Mark Jit

Mark Jit
Mark Jit
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Chair and Professor of the Department of Global and Environmental Health

Professional overview

Mark Jit is the inaugural chair and a professor in the Department of Global and Environmental Health. He was formerly head of the Department of Infectious Disease Epidemiology & Dynamics and co-director of the Global Health Economics Centre (GHECO) at the London School of Hygiene & Tropical Medicine (LSHTM). He holds honorary appointments at LSHTM as well as the University of Hong Kong (HKU) and the National University of Singapore (NUS).

Dr. Jit’s research focuses on epidemiological and economic modeling of vaccines to support evidence-based public health decision making. He has published papers covering a range of vaccine-preventable or potentially vaccine-preventable diseases including COVID-19, measles, HPV, pneumococcus, rotavirus, influenza, Group B Streptococcus, dengue, EV71 and RSV as well as methodological papers advancing the ways vaccines are evaluated. This work has influenced many of the major changes to immunization policy in countries around the world. Dr. Jit has served on a number of expert advisory committees in the UK as well as for international organizations such as the World Health Organization. He also organises or contributes to academic and professional courses on vaccine modeling, economics and decision science around the world.

Dr. Jit received his BSc and PhD in Mathematics from University College London, specializing in mathematical biology, and a Master of Public Health degree from King’s College London.

Visit Dr. Jit's Google Scholar's page to learn more about his research portfolio.

Education

BSc, Mathematics, University College London
PhD, Mathematics, University College London
MPH, Public Health, King's College London

Honors and awards

Clarivate Highly Cited Researcher (20222023)
Fellow of the Academy of Medical Sciences (2023)
Training Fund Award, Health Protection Agency (2007)
Andrew Rosen Prize, University College London (1999)
Institute of Mathematics and its Applications Award (1998)
Departmental Research Studentship, University College London (1998)
Student Union Commendation, University College London (1997)
Fillon Prize, University College London (1996)
Pathfinder Award, University College London (1995)

Publications

Publications

Social contact patterns relevant to the spread of respiratory infectious diseases in Hong Kong

Leung, K., Jit, M., Lau, E. H., & Wu, J. T. (n.d.).

Publication year

2017

Journal title

Scientific reports

Volume

7
Abstract
Abstract
The spread of many respiratory infections is determined by contact patterns between infectious and susceptible individuals in the population. There are no published data for quantifying social contact patterns relevant to the spread of respiratory infectious diseases in Hong Kong which is a hotspot for emerging infectious diseases due to its high population density and connectivity in the air transportation network. We adopted a commonly used diary-based design to conduct a social contact survey in Hong Kong in 2015/16 using both paper and online questionnaires. Participants using paper questionnaires reported more contacts and longer contact duration than those using online questionnaires. Participants reported 13 person-hours of contact and 8 contacts per day on average, which decreased over age but increased with household size, years of education and income level. Prolonged and frequent contacts, and contacts at home, school and work were more likely to involve physical contacts. Strong age-assortativity was observed in all age groups. We evaluated the characteristics of social contact patterns relevant to the spread of respiratory infectious diseases in Hong Kong. Our findings could help to improve the design of future social contact surveys, parameterize transmission models of respiratory infectious diseases, and inform intervention strategies based on model outputs.

The impact of influenza on the health related quality of life in China: An EQ-5D survey

Yang, J., Jit, M., Zheng, Y., Feng, L., Liu, X., Wu, J. T., & Yu, H. (n.d.).

Publication year

2017

Journal title

BMC Infectious Diseases

Volume

17

Issue

1
Abstract
Abstract
Background: Influenza causes considerable morbidity and mortality in China, but its impact on the health-related quality of life (HRQoL) has not been previously measured. Methods: We conducted a retrospective telephone survey to assess the impact of influenza on the HRQoL among outpatients and inpatients using the EuroQoL EQ-5D-3 L instrument. Participants were individuals with laboratory-confirmed influenza infection registered by the National Influenza-like-illness Surveillance Network in 2013. Results: We interviewed 839 of 11,098 eligible influenza patients. After excluding those who were unable to complete the HRQoL for the registered influenza episode, 778 patients were included in the analysis. Both outpatients (n = 529) and inpatients (n = 249) most commonly reported problems with pain/discomfort (71.8% of outpatients and 71.9% of inpatients) and anxiety/depression (62.0% of outpatients and 75.1% of inpatients). For individual influenza outpatients, the mean health utility was 0.6142 (SD 0.2006), and the average quality adjusted life days (QALD) loss was 1.62 (SD 1.84) days. The HRQoL of influenza inpatients was worse (mean health utility 0.5851, SD 0.2197; mean QALD loss 3.51 days, SD 4.25) than that of outpatients (p < 0.05). The presence of underlying medical conditions lowered the HRQoL for both outpatients and inpatients (p < 0.05). Conclusions: Influenza illness had a substantial impact on HRQoL. QALD loss due to an acute influenza episode in younger children was comparable to that due to enterovirus A71-associated hand, foot and mouth disease. Our findings are key inputs into disease burden estimates and cost-effectiveness evaluations of influenza-related interventions in China.

Adding interventions to mass measles vaccinations in India

Johri, M., Verguet, S., Morris, S. K., Sharma, J. K., Ram, U., Gauvreau, C., Jones, E., Jha, P., & Jit, M. (n.d.).

Publication year

2016

Journal title

Bulletin of the World Health Organization

Volume

94

Issue

10

Page(s)

718-727
Abstract
Abstract
Objective To quantify the impact on mortality of offering a hypothetical set of technically feasible, high-impact interventions for maternal and child survival during India’s 2010-2013 measles supplementary immunization activity. Methods We developed Lives Saved Tool models for 12 Indian states participating in the supplementary immunization, based on state- and sex-specific data on mortality from India’s Million Deaths Study and on health services coverage from Indian household surveys. Potential add-on interventions were identified through a literature review and expert consultations. We quantified the number of lives saved for a campaign offering measles vaccine alone versus a campaign offering measles vaccine with six add-on interventions (nutritional screening and complementary feeding for children, vitamin A and zinc supplementation for children, multiple micronutrient and calcium supplementation in pregnancy, and free distribution of insecticide-treated bednets). Findings The measles vaccination campaign saved an estimated 19 016 lives of children younger than 5 years. A hypothetical campaign including measles vaccine with add-on interventions was projected to save around 73 900 lives (range: 70 200-79 300), preventing 73 700 child deaths (range: 70 000-79 000) and 300 maternal deaths (range: 200-400). The most effective interventions in the whole package were insecticide-treated bednets, measles vaccine and preventive zinc supplementation. Girls accounted for 66% of expected lives saved (12 712/19 346) for the measles vaccine campaign, and 62% of lives saved (45 721/74 367) for the hypothetical campaign including addon interventions. Conclusion In India, a measles vaccination campaign including feasible, high-impact interventions could substantially increase the number of lives saved and mitigate gender-related inequities in child mortality.

Assessing dengue vaccination impact: Model challenges and future directions

Recker, M., Vannice, K., Hombach, J., Jit, M., & Simmons, C. P. (n.d.).

Publication year

2016

Journal title

Vaccine

Volume

34

Issue

38

Page(s)

4461-4465
Abstract
Abstract
In response to the sharp rise in the global burden caused by dengue virus (DENV) over the last few decades, the WHO has set out three specific key objectives in its disease control strategy: (i) to estimate the true burden of dengue by 2015; (ii) a reduction in dengue mortality by at least 50% by 2020 (used as a baseline); and (iii) a reduction in dengue morbidity by at least 25% by 2020. Although various elements will all play crucial parts in achieving this goal, from diagnosis and case management to integrated surveillance and outbreak response, sustainable vector control, vaccine implementation and finally operational and implementation research, it seems clear that new tools (e.g. a safe and effective vaccine and/or effective vector control) are key to success. The first dengue vaccine was licensed in December 2015, Dengvaxia® (CYD-TDV) developed by Sanofi Pasteur. The WHO has provided guidance on the use of CYD-TDV in endemic countries, for which there are a variety of considerations beyond the risk–benefit evaluation done by regulatory authorities, including public health impact and cost-effectiveness. Population-level vaccine impact and economic and financial aspects are two issues that can potentially be considered by means of mathematical modelling, especially for new products for which empirical data are still lacking. In December 2014 a meeting was convened by the WHO in order to revisit the current status of dengue transmission models and their utility for public health decision-making. Here, we report on the main points of discussion and the conclusions of this meeting, as well as next steps for maximising the use of mathematical models for vaccine decision-making.

Clustering of contacts relevant to the spread of infectious disease

Xiao, X., Van Hoek, A. J., Kenward, M. G., Melegaro, A., & Jit, M. (n.d.).

Publication year

2016

Journal title

Epidemics

Volume

17

Page(s)

1-9
Abstract
Abstract
Objective Infectious disease spread depends on contact rates between infectious and susceptible individuals. Transmission models are commonly informed using empirically collected contact data, but the relevance of different contact types to transmission is still not well understood. Some studies select contacts based on a single characteristic such as proximity (physical/non-physical), location, duration or frequency. This study aimed to explore whether clusters of contacts similar to each other across multiple characteristics could better explain disease transmission. Methods Individual contact data from the POLYMOD survey in Poland, Great Britain, Belgium, Finland and Italy were grouped into clusters by the k medoids clustering algorithm with a Manhattan distance metric to stratify contacts using all four characteristics. Contact clusters were then used to fit a transmission model to sero-epidemiological data for varicella-zoster virus (VZV) in each country. Results and discussion Across the five countries, 9–15 clusters were found to optimise both quality of clustering (measured using average silhouette width) and quality of fit (measured using several information criteria). Of these, 2–3 clusters were most relevant to VZV transmission, characterised by (i) 1–2 clusters of age-assortative contacts in schools, (ii) a cluster of less age-assortative contacts in non-school settings. Quality of fit was similar to using contacts stratified by a single characteristic, providing validation that single stratifications are appropriate. However, using clustering to stratify contacts using multiple characteristics provided insight into the structures underlying infection transmission, particularly the role of age-assortative contacts, involving school age children, for VZV transmission between households.

Current global pricing for human papillomavirus vaccines brings the greatest economic benefits to rich countries

Herlihy, N., Hutubessy, R., & Jit, M. (n.d.).

Publication year

2016

Journal title

Health Affairs

Volume

35

Issue

2

Page(s)

227-234
Abstract
Abstract
Vaccinating females against human papillomavirus (HPV) prior to the debut of sexual activity is an effective way to prevent cervical cancer, yet vaccine uptake in low- and middle-income countries has been hindered by high vaccine prices. We created an economic model to estimate the distribution of the economic surplus-the sum of all health and economic benefits of a vaccine, minus the costs of development, production, and distribution-among different country income groups and manufacturers for a cohort of twelve-year-old females in 2012. We found that manufacturers may have received economic returns worth five times their original investment in HPV vaccine development. Highincome countries gained the greatest economic surplus of any income category, realizing over five times more economic value per vaccinated female than low-income countries did. Subsidizing vaccine prices in lowand middle-income countries could both reduce financial barriers to vaccine adoption and still allow high-income countries to retain their economic surpluses and manufacturers to retain their profits.

Eurogin Roadmap 2015: How has HPV knowledge changed our practice: Vaccines

Brotherton, J. M., Jit, M., Gravitt, P. E., Brisson, M., Kreimer, A. R., Pai, S. I., Fakhry, C., Monsonego, J., & Franceschi, S. (n.d.).

Publication year

2016

Journal title

International Journal of Cancer

Volume

139

Issue

3

Page(s)

510-517
Abstract
Abstract
This review is one of two complementary reviews that have been prepared in the framework of the Eurogin Roadmap 2015 to evaluate how knowledge about HPV is changing practices in HPV infection and disease control through vaccination and screening. In this review of HPV vaccine knowledge, we present the most significant findings of the past year which have contributed to our knowledge of the two HPV prophylactic vaccines currently in widespread use and about the recently licensed nonavalent HPV vaccine. Whereas anal cancer is dealt with in the companion mini-review on screening, we also review here the rapidly evolving evidence regarding HPV-associated head and neck cancer and priority research areas.

Methodological Challenges to Economic Evaluations of Vaccines: Is a Common Approach Still Possible?

Jit, M., & Hutubessy, R. (n.d.).

Publication year

2016

Journal title

Applied Health Economics and Health Policy

Volume

14

Issue

3

Page(s)

245-252
Abstract
Abstract
Economic evaluation of vaccination is a key tool to inform effective spending on vaccines. However, many evaluations have been criticised for failing to capture features of vaccines which are relevant to decision makers. These include broader societal benefits (such as improved educational achievement, economic growth and political stability), reduced health disparities, medical innovation, reduced hospital beds pressures, greater peace of mind and synergies in economic benefits with non-vaccine interventions. Also, the fiscal implications of vaccination programmes are not always made explicit. Alternative methodological frameworks have been proposed to better capture these benefits. However, any broadening of the methodology for economic evaluation must also involve evaluations of non-vaccine interventions, and hence may not always benefit vaccines given a fixed health-care budget. The scope of an economic evaluation must consider the budget from which vaccines are funded, and the decision-maker’s stated aims for that spending to achieve.

Methods for Health Economic Evaluation of Vaccines and Immunization Decision Frameworks: A Consensus Framework from a European Vaccine Economics Community

Ultsch, B., Damm, O., Beutels, P., Bilcke, J., Brüggenjürgen, B., Gerber-Grote, A., Greiner, W., Hanquet, G., Hutubessy, R., Jit, M., Knol, M., Von Kries, R., Kuhlmann, A., Levy-Bruhl, D., Perleth, M., Postma, M., Salo, H., Siebert, U., Wasem, J., & Wichmann, O. (n.d.).

Publication year

2016

Journal title

PharmacoEconomics

Volume

34

Issue

3

Page(s)

227-244
Abstract
Abstract
Background: Incremental cost-effectiveness and cost-utility analyses [health economic evaluations (HEEs)] of vaccines are routinely considered in decision making on immunization in various industrialized countries. While guidelines advocating more standardization of such HEEs (mainly for curative drugs) exist, several immunization-specific aspects (e.g. indirect effects or discounting approach) are still a subject of debate within the scientific community. Objective: The objective of this study was to develop a consensus framework for HEEs of vaccines to support the development of national guidelines in Europe. Methods: A systematic literature review was conducted to identify prevailing issues related to HEEs of vaccines. Furthermore, European experts in the field of health economics and immunization decision making were nominated and asked to select relevant aspects for discussion. Based on this, a workshop was held with these experts. Aspects on ‘mathematical modelling’, ‘health economics’ and ‘decision making’ were debated in group-work sessions (GWS) to formulate recommendations and/or—if applicable—to state ‘pros’ and ‘contras’. Results: A total of 13 different aspects were identified for modelling and HEE: model selection, time horizon of models, natural disease history, measures of vaccine-induced protection, duration of vaccine-induced protection, indirect effects apart from herd protection, target population, model calibration and validation, handling uncertainty, discounting, health-related quality of life, cost components, and perspectives. For decision making, there were four aspects regarding the purpose and the integration of HEEs of vaccines in decision making as well as the variation of parameters within uncertainty analyses and the reporting of results from HEEs. For each aspect, background information and an expert consensus were formulated. Conclusions: There was consensus that when HEEs are used to prioritize healthcare funding, this should be done in a consistent way across all interventions, including vaccines. However, proper evaluation of vaccines implies using tools that are not commonly used for therapeutic drugs. Due to the complexity of and uncertainties around vaccination, transparency in the documentation of HEEs and during subsequent decision making is essential.

Modeling the impact of rubella vaccination in Vietnam

Vynnycky, E., Yoshida, L. M., Thanh Huyen, D. T., Trung, N. D., Toda, K., Van Cuong, N., Hong, D. T., Ariyoshi, K., Miyakawa, M., Moriuchi, H., Tho, L. H., Nguyen, H. A., Anh, D. D., Jit, M., & Hien, N. T. (n.d.).

Publication year

2016

Journal title

Human Vaccines and Immunotherapeutics

Volume

12

Issue

1

Page(s)

150-158
Abstract
Abstract
Supported by GAVI Alliance, measles-rubella vaccination was introduced in Vietnam in 2014, involving a mass campaign among 1–14 year olds and routine immunization of children aged 9 months. We explore the impact on the incidence of Congenital Rubella Syndrome (CRS) during 2013–2050 of this strategy and variants involving women aged 15–35 years. We use an age and sex-structured dynamic transmission model, set up using recently-collected seroprevalence data from Central Vietnam, and also consider different levels of transmission and contact patterns. If the serological profile resembles that in Central Vietnam, the planned vaccination strategy could potentially prevent 125,000 CRS cases by 2050 in Vietnam, despite outbreaks predicted in the meantime. Targeting the initial campaign at 15–35 year old women with or without children aged 9 months–14 years led to sustained reductions in incidence, unless levels of ongoing transmission were medium-high before vaccination started. Assumptions about contact greatly influenced predictions if the initial campaign just targeted 15–35 year old women and/or levels of ongoing transmission were medium-high. Given increased interest in rubella vaccination, resulting from GAVI Alliance funding, the findings are relevant for many countries.

Oral human papillomavirus infection in men who have sex with men: A systematic review and meta-analysis

King, E. M., Oomeer, S., Gilson, R., Copas, A., Beddows, S., Soldan, K., Jit, M., Edmunds, W. J., & Sonnenberg, P. (n.d.).

Publication year

2016

Journal title

PloS one

Volume

11

Issue

7
Abstract
Abstract
Background: The epidemiology of oral human papillomavirus (HPV) infection in men who have sex with men (MSM) differs from anogenital HPV infection. The impact of HPV vaccination has, to date, largely focussed on anogenital outcomes. Vaccination of MSM in the UK has been recommended and, if implemented, baseline estimates of oral HPV prevalence will be useful. Methods: We searched Medline, Embase and psycINFO databases for studies reporting prevalence, incidence, and clearance of oral HPV infection in MSM. We performed a random-effects meta-analysis and meta-regression on prevalence estimates and summarised within-study risk factors for oral HPV DNA detection and incidence/clearance rates. We also performed a meta-analysis of the effect of MSM on oral HPV prevalence compared to heterosexual men. Results: 26 publications were identified. The pooled prevalence of oral HPV16 from twelve estimates was 3.0% (95%CI 0.5-5.5) in HIV-negative and 4.7% (95%CI 2.1-7.3) in HIV-positive MSM. Median age of study participants explained 38% of heterogeneity (p<0.01) in HPV prevalence estimates (pooled = 17% and 29% in HIV-negative and HIV-positive, respectively; 22 estimates). Nine studies compared MSM to heterosexual men and found no difference in oral HPV prevalence (pooled OR 1.07 (95%CI 0.65-1.74)). The clearance rate was higher than incidence within studies. Type-specific concordance between oral and anogenital sites was rare. Conclusion: There was substantial heterogeneity between estimates of oral HPV prevalence in MSM populations that was partly explained by HIV status and median age.

Population-level impact, herd immunity, and elimination after human papillomavirus vaccination: a systematic review and meta-analysis of predictions from transmission-dynamic models

Brisson, M., Bénard, Élodie, Drolet, M., Bogaards, J. A., Baussano, I., Vänskä, S., Jit, M., Boily, M. C., Smith, M. A., Berkhof, J., Canfell, K., Chesson, H. W., Burger, E. A., Choi, Y. H., De Blasio, B. F., De Vlas, S. J., Guzzetta, G., Hontelez, J. A., Horn, J., … Walsh, C. (n.d.).

Publication year

2016

Journal title

The Lancet Public Health

Volume

1

Issue

1

Page(s)

e8-e17
Abstract
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.

Public health impact and cost-effectiveness of the RTS,S/AS01 malaria vaccine: A systematic comparison of predictions from four mathematical models

Penny, M. A., Verity, R., Bever, C. A., Sauboin, C., Galactionova, K., Flasche, S., White, M. T., Wenger, E. A., Van De Velde, N., Pemberton-Ross, P., Griffin, J. T., Smith, T. A., Eckhoff, P. A., Muhib, F., Jit, M., & Ghani, A. C. (n.d.).

Publication year

2016

Journal title

The Lancet

Volume

387

Issue

10016

Page(s)

367-375
Abstract
Abstract
Summary Background The phase 3 trial of the RTS,S/AS01 malaria vaccine candidate showed modest efficacy of the vaccine against Plasmodium falciparum malaria, but was not powered to assess mortality endpoints. Impact projections and cost-effectiveness estimates for longer timeframes than the trial follow-up and across a range of settings are needed to inform policy recommendations. We aimed to assess the public health impact and cost-effectiveness of routine use of the RTS,S/AS01 vaccine in African settings. Methods We compared four malaria transmission models and their predictions to assess vaccine cost-effectiveness and impact. We used trial data for follow-up of 32 months or longer to parameterise vaccine protection in the group aged 5-17 months. Estimates of cases, deaths, and disability-adjusted life-years (DALYs) averted were calculated over a 15 year time horizon for a range of levels of Plasmodium falciparum parasite prevalence in 2-10 year olds (PfPR2-10; range 3-65%). We considered two vaccine schedules: three doses at ages 6, 7·5, and 9 months (three-dose schedule, 90% coverage) and including a fourth dose at age 27 months (four-dose schedule, 72% coverage). We estimated cost-effectiveness in the presence of existing malaria interventions for vaccine prices of US$2-10 per dose. Findings In regions with a PfPR2-10 of 10-65%, RTS,S/AS01 is predicted to avert a median of 93940 (range 20490-126540) clinical cases and 394 (127-708) deaths for the three-dose schedule, or 116480 (31450-160410) clinical cases and 484 (189-859) deaths for the four-dose schedule, per 100000 fully vaccinated children. A positive impact is also predicted at a PfPR2-10 of 5-10%, but there is little impact at a prevalence of lower than 3%. At $5 per dose and a PfPR2-10 of 10-65%, we estimated a median incremental cost-effectiveness ratio compared with current interventions of $30 (range 18-211) per clinical case averted and $80 (44-279) per DALY averted for the three-dose schedule, and of $25 (16-222) and $87 (48-244), respectively, for the four-dose schedule. Higher ICERs were estimated at low PfPR2-10 levels. Interpretation We predict a significant public health impact and high cost-effectiveness of the RTS,S/AS01 vaccine across a wide range of settings. Decisions about implementation will need to consider levels of malaria burden, the cost-effectiveness and coverage of other malaria interventions, health priorities, financing, and the capacity of the health system to deliver the vaccine. Funding PATH Malaria Vaccine Initiative; Bill & Melinda Gates Foundation; Global Good Fund; Medical Research Council; UK Department for International Development; GAVI, the Vaccine Alliance; WHO.

Rotavirus vaccines contribute towards universal health coverage in a mixed public–private healthcare system

Loganathan, T., Jit, M., Hutubessy, R., Ng, C. W., Lee, W. S., & Verguet, S. (n.d.).

Publication year

2016

Journal title

Tropical Medicine and International Health

Volume

21

Issue

11

Page(s)

1458-1467
Abstract
Abstract
Objectives: To evaluate rotavirus vaccination in Malaysia from the household's perspective. The extended cost-effectiveness analysis (ECEA) framework quantifies the broader value of universal vaccination starting with non-health benefits such as financial risk protection and equity. These dimensions better enable decision-makers to evaluate policy on the public finance of health programmes. Methods: The incidence, health service utilisation and household expenditure related to rotavirus gastroenteritis according to national income quintiles were obtained from local data sources. Multiple birth cohorts were distributed into income quintiles and followed from birth over the first five years of life in a multicohort, static model. Results: We found that the rich pay more out of pocket (OOP) than the poor, as the rich use more expensive private care. OOP payments among the poorest although small are high as a proportion of household income. Rotavirus vaccination results in substantial reduction in rotavirus episodes and expenditure and provides financial risk protection to all income groups. Poverty reduction benefits are concentrated amongst the poorest two income quintiles. Conclusion: We propose that universal vaccination complements health financing reforms in strengthening Universal Health Coverage (UHC). ECEA provides an important tool to understand the implications of vaccination for UHC, beyond traditional considerations of economic efficiency.

Routine Pediatric Enterovirus 71 Vaccination in China: a Cost-Effectiveness Analysis

Wu, J. T., Jit, M., Zheng, Y., Leung, K., Xing, W., Yang, J., Liao, Q., Cowling, B. J., Yang, B., Lau, E. H., Takahashi, S., Farrar, J. J., Grenfell, B. T., Leung, G. M., & Yu, H. (n.d.).

Publication year

2016

Journal title

PLoS Medicine

Volume

13

Issue

3
Abstract
Abstract
Background: China accounted for 87% (9.8 million/11.3 million) of all hand, foot, and mouth disease (HFMD) cases reported to WHO during 2010–2014. Enterovirus 71 (EV71) is responsible for most of the severe HFMD cases. Three EV71 vaccines recently demonstrated good efficacy in children aged 6–71 mo. Here we assessed the cost-effectiveness of routine pediatric EV71 vaccination in China. Methods and Findings: We characterized the economic and health burden of EV71-associated HFMD (EV71-HFMD) in China using (i) the national surveillance database, (ii) virological surveillance records from all provinces, and (iii) a caregiver survey on the household costs and health utility loss for 1,787 laboratory-confirmed pediatric cases. Using a static model parameterized with these data, we estimated the effective vaccine cost (EVC, defined as cost/efficacy or simply the cost of a 100% efficacious vaccine) below which routine pediatric vaccination would be considered cost-effective. We performed the base-case analysis from the societal perspective with a willingness-to-pay threshold of one times the gross domestic product per capita (GDPpc) and an annual discount rate of 3%. We performed uncertainty analysis by (i) accounting for the uncertainty in the risk of EV71-HFMD due to missing laboratory data in the national database, (ii) excluding productivity loss of parents and caregivers, (iii) increasing the willingness-to-pay threshold to three times GDPpc, (iv) increasing the discount rate to 6%, and (v) accounting for the proportion of EV71-HFMD cases not registered by national surveillance. In each of these scenarios, we performed probabilistic sensitivity analysis to account for parametric uncertainty in our estimates of the risk of EV71-HFMD and the expected costs and health utility loss due to EV71-HFMD. Routine pediatric EV71 vaccination would be cost-saving if the all-inclusive EVC is below US$10.6 (95% CI US$9.7–US$11.5) and would remain cost-effective if EVC is below US$17.9 (95% CI US$16.9–US$18.8) in the base case, but these ceilings could be up to 66% higher if all the test-negative cases with missing laboratory data are EV71-HFMD. The EVC ceiling is (i) 10%–14% lower if productivity loss of parents/caregivers is excluded, (ii) 58%–84% higher if the willingness-to-pay threshold is increased to three times GDPpc, (iii) 14%–19% lower if the discount rate is increased to 6%, and (iv) 36% (95% CI 23%–50%) higher if the proportion of EV71-HFMD registered by national surveillance is the same as that observed in the three EV71 vaccine phase III trials. The validity of our results relies on the following assumptions: (i) self-reported hospital charges are a good proxy for the opportunity cost of care, (ii) the cost and health utility loss estimates based on laboratory-confirmed EV71-HFMD cases are representative of all EV71-HFMD cases, and (iii) the long-term average risk of EV71-HFMD in the future is similar to that registered by national surveillance during 2010–2013. Conclusions: Compared to no vaccination, routine pediatric EV71 vaccination would be very cost-effective in China if the cost of immunization (including all logistical, procurement, and administration costs needed to confer 5 y of vaccine protection) is below US$12.0–US$18.3, depending on the choice of vaccine among the three candidates. Given that the annual number of births in China has been around 16 million in recent years, the annual costs for routine pediatric EV71 vaccination at this cost range should not exceed US$192–US$293 million. Our results can be used to determine the optimal vaccine when the prices of the three vaccines are known.

Seasonal influenza vaccination delivery through community pharmacists in England: Evaluation of the London pilot

Atkins, K., Van Hoek, A. J., Watson, C., Baguelin, M., Choga, L., Patel, A., Raj, T., Jit, M., & Griffiths, U. (n.d.).

Publication year

2016

Journal title

BMJ open

Volume

6

Issue

2
Abstract
Abstract
Objective: To evaluate the effectiveness and cost of the pan-London pharmacy initiative, a programme that allows administration of seasonal influenza vaccination to eligible patients at pharmacies. Design: We analysed 2013-2015 data on vaccination uptake in pharmacies via the Sonar reporting system, and the total vaccination uptake via 2011-2015 ImmForm general practitioner (GP) reporting system data. We conducted an online survey of London pharmacists who participate in the programme to assess time use data, vaccine choice, investment costs and opinions about the programme. We conducted an online survey of London GPs to assess vaccine choice of vaccine and opinions about the pharmacy vaccine delivery programme. Setting: All London boroughs. Participants: London-based GPs, and pharmacies that currently offer seasonal flu vaccination. Interventions: Not applicable. Main outcome measures: Comparison of annual vaccine uptake in London across risk groups from years before pharmacy vaccination introduction to after pharmacy vaccination introduction. Completeness of vaccine uptake reporting data. Cost to the National Health Service (NHS) of flu vaccine delivery at pharmacies with that at GPs. Cost to pharmacists of flu delivery. Opinions of pharmacists and GPs regarding the flu vaccine pharmacy initiative. Results: No significant change in the uptake of seasonal vaccination in any of the risk groups as a result of the pharmacy initiative. While on average a pharmacy-administered flu vaccine dose costs the NHS up to £2.35 less than a dose administered at a GP, a comparison of the 2 recording systems suggests there is substantial loss of data. Conclusions: Flu vaccine delivery through pharmacies shows potential for improving convenience for vaccine recipients. However, there is no evidence that vaccination uptake increases and the use of 2 separate recording systems leads to time-consuming data entry and missing vaccine record data.

The hidden health and economic burden of rotavirus gastroenteritis in Malaysia an estimation using multiple data sources

Loganathan, T., Ng, C. W., Lee, W. S., & Jit, M. (n.d.).

Publication year

2016

Journal title

Pediatric Infectious Disease Journal

Volume

35

Issue

6

Page(s)

601-606
Abstract
Abstract
Background: Rotavirus gastroenteritis (RVGE) results in substantial mortality and morbidity worldwide. However, an accurate estimation of the health and economic burden of RVGE in Malaysia covering public, private and home treatment is lacking. Methods: Data from multiple sources were used to estimate diarrheal mortality and morbidity according to health service utilization. The proportion of this burden attributable to rotavirus was estimated from a communitybased study and a meta-analysis we conducted of primary hospital-based studies. Rotavirus incidence was determined by multiplying acute gastroenteritis incidence with estimates of the proportion of gastroenteritis attributable to rotavirus. The economic burden of rotavirus disease was estimated from the health systems and societal perspective. Results: Annually, rotavirus results in 27 deaths, 31,000 hospitalizations, 41,000 outpatient visits and 145,000 episodes of home-treated gastroenteritis in Malaysia. We estimate an annual rotavirus incidence of 1 death per 100,000 children and 12 hospitalizations, 16 outpatient clinic visits and 57 home-treated episodes per 1000 children under-5 years. Annually, RVGE is estimated to cost US$ 34 million to the healthcare provider and US$ 50 million to society. Productivity loss contributes almost a third of costs to society. Publicly, privately and home-treated episodes consist of 52%, 27% and 21%, respectively, of the total societal costs. Conclusions: RVGE represents a considerable health and economic burden in Malaysia. Much of the burden lies in privately or home-treated episodes and is poorly captured in previous studies. This study provides vital information for future evaluation of cost-effectiveness, which are necessary for policy-making regarding universal vaccination.

The Long-Term Safety, Public Health Impact, and Cost-Effectiveness of Routine Vaccination with a Recombinant, Live-Attenuated Dengue Vaccine (Dengvaxia): A Model Comparison Study

Flasche, S., Jit, M., Rodríguez-Barraquer, I., Coudeville, L., Recker, M., Koelle, K., Milne, G., Hladish, T. J., Perkins, T. A., Cummings, D. A., Dorigatti, I., Laydon, D. J., España, G., Kelso, J., Longini, I., Lourenco, J., Pearson, C. A., Reiner, R. C., Mier-y-Terán-Romero, L., … Ferguson, N. (n.d.).

Publication year

2016

Journal title

PLoS Medicine

Volume

13

Issue

11
Abstract
Abstract
Background: Large Phase III trials across Asia and Latin America have recently demonstrated the efficacy of a recombinant, live-attenuated dengue vaccine (Dengvaxia) over the first 25 mo following vaccination. Subsequent data collected in the longer-term follow-up phase, however, have raised concerns about a potential increase in hospitalization risk of subsequent dengue infections, in particular among young, dengue-naïve vaccinees. We here report predictions from eight independent modelling groups on the long-term safety, public health impact, and cost-effectiveness of routine vaccination with Dengvaxia in a range of transmission settings, as characterised by seroprevalence levels among 9-y-olds (SP9). These predictions were conducted for the World Health Organization to inform their recommendations on optimal use of this vaccine. Methods and Findings: The models adopted, with small variations, a parsimonious vaccine mode of action that was able to reproduce quantitative features of the observed trial data. The adopted mode of action assumed that vaccination, similarly to natural infection, induces transient, heterologous protection and, further, establishes a long-lasting immunogenic memory, which determines disease severity of subsequent infections. The default vaccination policy considered was routine vaccination of 9-y-old children in a three-dose schedule at 80% coverage. The outcomes examined were the impact of vaccination on infections, symptomatic dengue, hospitalised dengue, deaths, and cost-effectiveness over a 30-y postvaccination period. Case definitions were chosen in accordance with the Phase III trials. All models predicted that in settings with moderate to high dengue endemicity (SP9 ≥ 50%), the default vaccination policy would reduce the burden of dengue disease for the population by 6%–25% (all simulations: –3%–34%) and in high-transmission settings (SP9 ≥ 70%) by 13%–25% (all simulations: 10%– 34%). These endemicity levels are representative of the participating sites in both Phase III trials. In contrast, in settings with low transmission intensity (SP9 ≤ 30%), the models predicted that vaccination could lead to a substantial increase in hospitalisation because of dengue. Modelling reduced vaccine coverage or the addition of catch-up campaigns showed that the impact of vaccination scaled approximately linearly with the number of people vaccinated. In assessing the optimal age of vaccination, we found that targeting older children could increase the net benefit of vaccination in settings with moderate transmission intensity (SP9 = 50%). Overall, vaccination was predicted to be potentially cost-effective in most endemic settings if priced competitively. The results are based on the assumption that the vaccine acts similarly to natural infection. This assumption is consistent with the available trial results but cannot be directly validated in the absence of additional data. Furthermore, uncertainties remain regarding the level of protection provided against disease versus infection and the rate at which vaccine-induced protection declines. Conclusions: Dengvaxia has the potential to reduce the burden of dengue disease in areas of moderate to high dengue endemicity. However, the potential risks of vaccination in areas with limited exposure to dengue as well as the local costs and benefits of routine vaccination are important considerations for the inclusion of Dengvaxia into existing immunisation programmes. These results were important inputs into WHO global policy for use of this licensed dengue vaccine.

The projected effectiveness of Clostridium difficile vaccination as part of an integrated infection control strategy

Van Kleef, E., Deeny, S. R., Jit, M., Cookson, B., Goldenberg, S. D., Edmunds, W. J., & Robotham, J. V. (n.d.).

Publication year

2016

Journal title

Vaccine

Volume

34

Issue

46

Page(s)

5562-5570
Abstract
Abstract
Background Early clinical trials of a Clostridium difficile toxoid vaccine show efficacy in preventing C. difficile infection (CDI). The optimal patient group to target for vaccination programmes remains unexplored. This study performed a model-based evaluation of the effectiveness of different CDI vaccination strategies, within the context of existing infection prevention and control strategies such as antimicrobial stewardship. Methods An individual-based transmission model of CDI in a high-risk hospital setting was developed. The model incorporated data on patient movements between the hospital, and catchment populations from the community and long-term care facilities (LTCF), using English national and local level data for model-parameterisation. We evaluated vaccination of: (1) discharged patients who had an CDI-occurrence in the ward; (2) LTCF-residents; (3) Planned elective surgical admissions and (4) All three strategies combined. Results Without vaccination, 10.9 [Interquartile range: 10.0–11.8] patients per 1000 ward admissions developed CDI, of which 31% were ward-acquired. Immunising all three patient groups resulted in a 43% [42–44], reduction of ward-onset CDI on average. Among the strategies restricting vaccination to one target group, vaccinating elective surgical patients proved most effective (35% [34–36] reduction), but least efficient, requiring 146 [133–162] courses to prevent one ICU-onset case. Immunising LTCF residents was most efficient, requiring just 13 [11–16] courses to prevent one case, but considering this only comprised a small group of our hospital population, it only reduced ICU-onset CDI by 9% [8–11]. Vaccination proved most efficient when ward-based transmission rates and antimicrobial consumption were high. Conclusions Strategy success depends on the interaction between hospital and catchment populations, and importantly, consideration of importations of CDI from outside the hospital which we found to substantially impact hospital dynamics. Vaccination may be most desirable in settings or patient groups where levels of broad-spectrum antimicrobial use are high and difficult to reduce.

A systematic review of the social and economic burden of influenza in low- and middle-income countries

De Francisco Shapovalova, N., Donadel, M., Jit, M., & Hutubessy, R. (n.d.).

Publication year

2015

Journal title

Vaccine

Volume

33

Issue

48

Page(s)

6537-6544
Abstract
Abstract
Objectives: The economic burden of seasonal influenza outbreaks as well as influenza pandemics in lower- and middle-income countries (LMIC) has yet to be specifically systematically reviewed. The aim of this systematic review is to assess the evidence of influenza economic burden assessment methods in LMIC and to quantify the economic consequences of influenza disease in these countries, including broader opportunity costs in terms of impaired social progress and economic development. Methods: We conducted an all language literature search across 5 key databases using an extensive list of key words for the time period 1950-2013. We included studies which explored direct costs (medical and non-medical), indirect costs (productivity losses), and broader economic impact in LMIC associated with different influenza outcomes such as confirmed seasonal influenza infection, influenza-like illnesses, and pandemic influenza. Results: We included 62 full-text studies in English, Spanish, Russian, Chinese languages, mostly from the countries of Latin American and the Caribbean and East Asia and Pacific with pertinent cost data found in 39 papers. Estimates for direct and indirect costs were the highest in Latin American and the Caribbean. Compared to high-income economies, direct costs in LMIC were lower and productivity losses higher. Evidence on broader impact of influenza included impact on the wider national economy, security dimension, medical insurance policy, legal frameworks, distributional impact, and investment flows. Conclusion: The economic burden of influenza in LMIC encompasses multiple dimensions such as direct costs to the health service and households, indirect costs due to productivity losses as well as broader detriments to the wider economy. Evidence from sub-Saharan Africa and in pregnant women remains very limited. Heterogeneity of methods used to estimate cost components makes data synthesis challenging. There is a strong need for standardizing research, data collection and evaluation methods for both direct and indirect cost components.

Building a new communication paradigm: Can we influence influenza perception?

Jit, M., McKenzie, D., Odugleh-Kolev, A., & Suisse, S. (n.d.).

Publication year

2015

Journal title

Vaccine

Volume

33

Issue

49

Page(s)

7044-7046

Burden of severe pneumonia, pneumococcal pneumonia and pneumonia deaths in Indian states: Modelling based estimates

Farooqui, H., Jit, M., Heymann, D. L., & Zodpey, S. (n.d.).

Publication year

2015

Journal title

PloS one

Volume

10

Issue

6
Abstract
Abstract
The burden of severe pneumonia in terms of morbidity and mortality is unknown in India especially at sub-national level. In this context, we aimed to estimate the number of severe pneumonia episodes, pneumococcal pneumonia episodes and pneumonia deaths in children younger than 5 years in 2010. We adapted and parameterized a mathematical model based on the epidemiological concept of potential impact fraction developed CHERG for this analysis. The key parameters that determine the distribution of severe pneumonia episode across Indian states were state-specific under-5 population, state-specific prevalence of selected definite pneumonia risk factors and meta-estimates of relative risks for each of these risk factors. We applied the incidence estimates and attributable fraction of risk factors to population estimates for 2010 of each Indian state. We then estimated the number of pneumococcal pneumonia cases by applying the vaccine probe methodology to an existing trial. We estimated mortality due to severe pneumonia and pneumococcal pneumonia by combining incidence estimates with case fatality ratios from multi-centric hospital-based studies. Our results suggest that in 2010, 3.6 million (3.3-3.9 million) episodes of severe pneumonia and 0.35 million (0.31-0.40 million) all cause pneumonia deaths occurred in children younger than 5 years in India. The states that merit special mention include Uttar Pradesh where 18.1% children reside but contribute 24% of pneumonia cases and 26% pneumonia deaths, Bihar (11.3% children, 16% cases, 22% deaths) Madhya Pradesh (6.6% children, 9% cases, 12% deaths), and Rajasthan (6.6% children, 8% cases, 11% deaths). Further, we estimated that 0.56 million (0.49-0.64 million) severe episodes of pneumococcal pneumonia and 105 thousand (92-119 thousand) pneumococcal deaths occurred in India. The top contributors to India's pneumococcal pneumonia burden were Uttar Pradesh, Bihar, Madhya Pradesh and Rajasthan in that order. Our results highlight the need to improve access to care and increase coverage and equity of pneumonia preventing vaccines in states with high pneumonia burden.

Calibration of complex models through bayesian evidence synthesis: A demonstration and tutorial

Jackson, C. H., Jit, M., Sharples, L. D., & De Angelis, D. (n.d.).

Publication year

2015

Journal title

Medical Decision Making

Volume

35

Issue

2

Page(s)

148-161
Abstract
Abstract
Decision-analytic models must often be informed using data that are only indirectly related to the main model parameters. The authors outline how to implement a Bayesian synthesis of diverse sources of evidence to calibrate the parameters of a complex model. A graphical model is built to represent how observed data are generated from statistical models with unknown parameters and how those parameters are related to quantities of interest for decision making. This forms the basis of an algorithm to estimate a posterior probability distribution, which represents the updated state of evidence for all unknowns given all data and prior beliefs. This process calibrates the quantities of interest against data and, at the same time, propagates all parameter uncertainties to the results used for decision making. To illustrate these methods, the authors demonstrate how a previously developed Markov model for the progression of human papillomavirus (HPV-16) infection was rebuilt in a Bayesian framework. Transition probabilities between states of disease severity are inferred indirectly from cross-sectional observations of prevalence of HPV-16 and HPV-16-related disease by age, cervical cancer incidence, and other published information. Previously, a discrete collection of plausible scenarios was identified but with no further indication of which of these are more plausible. Instead, the authors derive a Bayesian posterior distribution, in which scenarios are implicitly weighted according to how well they are supported by the data. In particular, we emphasize the appropriate choice of prior distributions and checking and comparison of fitted models.

Comparison of two dose and three dose human papillomavirus vaccine schedules: Cost effectiveness analysis based on transmission model

Jit, M., Brisson, M., Laprise, J. F., & Choi, Y. H. (n.d.).

Publication year

2015

Journal title

BMJ (Online)

Volume

350
Abstract
Abstract
Objective: To investigate the incremental cost effectiveness of two dose human papillomavirus vaccination and of additionally giving a third dose. Design: Cost effectiveness study based on a transmission dynamic model of human papillomavirus vaccination. Two dose schedules for bivalent or quadrivalent human papillomavirus vaccines were assumed to provide 10, 20, or 30 years' vaccine type protection and cross protection or lifelong vaccine type protection without cross protection. Three dose schedules were assumed to give lifelong vaccine type and cross protection. Setting: United Kingdom. Population: Males and females aged 12-74 years. Interventions: No, two, or three doses of human papillomavirus vaccine given routinely to 12 year old girls, with an initial catch-up campaign to 18 years. Main outcome measure: Costs (from the healthcare provider's perspective), health related utilities, and incremental cost effectiveness ratios. Results: Giving at least two doses of vaccine seems to be highly cost effective across the entire range of scenarios considered at the quadrivalent vaccine list price of £86.50 (€109.23; $136.00) per dose. If two doses give only 10 years' protection but adding a third dose extends this to lifetime protection, then the third dose also seems to be cost effective at £86.50 per dose (median incremental cost effectiveness ratio £17 000, interquartile range £11 700-£25 800). If two doses protect for more than 20 years, then the third dose will have to be priced substantially lower (median threshold price £31, interquartile range £28-£35) to be cost effective. Results are similar for a bivalent vaccine priced at £80.50 per dose and when the same scenarios are explored by parameterising a Canadian model (HPV-ADVISE) with economic data from the United Kingdom. Conclusions: Two dose human papillomavirus vaccine schedules are likely to be the most cost effective option provided protection lasts for at least 20 years. As the precise duration of two dose schedules may not be known for decades, cohorts given two doses should be closely monitored.

Controlling measles using supplemental immunization activities: A mathematical model to inform optimal policy

Verguet, S., Johri, M., Morris, S. K., Gauvreau, C. L., Jha, P., & Jit, M. (n.d.).

Publication year

2015

Journal title

Vaccine

Volume

33

Issue

10

Page(s)

1291-1296
Abstract
Abstract
Background: The Measles & Rubella Initiative, a broad consortium of global health agencies, has provided support to measles-burdened countries, focusing on sustaining high coverage of routine immunization of children and supplementing it with a second dose opportunity for measles vaccine through supplemental immunization activities (SIAs). We estimate optimal scheduling of SIAs in countries with the highest measles burden. Methods: We develop an age-stratified dynamic compartmental model of measles transmission. We explore the frequency of SIAs in order to achieve measles control in selected countries and two Indian states with high measles burden. Specifically, we compute the maximum allowable time period between two consecutive SIAs to achieve measles control. Results: Our analysis indicates that a single SIA will not control measles transmission in any of the countries with high measles burden. However, regular SIAs at high coverage levels are a viable strategy to prevent measles outbreaks. The periodicity of SIAs differs between countries and even within a single country, and is determined by population demographics and existing routine immunization coverage. Conclusions: Our analysis can guide country policymakers deciding on the optimal scheduling of SIA campaigns and the best combination of routine and SIA vaccination to control measles.

Contact

kmj7983@nyu.edu 708 Broadway New York, NY, 10003