU de Québec, Québec, QC, Canada; Département de Médecine Sociale et Préventive, Université Laval, Québec, QC, Canada
| | - Julia M L Brotherton
- National HPV Vaccination Program Register, Victorian Cytology Service, East Melbourne, Melbourne, VIC, Australia; Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, VIC, Australia
| | - Teresa Cummings
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Basil Donovan
- The Kirby Institute, University of New South Wales, Sydney, NSW, Australia
| | - Christopher K Fairley
- Melbourne Sexual Health Centre, Melbourne, VIC, Australia; Central Clinical School, Monash University, Alfred Hospital, Melbourne, VIC, Australia
| | - Elaine W Flagg
- National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP), Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Anne M Johnson
- Research Department of Infection and Population Health, University College London, London, UK
| | - Jessica A Kahn
- Cincinnati Children's Hospital Medical Center and the University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Kimberley Kavanagh
- Department of Mathematics and Statistics, University of Strathclyde, Glasgow, UK
| | - Susanne K Kjaer
- Unit of Virus, Lifestyle and Genes, The Danish Cancer Society Research Centre, Copenhagen, Denmark; Department of Gynecology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Erich V Kliewer
- Community Health Sciences, University of Manitoba, Winnipeg, MB, Canada; Cancer Control Research, British Columbia Cancer Agency, Vancouver, BC, Canada; Epidemiology and Cancer Registry, CancerCare Manitoba, Winnipeg, MB, Canada
| | - Philippe Lemieux-Mellouki
- Centre de Recherche du CHU de Québec, Québec, QC, Canada; Département de Médecine Sociale et Préventive, Université Laval, Québec, QC, Canada
| | - Lauri Markowitz
- National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP), Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Aminata Mboup
- Centre de Recherche du CHU de Québec, Québec, QC, Canada
| | - David Mesher
- HIV and STI Department, Centre for Infectious Disease Surveillance and Control, Public Health England, London, UK
| | - Linda Niccolai
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, Yale University, CT, USA
| | | | | | - Kate Soldan
- HIV and STI Department, Centre for Infectious Disease Surveillance and Control, Public Health England, London, UK
| | - Pam Sonnenberg
- Research Department of Infection and Population Health, University College London, London, UK
| | - Sepehr N Tabrizi
- Department of Obstetrics and Gynaecology, The University of Melbourne, Melbourne, VIC, Australia; Regional WHO HPV Reference Laboratory, Department of Microbiology and Infectious Diseases, The Royal Women's Hospital, Parkville, VIC, Australia; Murdoch Childrens Research Institute, Parkville, VIC, Australia
| | - Clare Tanton
- Research Department of Infection and Population Health, University College London, London, UK
| | - Marc Brisson
- Centre de Recherche du CHU de Québec, Québec, QC, Canada; Département de Médecine Sociale et Préventive, Université Laval, Québec, QC, Canada; Department of Infectious Disease Epidemiology, Imperial College London, London, UK.
| |
Collapse
|
27
|
Kumar S, Biswas M, Jose T. HPV vaccine: Current status and future directions. Med J Armed Forces India 2015; 71:171-7. [PMID: 25859081 PMCID: PMC4388981 DOI: 10.1016/j.mjafi.2015.02.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2015] [Accepted: 02/19/2015] [Indexed: 02/08/2023] Open
Abstract
HPV Vaccine was introduced to prevent cervical cancer known to be caused by infection with one or more of the high risk subtypes of the Human papilloma virus (HPV). Since introduction, trials have proven its efficacy in preventing Cervical intraepithelial neoplasia (CIN) beyond doubt and its effectiveness in preventing cervical cancer though presumptive is reasonably certain as per mathematical modelling. It also prevents other HPV related anogenital and oropharyngeal malignancies in both sexes. HPV vaccines have courted many controversies related to its efficacy, safety, ideal age of vaccination, use in HPV infected individuals and use in males. The currently available vaccines are based on L1 Viral like particles (VLP) and hence highly species specific, thermolabile, costly and are purely prophylactic. The quest for a cheaper, thermostable and broad spectrum vaccine has led to many newer prophylactic vaccines. Therapeutic vaccines were born out of the inescapable necessity considering high HPV related morbidity projected in the non HPV naïve population. Therapeutic vaccines would immediately reduce this burden and also help in the management of HPV related cancers alone or as part of combination strategies. Ongoing research is aimed at a total control over HPV related malignancies in the near future.
Collapse
Affiliation(s)
- Sushil Kumar
- Director and Commandant, Armed Forces Medical College, Pune 411040, India
| | - Manash Biswas
- Professor and Head, Department of Obstetrics and Gynaecology, Armed Forces Medical College, Pune 411040, India
| | - Tony Jose
- Associate Professor, Department of Obstetrics and Gynaecology, Armed Forces Medical College, Pune 411040, India
| |
Collapse
|
28
|
Ryser MD, McGoff K, Herzog DP, Sivakoff DJ, Myers ER. Impact of coverage-dependent marginal costs on optimal HPV vaccination strategies. Epidemics 2015; 11:32-47. [PMID: 25979280 DOI: 10.1016/j.epidem.2015.01.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Revised: 01/26/2015] [Accepted: 01/27/2015] [Indexed: 12/22/2022] Open
Abstract
The effectiveness of vaccinating males against the human papillomavirus (HPV) remains a controversial subject. Many existing studies conclude that increasing female coverage is more effective than diverting resources into male vaccination. Recently, several empirical studies on HPV immunization have been published, providing evidence of the fact that marginal vaccination costs increase with coverage. In this study, we use a stochastic agent-based modeling framework to revisit the male vaccination debate in light of these new findings. Within this framework, we assess the impact of coverage-dependent marginal costs of vaccine distribution on optimal immunization strategies against HPV. Focusing on the two scenarios of ongoing and new vaccination programs, we analyze different resource allocation policies and their effects on overall disease burden. Our results suggest that if the costs associated with vaccinating males are relatively close to those associated with vaccinating females, then coverage-dependent, increasing marginal costs may favor vaccination strategies that entail immunization of both genders. In particular, this study emphasizes the necessity for further empirical research on the nature of coverage-dependent vaccination costs.
Collapse
Affiliation(s)
- Marc D Ryser
- Department of Mathematics, Duke University, Durham, NC 27708, USA.
| | - Kevin McGoff
- Department of Mathematics, Duke University, Durham, NC 27708, USA
| | - David P Herzog
- Department of Mathematics, Drake University, Des Moines, IA 50311, USA
| | - David J Sivakoff
- Department of Statistics, The Ohio State University, Columbus, OH 43210, USA; Department of Mathematics, The Ohio State University, Columbus, OH 43210, USA
| | - Evan R Myers
- Department of Obstetrics and Gynecology, Duke University Medical School, Durham, NC 27708, USA
| |
Collapse
|
29
|
Abstract
Human papillomaviruses (HPV) are the causative agents of cervical cancer, the third most common cancer in women. The development of prophylactic HPV vaccines Gardasil® and Cervarix® targeting the major oncogenic HPV types is now the frontline of cervical cancer prevention. Both vaccines have been proven to be highly effective and safe although there are still open questions about their target population, cross-protection, and long-term efficacy. The main limitation for a worldwide implementation of Gardasil® and Cervarix® is their high cost. To develop more affordable vaccines research groups are concentrated in new formulations with different antigens including capsomeres, the minor capsid protein L2 and DNA. In this article we describe the vaccines' impact on HPV-associated disease, the main open questions about the marketed vaccines, and current efforts for the development of second-generation vaccines.
Collapse
|
30
|
Smith MA, Canfell K. Incremental benefits of male HPV vaccination: accounting for inequality in population uptake. PLoS One 2014; 9:e101048. [PMID: 25089637 PMCID: PMC4121069 DOI: 10.1371/journal.pone.0101048] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 06/03/2014] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Vaccines against HPV16/18 are approved for use in females and males but most countries currently have female-only programs. Cultural and geographic factors associated with HPV vaccine uptake might also influence sexual partner choice; this might impact post-vaccination outcomes. Our aims were to examine the population-level impact of adding males to HPV vaccination programs if factors influencing vaccine uptake also influence partner choice, and additionally to quantify how this changes the post-vaccination distribution of disease between subgroups, using incident infections as the outcome measure. METHODS A dynamic model simulated vaccination of pre-adolescents in two scenarios: 1) vaccine uptake was correlated with factors which also affect sexual partner choice ("correlated"); 2) vaccine uptake was unrelated to these factors ("unrelated"). Coverage and degree of heterogeneity in uptake were informed by observed data from Australia and the USA. Population impact was examined via the effect on incident HPV16 infections. The rate ratio for post-vaccination incident HPV16 in the lowest compared to the highest coverage subgroup (RR(L)) was calculated to quantify between-group differences in outcomes. RESULTS The population-level incremental impact of adding males was lower if vaccine uptake was "correlated", however the difference in population-level impact was extremely small (<1%) in the Australia and USA scenarios, even under the conservative and extreme assumption that subgroups according to coverage did not mix at all sexually. At the subgroup level, "correlated" female-only vaccination resulted in RR(L)= 1.9 (Australia) and 1.5 (USA) in females, and RR(L)= 1.5 and 1.3 in males. "Correlated" both-sex vaccination increased RR(L) to 4.2 and 2.1 in females and 3.9 and 2.0 in males in the Australia and USA scenarios respectively. CONCLUSIONS The population-level incremental impact of male vaccination is unlikely to be substantially impacted by feasible levels of heterogeneity in uptake. However, these findings emphasize the continuing importance of prioritizing high coverage across all groups in HPV vaccination programs in terms of achieving equality of outcomes.
Collapse
Affiliation(s)
- Megan A. Smith
- School of Public Health, The University of Sydney, Sydney, Australia
- Prince of Wales Clinical School, UNSW Australia, Sydney, Australia
| | - Karen Canfell
- Prince of Wales Clinical School, UNSW Australia, Sydney, Australia
| |
Collapse
|
31
|
Harper DM, Alexander NM, Ahern DA, Comes JC, Smith MS, Heutinck MA, Handley SM. Women have a preference for their male partner to be HPV vaccinated. PLoS One 2014; 9:e97119. [PMID: 24828237 PMCID: PMC4020771 DOI: 10.1371/journal.pone.0097119] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Accepted: 04/09/2014] [Indexed: 01/01/2023] Open
Abstract
Background Peer influence and social networking can change female adolescent and young adult behavior. Peer influence on preferences for male human papillomavirus (HPV) vaccination has not been documented. The primary aim of this study was to determine if women had preferences about male sexual partner HPV vaccination receipt. Methods and Findings A prospective survey of women 18–26 years of age was conducted at an urban university student health clinic. Education about the two HPV vaccines, cervical cancer and genital warts was provided. Women self-reported their demographic and medical history data, as well as their own preferences for HPV vaccine and their preferences for their male partner HPV vaccine using a 5 point Likert scale. 601 women, mean age of 21.5 years (SD 2.4), participated between 2011 and 2012. Nearly 95% of respondents were heterosexual; condoms and contraceptives were used in over half of the population. Regardless of the woman's vaccination status, women had significantly higher (strongly agree/agree) preferences for the male partner being vaccinated with HPV4 than not caring if he was vaccinated (63.6% vs. 13.1%, p<0.001). This preference was repeated for sexual risk factors and past reproductive medical history. Women who received HPV4 compared to those choosing HPV2 had a significantly lower proportion of preferences for not caring if the male partner was vaccinated (13% vs. 22%, p = 0.015). Conclusions Women preferred a HPV vaccinated male partner. Peer messaging might change the male HPV vaccination uptake.
Collapse
Affiliation(s)
- Diane Medved Harper
- Department of Biomedical and Health Informatics, University of Missouri Kansas City School of Medicine, Kansas City, Missouri, United States of America
- Department of Community and Family Medicine, University of Missouri Kansas City School of Medicine, Kansas City, Missouri, United States of America
- Department of Obstetrics and Gynecology, University of Missouri Kansas City School of Medicine, Kansas City, Missouri, United States of America
- * E-mail:
| | - Natalie Marya Alexander
- Department of Family Medicine, Kansas City University of Medicine and Biosciences, Kansas City, Missouri, United States of America
| | - Debra Ann Ahern
- Department of Community and Family Medicine, University of Missouri Kansas City School of Medicine, Kansas City, Missouri, United States of America
| | - Johanna Claire Comes
- University of Missouri Kansas City Student Health and Wellness, University of Missouri-Kansas City, Kansas City, Missouri, United States of America
| | - Melissa Smith Smith
- University of Missouri Kansas City Student Health and Wellness, University of Missouri-Kansas City, Kansas City, Missouri, United States of America
| | - Melinda Ann Heutinck
- University of Missouri Kansas City Student Health and Wellness, University of Missouri-Kansas City, Kansas City, Missouri, United States of America
| | - Sandra Martin Handley
- University of Missouri Kansas City Student Health and Wellness, University of Missouri-Kansas City, Kansas City, Missouri, United States of America
| |
Collapse
|
32
|
Huppert A, Katriel G. Mathematical modelling and prediction in infectious disease epidemiology. Clin Microbiol Infect 2014; 19:999-1005. [PMID: 24266045 DOI: 10.1111/1469-0691.12308] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We discuss to what extent disease transmission models provide reliable predictions. The concept of prediction is delineated as it is understood by modellers, and illustrated by some classic and recent examples. A precondition for a model to provide valid predictions is that the assumptions underlying it correspond to the reality, but such correspondence is always limited—all models are simplifications of reality. A central tenet of the modelling enterprise is what we may call the ‘robustness thesis’: a model whose assumptions approximately correspond to reality will make predictions that are approximately valid. To examine which of the predictions made by a model are trustworthy, it is essential to examine the outcomes of different models. Thus, if a highly simplified model makes a prediction, and if the same or a very similar prediction is made by a more elaborate model that includes some mechanisms or details that the first model did not, then we gain some confidence that the prediction is robust. An important benefit derived from mathematical modelling activity is that it demands transparency and accuracy regarding our assumptions, thus enabling us to test our understanding of the disease epidemiology by comparing model results and observed patterns. Models can also assist in decision-making by making projections regarding important issues such as intervention-induced changes in the spread of disease.
Collapse
|
33
|
Prevention of HPV-related cancers in Norway: cost-effectiveness of expanding the HPV vaccination program to include pre-adolescent boys. PLoS One 2014; 9:e89974. [PMID: 24651645 PMCID: PMC3961226 DOI: 10.1371/journal.pone.0089974] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Accepted: 01/25/2014] [Indexed: 01/27/2023] Open
Abstract
Background Increasingly, countries have introduced female vaccination against human papillomavirus (HPV), causally linked to several cancers and genital warts, but few have recommended vaccination of boys. Declining vaccine prices and strong evidence of vaccine impact on reducing HPV-related conditions in both women and men prompt countries to reevaluate whether HPV vaccination of boys is warranted. Methods A previously-published dynamic model of HPV transmission was empirically calibrated to Norway. Reductions in the incidence of HPV, including both direct and indirect benefits, were applied to a natural history model of cervical cancer, and to incidence-based models for other non-cervical HPV-related diseases. We calculated the health outcomes and costs of the different HPV-related conditions under a gender-neutral vaccination program compared to a female-only program. Results Vaccine price had a decisive impact on results. For example, assuming 71% coverage, high vaccine efficacy and a reasonable vaccine tender price of $75 per dose, we found vaccinating both girls and boys fell below a commonly cited cost-effectiveness threshold in Norway ($83,000/quality-adjusted life year (QALY) gained) when including vaccine benefit for all HPV-related diseases. However, at the current market price, including boys would not be considered ‘good value for money.’ For settings with a lower cost-effectiveness threshold ($30,000/QALY), it would not be considered cost-effective to expand the current program to include boys, unless the vaccine price was less than $36/dose. Increasing vaccination coverage to 90% among girls was more effective and less costly than the benefits achieved by vaccinating both genders with 71% coverage. Conclusions At the anticipated tender price, expanding the HPV vaccination program to boys may be cost-effective and may warrant a change in the current female-only vaccination policy in Norway. However, increasing coverage in girls is uniformly more effective and cost-effective than expanding vaccination coverage to boys and should be considered a priority.
Collapse
|
34
|
Dochez C, Bogers JJ, Verhelst R, Rees H. HPV vaccines to prevent cervical cancer and genital warts: an update. Vaccine 2014; 32:1595-601. [DOI: 10.1016/j.vaccine.2013.10.081] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 10/24/2013] [Accepted: 10/24/2013] [Indexed: 12/12/2022]
|
35
|
Impact of vaccination on 14 high-risk HPV type infections: a mathematical modelling approach. PLoS One 2013; 8:e72088. [PMID: 24009669 PMCID: PMC3756967 DOI: 10.1371/journal.pone.0072088] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Accepted: 07/07/2013] [Indexed: 11/19/2022] Open
Abstract
The development of high-risk human papillomavirus (hrHPV) infection to cervical cancer is a complicated process. We considered solely hrHPV infections, thus avoiding the confounding effects of disease progression, screening, and treatments. To analyse hrHPV epidemiology and to estimate the overall impact of vaccination against infections with hrHPVs, we developed a dynamic compartmental transmission model for single and multiple infections with 14 hrHPV types. The infection-related parameters were estimated using population-based sexual behaviour and hrHPV prevalence data from Finland. The analysis disclosed the important role of persistent infections in hrHPV epidemiology, provided further evidence for a significant natural immunity, and demonstrated the dependence of transmission probability estimates on the model structure. The model predicted that vaccinating girls at 80% coverage will result in a 55% reduction in the overall hrHPV prevalence and a higher 65% reduction in the prevalence of persistent hrHPV infections in females. In males, the reduction will be 42% in the hrHPV prevalence solely by the herd effect from the 80% coverage in girls. If such high coverage among girls is not reached, it is still possible to reduce the female hrHPV prevalence indirectly by the herd effect if also boys are included in the vaccination program. On the other hand, any herd effects in older unvaccinated cohorts were minor. Limiting the epidemiological model to infection yielded improved understanding of the hrHPV epidemiology and of mechanisms with which vaccination impacts on hrHPV infections.
Collapse
|
36
|
Drolet M, Boily MC, Van de Velde N, Franco EL, Brisson M. Vaccinating Girls and Boys with Different Human Papillomavirus Vaccines: Can It Optimise Population-Level Effectiveness? PLoS One 2013; 8:e67072. [PMID: 23840589 PMCID: PMC3694081 DOI: 10.1371/journal.pone.0067072] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Accepted: 05/13/2013] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Decision-makers may consider vaccinating girls and boys with different HPV vaccines to benefit from their respective strengths; the quadrivalent (HPV4) prevents anogenital warts (AGW) whilst the bivalent (HPV2) may confer greater cross-protection. We compared, to a girls-only vaccination program with HPV4, the impact of vaccinating: 1) both genders with HPV4, and 2) boys with HPV4 and girls with HPV2. METHODS We used an individual-based transmission-dynamic model of heterosexual HPV infection and diseases. Our base-case scenario assumed lifelong efficacy of 100% against vaccine types, and 46,29,8,18,6% and 77,43,79,8,0% efficacy against HPV-31,-33,-45,-52,-58 for HPV4 and HPV2, respectively. RESULTS Assuming 70% vaccination coverage and lifelong cross-protection, vaccinating boys has little additional benefit on AGW prevention, irrespective of the vaccine used for girls. Furthermore, using HPV4 for boys and HPV2 for girls produces greater incremental reductions in SCC incidence than using HPV4 for both genders (12 vs 7 percentage points). At 50% vaccination coverage, vaccinating boys produces incremental reductions in AGW of 17 percentage points if both genders are vaccinated with HPV4, but increases female incidence by 16 percentage points if girls are switched to HPV2 (heterosexual male incidence is incrementally reduced by 24 percentage points in both scenarios). Higher incremental reductions in SCC incidence are predicted when vaccinating boys with HPV4 and girls with HPV2 versus vaccinating both genders with HPV4 (16 vs 12 percentage points). Results are sensitive to vaccination coverage and the relative duration of protection of the vaccines. CONCLUSION Vaccinating girls with HPV2 and boys with HPV4 can optimize SCC prevention if HPV2 has higher/longer cross-protection, but can increase AGW incidence if vaccination coverage is low among boys.
Collapse
Affiliation(s)
- Mélanie Drolet
- Centre de recherche du CHU de Québec, Hôpital Saint-Sacrement, Québec, Canada
- Département de médecine sociale et préventive, Université Laval, Québec, Canada
| | - Marie-Claude Boily
- Department of Infectious Disease Epidemiology, Imperial College, London, United Kindom
| | - Nicolas Van de Velde
- Centre de recherche du CHU de Québec, Hôpital Saint-Sacrement, Québec, Canada
- Département de médecine sociale et préventive, Université Laval, Québec, Canada
| | - Eduardo L. Franco
- Division of Cancer Epidemiology, McGill University, Montreal, Canada
| | - Marc Brisson
- Centre de recherche du CHU de Québec, Hôpital Saint-Sacrement, Québec, Canada
- Département de médecine sociale et préventive, Université Laval, Québec, Canada
- Department of Infectious Disease Epidemiology, Imperial College, London, United Kindom
| |
Collapse
|
37
|
|
38
|
Horn J, Damm O, Kretzschmar MEE, Deleré Y, Wichmann O, Kaufmann AM, Garbe E, Krämer A, Greiner W, Mikolajczyk RT. Estimating the long-term effects of HPV vaccination in Germany. Vaccine 2013; 31:2372-80. [PMID: 23518405 DOI: 10.1016/j.vaccine.2013.03.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 02/22/2013] [Accepted: 03/04/2013] [Indexed: 12/15/2022]
Abstract
In Germany, vaccination against the most oncogenic HPV types 16/18 is recommended by the Standing Committee on Vaccination (STIKO) for 12-17 year old girls since March 2007. We developed a dynamic mathematical model for the natural history and transmission of HPV infections to estimate the impact of vaccination on incidence and mortality of cervical cancer and its pre-stages, and on anogenital warts. We focused on an extensive model calibration to epidemiologic data for all stages of the natural history model as well as on a detailed implementation of cervical cancer screening modalities in Germany. Our model predicts first a substantial reduction of cervical cancer incidence and mortality over the next 30 years, which is mainly attributable to an increase in screening participation in the 1990s and not to HPV vaccination, followed by a further reduction attributable to vaccination. Over the next 100 years, HPV vaccination will prevent approximately 37% of cervical cancer cases even if vaccination coverage is only 50% (as currently observed in Germany). Consideration of cross-protection results in a further reduction of approximately 7% of all cervical cancer cases for the bivalent and about 5% for the quadrivalent vaccine in our model. Vaccination of boys was only reasonable if moderate to high vaccination coverage in girls was not achieved. Strategies should be implemented in Germany to increase HPV vaccination coverage among girls thereby making better use of the demonstrated benefits of the vaccine.
Collapse
Affiliation(s)
- J Horn
- Department of Epidemiology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
39
|
Jit M, Levin C, Brisson M, Levin A, Resch S, Berkhof J, Kim J, Hutubessy R. Economic analyses to support decisions about HPV vaccination in low- and middle-income countries: a consensus report and guide for analysts. BMC Med 2013; 11:23. [PMID: 23363734 PMCID: PMC3582485 DOI: 10.1186/1741-7015-11-23] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Accepted: 01/30/2013] [Indexed: 11/10/2022] Open
Abstract
Low- and middle-income countries need to consider economic issues such as cost-effectiveness, affordability and sustainability before introducing a program for human papillomavirus (HPV) vaccination. However, many such countries lack the technical capacity and data to conduct their own analyses. Analysts informing policy decisions should address the following questions: 1) Is an economic analysis needed? 2) Should analyses address costs, epidemiological outcomes, or both? 3) If costs are considered, what sort of analysis is needed? 4) If outcomes are considered, what sort of model should be used? 5) How complex should the analysis be? 6) How should uncertainty be captured? 7) How should model results be communicated? Selecting the appropriate analysis is essential to ensure that all the important features of the decision problem are correctly represented, but that the analyses are not more complex than necessary. This report describes the consensus of an expert group convened by the World Health Organization, prioritizing key issues to be addressed when considering economic analyses to support HPV vaccine introduction in these countries.
Collapse
Affiliation(s)
- Mark Jit
- Modelling and Economics Unit, Health Protection Agency, 61 Colindale Avenue, London NW9 5EQ, UK
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Carol Levin
- PATH, 2201 Westlake Avenue, Suite 200 Seattle, WA 98121 USA
| | - Marc Brisson
- Centre de recherche du CHU de Québec, Hôpital Saint-Sacrement, 1050 Chemin Sainte-Foy, Québec, G1S 4L8, Canada
- Department of Infectious Disease Epidemiology, Imperial College, London, UK
| | - Ann Levin
- Independent Consultant, 6414 Hollins Dr., Bethesda, MD 20817 USA
| | - Stephen Resch
- Center for Health Decision Science, Harvard School of Public Health, 718 Huntington Ave, Boston, MA 02130, USA
| | - Johannes Berkhof
- Department of Epidemiology and Biostatistics, VU University Medical Centre, PO box 7057, 1007 MB Amsterdam, The Netherlands
| | - Jane Kim
- Center for Health Decision Science, Harvard School of Public Health, 718 Huntington Ave, Boston, MA 02130, USA
| | - Raymond Hutubessy
- Initiative for Vaccine Research, World Health Organization, 20 Avenue Appia, CH-1211 Geneva, Switzerland
| |
Collapse
|
40
|
Marty R, Roze S, Bresse X, Largeron N, Smith-Palmer J. Estimating the clinical benefits of vaccinating boys and girls against HPV-related diseases in Europe. BMC Cancer 2013; 13:10. [PMID: 23298365 PMCID: PMC3561184 DOI: 10.1186/1471-2407-13-10] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Accepted: 12/28/2012] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND HPV is related to a number of cancer types, causing a considerable burden in both genders in Europe. Female vaccination programs can substantially reduce the incidence of HPV-related diseases in women and, to some extent, men through herd immunity. The objective was to estimate the incremental benefit of vaccinating boys and girls using the quadrivalent HPV vaccine in Europe versus girls-only vaccination. Incremental benefits in terms of reduction in the incidence of HPV 6, 11, 16 and 18-related diseases (including cervical, vaginal, vulvar, anal, penile, and head and neck carcinomas and genital warts) were assessed. METHODS The analysis was performed using a model constructed in Microsoft(®)Excel, based on a previously-published dynamic transmission model of HPV vaccination and published European epidemiological data on incidence of HPV-related diseases. The incremental benefits of vaccinating 12-year old girls and boys versus girls-only vaccination was assessed (70% vaccine coverage were assumed for both). Sensitivity analyses around vaccine coverage and duration of protection were performed. RESULTS Compared with screening alone, girls-only vaccination led to 84% reduction in HPV 16/18-related carcinomas in females and a 61% reduction in males. Vaccination of girls and boys led to a 90% reduction in HPV 16/18-related carcinomas in females and 86% reduction in males versus screening alone. Relative to a girls-only program, vaccination of girls and boys led to a reduction in female and male HPV-related carcinomas of 40% and 65%, respectively and a reduction in the incidence of HPV 6/11-related genital warts of 58% for females and 71% for males versus girls-only vaccination. CONCLUSIONS In Europe, the vaccination of 12-year old boys and girls against HPV 6, 11, 16 and 18 would be associated with substantial additional clinical benefits in terms of reduced incidence of HPV-related genital warts and carcinomas versus girls-only vaccination. The incremental benefits of adding boys vaccination are highly dependent on coverage in girls. Therefore, further analyses should be performed taking into account the country-specific situation. In addition to clinical benefits, substantial economic benefits are also anticipated and warrant further investigation as do the social and ethical implications of including boys in vaccination programs.
Collapse
Affiliation(s)
- Rémi Marty
- HEVA, 186 Avenue Thiers, Lyon, 69006, France.
| | | | | | | | | |
Collapse
|
41
|
Brisson M, Drolet M, Malagón T. Inequalities in Human Papillomavirus (HPV)–Associated Cancers: Implications for the Success of HPV Vaccination. ACTA ACUST UNITED AC 2013; 105:158-61. [DOI: 10.1093/jnci/djs638] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
42
|
Althaus CL, Heijne JCM, Herzog SA, Roellin A, Low N. Individual and population level effects of partner notification for Chlamydia trachomatis. PLoS One 2012; 7:e51438. [PMID: 23251534 PMCID: PMC3520891 DOI: 10.1371/journal.pone.0051438] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Accepted: 10/31/2012] [Indexed: 01/08/2023] Open
Abstract
Partner notification (PN or contact tracing) is an important aspect of treating bacterial sexually transmitted infections (STIs), such as Chlamydia trachomatis. It facilitates the identification of new infected cases that can be treated through individual case management. PN also acts indirectly by limiting onward transmission in the general population. However, the impact of PN, both at the level of individuals and the population, remains unclear. Since it is difficult to study the effects of PN empirically, mathematical and computational models are useful tools for investigating its potential as a public health intervention. To this end, we developed an individual-based modeling framework called Rstisim. It allows the implementation of different models of STI transmission with various levels of complexity and the reconstruction of the complete dynamic sexual partnership network over any time period. A key feature of this framework is that we can trace an individual's partnership history in detail and investigate the outcome of different PN strategies for C. trachomatis. For individual case management, the results suggest that notifying three or more partners from the preceding 18 months yields substantial numbers of new cases. In contrast, the successful treatment of current partners is most important for preventing re-infection of index cases and reducing further transmission of C. trachomatis at the population level. The findings of this study demonstrate the difference between individual and population level outcomes of public health interventions for STIs.
Collapse
Affiliation(s)
- Christian L Althaus
- Institute of Social and Preventive Medicine (ISPM), University of Bern, Bern, Switzerland.
| | | | | | | | | |
Collapse
|
43
|
Abstract
It appears to be entirely appropriate for pharmacists to administer vaccinations if restricted to a limited number of vaccines and a well-defined set of recipients. Recommended types of vaccines would be inert vaccines with no contraindications, including flu vaccines, booster shots for diphtheria, tetanus, pertussis, and polio, and HPV vaccines for the prevention of cervical cancer. Recipients targeted for these types of vaccinations would only be adults and adolescents. In addition, pharmacist-administered vaccinations would not be recommended for pregnant women, people with immunodeficiencies, chronic diseases, or cystic fibrosis, people under treatment (anticoagulants) or with known allergies, and haemophiliacs. They would not be recommended either when needed in the context of employment and for traveling abroad. Training is essential to manage the successful implementation of a pharmacist-administered vaccination program (maintaining cold storage, monitoring, space allocation, vaccination administration process, preventive measures, quick recognition and management of anaphylactic chock…).
Collapse
Affiliation(s)
- J Freney
- UMR 5557 - CNRS écologie microbienne.
| |
Collapse
|
44
|
Canfell K, Chesson H, Kulasingam SL, Berkhof J, Diaz M, Kim JJ. Modeling preventative strategies against human papillomavirus-related disease in developed countries. Vaccine 2012; 30 Suppl 5:F157-67. [PMID: 23199959 PMCID: PMC3783354 DOI: 10.1016/j.vaccine.2012.06.091] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 06/11/2012] [Accepted: 06/13/2012] [Indexed: 02/08/2023]
Abstract
Over the last 5 years, prophylactic vaccination against human papillomavirus (HPV) in pre-adolescent females has been introduced in most developed countries, supported by modeled evaluations that have almost universally found vaccination of pre-adolescent females to be cost-effective. Studies to date suggest that vaccination of pre-adolescent males may also be cost-effective at a cost per vaccinated individual of ~US$400-500 if vaccination coverage in females cannot be increased above ~50%; but if it is possible, increasing coverage in females appears to be a better return on investment. Comparative evaluation of the quadrivalent (HPV16,18,6,11) and bivalent (HPV16,18) vaccines centers around the potential trade-off between protection against anogenital warts and vaccine-specific levels of cross-protection against infections not targeted by the vaccines. Future evaluations will also need to consider the cost-effectiveness of a next generation nonavalent vaccine designed to protect against ~90% of cervical cancers. The timing of the effect of vaccination on cervical screening programs will be country-specific and will depend on vaccination catch-up age range and coverage and the age at which screening starts. Initial evaluations suggest that if screening remains unchanged, it will be less cost-effective in vaccinated compared to unvaccinated women but, in the context of current vaccines, will remain an important prevention method. Comprehensive evaluation of new approaches to screening will need to consider the population-level effects of vaccination over time. New screening strategies of particular interest include delaying the start age of screening, increasing the screening interval and switching to primary HPV screening. Future evaluations of screening will also need to focus on the effects of disparities in screening and vaccination uptake, the potential effects of vaccination on screening participation, and the effects of imperfect compliance with screening recommendations. This article forms part of a special supplement entitled "Comprehensive Control of HPV Infections and Related Diseases" Vaccine Volume 30, Supplement 5, 2012.
Collapse
Affiliation(s)
- Karen Canfell
- Cancer Epidemiology Research Unit, Cancer Council NSW, Sydney, Australia.
| | | | | | | | | | | |
Collapse
|
45
|
Botha MH, Dochez C. Introducing human papillomavirus vaccines into the health system in South Africa. Vaccine 2012; 30 Suppl 3:C28-34. [DOI: 10.1016/j.vaccine.2012.03.032] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2011] [Revised: 02/20/2012] [Accepted: 03/15/2012] [Indexed: 10/27/2022]
|