Mark Jit

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

Effectiveness of isolation, testing, contact tracing, and physical distancing on reducing transmission of SARS-CoV-2 in different settings : a mathematical modelling study

CMMID COVID-19 Working Group, A., Kucharski, A. J., Klepac, P., Conlan, A. J., Kissler, S. M., Tang, M. L., Fry, H., Gog, J. R., Edmunds, W. J., Emery, J. C., Medley, G., Munday, J. D., Russell, T. W., Leclerc, Q. J., Diamond, C., Procter, S. R., Gimma, A., Sun, F. Y., Gibbs, H. P., … Davies, N. G. (n.d.).

Publication year

2020

Journal title

The Lancet Infectious Diseases

Volume

20

Issue

10

Page(s)

1151-1160

10.1016/S1473-3099(20)30457-6

Abstract

Abstract

Background: The isolation of symptomatic cases and tracing of contacts has been used as an early COVID-19 containment measure in many countries, with additional physical distancing measures also introduced as outbreaks have grown. To maintain control of infection while also reducing disruption to populations, there is a need to understand what combination of measures—including novel digital tracing approaches and less intensive physical distancing—might be required to reduce transmission. We aimed to estimate the reduction in transmission under different control measures across settings and how many contacts would be quarantined per day in different strategies for a given level of symptomatic case incidence. Methods: For this mathematical modelling study, we used a model of individual-level transmission stratified by setting (household, work, school, or other) based on BBC Pandemic data from 40 162 UK participants. We simulated the effect of a range of different testing, isolation, tracing, and physical distancing scenarios. Under optimistic but plausible assumptions, we estimated reduction in the effective reproduction number and the number of contacts that would be newly quarantined each day under different strategies. Results: We estimated that combined isolation and tracing strategies would reduce transmission more than mass testing or self-isolation alone: mean transmission reduction of 2% for mass random testing of 5% of the population each week, 29% for self-isolation alone of symptomatic cases within the household, 35% for self-isolation alone outside the household, 37% for self-isolation plus household quarantine, 64% for self-isolation and household quarantine with the addition of manual contact tracing of all contacts, 57% with the addition of manual tracing of acquaintances only, and 47% with the addition of app-based tracing only. If limits were placed on gatherings outside of home, school, or work, then manual contact tracing of acquaintances alone could have an effect on transmission reduction similar to that of detailed contact tracing. In a scenario where 1000 new symptomatic cases that met the definition to trigger contact tracing occurred per day, we estimated that, in most contact tracing strategies, 15 000–41 000 contacts would be newly quarantined each day. Interpretation: Consistent with previous modelling studies and country-specific COVID-19 responses to date, our analysis estimated that a high proportion of cases would need to self-isolate and a high proportion of their contacts to be successfully traced to ensure an effective reproduction number lower than 1 in the absence of other measures. If combined with moderate physical distancing measures, self-isolation and contact tracing would be more likely to achieve control of severe acute respiratory syndrome coronavirus 2 transmission. Funding: Wellcome Trust, UK Engineering and Physical Sciences Research Council, European Commission, Royal Society, Medical Research Council.

Effects of non-pharmaceutical interventions on COVID-19 cases, deaths, and demand for hospital services in the UK : a modelling study

Centre for the Mathematical Modelling of Infectious Diseases COVID-19 working group, A., Davies, N. G., Kucharski, A. J., Eggo, R. M., Gimma, A., Edmunds, W. J., Jombart, T., O'Reilly, K., Endo, A., Hellewell, J., Nightingale, E. S., Quilty, B. J., Jarvis, C. I., Russell, T. W., Klepac, P., Bosse, N. I., Funk, S., Abbott, S., Medley, G. F., … Liu, Y. (n.d.).

Publication year

2020

Journal title

The Lancet Public Health

Volume

5

Issue

7

Page(s)

e375-e385

10.1016/S2468-2667(20)30133-X

Abstract

Abstract

Background: Non-pharmaceutical interventions have been implemented to reduce transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the UK. Projecting the size of an unmitigated epidemic and the potential effect of different control measures has been crucial to support evidence-based policy making during the early stages of the epidemic. This study assesses the potential impact of different control measures for mitigating the burden of COVID-19 in the UK. Methods: We used a stochastic age-structured transmission model to explore a range of intervention scenarios, tracking 66·4 million people aggregated to 186 county-level administrative units in England, Wales, Scotland, and Northern Ireland. The four base interventions modelled were school closures, physical distancing, shielding of people aged 70 years or older, and self-isolation of symptomatic cases. We also modelled the combination of these interventions, as well as a programme of intensive interventions with phased lockdown-type restrictions that substantially limited contacts outside of the home for repeated periods. We simulated different triggers for the introduction of interventions, and estimated the impact of varying adherence to interventions across counties. For each scenario, we projected estimated new cases over time, patients requiring inpatient and critical care (ie, admission to the intensive care units [ICU]) treatment, and deaths, and compared the effect of each intervention on the basic reproduction number, R0. Findings: We projected a median unmitigated burden of 23 million (95% prediction interval 13–30) clinical cases and 350 000 deaths (170 000–480 000) due to COVID-19 in the UK by December, 2021. We found that the four base interventions were each likely to decrease R0, but not sufficiently to prevent ICU demand from exceeding health service capacity. The combined intervention was more effective at reducing R0, but only lockdown periods were sufficient to bring R0 near or below 1; the most stringent lockdown scenario resulted in a projected 120 000 cases (46 000–700 000) and 50 000 deaths (9300–160 000). Intensive interventions with lockdown periods would need to be in place for a large proportion of the coming year to prevent health-care demand exceeding availability. Interpretation: The characteristics of SARS-CoV-2 mean that extreme measures are probably required to bring the epidemic under control and to prevent very large numbers of deaths and an excess of demand on hospital beds, especially those in ICUs. Funding: Medical Research Council.

Effects of sequential vs single pneumococcal vaccination on cardiovascular diseases among older adults : a population-based cohort study

Tong, X., Gao, L., Wong, I. C., Chan, V. K., Wong, A. Y., Mak, J. C., Yuen, J. K., Jit, M., Hung, I. F., Yiu, K. H., & Li, X. (n.d.).

Publication year

2024

Journal title

International Journal of Epidemiology

Volume

53

Issue

1

10.1093/ije/dyae005

Abstract

Abstract

Background: Recommendations around the use of 23-valent pneumococcal polysaccharide vaccine (PPSV23) and 13-valent pneumococcal conjugate vaccine (PCV13) seldom focus on potential benefits of vaccine on comorbidities. We aimed to investigate whether sequential vaccination with PCV13 and PPSV23 among older adults would provide protection against cardiovascular diseases (CVD) compared with using a single pneumococcal vaccine. Methods: We conducted a Hong Kong-wide retrospective cohort study between 2012 and 2020. Adults aged ≥65 years were identified as receiving either a single or sequential dual vaccination and followed up until the earliest CVD occurrence, death or study end. To minimize confounding, we matched each person receiving a single vaccination to a person receiving sequential vaccination according to their propensity scores. We estimated the hazard ratio (HR) of CVD risk using Cox regression and applied structural equation modelling to test whether the effect of sequential dual vaccination on CVD was mediated via the reduction in pneumonia. Results: After matching, 69 390 people remained in each group and the median (interquartile range) follow-up time was 1.89 (1.55) years. Compared with those receiving a single vaccine, those receiving sequential dual vaccination had a lower risk of CVD [HR (95% CI): 0.75 (0.71, 0.80), P < 0.001]. Post-hoc mediation analysis showed strong evidence that the decreased CVD risk was mediated by the reduction in all-cause pneumonia. Conclusions: Sequential dual pneumococcal vaccination was associated with lower risk of CVD compared with single-dose PCV13 or PPSV23 in older adults. Such additional CVD benefits should be considered when making decisions about pneumococcal vaccination.

Effects of updated demography, disability weights, and cervical cancer burden on estimates of human papillomavirus vaccination impact at the global, regional, and national levels : a PRIME modelling study

Abbas, K. M., van Zandvoort, K., Brisson, M., & Jit, M. (n.d.).

Publication year

2020

Journal title

The Lancet Global Health

Volume

8

Issue

4

Page(s)

e536-e544

10.1016/S2214-109X(20)30022-X

Abstract

Abstract

Background: The Papillomavirus Rapid Interface for Modelling and Economics (PRIME) has been used around the world to assess the health impact and cost-effectiveness of human papillomavirus (HPV) vaccination in girls. We updated PRIME with new data and methods for demography, disability weights, and cervical cancer burden, and generated revised estimates of the health impact of HPV vaccination at the global, regional, and national levels for 177 countries. Methods: PRIME was updated with population demography of the UN World Population Prospects (UNWPP) 2019 revision, disability weights of the Global Burden of Disease (GBD) 2017 study, and cervical cancer burden from the Global Cancer Incidence, Mortality and Prevalence (GLOBOCAN) 2018 database. We estimated the lifetime health benefits for bivalent or quadrivalent and nonavalent vaccination of 9-year-old and 12-year-old girls at 90% coverage during 2020–29 in 177 countries. Health impact was presented in terms of cervical cancer cases, deaths, or disability-adjusted life-years (DALYs) averted per 1000 vaccinated girls in comparison with the counterfactual scenario of no vaccination, and the number of girls needed to be vaccinated to prevent a single case, death, or DALY. Findings: In estimating the health impact of HPV vaccination of 9-year-old girls, the combined updates to demography, disability weights, cervical cancer burden estimates resulted in a 26% increase in the estimated number of cases averted, a 51% increase in deaths averted, and a 72% increase in DALYs averted per 1000 vaccinated girls for both the bivalent or quadrivalent and nonavalent vaccines, compared with previous estimates. With the updated model, the bivalent or quadrivalent HPV vaccine was estimated to avert 15 cases, 12 deaths, and 243 DALYs per 1000 vaccinated girls, and the nonavalent HPV vaccine was estimated to avert 19 cases, 14 deaths, and 306 DALYs per 1000 vaccinated girls. The health benefits of vaccination of 12-year-old girls were estimated to be similar but slightly decreased in comparison with vaccination of 9-year-old girls. Interpretation: HPV vaccination provides greater health benefits and is more cost-effective than was previously estimated. The demography update, which incorporates population aging, has the largest effect on the health impact estimates. The WHO African region is expected to gain the greatest health benefits and should be prioritised for HPV vaccination. Funding: Gavi, the Vaccine Alliance; Bill & Melinda Gates Foundation.

Efficacy and effectiveness of seasonal and pandemic A (H1N1) 2009 influenza vaccines in low and middle income countries : A systematic review and meta-analysis

Breteler, J. K., Tam, J. S., Jit, M., Ket, J. C., & De Boer, M. R. (n.d.).

Publication year

2013

Journal title

Vaccine

Volume

31

Issue

45

Page(s)

5168-5177

10.1016/j.vaccine.2013.08.056

Abstract

Abstract

Purpose: Influenza vaccines have been recommended for populations at risk for severe infection in low and middle income countries (LMICs) although knowledge of the evidence-base for their effectiveness and efficacy is limited in these countries. The aim of this systematic review is to provide an overview of the evidence-base for the effectiveness and efficacy of influenza vaccines in LMICs and to explore critical knowledge gaps. Methods: PubMed, EMBASE, and Cochrane were searched for seasonal and pandemic A (H1N1) 2009 influenza vaccine effectiveness and efficacy studies performed in LMICs. Eligible studies included RCTs and observational studies, published in English, French, Spanish or Portuguese between 1960 and 2011, which assessed laboratory-confirmed influenza and/or influenza-related outcomes in any population. Risk of bias was assessed by two reviewers independently. Random effects pooled estimates were obtained when sufficient data were available. Results: A total of 6465 articles were screened. Forty-one studies were included on seasonal influenza vaccine effectiveness and efficacy and one study on pandemic vaccine effectiveness. In middle income countries (MICs), efficacy of seasonal influenza vaccines was shown against laboratory-confirmed influenza in children (pooled efficacy 72% (95%CI: 65-77) and 81% (95%CI: 69-89), for one and two years follow-up respectively) and in the elderly (pooled efficacy 43% (95%CI: 25-56) and 58% (95%CI: 23-78), for live attenuated and inactivated vaccine respectively). Inactivated influenza vaccines were also found to be effective against cardiovascular outcomes in patients with coronary syndromes. Conclusions: Seasonal influenza vaccines can provide protection in children, the elderly and patients with coronary syndromes in MICs, and seem to be equally effective as compared to high income countries. Data for other high risk groups and from low income countries were limited or prone to bias, and are needed to further facilitate evidence-based decision making regarding influenza vaccination in LMICs.

Efficacy of live oral rotavirus vaccines by duration of follow-up : a meta-regression of randomised controlled trials

Clark, A., van Zandvoort, K., Flasche, S., Sanderson, C., Bines, J., Tate, J., Parashar, U., & Jit, M. (n.d.).

Publication year

2019

Journal title

The Lancet Infectious Diseases

Volume

19

Issue

7

Page(s)

717-727

10.1016/S1473-3099(19)30126-4

Abstract

Abstract

Background: The duration of protection offered by rotavirus vaccines varies across the world, and this variation is important to understanding and predicting the effects of the vaccines. There is now a large body of evidence on the efficacy of live oral rotavirus vaccines in different settings, but these data have never been synthesised to obtain robust estimates of efficacy by duration of follow-up. Our aim is to estimate the efficacy of live oral rotavirus vaccines at each point during follow-up and by mortality stratum. Methods: In our meta-regression study, we identified all randomised controlled trials of rotavirus vaccines published until April 4, 2018, using the results of a Cochrane systematic review, and cross checked these studies against those identified by another systematic review. We excluded trials that were based on special populations, trials without an infant schedule, and trials without clear reporting of numbers of enrolled infants and events in different periods of follow-up. For all reported periods of follow-up, we extracted the mean duration of follow-up (time since administration of the final dose of rotavirus vaccination), the number of enrolled infants, and case counts for rotavirus-positive severe gastroenteritis in both non-vaccinated and vaccinated groups. We used a Bayesian hierarchical Poisson meta-regression model to estimate the pooled cumulative vaccine efficacy (VE) and its waning with time for three mortality strata. We then converted these VE estimates into instantaneous VE (iVE). Findings: In settings with low mortality (15 observations), iVE pooled for infant schedules of Rotarix and RotaTeq was 98% (95% credibility interval 93–100) 2 weeks following the final dose of vaccination and 94% (87–98) after 12 months. In medium-mortality settings (11 observations), equivalent estimates were 82% (74–92) after 2 weeks and 77% (67–84) after 12 months. In settings with high mortality (24 observations), there were five different vaccines with observation points for infant schedules. The pooled iVE was 66% (48–81) after 2 weeks of follow-up and 44% (27–59) after 12 months. Interpretation: Rotavirus vaccine efficacy is lower and wanes more rapidly in high-mortality settings than in low-mortality settings, but the earlier peak age of disease in high-mortality settings means that live oral rotavirus vaccines are still likely to provide substantial benefit. Funding: Bill & Melinda Gates Foundation.

Ensuring access and affordability through COVID-19 vaccine research and development investments : A proposal for the options market for vaccines

Forman, R., Anderson, M., Jit, M., & Mossialos, E. (n.d.).

Publication year

2020

Journal title

Vaccine

Volume

38

Issue

39

Page(s)

6075-6077

10.1016/j.vaccine.2020.07.068

Abstract

Abstract

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Enzymes provide demographers with food for thought

Jit, M., & Gerland, P. (n.d.).

Publication year

2012

Journal title

eLife

Volume

2012

Issue

1

10.7554/eLife.00340

Abstract

Abstract

~

Equity impact of HPV vaccination on lifetime projections of cervical cancer burden among cohorts in 84 countries by global, regional, and income levels, 2010–22 : a modelling study

Abbas, K., Yoo, K. J., Prem, K., & Jit, M. (n.d.).

Publication year

2024

Journal title

EClinicalMedicine

Volume

70

10.1016/j.eclinm.2024.102524

Abstract

Abstract

Background: While human papillomavirus (HPV) vaccines have been available since 2006, the coverage has varied among countries. Our aim is to analyse the equity impact of HPV vaccination on the lifetime projections of cervical cancer burden among vaccinated cohorts of 2010–22 in 84 countries. Methods: We used WHO and UNICEF estimates of national immunisation coverage for HPV vaccination in 84 countries during 2010–22. We used PRIME (Papillomavirus Rapid Interface for Modelling and Economics) to estimate the lifetime health impact of HPV vaccination on cervical cancer burden in terms of deaths, cases, and disability-adjusted life years (DALYs) averted by vaccination in their respective countries. We generated concentration indices and curves to assess the equity impact of HPV vaccination across 84 countries. Findings: The health impact of HPV vaccination varied across the 84 countries and ranged from Switzerland to Tanzania at 2 to 34 deaths, 4 to 47 cases, and 40 to 735 DALYs averted per 1000 vaccinated adolescent girls over the lifetime of the vaccinated cohorts of 2010–22. The concentration index for the distribution of average coverage during 2010–22 among the 84 countries ranked by vaccine impact was 0.33 (95% CI: 0.27–0.40) and highlights the wide inequities in HPV vaccination coverage. Interpretation: Our findings suggested that countries with a relatively higher cervical cancer burden and thereby a relatively higher need for HPV vaccination had relatively lower coverage during 2010–22. Further, there were significant inequities in HPV vaccination coverage within the Americas, Europe, and Western Pacific regions, and in high- and low-income countries with a pro-advantaged and regressive distribution favouring countries with lower vaccine impact. Funding: Gavi, the Vaccine Alliance; Bill & Melinda Gates Foundation.

Erratum : COVID-19 vaccination in Sindh Province, Pakistan: A modelling study of health impact and cost-effectiveness (PLoS Med (2021) 18:10 (e1003815) DOI: 10.1371/journal.pmed.1003815)

Pearson, C. A., Bozzani, F., Procter, S. R., Davies, N. G., Huda, M., Jensen, H. T., Keogh-Brown, M., Khalid, M., Sweeney, S., Torres-Rueda, S., Eggo, R. M., Vassall, A., & Jit, M. (n.d.).

Publication year

2022

Journal title

PLoS Medicine

Volume

19

Issue

5

10.1371/journal.pmed.1003990

Abstract

Abstract

Reference item 35 cites the incorrect version of WHO guidance. The correct reference is: Initiative for Vaccine Research. WHO guide for standardization of economic evaluations of immunization programmes [Internet]. WHO; 2019 [cited 2021 Jan 15].

Estimated transmissibility and impact of SARS-CoV-2 lineage B.1.1.7 in England

CMMID COVID-19 Working Group, A., COVID-19 Genomics UK (COG-UK) Consortium, A., Davies, N. G., Abbott, S., Barnard, R. C., Jarvis, C. I., Kucharski, A. J., Munday, J. D., Pearson, C. A., Russell, T. W., Tully, D. C., Washburne, A. D., Wenseleers, T., Gimma, A., Waites, W., Wong, K. L., van Zandvoort, K., Silverman, J. D., Diaz-Ordaz, K., … Edmunds, W. J. (n.d.).

Publication year

2021

Journal title

Science

Volume

372

Issue

6538

10.1126/science.abg3055

Abstract

Abstract

A severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant, VOC 202012/01 (lineage B.1.1.7), emerged in southeast England in September 2020 and is rapidly spreading toward fixation. Using a variety of statistical and dynamic modeling approaches, we estimate that this variant has a 43 to 90% (range of 95% credible intervals, 38 to 130%) higher reproduction number than preexisting variants. A fitted two-strain dynamic transmission model shows that VOC 202012/01 will lead to large resurgences of COVID-19 cases. Without stringent control measures, including limited closure of educational institutions and a greatly accelerated vaccine rollout, COVID-19 hospitalizations and deaths across England in the first 6 months of 2021 were projected to exceed those in 2020. VOC 202012/01 has spread globally and exhibits a similar transmission increase (59 to 74%) in Denmark, Switzerland, and the United States.

Estimates of case-fatality ratios of measles in low-income and middle-income countries : a systematic review and modelling analysis

Portnoy, A., Jit, M., Ferrari, M., Hanson, M., Brenzel, L., & Verguet, S. (n.d.).

Publication year

2019

Journal title

The Lancet Global Health

Volume

7

Issue

4

Page(s)

e472-e481

10.1016/S2214-109X(18)30537-0

Abstract

Abstract

Background: In the 21st century, increases in immunisation coverage and decreases in under-5 mortality have substantially reduced the global burden of measles mortality. However, the assessment of measles mortality burden is highly dependent on estimates of case-fatality ratios for measles, which can vary according to geography, health systems infrastructure, prevalence of underlying risk factors, and measles endemicity. With imprecise case-fatality ratios, there is continued uncertainty about the burden of measles mortality and the effect of measles vaccination. In this study, we aimed to update the estimations of case-fatality ratios for measles, to develop a prediction model to estimate case-fatality ratios across heterogeneous groupings, and to project future case-fatality ratios for measles up to 2030. Methods: We did a review of the literature to identify studies examining measles cases and deaths in low-income and middle-income countries in all age groups from 1980 to 2016. We extracted data on case-fatality ratios for measles overall and by age, where possible. We developed and examined several types of generalised linear models and determined the best-fit model according to the Akaike information criterion. We then selected a best-fit model to estimate measles case-fatality ratios from 1990 to 2015 and projected future case-fatality ratios for measles up to 2030. Findings: We selected 124 peer-reviewed journal articles published between Jan 1, 1980, and Dec 31, 2016, for inclusion in the final review—85 community-based studies and 39 hospital-based studies. We selected a log-linear prediction model, resulting in a mean case-fatality ratio of 2·2% (95% CI 0·7–4·5) in 1990–2015. In community-based settings, the mean case-fatality ratio was 1·5% (0·5–3·1) compared with 2·9% (0·9–6·0) in hospital-based settings. The mean projected case-fatality ratio in 2016–2030 was 1·3% (0·4–3·7). Interpretation: Case-fatality ratios for measles have seen substantial declines since the 1990s. Our study provides an updated estimation of case-fatality ratios that could help to refine assessment of the effect on mortality of measles control and elimination programmes. Funding: Bill & Melinda Gates Foundation.

Estimating burden of influenza-associated influenza-like illness and severe acute respiratory infection at public healthcare facilities in Romania during the 2011/12-2015/16 influenza seasons

Gefenaite, G., Pistol, A., Popescu, R., Popovici, O., Ciurea, D., Dolk, C., Jit, M., & Gross, D. (n.d.).

Publication year

2018

Journal title

Influenza and other Respiratory Viruses

Volume

12

Issue

1

Page(s)

183-192

10.1111/irv.12525

Abstract

Abstract

Background: Influenza is responsible for substantial morbidity and mortality, but there is limited information on reliable disease burden estimates, especially from middle-income countries in the WHO European Region. Objectives: To estimate the incidence of medically attended influenza-associated influenza-like illness (ILI) and hospitalizations due to severe acute respiratory infection (SARI) presenting to public healthcare facilities in Romania. Patients/Methods: Sentinel influenza surveillance data for ILI and SARI from 2011/12-2015/16, including virological data, were used to estimate influenza-associated ILI and SARI incidence/100 000 and their 95% confidence intervals (95% CI). Results: The overall annual incidence of ILI and influenza-associated ILI per 100 000 persons in Romania varied between 68 (95% CI: 61-76) and 318 (95% CI: 298-338) and between 23 (95% CI: 19-29) and 189 (95% CI: 149-240), respectively. The highest ILI and influenza incidence was among children aged 0-4 years. We estimated that SARI incidence per 100 000 persons was 6 (95% CI: 5-7) to 9 (95% CI: 8-10), of which 2 (95% CI: 1-2) to 3 (95% CI: 2-4) were due to influenza. Up to 0.3% of the Romanian population were annually reported with ILI, and 0.01% was hospitalized with SARI, of which as much as one-third could be explained by influenza. Conclusions: This evaluation was the first study estimating influenza burden in Romania. We found that during each influenza season, a substantial number of persons in Romania suffer from influenza-related ILI or are hospitalized due to influenza-associated SARI.

Estimating costs of care for meningitis infections in low- and middle-income countries

Portnoy, A., Jit, M., Lauer, J., Blommaert, A., Ozawa, S., Stack, M., Murray, J., & Hutubessy, R. (n.d.).

Publication year

2015

Journal title

Vaccine

Volume

33

Issue

S1

Page(s)

A240-A247

10.1016/j.vaccine.2014.11.061

Abstract

Abstract

Meningitis infections are often associated with high mortality and risk of sequelae. The costs of treatment and care for meningitis are a great burden on health care systems, particularly in resource-limited settings. The objective of this study is to review data on the costs of care for meningitis in low- and middle-income countries, as well as to show how results could be extrapolated to countries without sound data.We conducted a systematic review of the literature from six databases to identify studies examining the cost of care in low- and middle-income countries for all age groups with suspected, probable, or confirmed meningitis. We extracted data on treatment costs and sequelae by infectious agent and/or pathogen, where possible. Using multiple regression analysis, a relationship between hospital costs and associated determinants was investigated in order to predict costs in countries with missing data. This relationship was used to predict treatment costs for all 144 low- and middle-income countries.The methodology of conducting a systematic review, extrapolating, and setting up a standard database can be used as a tool to inform cost-effectiveness analyses in situations where cost of care data are poor. Both acute and long-term costs of meningitis could be extrapolated to countries without reliable data. Although only bacterial causes of meningitis can be vaccine-preventable, a better understanding of the treatment costs for meningitis is crucial for low- and middle-income countries to assess the cost-effectiveness of proposed interventions in their country. This cost information will be important as inputs in future cost-effectiveness studies, particularly for vaccines.

Estimating global and regional between-country inequality in routine childhood vaccine coverage in 195 countries and territories from 2019 to 2021 : a longitudinal study

Lai, X., Zhang, H., Pouwels, K. B., Patenaude, B., Jit, M., & Fang, H. (n.d.).

Publication year

2023

Journal title

EClinicalMedicine

Volume

60

10.1016/j.eclinm.2023.102042

Abstract

Abstract

Background: Global routine childhood vaccine coverage has plateaued in recent years, and the COVID-19 pandemic further disrupted immunisation services. We estimated global and regional inequality of routine childhood vaccine coverage from 2019 to 2021, particularly assessing the impacts of the COVID-19 pandemic. Methods: We used longitudinal data for 11 routine childhood vaccines from the WHO-UNICEF Estimates of National Immunization Coverage (WUENIC), including 195 countries and territories in 2019–2021. The slope index of inequality (SII) and relative index of inequality (RII) of each vaccine were calculated through linear regression to express the difference in coverage between the top and bottom 20% of countries at the global and regional levels. We also explored inequalities of routine childhood vaccine coverage by WHO regions and unvaccinated children by income groups. Findings: Globally between January 1, 2019 and December 31, 2021, most childhood vaccines showed a declining trend in coverage, and therefore an increasing number of unvaccinated children, especially in low-income and lower-middle-income countries. Between-country inequalities existed for all 11 routine childhood vaccine coverage indicators. The SII for the third dose of diphtheria-tetanus-pertussis-containing vaccine (DTP3) coverage was 20.1 percentage points (95% confidence interval: 13.7, 26.5) in 2019, and rose to 23.6 (17.5, 30.0) in 2020 and 26.9 (20.0, 33.8) in 2021. Similar patterns were found for RII results and in other routine vaccines. In 2021, the second dose of measles-containing vaccine (MCV2) coverage had the highest global absolute inequality (31.2, [21.5–40.8]), and completed rotavirus vaccine (RotaC) coverage had the lowest (7.8, [–3.9, 19.5]). Among six WHO regions, the European Region consistently had the lowest inequalities, and the Western Pacific Region had the largest inequalities for many indicators, although both increased from 2019 to 2021. Interpretation: Global and regional inequalities of routine childhood vaccine coverage persisted and substantially increased from 2019 to 2021. These findings reveal economic-related inequalities by vaccines, regions, and countries, and underscore the importance of reducing such inequalities. These inequalities were widened during the COVID-19 pandemic, resulting in even lower coverage and more unvaccinated children in low-income countries. Funding: Bill & Melinda Gates Foundation.

Estimating national-level measles case–fatality ratios in low-income and middle-income countries : an updated systematic review and modelling study

Sbarra, A. N., Mosser, J. F., Jit, M., Ferrari, M., Ramshaw, R. E., O'Connor, P., Krause, L. K., Rogowski, E. L., & Portnoy, A. (n.d.).

Publication year

2023

Journal title

The Lancet Global Health

Volume

11

Issue

4

Page(s)

e516-e524

10.1016/S2214-109X(23)00043-8

Abstract

Abstract

Background: To understand the current measles mortality burden, and to mitigate the future burden, it is crucial to have robust estimates of measles case fatalities. Estimates of measles case–fatality ratios (CFRs) that are specific to age, location, and time are essential to capture variations in underlying population-level factors, such as vaccination coverage and measles incidence, which contribute to increases or decreases in CFRs. In this study, we updated estimates of measles CFRs by expanding upon previous systematic reviews and implementing a meta-regression model. Our objective was to use all information available to estimate measles CFRs in low-income and middle-income countries (LMICs) by country, age, and year. Methods: For this systematic review and meta-regression modelling study, we searched PubMed on Dec 31, 2020 for all available primary data published from Jan 1, 1980 to Dec 31, 2020, on measles cases and fatalities occurring up to Dec 31, 2019 in LMICs. We included studies that previous systematic reviews had included or which contained primary data on measles cases and deaths from hospital-based, community-based, or surveillance-based reports, including outbreak investigations. We excluded studies that were not in humans, or reported only data that were only non-primary, or on restricted populations (eg, people living with HIV), or on long-term measles mortality (eg, death from subacute sclerosing panencephalitis), and studies that did not include country-level data or relevant information on measles cases and deaths, or were for a high-income country. We extracted summary data on measles cases and measles deaths from studies that fitted our inclusion and exclusion criteria. Using these data and a suite of covariates related to measles CFRs, we implemented a Bayesian meta-regression model to produce estimates of measles CFRs from 1990 to 2019 by location and age group. This study was not registered with PROSPERO or otherwise. Findings: We identified 2705 records, of which 208 sources contained information on both measles cases and measles deaths in LMICS and were included in the review. Between 1990 and 2019, CFRs substantially decreased in both community-based and hospital-based settings, with consistent patterns across age groups. For people aged 0–34 years, we estimated a mean CFR for 2019 of 1·32% (95% uncertainty interval [UI] 1·28–1·36) among community-based settings and 5·35% (5·08–5·64) among hospital-based settings. We estimated the 2019 CFR in community-based settings to be 3·03% (UI 2·89–3·16) for those younger than 1 year, 1·63% (1·58–1·68) for age 1–4 years, 0·84% (0·80–0·87) for age 5–9 years, and 0·67% (0·64–0·70) for age 10–14 years. Interpretation: Although CFRs have declined between 1990 and 2019, there are still large heterogeneities across locations and ages. One limitation of this systematic review is that we were unable to assess measles CFR among particular populations, such as refugees and internally displaced people. Our updated methodological framework and estimates could be used to evaluate the effect of measles control and vaccination programmes on reducing the preventable measles mortality burden. Funding: Bill & Melinda Gates Foundation; Gavi, the Vaccine Alliance; and the US National Institutes of Health.

Estimating number of cases and spread of coronavirus disease (COVID-19) using critical care admissions, United Kingdom, February to March 2020

LSHTM Centre for Mathematical Modelling ofInfectious Diseases COVID-19 Working Group, A., Jit, M., Jombart, T., Nightingale, E. S., Endo, A., Abbott, S., & Edmunds, W. J. (n.d.).

Publication year

2020

Journal title

Eurosurveillance

Volume

25

Issue

18

Page(s)

1-5

10.2807/1560-7917.ES.2020.25.18.2000632

Abstract

Abstract

An exponential growth model was fitted to critical care admissions from two surveillance databases to determine likely coronavirus disease (COVID-19) case numbers, critical care admissions and epidemic growth in the United Kingdom before the national lockdown. We estimate, on 23 March, a median of 114,000 (95% credible interval (CrI): 78,000–173,000) new cases and 258 (95% CrI: 220–319) new critical care reports, with 527,000 (95% CrI: 362,000–797,000) cumulative cases since 16 February.

Estimating progression rates for human papillomavirus infection from epidemiological data

Jit, M., Gay, N., Soldan, K., Hong Choi, Y., & Edmunds, W. J. (n.d.).

Publication year

2010

Journal title

Medical Decision Making

Volume

30

Issue

1

Page(s)

84-98

10.1177/0272989X09336140

Abstract

Abstract

A Markov model was constructed in order to estimate typespecific rates of cervical lesion progression and regression in women with high-risk human papillomavirus (HPV). The model was fitted to age- and type-specific data regarding the HPV DNA and cytological status of women undergoing cervical screening in a recent screening trial, as well as cervical cancer incidence. It incorporates different assumptions about the way lesions regress, the accuracy of cytological screening, the specificity of HPV DNA testing, and the age-specific prevalence of HPV infection. Combinations of assumptions generate 162 scenarios for squamous cell carcinomas and 54 scenarios for adenocarcinomas. Simulating an unscreened cohort of women infected with high-risk HPV indicates that the probability of an infection continuing to persist and to develop into invasive cancer depends on the length of time it has already persisted. The scenarios and parameter sets that produce the best fit to available epidemiological data provide a basis for modeling the natural history of HPV infection and disease.

Estimating the cost-effectiveness of maternal vaccination and monoclonal antibodies for respiratory syncytial virus in Kenya and South Africa

Koltai, M., Moyes, J., Nyawanda, B., Nyiro, J., Munywoki, P. K., Tempia, S., Li, X., Antillon, M., Bilcke, J., Flasche, S., Beutels, P., Nokes, D. J., Cohen, C., & Jit, M. (n.d.).

Publication year

2023

Journal title

BMC Medicine

Volume

21

Issue

1

10.1186/s12916-023-02806-w

Abstract

Abstract

Background: Respiratory syncytial virus (RSV) causes a substantial burden of acute lower respiratory infection in children under 5 years, particularly in low- and middle-income countries (LMICs). Maternal vaccine (MV) and next-generation monoclonal antibody (mAb) candidates have been shown to reduce RSV disease in infants in phase 3 clinical trials. The cost-effectiveness of these biologics has been estimated using disease burden data from global meta-analyses, but these are sensitive to the detailed age breakdown of paediatric RSV disease, for which there have previously been limited data. Methods: We use original hospital-based incidence data from South Africa (ZAF) and Kenya (KEN) collected between 2010 and 2018 of RSV-associated acute respiratory infection (ARI), influenza-like illness (ILI), and severe acute respiratory infection (SARI) as well as deaths with monthly age-stratification, supplemented with data on healthcare-seeking behaviour and costs to the healthcare system and households. We estimated the incremental cost per DALY averted (incremental cost-effectiveness ratio or ICER) of public health interventions by MV or mAb for a plausible range of prices (5–50 USD for MV, 10–125 USD for mAb), using an adjusted version of a previously published health economic model of RSV immunisation. Results: Our data show higher disease incidence for infants younger than 6 months of age in the case of Kenya and South Africa than suggested by earlier projections from community incidence-based meta-analyses of LMIC data. Since MV and mAb provide protection for these youngest age groups, this leads to a substantially larger reduction of disease burden and, therefore, more favourable cost-effectiveness of both interventions in both countries. Using the latest efficacy data and inferred coverage levels based on antenatal care (ANC-3) coverage (KEN: 61.7%, ZAF: 75.2%), our median estimate of the reduction in RSV-associated deaths in children under 5 years in Kenya is 10.5% (95% CI: 7.9, 13.3) for MV and 13.5% (10.7, 16.4) for mAb, while in South Africa, it is 27.4% (21.6, 32.3) and 37.9% (32.3, 43.0), respectively. Starting from a dose price of 5 USD, in Kenya, net cost (for the healthcare system) per (undiscounted) DALY averted for MV is 179 (126, 267) USD, rising to 1512 (1166, 2070) USD at 30 USD per dose; for mAb, it is 684 (543, 895) USD at 20 USD per dose and 1496 (1203, 1934) USD at 40 USD per dose. In South Africa, a MV at 5 USD per dose would be net cost-saving for the healthcare system and net cost per DALY averted is still below the ZAF’s GDP per capita at 40 USD dose price (median: 2350, 95% CI: 1720, 3346). For mAb in ZAF, net cost per DALY averted is 247 (46, 510) USD at 20 USD per dose, rising to 2028 (1565, 2638) USD at 50 USD per dose and to 6481 (5364, 7959) USD at 125 USD per dose. Conclusions: Incorporation of new data indicating the disease burden is highly concentrated in the first 6 months of life in two African settings suggests that interventions against RSV disease may be more cost-effective than previously estimated.

Estimating the effectiveness of routine asymptomatic PCR testing at different frequencies for the detection of SARS-CoV-2 infections

CMMID COVID-19 Working Group, A., The SAFER Investigators and Field Study Team, A., The Crick COVID-19 Consortium, A., Hellewell, J., Russell, T. W., Matthews, R., Severn, A., Adam, S., Enfield, L., McBride, A., Gärtner, K., Edwards, S., Lorencatto, F., Michie, S., Manley, E., Shahmanesh, M., Lukha, H., Prymas, P., McBain, H., … Jit, M. (n.d.).

Publication year

2021

Journal title

BMC Medicine

Volume

19

Issue

1

10.1186/s12916-021-01982-x

Abstract

Abstract

Background: Routine asymptomatic testing using RT-PCR of people who interact with vulnerable populations, such as medical staff in hospitals or care workers in care homes, has been employed to help prevent outbreaks among vulnerable populations. Although the peak sensitivity of RT-PCR can be high, the probability of detecting an infection will vary throughout the course of an infection. The effectiveness of routine asymptomatic testing will therefore depend on testing frequency and how PCR detection varies over time. Methods: We fitted a Bayesian statistical model to a dataset of twice weekly PCR tests of UK healthcare workers performed by self-administered nasopharyngeal swab, regardless of symptoms. We jointly estimated times of infection and the probability of a positive PCR test over time following infection; we then compared asymptomatic testing strategies by calculating the probability that a symptomatic infection is detected before symptom onset and the probability that an asymptomatic infection is detected within 7 days of infection. Results: We estimated that the probability that the PCR test detected infection peaked at 77% (54–88%) 4 days after infection, decreasing to 50% (38–65%) by 10 days after infection. Our results suggest a substantially higher probability of detecting infections 1–3 days after infection than previously published estimates. We estimated that testing every other day would detect 57% (33–76%) of symptomatic cases prior to onset and 94% (75–99%) of asymptomatic cases within 7 days if test results were returned within a day. Conclusions: Our results suggest that routine asymptomatic testing can enable detection of a high proportion of infected individuals early in their infection, provided that the testing is frequent and the time from testing to notification of results is sufficiently fast.

Estimating the global impact of rotavirus vaccines on child mortality

Clark, A., Mahmud, S., Debellut, F., Pecenka, C., Jit, M., Perin, J., Tate, J., Soeters, H. M., Black, R. E., Santosham, M., & Sanderson, C. (n.d.).

Publication year

2023

Journal title

International Journal of Infectious Diseases

Volume

137

Page(s)

90-97

10.1016/j.ijid.2023.10.005

Abstract

Abstract

Objectives: We estimated the global impact of rotavirus vaccines on deaths among children under five years old by year. Methods: We used a proportionate outcomes model with a finely disaggregated age structure to estimate rotavirus deaths prevented by vaccination over the period 2006-2019 in 186 countries. We ran deterministic and probabilistic uncertainty analyses and compared our estimates to surveillance-based estimates in 20 countries. Results: We estimate that rotavirus vaccines prevented 139,000 under-five rotavirus deaths (95% uncertainty interval 98,000-201,000) in the period 2006-2019. In 2019 alone, rotavirus vaccines prevented 15% (95% uncertainty interval 11-21%) of under-five rotavirus deaths (0.5% of child mortality). Assuming global use of rotavirus vaccines and coverage equivalent to other co-administered vaccines could prevent 37% of under-five rotavirus deaths (1.2% of child mortality). Our estimates were sensitive to the choice of rotavirus mortality burden data and several vaccine impact modeling assumptions. The World Health Organization's recommendation to remove age restrictions in 2012 could have prevented up to 17,000 rotavirus deaths in the period 2013-2019. Our modeled estimates of rotavirus vaccine impact were broadly consistent with estimates from post-vaccination surveillance sites. Conclusion: Rotavirus vaccines have made a valuable contribution to global public health. Enhanced rotavirus mortality prevention strategies are needed in countries with high mortality in under-5-year-old children.

Estimating the health effects of COVID-19-related immunisation disruptions in 112 countries during 2020–30 : a modelling study

Hartner, A. M., Li, X., Echeverria-Londono, S., Roth, J., Abbas, K., Auzenbergs, M., de Villiers, M. J., Ferrari, M. J., Fraser, K., Fu, H., Hallett, T., Hinsley, W., Jit, M., Karachaliou, A., Moore, S. M., Nayagam, S., Papadopoulos, T., Perkins, T. A., Portnoy, A., … Gaythorpe, K. A. (n.d.).

Publication year

2024

Journal title

The Lancet Global Health

Volume

12

Issue

4

Page(s)

e563-e571

10.1016/S2214-109X(23)00603-4

Abstract

Abstract

Background: There have been declines in global immunisation coverage due to the COVID-19 pandemic. Recovery has begun but is geographically variable. This disruption has led to under-immunised cohorts and interrupted progress in reducing vaccine-preventable disease burden. There have, so far, been few studies of the effects of coverage disruption on vaccine effects. We aimed to quantify the effects of vaccine-coverage disruption on routine and campaign immunisation services, identify cohorts and regions that could particularly benefit from catch-up activities, and establish if losses in effect could be recovered. Methods: For this modelling study, we used modelling groups from the Vaccine Impact Modelling Consortium from 112 low-income and middle-income countries to estimate vaccine effect for 14 pathogens. One set of modelling estimates used vaccine-coverage data from 1937 to 2021 for a subset of vaccine-preventable, outbreak-prone or priority diseases (ie, measles, rubella, hepatitis B, human papillomavirus [HPV], meningitis A, and yellow fever) to examine mitigation measures, hereafter referred to as recovery runs. The second set of estimates were conducted with vaccine-coverage data from 1937 to 2020, used to calculate effect ratios (ie, the burden averted per dose) for all 14 included vaccines and diseases, hereafter referred to as full runs. Both runs were modelled from Jan 1, 2000, to Dec 31, 2100. Countries were included if they were in the Gavi, the Vaccine Alliance portfolio; had notable burden; or had notable strategic vaccination activities. These countries represented the majority of global vaccine-preventable disease burden. Vaccine coverage was informed by historical estimates from WHO–UNICEF Estimates of National Immunization Coverage and the immunisation repository of WHO for data up to and including 2021. From 2022 onwards, we estimated coverage on the basis of guidance about campaign frequency, non-linear assumptions about the recovery of routine immunisation to pre-disruption magnitude, and 2030 endpoints informed by the WHO Immunization Agenda 2030 aims and expert consultation. We examined three main scenarios: no disruption, baseline recovery, and baseline recovery and catch-up. Findings: We estimated that disruption to measles, rubella, HPV, hepatitis B, meningitis A, and yellow fever vaccination could lead to 49 119 additional deaths (95% credible interval [CrI] 17 248–134 941) during calendar years 2020–30, largely due to measles. For years of vaccination 2020–30 for all 14 pathogens, disruption could lead to a 2·66% (95% CrI 2·52–2·81) reduction in long-term effect from 37 378 194 deaths averted (34 450 249–40 241 202) to 36 410 559 deaths averted (33 515 397–39 241 799). We estimated that catch-up activities could avert 78·9% (40·4–151·4) of excess deaths between calendar years 2023 and 2030 (ie, 18 900 [7037–60 223] of 25 356 [9859–75 073]). Interpretation: Our results highlight the importance of the timing of catch-up activities, considering estimated burden to improve vaccine coverage in affected cohorts. We estimated that mitigation measures for measles and yellow fever were particularly effective at reducing excess burden in the short term. Additionally, the high long-term effect of HPV vaccine as an important cervical-cancer prevention tool warrants continued immunisation efforts after disruption. Funding: The Vaccine Impact Modelling Consortium, funded by Gavi, the Vaccine Alliance and the Bill & Melinda Gates Foundation. Translations: For the Arabic, Chinese, French, Portguese and Spanish translations of the abstract see Supplementary Materials section.

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

Vaccine Impact Modelling Consortium, A., Li, X., Mukandavire, C., Cucunubá, Z. M., Echeverria Londono, S., Abbas, K., Clapham, H. E., Jit, M., Johnson, H. L., Papadopoulos, T., Vynnycky, E., Brisson, M., Carter, E. D., Clark, A., de Villiers, M. J., Eilertson, K., Ferrari, M. J., Gamkrelidze, I., Gaythorpe, K. A., … Garske, T. (n.d.).

Publication year

2021

Journal title

The Lancet

Volume

397

Issue

10272

Page(s)

398-408

10.1016/S0140-6736(20)32657-X

Abstract

Abstract

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

Estimating the Hospital Burden of Norovirus-Associated Gastroenteritis in England and Its Opportunity Costs for Nonadmitted Patients

Sandmann, F. G., Shallcross, L., Adams, N., Allen, D. J., Coen, P. G., Jeanes, A., Kozlakidis, Z., Larkin, L., Wurie, F., Robotham, J. V., Jit, M., & Deeny, S. R. (n.d.).

Publication year

2018

Journal title

Clinical Infectious Diseases

Volume

67

Issue

5

Page(s)

693-700

10.1093/cid/ciy167

Abstract

Abstract

Background. Norovirus places a substantial burden on healthcare systems, arising from infected patients, disease outbreaks, beds kept unoccupied for infection control, and staff absences due to infection. In settings with high rates of bed occupancy, opportunity costs arise from patients who cannot be admitted due to beds being unavailable. With several treatments and vaccines against norovirus in development, quantifying the expected economic burden is timely. Methods. The number of inpatients with norovirus-associated gastroenteritis in England was modeled using infectious and noninfectious gastrointestinal Hospital Episode Statistics codes and laboratory reports of gastrointestinal pathogens collected at Public Health England. The excess length of stay from norovirus was estimated with a multistate model and local outbreak data. Unoccupied bed-days and staff absences were estimated from national outbreak surveillance. The burden was valued conventionally using accounting expenditures and wages, which we contrasted to the opportunity costs from forgone patients using a novel methodology. Results. Between July 2013 and June 2016, 17.7% (95% confidence interval [CI], 15.6%?21.6%) of primary and 23.8% (95% CI,20.6%?29.9%) of secondary gastrointestinal diagnoses were norovirus attributable. Annually, the estimated median 290 000 (interquartile range, 282 000?297 000) occupied and unoccupied bed-days used for norovirus displaced 57 800 patients. Conventional costs for the National Health Service reached 107.6 million; the economic burden approximated to 297.7 million and a loss of 6300 quality-adjusted life-years annually. Conclusions. In England, norovirus is now the second-largest contributor of the gastrointestinal hospital burden. With the projected impact being greater than previously estimated, improved capture of relevant opportunity costs seems imperative for diseases such as norovirus.

Estimating the impact of reopening schools on the reproduction number of SARS-CoV-2 in England, using weekly contact survey data

CMMID COVID-19 Working Group, A., Munday, J. D., Jarvis, C. I., Gimma, A., Wong, K. L., van Zandvoort, K., Liu, Y., Hellewell, J., Davies, N. G., Villabona-Arenas, C. J., Eggo, R. M., Endo, A., Bosse, N. I., Gibbs, H. P., Pearson, C. A., Sun, F. Y., Jit, M., O’Reilly, K., Jafari, Y., … Edmunds, W. J. (n.d.).

Publication year

2021

Journal title

BMC Medicine

Volume

19

Issue

1

10.1186/s12916-021-02107-0

Abstract

Abstract

Background: Schools were closed in England on 4 January 2021 as part of increased national restrictions to curb transmission of SARS-CoV-2. The UK government reopened schools on 8 March. Although there was evidence of lower individual-level transmission risk amongst children compared to adults, the combined effects of this with increased contact rates in school settings and the resulting impact on the overall transmission rate in the population were not clear. Methods: We measured social contacts of > 5000 participants weekly from March 2020, including periods when schools were both open and closed, amongst other restrictions. We combined these data with estimates of the susceptibility and infectiousness of children compared with adults to estimate the impact of reopening schools on the reproduction number. Results: Our analysis indicates that reopening all schools under the same measures as previous periods that combined lockdown with face-to-face schooling would be likely to increase the reproduction number substantially. Assuming a baseline of 0.8, we estimated a likely increase to between 1.0 and 1.5 with the reopening of all schools or to between 0.9 and 1.2 reopening primary or secondary schools alone. Conclusion: Our results suggest that reopening schools would likely halt the fall in cases observed between January and March 2021 and would risk a return to rising infections, but these estimates relied heavily on the latest estimates or reproduction number and the validity of the susceptibility and infectiousness profiles we used at the time of reopening.