Mark Jit
Mark Jit
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Chair and Professor of the Department of Global and Environmental Health
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Professional overview
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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.
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Education
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BSc, Mathematics, University College LondonPhD, Mathematics, University College LondonMPH, Public Health, King's College London
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Honors and awards
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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)
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Publications
Publications
7-valent pneumococcal conjugate vaccination in england and wales : Is it still beneficial despite high levels of serotype replacement?
AbstractChoi, Y. H., Jit, M., Gay, N., Andrews, N., Waight, P. A., Melegaro, A., George, R., & Miller, E. A. (n.d.).Publication year
2011Journal title
PloS oneVolume
6Issue
10AbstractBackground: The UK introduced the 7-valent pneumococcal conjugate vaccine (PCV7) into the national vaccination program in September 2006. Previous modelling assumed that the likely impact of PCV7 on invasive pneumococcal disease (IPD) would be similar to the US experience with PCV7. However, recent surveillance data show a more rapid replacement of PCV7 IPD cases by non-PCV7 IPD cases than was seen in the US. Methods and Findings: A previous model of pneumococcal vaccination was re-parameterised using data on vaccine coverage and IPD from England and Wales between 2006 and 2009. Disease incidence was adjusted for the increasing trend in reported IPD cases prior to vaccination. Using this data we estimated that individuals carrying PCV7 serotypes have much higher protection (96%;95% CI 72%-100%) against acquisition of NVT carriage than the 15% previously estimated from US data, which leads to greater replacement. However, even with this level of replacement, the annual number of IPD cases may be 560 (95% CI, -100 to 1230) lower ten years after vaccine introduction compared to what it may have been without vaccination. A particularly marked fall of 39% in children under 15 years by 2015/6 is predicted. Conclusion: Our model suggests that PCV7 vaccination could result in a decrease in overall invasive pneumococcal disease, particularly in children, even in an environment of rapid replacement with non-PCV7 serotypes within 5 years of vaccine introduction at high coverage.A bibliometric analysis of systematic reviews on vaccines and immunisation
AbstractFernandes, S., Jit, M., Bozzani, F., Griffiths, U. K., Scott, J. A., & Burchett, H. E. (n.d.).Publication year
2018Journal title
VaccineVolume
36Issue
17Page(s)
2254-2261AbstractIntroduction: SYSVAC is an online bibliographic database of systematic reviews and systematic review protocols on vaccines and immunisation compiled by the London School of Hygiene & Tropical Medicine and hosted by the World Health Organization (WHO) through their National Immunization Technical Advisory Groups (NITAG) resource centre (www.nitag-resource.org). Here the development of the database and a bibliometric review of its content is presented, describing trends in the publication of policy-relevant systematic reviews on vaccines and immunisation from 2008 to 2016. Materials and methods: Searches were conducted in seven scientific databases according to a standardized search protocol, initially in 2014 with the most recent update in January 2017. Abstracts and titles were screened according to specific inclusion criteria. All included publications were coded into relevant categories based on a standardized protocol and subsequently analysed to look at trends in time, topic, area of focus, population and geographic location. Results: After screening for inclusion criteria, 1285 systematic reviews were included in the database. While in 2008 there were only 34 systematic reviews on a vaccine-related topic, this increased to 322 in 2016. The most frequent pathogens/diseases studied were influenza, human papillomavirus and pneumococcus. There were several areas of duplication and overlap. Discussion: As more systematic reviews are published it becomes increasingly time-consuming for decision-makers to identify relevant information among the ever-increasing volume available. The risk of duplication also increases, particularly given the current lack of coordination of systematic reviews on vaccine-related questions, both in terms of their commissioning and their execution. The SYSVAC database offers an accessible catalogue of vaccine-relevant systematic reviews with, where possible access or a link to the full-text. Conclusions: SYSVAC provides a freely searchable platform to identify existing vaccine-policy-relevant systematic reviews. Systematic reviews will need to be assessed adequately for each specific question and quality.A brief history of economic evaluation for human papillomavirus vaccination policy
AbstractBeutels, P., & Jit, M. (n.d.).Publication year
2010Journal title
Sexual HealthVolume
7Issue
3Page(s)
352-358AbstractBackground: This commentary discusses key issues for health economic evaluation and modelling, applied to human papillomavirus (HPV) vaccine programs. Methods: We outline some of the specific features of HPV disease and vaccination, and associated policy questions in light of a literature search for economic evaluations on HPV vaccination. Results: We observe that some policy questions could not be reliably addressed by many of the 43 published economic evaluations we found. Despite this, policy making on universal HPV vaccination followed shortly after vaccine licensure in many developed countries, so the role economic evaluation played in informing these decisions (pre-dating 2008) seems to have been fairly limited. For more recent decisions, however, economic evaluation is likely to have been used more widely and more intensively. Conclusions: We expect future cost-effectiveness analyses to be more instrumental in policy making regarding vaccines covering more HPV types, therapeutic HPV vaccines, and novel diagnostic tests for biomarkers of HPV infection and disease integrated with cervical screening programs.A computational algorithm associated with patient progress modelling
AbstractJit, M., Gallivan, S., Utley, M., Jit, M., & Pagel, C. (n.d.).Publication year
2007Journal title
Computational Management ScienceVolume
4Issue
3Page(s)
283-299AbstractPatient progress modelling, which was first introduced to provide an alternative to traditional randomised control trials, has now been used in numerous contexts including evaluation of screening programmes and assessment of the public health impact of large scale developments such as waste disposal incinerators. The method uses stochastic compartmental models whose solutions may depend on solving large sets of matrix differential equations. Although specialist software packages are available for this purpose, we propose an alternative method for deriving the solution to such equations that is simple to implement.A cross-sectional analysis of meteorological factors and SARS-CoV-2 transmission in 409 cities across 26 countries
AbstractMCC Collaborative Research Network, A., CMMID COVID-19 Working Group, A., Sera, F., Armstrong, B., Abbott, S., Meakin, S., O’Reilly, K., von Borries, R., Schneider, R., Royé, D., Hashizume, M., Pascal, M., Tobias, A., Vicedo-Cabrera, A. M., Hu, W., Tong, S., Lavigne, E., Correa, P. M., Meng, X., … Jit, M. (n.d.).Publication year
2021Journal title
Nature communicationsVolume
12Issue
1AbstractThere is conflicting evidence on the influence of weather on COVID-19 transmission. Our aim is to estimate weather-dependent signatures in the early phase of the pandemic, while controlling for socio-economic factors and non-pharmaceutical interventions. We identify a modest non-linear association between mean temperature and the effective reproduction number (Re) in 409 cities in 26 countries, with a decrease of 0.087 (95% CI: 0.025; 0.148) for a 10 °C increase. Early interventions have a greater effect on Re with a decrease of 0.285 (95% CI 0.223; 0.347) for a 5th - 95th percentile increase in the government response index. The variation in the effective reproduction number explained by government interventions is 6 times greater than for mean temperature. We find little evidence of meteorological conditions having influenced the early stages of local epidemics and conclude that population behaviour and government interventions are more important drivers of transmission.A global agenda for older adult immunization in the COVID-19 era : A roadmap for action
AbstractPrivor-Dumm, L. A., Poland, G. A., Barratt, J., Durrheim, D. N., Deloria Knoll, M., Vasudevan, P., Jit, M., Bonvehí, P. E., & Bonanni, P. (n.d.).Publication year
2021Journal title
VaccineVolume
39Issue
37Page(s)
5240-5250AbstractGiven our global interconnectedness, the COVID-19 pandemic highlights the urgency of building a global system that can support both routine and pandemic/epidemic adult immunization. As such, a framework to recommend vaccines and build robust platforms to deliver them to protect the rapidly expanding demographic of older adults is needed. Adult immunization as a strategy has the broad potential to preserve and improve medical, social, and economic outcomes, including maintaining functional ability that benefits older adults, their families, communities, and countries. While we will soon have multiple vaccines against COVID-19, we must recognize that we already have a variety of vaccines against other pathogens that can keep adults healthier. They can prevent simultaneous co-infection with COVID-19, and may favorably impact- the outcome of a COVID-19 illness. Further, administering a vaccine against COVID-19 requires planning now to determine delivery strategies impacting how older adults will be immunized in a timely manner. A group of international experts with various backgrounds from health and aging disciplines met to discuss the evidence case for adult immunization and crucial knowledge gaps that must be filled in order to implement effective policies and programs for older adult immunization. This group, coming together as the International Council on Adult Immunization (ICAI), outlined a high-level roadmap to catalyze action, provide policy guidance, and envision a global adult immunization platform that can be adapted by countries to fit their local contexts. Further meetings centered around the value of adult immunization, particularly in the context of COVID-19. There was agreement that programs to deliver existing influenza, pneumococcal, herpes zoster vaccines, and future COVID-19 vaccines to over a billion older adults who are at substantially higher risk of death and disability due to vaccine-preventable diseases are more urgent than ever before. Here we present a proposed framework for delivering routine and pandemic vaccines. We call upon the global community and governments to prioritize action for integrating robust adult immunization programs into the public health agenda.A global assessment of the impact of school closure in reducing COVID-19 spread
AbstractWu, J. T., Mei, S., Luo, S., Leung, K., Liu, D., Lv, Q., Liu, J., Li, Y., Prem, K., Jit, M., Weng, J., Feng, T., Zheng, X., & Leung, G. M. (n.d.).Publication year
2022Journal title
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering SciencesVolume
380Issue
2214AbstractProlonged school closure has been adopted worldwide to control COVID-19. Indeed, UN Educational, Scientific and Cultural Organization figures show that two-thirds of an academic year was lost on average worldwide due to COVID-19 school closures. Such pre-emptive implementation was predicated on the premise that school children are a core group for COVID-19 transmission. Using surveillance data from the Chinese cities of Shenzhen and Anqing together, we inferred that compared with the elderly aged 60 and over, children aged 18 and under and adults aged 19-59 were 75% and 32% less susceptible to infection, respectively. Using transmission models parametrized with synthetic contact matrices for 177 jurisdictions around the world, we showed that the lower susceptibility of school children substantially limited the effectiveness of school closure in reducing COVID-19 transmissibility. Our results, together with recent findings that clinical severity of COVID-19 in children is lower, suggest that school closure may not be ideal as a sustained, primary intervention for controlling COVID-19. This article is part of the theme issue 'Data science approach to infectious disease surveillance'.A health technology assessment of COVID-19 vaccination for Nigerian decision-makers : Identifying stakeholders and pathways to support evidence uptake
AbstractUzochukwu, B. S., Okeke, C., Shuaib, F., Torres-Rueda, S., Vassall, A., Jit, M., Nonvignon, J., Uzochukwu, A. C., & Ruiz, F. (n.d.).Publication year
2024Journal title
Health Research Policy and SystemsVolume
22Issue
1AbstractBackground: Nigeria commenced rollout of vaccination for coronavirus disease 2019 (COVID-19) in March 2021 as part of the national public health response to the pandemic. Findings from appropriately contextualized cost–effectiveness analyses (CEA) as part of a wider process involving health technology assessment (HTA) approaches have been important in informing decision-making in this area. In this paper we outline the processes that were followed to identify COVID-19 vaccine stakeholders involved in the selection, approval, funding, procurement and rollout of vaccines in Nigeria, and describe the process routes we identified to support uptake of HTA-related information for evidence-informed policy in Nigeria. Methods: Our approach to engaging with policy-makers and other stakeholders as part of an HTA of COVID vaccination in Nigeria consisted of three steps, namely: (i) informal discussions with key stakeholders; (ii) stakeholder mapping, analysis and engagement; and (iii) communication and dissemination strategies for the HTA-relevant evidence produced. The analysis of the stakeholder mapping uses the power/interest grid framework. Results: The informal discussion with key stakeholders generated six initial policy questions. Further discussions with policy-makers yielded three suitable policy questions for analysis: which COVID-19 vaccines should be bought; what is the optimal mode of delivery of these vaccines; and what are the cost and cost–effectiveness of vaccinating people highlighted in Nigeria’s phase 2 vaccine rollout prioritized by the government, especially the inclusion of those aged between 18 and 49 years. The stakeholder mapping exercise highlighted the range of organizations and groups within Nigeria that could use the information from this HTA to guide decision-making. These stakeholders included both public/government, private and international organizations The dissemination plan developed included disseminating the full HTA results to key stakeholders; production of policy briefs; and presentation at different national and international conferences and peer-reviewed publications. Conclusions: HTA processes that involve stakeholder engagement will help ensure important policy questions are taken into account when designing any HTA including any underpinning evidence generation. Further guidance about stakeholder engagement throughout HTA is required, especially for those with low interest in vaccine procurement and use.A Randomized, Observer-Blinded Immunogenicity Trial of Cervarix® and Gardasil® Human Papillomavirus Vaccines in 12-15 Year Old Girls
AbstractDraper, E., Bissett, S. L., Howell-Jones, R., Waight, P., Soldan, K., Jit, M., Andrews, N., Miller, E. A., & Beddows, S. (n.d.).Publication year
2013Journal title
PloS oneVolume
8Issue
5AbstractBackground:The current generation of Human Papillomavirus (HPV) vaccines, Cervarix® and Gardasil®, exhibit a high degree of efficacy in clinical trials against the two high-risk (HR) genotypes represented in the vaccines (HPV16 and HPV18). High levels of neutralizing antibodies are elicited against the vaccine types, consistent with preclinical data showing that neutralizing antibodies can mediate type-specific protection in the absence of other immune effectors. The vaccines also confer protection against some closely related non-vaccine HR HPV types, although the vaccines appear to differ in their degree of cross-protection. The mechanism of vaccine-induced cross-protection is unknown. This study sought to compare the breadth and magnitudes of neutralizing antibodies against non-vaccine types elicited by both vaccines and establish whether such antibodies could be detected in the genital secretions of vaccinated individuals.Methods and Findings:Serum and genital samples were collected from 12-15 year old girls following vaccination with either Cervarix® (n = 96) or Gardasil® (n = 102) HPV vaccine. Serum-neutralizing antibody responses against non-vaccine HPV types were broader and of higher magnitude in the Cervarix®, compared to the Gardasil®, vaccinated individuals. Levels of neutralizing and binding antibodies in genital secretions were closely associated with those found in the serum (r = 0.869), with Cervarix® having a median 2.5 (inter-quartile range, 1.7-3.5) fold higher geometric mean HPV-specific IgG ratio in serum and genital samples than Gardasil® (p = 0.0047). There was a strong positive association between cross-neutralizing antibody seropositivity and available HPV vaccine trial efficacy data against non-vaccine types.Conclusions:These data demonstrate for the first time that cross-neutralizing antibodies can be detected at the genital site of infection and support the possibility that cross-neutralizing antibodies play a role in the cross-protection against HPV infection and disease that has been reported for the current HPV vaccines.Trial Registration:ClinicalTrials.gov NCT00956553.A review of the costs of delivering maternal immunisation during pregnancy
AbstractProcter, S. R., Salman, O., Pecenka, C., Gonçalves, B. P., Paul, P., Hutubessy, R., Lambach, P., Lawn, J. E., & Jit, M. (n.d.).Publication year
2020Journal title
VaccineVolume
38Issue
40Page(s)
6199-6204AbstractBackground: Routine maternal immunisation against influenza and pertussis are recommended by the WHO to protect mother and child, and new vaccines are under development. Introducing maternal vaccines into national programmes requires an understanding of vaccine delivery costs – particularly in low resource settings. Methods: We searched Medline, Embase, Econlit, and Global Health for studies reporting costs of delivering vaccination during pregnancy but excluded studies that did not separate the vaccine purchase price. Extracted costs were inflated and converted to 2018 US dollars. Results: Sixteen studies were included, of which two used primary data to estimate vaccine delivery costs. Costs per dose ranged from $0.55 to $0.64 in low-income countries, from $1.25 to $6.55 for middle-income countries, and from $5.76 to $39.87 in high-income countries. Conclusions: More research is needed on the costs of delivering maternal immunisation during pregnancy, and of integrating vaccine delivery into existing programmes of antenatal care especially in low and middle-income countries.A Scoping Review and Taxonomy of Epidemiological-Macroeconomic Models of COVID-19
AbstractBonnet, G., Pearson, C. A., Torres-Rueda, S., Ruiz, F., Lines, J., Jit, M., Vassall, A., & Sweeney, S. (n.d.).Publication year
2024Journal title
Value in HealthVolume
27Issue
1Page(s)
104-116AbstractObjectives: The COVID-19 pandemic placed significant strain on many health systems and economies. Mitigation policies decreased health impacts but had major macroeconomic impact. This article reviews models combining epidemiological and macroeconomic projections to enable policy makers to consider both macroeconomic and health objectives. Methods: A scoping review of epidemiological-macroeconomic models of COVID-19 was conducted, covering preprints, working articles, and journal publications. We assessed model methodologies, scope, and application to empirical data. Results: We found 80 articles modeling both the epidemiological and macroeconomic outcomes of COVID-19. Model scope is often limited to the impact of lockdown on health and total gross domestic product or aggregate consumption and to high-income countries. Just 14% of models assess disparities or poverty. Most models fall under 4 categories: compartmental-utility-maximization models, epidemiological models with stylized macroeconomic projections, epidemiological models linked to computable general equilibrium or input-output models, and epidemiological-economic agent-based models. We propose a taxonomy comparing these approaches to guide future model development. Conclusions: The epidemiological-macroeconomic models of COVID-19 identified have varying complexity and meet different modeling needs. Priorities for future modeling include increasing developing country applications, assessing disparities and poverty, and estimating of long-run impacts. This may require better integration between epidemiologists and economists.A Scoping Review of Investment Cases for Vaccines and Immunization Programs
AbstractSim, S. Y., Jit, M., Constenla, D., Peters, D. H., & Hutubessy, R. C. (n.d.).Publication year
2019Journal title
Value in HealthVolume
22Issue
8Page(s)
942-952AbstractBackground: Many investment cases have recently been published intending to show the value of new health investments, but without consistent methodological approaches. Objectives: To conduct a scoping review of existing investment cases (using vaccines and immunization programs as an example), identify common characteristics that define these investment cases, and examine their role within the broader context of the vaccine development and introduction. Methods: A systematic search was conducted from January 1980 to November 2017 to identify investment cases in the area of vaccines and immunization programs from gray literature and electronic bibliographic databases. Investment case outcomes, objectives, key variables, target audiences, and funding sources were extracted and analyzed according to their reporting frequency. Results: We found 24 investment cases, and most of them aim to provide information for decisions (12 cases) or advocate for a specific agenda (9 cases). Outcomes presented fell into 4 broad categories—burden of disease, cost of investment, impact of investment, and other considerations for implementation. Number of deaths averted (70%), incremental cost-effectiveness ratios (67%), and reduction in health and socioeconomic inequalities (54%) were the most frequently reported outcome measures for impact of investment. Health system capacity (79%) and vaccine financing landscape (75%) were the most common considerations for implementation. A sizable proportion (41.4%) of investment cases did not reveal their funding sources. Conclusions: This review describes information that is critical to decision making about resource mobilization and allocation concerning vaccines. Global efforts to harmonize investment cases more broadly will increase transparency and comparability.A stochastic model to evaluate options for antenatal genetic screening
AbstractGallivan, S., Jit, M., & Utley, M. (n.d.).Publication year
2006Journal title
Health Care Management ScienceVolume
9Issue
2Page(s)
111-124AbstractHaemoglobinopathies are a group of genetic disorders which are particularly prevalent among certain risk groups such as ethnic groups. Antenatal screening of potential haemoglobinopathy carriers allows early diagnosis for affected fetuses, leading to therapeutic intervention or termination. However, it has drawbacks such as screening costs and possible miscarriage as a result of fetal testing. This paper describes a model that allows the outcomes of a screening programme to be estimated for different risk groups. The model has been implemented as a computer package that can be used to inform decisions made by health care planners.A systematic review of the social and economic burden of influenza in low- and middle-income countries
Abstractde Francisco Shapovalova, N., Donadel, M., Jit, M., & Hutubessy, R. (n.d.).Publication year
2015Journal title
VaccineVolume
33Issue
48Page(s)
6537-6544AbstractObjectives: 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.A systematised review and evidence synthesis on the broader societal impact of vaccines against Salmonella
AbstractDemirtas, E. D., Barnard, R., Lee, J., & Jit, M. (n.d.).Publication year
2025Journal title
npj VaccinesVolume
10Issue
1AbstractVaccines against Salmonella Typhi are available, while vaccines against invasive non-typhoidal Salmonella are in development. Investments in vaccine development and introduction need to be informed by a full value of vaccines assessment, including consideration of broader societal impacts of salmonellae disease. We reviewed literature on these broader impacts in low- and middle-income countries to inform a conceptual framework. We found 16 studies relevant to Salmonella, but only one study on non-typhoidal Salmonella. Despite variations in study design, methodology, and study quality, salmonellae infections were largely associated with negative broader societal impacts, including detriments in childhood physical development (very weak association), childhood educational development (strong to very strong association), household security (moderate association), public health spending (moderate association), and national income (moderate to strong association). Study quality was low for all impacts except childhood physical development. There were no studies measuring economic impact of antimicrobial resistance, changes in household behaviour or health inequalities.A vaccine chatbot intervention for parents to improve HPV vaccination uptake among middle school girls : a cluster randomized trial
AbstractHou, Z., Wu, Z., Qu, Z., Gong, L., Peng, H., Jit, M., Larson, H. J., Wu, J. T., & Lin, L. (n.d.).Publication year
2025Journal title
Nature MedicineAbstractConversational artificial intelligence, in the form of chatbots powered by large language models, offers a new approach to facilitating human-like interactions, yet its efficacy in enhancing vaccination uptake remains under-investigated. This study assesses the effectiveness of a vaccine chatbot in improving human papillomavirus (HPV) vaccination among female middle school students aged 12–15 years across diverse socioeconomic settings in China, where HPV vaccination is primarily paid out-of-pocket. A school-based cluster randomized trial was conducted from 18 January to 31 May 2024. The study included 2,671 parents from 180 middle school classes stratified by socioeconomic setting, school and grade level in Shanghai megacity, and urban and rural regions of Anhui Province. Participants were randomly assigned to either the intervention group (90 classes, 1,294 parents), which engaged with the chatbot for two weeks, or the control group (90 classes, 1,377 parents), which received usual care. The primary outcome was the receipt or scheduled appointment of the HPV vaccine for participants’ daughters. In intention-to-treat analyses, 7.1% of the intervention group met this outcome versus 1.8% of the control group (P < 0.001) over a two-week intervention period. In addition, there was a statistically significant increase in HPV vaccination-specific consultations with health professionals (49.1% versus 17.6%, P < 0.001), along with enhanced vaccine literacy (P < 0.001) and rumor discernment (P < 0.001) among participants using the chatbot. These findings indicate that the chatbot effectively increased vaccination and improved parental vaccine literacy, although further research is necessary to scale and sustain these gains. Clinical trial registration: NCT06227689.Acceptability and uptake of female adolescent HPV vaccination in Hong Kong : A survey of mothers and adolescents
AbstractChoi, H. C., Leung, G. M., Woo, P. P., Jit, M., & Wu, J. T. (n.d.).Publication year
2013Journal title
VaccineVolume
32Issue
1Page(s)
78-84AbstractBackground: Organized population-based HPV vaccination programs can be effective in reducing the burden of cervical cancer, especially in the absence of a comprehensive cervical screening program (e.g. Hong Kong). Assessment of vaccine acceptability is important when evaluating the feasibility and cost-effectiveness of such vaccination programs. Methods: To provide a more representative and updated assessment on the acceptability of female adolescent HPV vaccination in Hong Kong, we conducted surveys in 2008 among 1022 mothers with daughters aged ≤18 years through random digit-dialing telephone interviewing and 2167 schoolgirls aged 11-18 years using two-stage stratified cluster sampling. We conducted the maternal survey again in 2012 with an independent group of 1005 mothers. Results: In 2008, 2.4% (95% confidence interval [CI] = 1.8-3.2%) of the recruited schoolgirls reported having received HPV vaccination. In 2012, the mothers reported that 9.1% (7.0-11.6%) of their daughters who were in the same age range (11-18 years) as the schoolgirls had been vaccinated (p < 0.01). Regarding acceptability, 27.5% (24.8-30.4%) and 37.6% (34.5-40.8%) of the mothers were willing to have their daughters vaccinated at market price in 2008 and 2012 (p < 0.01), respectively. 27.1% (25.2-29.1%) of the schoolgirls were willing to receive HPV vaccination at market price in 2008. The willingness to pay for full-course vaccination among mothers had a median of US$128/HK$1000 (50% central range = US$64-192/HK$500-1500), i.e. substantially lower than the current market price. Conclusions: The gap between acceptability and actual uptake of HPV vaccination among adolescent girls suggested that coverage is likely to be low without an organized HPV vaccination program, although the difference might be partially attributed to the possibility that at the time of the interview female adolescents who were willing to be vaccinated had not yet taken action. Policymakers should devise tailored, targeted and efficient vaccination strategies to achieve universal coverage for an effectively organized HPV vaccination program.Access and Unmet Needs of Orphan Drugs in 194 Countries and 6 Areas : A Global Policy Review With Content Analysis
AbstractChan, A. Y., Chan, V. K., Olsson, S., Fan, M., Jit, M., Gong, M., Zhang, S., Ge, M., Pathadka, S., Chung, C. C., Chung, B. H., Chui, C. S., Chan, E. W., Wong, G. H., Lum, T. Y., Wong, I. C., Ip, P., & Li, X. (n.d.).Publication year
2020Journal title
Value in HealthVolume
23Issue
12Page(s)
1580-1591AbstractObjectives: Three hundred million people living with rare diseases worldwide are disproportionately deprived of in-time diagnosis and treatment compared with other patients. This review provides an overview of global policies that optimize development, licensing, pricing, and reimbursement of orphan drugs. Methods: Pharmaceutical legislation and policies related to access and regulation of orphan drugs were examined from 194 World Health Organization member countries and 6 areas. Orphan drug policies (ODPs) were identified through internet search, emails to national pharmacovigilance centers, and systematic academic literature search. Texts from selected publications were extracted for content analysis. Results: One hundred seventy-two drug regulation documents and 77 academic publications from 162 countries/areas were included. Ninety-two of 200 countries/areas (46.0%) had documentation on ODPs. Thirty-four subthemes from content analysis were categorized into 6 policy themes, namely, orphan drug designation, marketing authorization, safety and efficacy requirements, price regulation, incentives that encourage market availability, and incentives that encourage research and development. Countries/areas with ODPs were statistically wealthier (gross national income per capita = $10 875 vs $3950, PAccounting for methodological, structural, and parameter uncertainty in decision-analytic models : A practical guide
AbstractBilcke, J., Beutels, P., Brisson, M., & Jit, M. (n.d.).Publication year
2011Journal title
Medical Decision MakingVolume
31Issue
4Page(s)
675-692AbstractAccounting for uncertainty is now a standard part of decision-analytic modeling and is recommended by many health technology agencies and published guidelines. However, the scope of such analyses is often limited, even though techniques have been developed for presenting the effects of methodological, structural, and parameter uncertainty on model results. To help bring these techniques into mainstream use, the authors present a step-by-step guide that offers an integrated approach to account for different kinds of uncertainty in the same model, along with a checklist for assessing the way in which uncertainty has been incorporated. The guide also addresses special situations such as when a source of uncertainty is difficult to parameterize, resources are limited for an ideal exploration of uncertainty, or evidence to inform the model is not available or not reliable. Methods for identifying the sources of uncertainty that influence results most are also described. Besides guiding analysts, the guide and checklist may be useful to decision makers who need to assess how well uncertainty has been accounted for in a decision-analytic model before using the results to make a decision.Adding interventions to mass measles vaccinations in India
AbstractJohri, M., Verguet, S., Morris, S. K., Sharma, J. K., Ram, U., Gauvreau, C., Jones, E., Jha, P., & Jit, M. (n.d.).Publication year
2016Journal title
Bulletin of the World Health OrganizationVolume
94Issue
10Page(s)
718-727AbstractObjective 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.Adding new childhood vaccines to China's National Immunization Program : evidence, benefits, and priorities
AbstractZhang, H., Lai, X., Patenaude, B. N., Jit, M., & Fang, H. (n.d.).Publication year
2023Journal title
The Lancet Public HealthVolume
8Issue
12Page(s)
e1016-e1024AbstractChina's National Immunization Program has made remarkable achievements but does not include several important childhood vaccines that are readily available in the private market, such as pneumococcal conjugate vaccine (PCV), rotavirus vaccine, Haemophilus influenzae serotype b (Hib) vaccine, and varicella vaccine. We reviewed the literature to assess these four non-National Immunization Program vaccines in terms of their disease burdens, coverage, inequalities, and cost-effectiveness in China and aimed to recommend priorities for introducing them to the National Immunization Program. Based on our calculations using the available evidence, incorporating these vaccines into China's National Immunization Program in 2019 could have averted 11 761 deaths among children younger than 5 years, accounting for 10·29% of the total deaths in children younger than 5 years and reducing the mortality rate from 7·8 per 1000 to 7·0 per 1000. The review showed that 13-valent PCV (PCV13) had the lowest and most inequitable coverage but could prevent the highest number of deaths. In a budgetary analysis for the cohort of newborns in 2023, we estimated that the projected aggregate government costs were US$1954·92 million for PCV13, $1273·13 million for pentavalent rotavirus vaccine, $415·30 million for Hib vaccine, and $221·64 million for varicella vaccine. Our overall multicriteria decision analysis suggested the following priority order for introducing these four non-programme vaccines to the National Immunization Program to benefit the Chinese population: PCV13, rotavirus vaccine, Hib vaccine, and varicella vaccine.Adjusting for Inflation and Currency Changes Within Health Economic Studies
AbstractTurner, H. C., Lauer, J. A., Tran, B. X., Teerawattananon, Y., & Jit, M. (n.d.).Publication year
2019Journal title
Value in HealthVolume
22Issue
9Page(s)
1026-1032AbstractObjectives: Within health economic studies, it is often necessary to adjust costs obtained from different time periods for inflation. Nevertheless, many studies do not report the methods used for this in sufficient detail. In this article, we outline the principal methods used to adjust for inflation, with a focus on studies relating to healthcare interventions in low- and middle-income countries. We also discuss issues relating to converting local currencies to international dollars and US$ and adjusting cost data collected from other countries or previous studies. Methods: We outlined the 3 main methods used to adjust for inflation for studies in these settings: exchanging the local currency to US$ or international dollars and then inflating using US inflation rates (method 1); inflating the local currency using local inflation rates and then exchanging to US$ or international dollars (method 2); splitting the costs into tradable and nontradable resources and using method 1 on the tradable resources and method 2 on the nontradable resources (method 3). Results: In a hypothetical example of adjusting a cost of US$100 incurred in Vietnam from 2006 to 2016 prices, the adjusted cost from the 3 methods were US$116.84, US$172.09, and US$161.04, respectively. Conclusions: The different methods for adjusting for inflation can yield substantially different results. We make recommendations regarding the most appropriate method for various scenarios. Moving forward, it is vital that studies report the methodology they use to adjust for inflation more transparently.Age-dependent effects in the transmission and control of COVID-19 epidemics
AbstractCMMID COVID-19 Working Group, A., Davies, N. G., Klepac, P., Liu, Y., Prem, K., Jit, M., Pearson, C. A., Quilty, B. J., Kucharski, A. J., Gibbs, H., Clifford, S., Gimma, A., van Zandvoort, K., Munday, J. D., Diamond, C., Edmunds, W. J., Houben, R. M., Hellewell, J., Russell, T. W., … Eggo, R. M. (n.d.).Publication year
2020Journal title
Nature MedicineVolume
26Issue
8Page(s)
1205-1211AbstractThe COVID-19 pandemic has shown a markedly low proportion of cases among children1–4. Age disparities in observed cases could be explained by children having lower susceptibility to infection, lower propensity to show clinical symptoms or both. We evaluate these possibilities by fitting an age-structured mathematical model to epidemic data from China, Italy, Japan, Singapore, Canada and South Korea. We estimate that susceptibility to infection in individuals under 20 years of age is approximately half that of adults aged over 20 years, and that clinical symptoms manifest in 21% (95% credible interval: 12–31%) of infections in 10- to 19-year-olds, rising to 69% (57–82%) of infections in people aged over 70 years. Accordingly, we find that interventions aimed at children might have a relatively small impact on reducing SARS-CoV-2 transmission, particularly if the transmissibility of subclinical infections is low. Our age-specific clinical fraction and susceptibility estimates have implications for the expected global burden of COVID-19, as a result of demographic differences across settings. In countries with younger population structures—such as many low-income countries—the expected per capita incidence of clinical cases would be lower than in countries with older population structures, although it is likely that comorbidities in low-income countries will also influence disease severity. Without effective control measures, regions with relatively older populations could see disproportionally more cases of COVID-19, particularly in the later stages of an unmitigated epidemic.An Application of an Initial Full Value of Vaccine Assessment Methodology to Measles-Rubella MAPs for Use in Low- and Middle-Income Countries
AbstractKo, M., Frivold, C., Mvundura, M., Soble, A., Gregory, C., Christiansen, H., Hasso-Agopsowicz, M., Fu, H., Jit, M., Hsu, S., Mistilis, J. J., Scarna, T., Earle, K., Menozzi-Arnaud, M., Giersing, B., Jarrahian, C., Yakubu, A., Malvolti, S., & Amorij, J. P. (n.d.).Publication year
2024Journal title
VaccinesVolume
12Issue
9AbstractMeasles and rubella micro-array patches (MR-MAPs) are a promising innovation to address limitations of the current needle and syringe (N&S) presentation due to their single-dose presentation, ease of use, and improved thermostability. To direct and accelerate further research and interventions, an initial full value vaccine assessment (iFVVA) was initiated prior to MR-MAPs entering phase I trials to quantify their value and identify key data gaps and challenges. The iFVVA utilized a mixed-methods approach with rapid assessment of literature, stakeholder interviews and surveys, and quantitative data analyses to (i) assess global need for improved MR vaccines and how MR-MAPs could address MR problem statements; (ii) estimate costs and benefits of MR-MAPs; (iii) identify the best pathway from development to delivery; and (iv) identify outstanding areas of need where stakeholder intervention can be helpful. These analyses found that if MR-MAPs are broadly deployed, they can potentially reach an additional 80 million children compared to the N&S presentation between 2030–2040. MR-MAPs can avert up to 37 million measles cases, 400,000 measles deaths, and 26 million disability-adjusted life years (DALYs). MR-MAPs with the most optimal product characteristics of low price, controlled temperature chain (CTC) properties, and small cold chain volumes were shown to be cost saving for routine immunization (RI) in low- and middle-income countries (LMICs) compared to N&S. Uncertainties about price and future vaccine coverage impact the potential cost-effectiveness of introducing MR-MAPs in LMICs, indicating that it could be cost-effective in 16–81% of LMICs. Furthermore, this iFVVA highlighted the importance of upfront donor investment in manufacturing set-up and clinical studies and the critical influence of an appropriate price to ensure country and manufacturer financial sustainability. To ensure that MR-MAPs achieve the greatest public health benefit, MAP developers, vaccine manufacturers, donors, financiers, and policy- and decision-makers will need close collaboration and open communications.An integrated approach to evaluating alternative risk prediction strategies : A case study comparing alternative approaches for preventing invasive fungal disease
AbstractJit, M., Sadique, Z., Grieve, R., Harrison, D. A., Jit, M., Allen, E., & Rowan, K. M. (n.d.).Publication year
2013Journal title
Value in HealthVolume
16Issue
8Page(s)
1111-1122AbstractObjectives This article proposes an integrated approach to the development, validation, and evaluation of new risk prediction models illustrated with the Fungal Infection Risk Evaluation study, which developed risk models to identify non-neutropenic, critically ill adult patients at high risk of invasive fungal disease (IFD). Methods Our decision-analytical model compared alternative strategies for preventing IFD at up to three clinical decision time points (critical care admission, after 24 hours, and end of day 3), followed with antifungal prophylaxis for those judged "high" risk versus "no formal risk assessment." We developed prognostic models to predict the risk of IFD before critical care unit discharge, with data from 35,455 admissions to 70 UK adult, critical care units, and validated the models externally. The decision model was populated with positive predictive values and negative predictive values from the best-fitting risk models. We projected lifetime cost-effectiveness and expected value of partial perfect information for groups of parameters. Results The risk prediction models performed well in internal and external validation. Risk assessment and prophylaxis at the end of day 3 was the most cost-effective strategy at the 2% and 1% risk threshold. Risk assessment at each time point was the most cost-effective strategy at a 0.5% risk threshold. Expected values of partial perfect information were high for positive predictive values or negative predictive values (£11 million-£13 million) and quality-adjusted life-years (£11 million). Conclusions It is cost-effective to formally assess the risk of IFD for non-neutropenic, critically ill adult patients. This integrated approach to developing and evaluating risk models is useful for informing clinical practice and future research investment.