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

Human papillomavirus vaccine effectiveness by number of doses : Updated systematic review of data from national immunization programs

Markowitz, L. E., Drolet, M., Lewis, R. M., Lemieux-Mellouki, P., Pérez, N., Jit, M., Brotherton, J. M., Ogilvie, G., Kreimer, A. R., & Brisson, M. (n.d.).

Publication year

2022

Journal title

Vaccine

Volume

40

Issue

37

Page(s)

5413-5432

10.1016/j.vaccine.2022.06.065

Abstract

Abstract

Background: Human papillomavirus (HPV) vaccines were first licensed as a three-dose series. Two doses are now widely recommended in some age groups; there are data suggesting high efficacy with one dose. We updated a systematic literature review of HPV vaccine effectiveness by number of doses in observational studies. Methods: We searched Medline and Embase databases from January 1, 2007, through September 29, 2021. Data were extracted and summarized in a narrative synthesis. We also conducted quality assessments for bias due to selection, information, and confounding. Results: Overall, 35 studies were included; all except one were conducted within the context of a recommended three-dose schedule. Evaluations were in countries that used bivalent HPV vaccine (seven), quadrivalent HPV vaccine (27) or both (one). Nine evaluated effectiveness against HPV infection, ten anogenital warts, and 16 cervical abnormalities. All studies were judged to have moderate or serious risk of bias. The biases rated as serious would likely result in lower effectiveness with fewer doses. Investigators attempted to control for or stratify by potentially important variables, such as age at vaccination. Eight studies evaluated impact of buffer periods (lag time) for case counting and 10 evaluated different intervals between doses for two-dose vaccine recipients. Studies that stratified by vaccination age found higher effectiveness with younger age at vaccination, although differences were not all formally tested. Most studies found highest estimates of effectiveness with three doses; significant effectiveness was found among 28/29 studies that evaluated three doses, 19/29 that evaluated two doses, and 18/30 that evaluated one dose. Some studies that adjusted or stratified analyses by age at vaccination found similar effectiveness with three, two and one doses. Conclusion: Observational studies of HPV vaccine effectiveness have many biases. Studies examining persons vaccinated prior to sexual activity and using methods to reduce sources of bias are needed for valid effectiveness estimates.

In Elimination Settings, Measles Antibodies Wane After Vaccination but Not After Infection : A Systematic Review and Meta-Analysis

Bolotin, S., Osman, S., Hughes, S. L., Ariyarajah, A., Tricco, A. C., Khan, S., Li, L., Johnson, C., Friedman, L., Gul, N., Jardine, R., Faulkner, M., Hahné, S. J., Heffernan, J. M., Dabbagh, A., Rota, P. A., Severini, A., Jit, M., Durrheim, D. N., … Crowcroft, N. S. (n.d.).

Publication year

2022

Journal title

Journal of Infectious Diseases

Volume

226

Issue

7

Page(s)

1127-1139

10.1093/infdis/jiac039

Abstract

Abstract

Background: We conducted a systematic review to assess whether measles humoral immunity wanes in previously infected or vaccinated populations in measles elimination settings. Methods: After screening 16 822 citations, we identified 9 articles from populations exposed to wild-type measles and 16 articles from vaccinated populations that met our inclusion criteria. Results: Using linear regression, we found that geometric mean titers (GMTs) decreased significantly in individuals who received 2 doses of measles-containing vaccine (MCV) by 121.8 mIU/mL (95% confidence interval [CI], -212.4 to -31.1) per year since vaccination over 1 to 5 years, 53.7 mIU/mL (95% CI, -95.3 to -12.2) 5 to 10 years, 33.2 mIU/mL (95% CI, -62.6 to -3.9), 10 to 15 years, and 24.1 mIU/mL (95% CI, -51.5 to 3.3) 15 to 20 years since vaccination. Decreases in GMT over time were not significant after 1 dose of MCV or after infection. Decreases in the proportion of seropositive individuals over time were not significant after 1 or 2 doses of MCV or after infection. Conclusions: Measles antibody waning in vaccinated populations should be considered in planning for measles elimination.

Integrating economic and health evidence to inform Covid-19 policy in low- and middle- income countries

Vassall, A., Sweeney, S., Barasa, E., Prinja, S., Keogh-Brown, M. R., Tarp Jensen, H., Smith, R., Baltussen, R., M Eggo, R., & Jit, M. (n.d.).

Publication year

2022

Journal title

Wellcome Open Research

Volume

5

10.12688/wellcomeopenres.16380.2

Abstract

Abstract

Covid-19 requires policy makers to consider evidence on both population health and economic welfare. Over the last two decades, the field of health economics has developed a range of analytical approaches and contributed to the institutionalisation of processes to employ economic evidence in health policy. We present a discussion outlining how these approaches and processes need to be applied more widely to inform Covid-19 policy; highlighting where they may need to be adapted conceptually and methodologically, and providing examples of work to date. We focus on the evidential and policy needs of low- and middle-income countries; where there is an urgent need for evidence to navigate the policy trade-offs between health and economic well-being posed by the Covid-19 pandemic.

Long-Term Health-Related Quality of Life in Non-Hospitalized Coronavirus Disease 2019 (COVID-19) Cases With Confirmed Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Infection in England : Longitudinal Analysis and Cross-Sectional Comparison With Controls

Sandmann, F. G., Tessier, E., Lacy, J., Kall, M., Van Leeuwen, E., Charlett, A., Eggo, R. M., Dabrera, G., Edmunds, W. J., Ramsay, M., Campbell, H., Amirthalingam, G., & Jit, M. (n.d.).

Publication year

2022

Journal title

Clinical Infectious Diseases

Volume

75

Issue

1

Page(s)

E962-E973

10.1093/cid/ciac151

Abstract

Abstract

Background: We aimed to quantify the unknown losses in health-related quality of life of coronavirus disease 2019 (COVID-19) cases using quality-adjusted lifedays (QALDs) and the recommended EQ-5D instrument in England. Methods: Prospective cohort study of nonhospitalized, polymerase chain reaction (PCR)-confirmed severe acute respiratory syndrome coronavirus 2-positive (SARS-CoV-2-positive) cases aged 12-85 years and followed up for 6 months from 1 December 2020, with cross-sectional comparison to SARS-CoV-2-negative controls. Main outcomes were QALD losses; physical symptoms; and COVID-19-related private expenditures. We analyzed results using multivariable regressions with post hoc weighting by age and sex, and conditional logistic regressions for the association of each symptom and EQ-5D limitation on cases and controls. Results: Of 548 cases (mean age 41.1 years; 61.5% female), 16.8% reported physical symptoms at month 6 (most frequently extreme tiredness, headache, loss of taste and/or smell, and shortness of breath). Cases reported more limitations with doing usual activities than controls. Almost half of cases spent a mean of £18.1 on nonprescription drugs (median: £10.0), and 52.7% missed work or school for a mean of 12 days (median: 10). On average, all cases lost 13.7 (95% confidence interval [CI]: 9.7, 17.7) QALDs, whereas those reporting symptoms at month 6 lost 32.9 (95% CI: 24.5, 37.6) QALDs. Losses also increased with older age. Cumulatively, the health loss from morbidity contributes at least 18% of the total COVID-19-related disease burden in the England. Conclusions: One in 6 cases report ongoing symptoms at 6 months, and 10% report prolonged loss of function compared to pre-COVID-19 baselines. A marked health burden was observed among older COVID-19 cases and those with persistent physical symptoms.

Measuring the effects of COVID-19-related disruption on dengue transmission in southeast Asia and Latin America : a statistical modelling study

CMMID COVID-19 Working Group, A., Chen, Y., Li, N., Lourenço, J., Wang, L., Cazelles, B., Dong, L., Li, B., Liu, Y., Jit, M., Bosse, N. I., Abbott, S., Velayudhan, R., Wilder-Smith, A., Tian, H., Brady, O. J., Procter, S. R., Wong, K. L., Hellewell, J., … Gimma, A. (n.d.).

Publication year

2022

Journal title

The Lancet Infectious Diseases

Volume

22

Issue

5

Page(s)

657-667

10.1016/S1473-3099(22)00025-1

Abstract

Abstract

Background: The COVID-19 pandemic has resulted in unprecedented disruption to society, which indirectly affects infectious disease dynamics. We aimed to assess the effects of COVID-19-related disruption on dengue, a major expanding acute public health threat, in southeast Asia and Latin America. Methods: We assembled data on monthly dengue incidence from WHO weekly reports, climatic data from ERA5, and population variables from WorldPop for 23 countries between January, 2014 and December, 2019 and fit a Bayesian regression model to explain and predict seasonal and multi-year dengue cycles. We compared model predictions with reported dengue data January to December, 2020, and assessed if deviations from projected incidence since March, 2020 are associated with specific public health and social measures (from the Oxford Coronavirus Government Response Tracer database) or human movement behaviours (as measured by Google mobility reports). Findings: We found a consistent, prolonged decline in dengue incidence across many dengue-endemic regions that began in March, 2020 (2·28 million cases in 2020 vs 4·08 million cases in 2019; a 44·1% decrease). We found a strong association between COVID-19-related disruption (as measured independently by public health and social measures and human movement behaviours) and reduced dengue risk, even after taking into account other drivers of dengue cycles including climatic and host immunity (relative risk 0·01–0·17, p

Modelling the medium-term dynamics of SARS-CoV-2 transmission in England in the Omicron era

Centre for Mathematical Modelling of Infectious Diseases COVID-19 Working Group, A., Barnard, R. C., Davies, N. G., Munday, J. D., Lowe, R., Knight, G. M., Leclerc, Q. J., Tully, D. C., Hodgson, D., Pung, R., Hellewell, J., Koltai, M., Simons, D., Abbas, K., Kucharski, A. J., Procter, S. R., Sandmann, F. G., Pearson, C. A., Prem, K., … Jit, M. (n.d.).

Publication year

2022

Journal title

Nature communications

Volume

13

Issue

1

10.1038/s41467-022-32404-y

Abstract

Abstract

England has experienced a heavy burden of COVID-19, with multiple waves of SARS-CoV-2 transmission since early 2020 and high infection levels following the emergence and spread of Omicron variants since late 2021. In response to rising Omicron cases, booster vaccinations were accelerated and offered to all adults in England. Using a model fitted to more than 2 years of epidemiological data, we project potential dynamics of SARS-CoV-2 infections, hospital admissions and deaths in England to December 2022. We consider key uncertainties including future behavioural change and waning immunity and assess the effectiveness of booster vaccinations in mitigating SARS-CoV-2 disease burden between October 2021 and December 2022. If no new variants emerge, SARS-CoV-2 transmission is expected to decline, with low levels remaining in the coming months. The extent to which projected SARS-CoV-2 transmission resurges later in 2022 depends largely on assumptions around waning immunity and to some extent, behaviour, and seasonality.

Neurodevelopmental and growth outcomes after invasive Group B Streptococcus in early infancy : A multi-country matched cohort study in South Africa, Mozambique, India, Kenya, and Argentina

GBS long term outcomes LMIC collaborative group, A., Paul, P., Chandna, J., Procter, S. R., Dangor, Z., Leahy, S., Santhanam, S., John, H. B., Bassat, Q., Bramugy, J., Bardají, A., Abubakar, A., Nasambu, C., Libster, R., Yanotti, C. S., Seedat, F., Horváth-Puhó, E., Hossain, A. K., Sadeq-ur Rahman, Q., … Llapur, C. J. (n.d.).

Publication year

2022

Journal title

EClinicalMedicine

Volume

47

10.1016/j.eclinm.2022.101358

Abstract

Abstract

Background: Data are limited regarding long-term consequences of invasive GBS (iGBS) disease in early infancy, especially from low- and middle-income countries (LMIC) where most cases occur. We aimed to estimate risk of neurodevelopmental impairment (NDI) in children with a history of iGBS disease. Methods: A multi-country matched cohort study was undertaken in South Africa, India, Mozambique, Kenya, and Argentina from October 2019 to April 2021. The exposure of interest was defined as a history of iGBS disease (sepsis or meningitis) before 90 days of age, amongst children now aged 1·5–18 years. Age and sex-matched, children without history of GBS were also recruited. Age-appropriate, culturally-adapted assessments were used to define NDI across multiple domains (cognitive, motor, hearing, vision, emotional-behaviour, growth). Pooled NDI risk was meta-analysed across sites. Association of iGBS exposure and NDI outcome was estimated using modified Poisson regression with robust variance estimator. Findings: Amongst 138 iGBS survivors and 390 non-iGBS children, 38·1% (95% confidence interval [CI]: 30·0% – 46·6%) of iGBS children had any NDI, compared to 21·7% (95% CI: 17·7% - 26·0%) of non- iGBS children, with notable between-site heterogeneity. Risk of moderate/severe NDI was 15·0% (95% CI: 3·4% - 30·8%) among GBS-meningitis, 5·6% (95% CI: 1·5% - 13·7%) for GBS-sepsis survivors. The adjusted risk ratio (aRR) for moderate/severe NDI among iGBS survivors was 1.27 (95% CI: 0.65, 2.45), when compared to non-GBS children. Mild impairment was more frequent in iGBS (27.6% (95% CI: 20.3 – 35.5%)) compared to non-GBS children (12.9% (95% CI: 9.7% - 16.4%)). The risk of emotional-behavioural problems was similar irrespective of iGBS exposure (aRR=0.98 (95% CI: 0.55, 1.77)). Interpretation: Our findings suggest that iGBS disease is on average associated with a higher risk of moderate/severe NDI, however substantial variation in risk was observed between sites and data are consistent with a wide range of values. Our study underlines the importance of long-term follow-up for at-risk neonates and more feasible, standardised assessments to facilitate diagnosis in research and clinical practice. Funding: This work was supported by a grant (INV-009018) from the Bill & Melinda Gates Foundation to the London School of Hygiene &Tropical Medicine.

Now or later : Health impacts of delaying single-dose HPV vaccine implementation in a high-burden setting

Burger, E. A., Laprise, J. F., Sy, S., Regan, M. C., Prem, K., Jit, M., Brisson, M., & Kim, J. J. (n.d.).

Publication year

2022

Journal title

International Journal of Cancer

Volume

151

Issue

10

Page(s)

1804-1809

10.1002/ijc.34054

Abstract

Abstract

We aimed to quantify the health impact of immediate introduction of a single-dose human papillomavirus (HPV) vaccination program in a high-burden setting, as waiting until forthcoming trials are completed to implement single-dose HPV vaccination may result in health losses, particularly for cohorts who would age-out of vaccination eligibility. Two mathematical models fitted to a high-burden setting projected cervical cancer incidence rates associated with (a) immediate implementation of one-dose HPV vaccination vs (b) waiting 5 years for evidence from randomized trials to determine if one- or two-doses should be implemented. We conducted analyses assuming a single dose was either noninferior or inferior to two doses. The models projected that immediate implementation of a noninferior single-dose vaccine led to a 7.2% to 9.6% increase in cancers averted between 2021 to 2120, compared to waiting 5 years. Health benefits remained greater with immediate implementation despite an inferior single-dose efficacy (80%), but revaccination of one-dose recipients became more important assuming vaccine waning. Under most circumstances, immediate vaccination avoided health losses for those aging out of vaccine eligibility, leading to greater health benefits than waiting for more information in 5 years.

Optimal health and economic impact of non-pharmaceutical intervention measures prior and post vaccination in England : a mathematical modelling study

Tildesley, M. J., Vassall, A., Riley, S., Jit, M., Sandmann, F., Hill, E. M., Thompson, R. N., Atkins, B. D., Edmunds, J., Dyson, L., & Keeling, M. J. (n.d.).

Publication year

2022

Journal title

Royal Society Open Science

Volume

9

Issue

8

10.1098/rsos.211746

Abstract

Abstract

Background. Even with good progress on vaccination, SARS-CoV-2 infections in the UK may continue to impose a high burden of disease and therefore pose substantial challenges for health policy decision makers. Stringent government-mandated physical distancing measures (lockdown) have been demonstrated to be epidemiologically effective, but can have both positive and negative economic consequences. The duration and frequency of any intervention policy could, in theory, be optimized to maximize economic benefits while achieving substantial reductions in disease. Methods. Here, we use a pre-existing SARS-CoV-2 transmission model to assess the health and economic implications of different strengths of control through time in order to identify optimal approaches to non-pharmaceutical intervention stringency in the UK, considering the role of vaccination in reducing the need for future physical distancing measures. The model is calibrated to the COVID-19 epidemic in England and we carry out retrospective analysis of the optimal timing of precautionary breaks in 2020 and the optimal relaxation policy from the January 2021 lockdown, considering the willingness to pay (WTP) for health improvement. Results. We find that the precise timing and intensity of interventions is highly dependent upon the objective of control. As intervention measures are relaxed, we predict a resurgence in cases, but the optimal intervention policy can be established dependent upon the WTP per quality adjusted life year loss avoided. Our results show that establishing an optimal level of control can result in a reduction in net monetary loss of billions of pounds, dependent upon the precise WTP value. Conclusion. It is vital, as the UK emerges from lockdown, but continues to face an on-going pandemic, to accurately establish the overall health and economic costs when making policy decisions. We demonstrate how some of these can be quantified, employing mechanistic infectious disease transmission models to establish optimal levels of control for the ongoing COVID-19 pandemic.

Optimal Respiratory Syncytial Virus intervention programmes using Nirsevimab in England and Wales

Hodgson, D., Koltai, M., Krauer, F., Flasche, S., Jit, M., & Atkins, K. E. (n.d.).

Publication year

2022

Journal title

Vaccine

Volume

40

Issue

49

Page(s)

7151-7157

10.1016/j.vaccine.2022.10.041

Abstract

Abstract

Introduction: Respiratory Syncytial Virus (RSV) is a major cause of acute lower respiratory tract infections (ALRI) in infants. There are no licensed vaccines and only one monoclonal antibody available to protect infants from disease. A new and potentially longer-lasting monoclonal antibody, Nirsevimab, showed promising results in phase IIb/III trials. We evaluate the cost-effectiveness of Nirsevimab intervention programmes in England and Wales. Methods: We used a dynamic model for RSV transmission, calibrated to data from England and Wales. We considered a suite of potential Nirsevimab programmes, including administration to all neonates (year-round); only neonates born during the RSV season (seasonal); or neonates born during the RSV season plus infants less than six months old before the start of the RSV season (seasonal + catch-up). Results: If administered seasonally to all infants at birth, we found that Nirsevimab would have to be priced at £63 or less per dose for at least 50% certainty that it could cost-effectively replace the current Palivizumab programme, using an ICER threshold of £20,000/QALY. An extended seasonal programme which includes a pre-season catch-up becomes the optimal strategy at a purchasing price of £32/dose or less for at least 50% certainty. At a purchasing price per dose of £5-32, the annual implementation costs of a seasonal programme could be as high as £2 million before a switch to a year-round strategy would be optimal. Discussion: Nirsevimab has the potential to be cost-effective in England and Wales not only for use in high-risk infants.

Optimising health and economic impacts of COVID-19 vaccine prioritisation strategies in the WHO European Region : a mathematical modelling study

Liu, Y., Sandmann, F. G., Barnard, R. C., Pearson, C. A., Pastore, R., Pebody, R., Flasche, S., & Jit, M. (n.d.).

Publication year

2022

Journal title

The Lancet Regional Health - Europe

Volume

12

10.1016/j.lanepe.2021.100267

Abstract

Abstract

Background: Countries in the World Health Organization (WHO) European Region differ in terms of the COVID-19 vaccine supply conditions. We evaluated the health and economic impact of different age-based vaccine prioritisation strategies across this demographically and socio-economically diverse region. Methods: We fitted age-specific compartmental models to the reported daily COVID-19 mortality in 2020 to inform the immunity level before vaccine roll-out. Models capture country-specific differences in population structures, contact patterns, epidemic history, life expectancy, and GDP per capita. We examined four strategies that prioritise: all adults (V+), younger (20-59 year-olds) followed by older adults (60+) (V20), older followed by younger adults (V60), and the oldest adults (75+) (V75) followed by incrementally younger age groups. We explored four roll-out scenarios (R1-4) — the slowest scenario (R1) reached 30% coverage by December 2022 and the fastest (R4) 80% by December 2021. Five decision-making metrics were summarised over 2021-22: mortality, morbidity, and losses in comorbidity-adjusted life expectancy, comorbidity- and quality-adjusted life years, and human capital. Six vaccine profiles were tested — the highest performing vaccine has 95% efficacy against both infection and disease, and the lowest 50% against diseases and 0% against infection. Findings: Of the 20 decision-making metrics and roll-out scenario combinations, the same optimal strategy applied to all countries in only one combination; V60 was more or similarly desirable than V75 in 19 combinations. Of the 38 countries with fitted models, 11-37 countries had variable optimal strategies by decision-making metrics or roll-out scenarios. There are greater benefits in prioritising older adults when roll-out is slow and when vaccine profiles are less favourable. Interpretation: The optimal age-based vaccine prioritisation strategies were sensitive to country characteristics, decision-making metrics, and roll-out speeds. A prioritisation strategy involving more age-based stages (V75) does not necessarily lead to better health and economic outcomes than targeting broad age groups (V60). Countries expecting a slow vaccine roll-out may particularly benefit from prioritising older adults.

Prevalence and Determinants of Vaginal Infection with Human Papillomavirus among Female University Students in Vietnam

van Trang, N., Prem, K., Toh, Z. Q., Ha, B. T., Lan, P. T., Tran, H. P., Pham, Q. D., van Khuu, N., Jit, M., Luu, D. T., Ly, L. T., Cao, V., Le-Ha, T. D., Bright, K., Garland, S. M., Anh, D. D., & Mulholland, K. (n.d.).

Publication year

2022

Journal title

In Vivo

Volume

36

Issue

1

Page(s)

241-250

10.21873/INVIVO.12697

Abstract

Abstract

Background/Aim: Cervical cancer is the second most common malignancy among women in Vietnam, but the country is yet to introduce a national human papillomavirus (HPV) vaccine programme targeted at adolescents. We determined HPV prevalence and HPV vaccine knowledge among female university students in Vietnam. Patients and Methods: We surveyed and screened 1,491 female university students in Hanoi, Hue, and Ho Chi Minh City for their sexual behaviours, HPV knowledge and low- and high-risk HPV infection. Results: The prevalence of any HPV infection and any high-risk HPV infection were 4.2% (95%CI=3.3%-5.4%) and 3.4% (95%CI=2.5%-4.4%), respectively. Being sexually active [adjusted prevalence ratio (aPR): 6.22; 95%CI=3.4-11.37] and having ever been pregnant (aPR: 4.82; 95%CI=1.93-12.04) were positively associated with high-risk HPV infection. Whilst 60% of participants had heard of HPV vaccine, only 4.6% had received the vaccine. Conclusion: The low HPV prevalence found in university students in Vietnam indicates that they can benefit from HPV vaccination, along with a well-designed HPV health promotion programme.

Prevalence and risk factors for human papillomavirus infection among female sex workers in Hanoi and Ho Chi Minh City, Viet Nam : a cross-sectional study

Pham, Q. D., Prem, K., Le, T. A., Trang, N. V., Jit, M., Nguyen, T. A., Cao, V., Le-Ha, T. D., Chu, M. T., Le, L. T., Toh, Z. Q., Brisson, M., Garland, S., Murray, G., Bright, K., Dang, D. A., Tran, H. P., & Mulholland, E. K. (n.d.).

Publication year

2022

Journal title

Western Pacific surveillance and response journal : WPSAR

Volume

13

Issue

4

10.5365/wpsar.2022.13.4.894

Abstract

Abstract

Objective: Female sex workers (FSWs) are at high risk of human papillomavirus (HPV) infections and cervical cancer due to their high number of sexual partners. The objectives of this study were to determine the prevalence of HPV and identify risk factors for high-risk HPV infection among FSWs in Hanoi and Ho Chi Minh City (HCMC), Viet Nam. Methods: A cross-sectional study was conducted in Hanoi and HCMC between December 2017 and May 2018. We surveyed and screened 699 FSWs aged ≥18 years for HPV infection and abnormal cytology. A multivariable modified Cox regression model was used to determine risk factors for high-risk HPV infection. Results: The overall prevalence of any HPV, high-risk HPV and HPV-16/18 infection in the 699 FSWs was 26.3%, 17.6% and 4.0%, respectively, and were similar in both cities. Multiple infections were identified in 127 participants (69.0%). HPV-52 was the most prevalent (7%), followed by HPV-58 (6%). Abnormal cytology was detected in 91 participants (13.0%). FSWs who are divorced (adjusted prevalence ratio [aPR]: 1.96, 95% confidence interval [CI]: 1.01–3.81), widowed (aPR: 3.26, 95% CI: 1.49–7.12) or living alone (aPR: 1.85, 95% CI: 1.01–3.39) were associated with a higher prevalence of high-risk HPV infection. Discussion: Almost one in five FSWs in Viet Nam are infected with high-risk HPV. This highlights the importance of prevention strategies such as HPV vaccination and screening in this high-risk group.

Quantifying the Acute Care Costs of Neonatal Bacterial Sepsis and Meningitis in Mozambique and South Africa

Aerts, C., Leahy, S., Mucasse, H., Lala, S., Bramugy, J., Tann, C. J., Madhi, S. A., Bardají, A., Bassat, Q., Dangor, Z., Lawn, J. E., Jit, M., & Procter, S. R. (n.d.).

Publication year

2022

Journal title

Clinical Infectious Diseases

Volume

74

Page(s)

S64-S69

10.1093/cid/ciab815

Abstract

Abstract

Background: Sepsis and meningitis are among the leading causes of neonatal deaths in sub-Saharan Africa (SSA). Neonatal sepsis caused ∼400 000 deaths globally in 2015, half occurring in Africa. Despite this, there are few published data on the acute costs of neonatal sepsis or meningitis, with none in SSA. Methods: We enrolled neonates admitted to 2 hospitals in South Africa and Mozambique between 16 April 2020 and 1 April 2021. In South Africa all cases were microbiologically confirmed, but in Mozambique both clinically suspected and microbiologically confirmed cases were included. Data were collected on healthcare resource use and length of stay, along with information on household expenditure and caregiving. We used unit costs of healthcare resources in local currencies to estimate healthcare provider costs per patient and costs per household. Results were converted to 2019 international dollars (I$). Results: We enrolled 11 neonates in Mozambique and 18 neonates in South Africa. Mean length of stay was 10 days (median, 9 [interquartile range {IQR}, 4-14) and 16 days (median, 15 [IQR, 13-18]), respectively. In Mozambique we estimated mean household costs of I$49.62 (median, 10.19 [IQR, 5.10-95.12]) and hospitalization costs of I$307.58 (median, 275.12 [IQR, 149.43-386.12]). In South Africa these costs were I$52.31 (median, 30.82 [IQR, 19.25-73.08]) and I$684.06 (median, 653.62 [IQR, 543.33-827.53]), respectively. Conclusions: We found substantial costs associated with acute neonatal bacterial (all-cause) sepsis and meningitis in SSA. Our estimates will inform economic evaluations of interventions to prevent neonatal invasive bacterial infections.

Rapid COVID-19 vaccine rollout : immense success but challenges ahead

Sandmann, F. G., & Jit, M. (n.d.).

Publication year

2022

Journal title

The Lancet Infectious Diseases

Volume

22

Issue

3

Page(s)

302-304

10.1016/S1473-3099(21)00616-2

Abstract

Abstract

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Regional-based within-year seasonal variations in influenza-related health outcomes across mainland China : a systematic review and spatio-temporal analysis

Diamond, C., Gong, H., Sun, F. Y., Liu, Y., Quilty, B. J., Jit, M., Yang, J., Yu, H., Edmunds, W. J., & Baguelin, M. (n.d.).

Publication year

2022

Journal title

BMC Medicine

Volume

20

Issue

1

10.1186/s12916-022-02269-5

Abstract

Abstract

Background: China experiences large variations in influenza seasonal activity. We aim to update and improve the current understanding of regional-based within-year variations of influenza activity across mainland China to provide evidence for the planning and optimisation of healthcare strategies. Methods: We conducted a systematic review and spatio-temporal meta-analysis to assess regional-based within-year variations of ILI outpatient consultation rates, influenza test positivity rates amongst both ILI outpatients and SARI inpatients, and influenza-associated excess mortality rates. We searched English and Chinese databases for articles reporting time-series data on the four influenza-related outcomes at the sub-national and sub-annual level. After synthesising the data, we reported on the mean monthly rate, epidemic onset, duration, peak and intensity. Results: We included 247 (7.7%) eligible studies in the analysis. We found within-year influenza patterns to vary across mainland China in relation to latitude and geographic location. High-latitude provinces were characterised by having short and intense annual winter epidemics, whilst most mid-latitude and low-latitude provinces experience semi-annual epidemics or year-round activity. Subtype activity varied across the country, with A/H1N1pdm09 and influenza B occurring predominantly in the winter, whereas A/H3N2 activity exhibited a latitudinal divide with high-latitude regions experiencing a winter peak, whilst mid and low-latitude regions experienced a summer epidemic. Epidemic onsets and peaks also varied, occurring first in the north and later in the southeast. We found positive associations between all influenza health outcomes. In addition, seasonal patterns at the prefecture and county-level broadly resembled their wider province. Conclusions: This is the first systematic review to simultaneously examine the seasonal variation of multiple influenza-related health outcomes at multiple spatial scales across mainland China. The seasonality information provided here has important implications for the planning and optimisation of immunisation programmes and healthcare provision, supporting the need for regional-based approaches to address variations in local epidemiology.

SARS-CoV-2 antibodies protect against reinfection for at least 6 months in a multicentre seroepidemiological workplace cohort

the CMMID COVID-19 working group, A., the SpaceX COVID-19 Cohort Collaborative, A., Finch, E., Lowe, R., Fischinger, S., de St Aubin, M., Siddiqui, S. M., Dayal, D., Loesche, M. A., Rhee, J., Beger, S., Hu, Y., Gluck, M. J., Mormann, B., Hasdianda, M. A., Musk, E. R., Alter, G., Menon, A. S., Nilles, E. J., … Procter, S. R. (n.d.).

Publication year

2022

Journal title

PLoS biology

Volume

20

Issue

2

10.1371/journal.pbio.3001531

Abstract

Abstract

Identifying the potential for Severe Acute Respiratory Syndrome : Coronavirus 2 (SARS-CoV-2) reinfection is crucial for understanding possible long-term epidemic dynamics. We analysed longitudinal PCR and serological testing data from a prospective cohort of 4,411 United States employees in 4 states between April 2020 and February 2021. We conducted a multivariable logistic regression investigating the association between baseline serological status and subsequent PCR test result in order to calculate an odds ratio for reinfection. We estimated an odds ratio for reinfection ranging from 0.14 (95% CI: 0.019 to 0.63) to 0.28 (95% CI: 0.05 to 1.1), implying that the presence of SARS-CoV-2 antibodies at baseline is associated with around 72% to 86% reduced odds of a subsequent PCR positive test based on our point estimates. This suggests that primary infection with SARS-CoV-2 provides protection against reinfection in the majority of individuals, at least over a 6-month time period. We also highlight 2 major sources of bias and uncertainty to be considered when estimating the relative risk of reinfection, confounders, and the choice of baseline time point and show how to account for both in reinfection analysis.

The allocation of COVID-19 vaccines and antivirals against emerging SARS-CoV-2 variants of concern in East Asia and Pacific region : A modelling study

Leung, K., Jit, M., Leung, G. M., & Wu, J. T. (n.d.).

Publication year

2022

Journal title

The Lancet Regional Health - Western Pacific

Volume

21

10.1016/j.lanwpc.2022.100389

Abstract

Abstract

Background: In view of emerging variants of concern (VOCs), we aimed to evaluate the impact of various allocation strategies of COVID-19 vaccines and antiviral such that the pandemic exit strategy could be tailored to risks and preferences of jurisdictions in the East Asia and Pacific region (EAP) to improve its efficiency and effectiveness. Methods: Vaccine efficacies were estimated from the titre distributions of 50% plaque reduction neutralization test (PRNT50), assuming that PRNT50 titres of primary vaccination decreased by 2-10 folds due to antibody waning and emergence of VOCs, and an additional dose of vaccine would increase PRNT50 titres by 3- or 9-fold. We then used an existing SARS-CoV-2 transmission model to assess the outcomes of vaccine allocation strategies with and without the use of antivirals for symptomatic patients in Japan, Hong Kong, and Vietnam. Findings: Increasing primary vaccination coverage was the most important contributing factor in reducing the total and peak number of COVID-19 hospitalisations, especially when population vaccine coverage or vaccine uptake among older adults was low. Providing antivirals to 50% of symptomatic infections only further reduced total and peak hospitalisations by 10-13%. The effectiveness of an additional dose of vaccine was highly dependent on the immune escape potential of VOCs and antibody waning, but less dependent on the boosting efficacy of the additional dose. Interpretation: Increasing primary vaccination coverage should be prioritised in the design of allocation strategies of COVID-19 vaccines and antivirals against emerging VOCs, such as Omicron, in the EAP region. Heterologous vaccination with any available vaccine as the additional dose could be considered when planning pandemic exit strategies tailored to the circumstances of EAP jurisdictions.

The contribution of hospital-acquired infections to the COVID-19 epidemic in England in the first half of 2020

ISARIC4C investigators, A., CMMID COVID-19 Working Group, A., Knight, G. M., Pham, T. M., Stimson, J., Funk, S., Jafari, Y., Pople, D., Evans, S., Yin, M., Brown, C. S., Bhattacharya, A., Hope, R., Semple, M. G., Abbott, S., Gimma, A., Gibbs, H. P., Abbas, K., Barnard, R. C., … Pearson, C. A. (n.d.).

Publication year

2022

Journal title

BMC Infectious Diseases

Volume

22

Issue

1

10.1186/s12879-022-07490-4

Abstract

Abstract

Background: SARS-CoV-2 is known to transmit in hospital settings, but the contribution of infections acquired in hospitals to the epidemic at a national scale is unknown. Methods: We used comprehensive national English datasets to determine the number of COVID-19 patients with identified hospital-acquired infections (with symptom onset > 7 days after admission and before discharge) in acute English hospitals up to August 2020. As patients may leave the hospital prior to detection of infection or have rapid symptom onset, we combined measures of the length of stay and the incubation period distribution to estimate how many hospital-acquired infections may have been missed. We used simulations to estimate the total number (identified and unidentified) of symptomatic hospital-acquired infections, as well as infections due to onward community transmission from missed hospital-acquired infections, to 31st July 2020. Results: In our dataset of hospitalised COVID-19 patients in acute English hospitals with a recorded symptom onset date (n = 65,028), 7% were classified as hospital-acquired. We estimated that only 30% (range across weeks and 200 simulations: 20–41%) of symptomatic hospital-acquired infections would be identified, with up to 15% (mean, 95% range over 200 simulations: 14.1–15.8%) of cases currently classified as community-acquired COVID-19 potentially linked to hospital transmission. We estimated that 26,600 (25,900 to 27,700) individuals acquired a symptomatic SARS-CoV-2 infection in an acute Trust in England before 31st July 2020, resulting in 15,900 (15,200–16,400) or 20.1% (19.2–20.7%) of all identified hospitalised COVID-19 cases. Conclusions: Transmission of SARS-CoV-2 to hospitalised patients likely caused approximately a fifth of identified cases of hospitalised COVID-19 in the “first wave” in England, but less than 1% of all infections in England. Using time to symptom onset from admission for inpatients as a detection method likely misses a substantial proportion (> 60%) of hospital-acquired infections.

The impact of COVID-19 vaccination in prisons in England and Wales : a metapopulation model

CMMID COVID-19 Working Group, A., McCarthy, C. V., O’Mara, O., van Leeuwen, E., Sherratt, K., Abbas, K., Wong, K. L., Atkins, K. E., Lowe, R., Meakin, S. R., Davies, N. G., Russell, T. W., O’Reilly, K., Hué, S., Finch, E., Villabona-Arenas, C. J., Edmunds, W. J., Jafari, Y., Tully, D. C., … Sandmann, F. (n.d.).

Publication year

2022

Journal title

BMC public health

Volume

22

Issue

1

10.1186/s12889-022-13219-4

Abstract

Abstract

Background: High incidence of cases and deaths due to coronavirus disease 2019 (COVID-19) have been reported in prisons worldwide. This study aimed to evaluate the impact of different COVID-19 vaccination strategies in epidemiologically semi-enclosed settings such as prisons, where staff interact regularly with those incarcerated and the wider community. Methods: We used a metapopulation transmission-dynamic model of a local prison in England and Wales. Two-dose vaccination strategies included no vaccination, vaccination of all individuals who are incarcerated and/or staff, and an age-based approach. Outcomes were quantified in terms of COVID-19-related symptomatic cases, losses in quality-adjusted life-years (QALYs), and deaths. Results: Compared to no vaccination, vaccinating all people living and working in prison reduced cases, QALY loss and deaths over a one-year period by 41%, 32% and 36% respectively. However, if vaccine introduction was delayed until the start of an outbreak, the impact was negligible. Vaccinating individuals who are incarcerated and staff over 50 years old averted one death for every 104 vaccination courses administered. All-staff-only strategies reduced cases by up to 5%. Increasing coverage from 30 to 90% among those who are incarcerated reduced cases by around 30 percentage points. Conclusions: The impact of vaccination in prison settings was highly dependent on early and rapid vaccine delivery. If administered to both those living and working in prison prior to an outbreak occurring, vaccines could substantially reduce COVID-19-related morbidity and mortality in prison settings.

Transmission dynamics of SARS-CoV-2 in a strictly-Orthodox Jewish community in the UK

CMMID COVID-19 Working Group, A., Waites, W., Pearson, C. A., Gaskell, K. M., House, T., Pellis, L., Johnson, M., Gould, V., Hunt, A., Stone, N. R., Kasstan, B., Chantler, T., Lal, S., Roberts, C. H., Goldblatt, D., Abbas, K., Abbott, S., Atkins, K. E., Barnard, R. C., … Medley, G. (n.d.).

Publication year

2022

Journal title

Scientific reports

Volume

12

Issue

1

10.1038/s41598-022-12517-6

Abstract

Abstract

Some social settings such as households and workplaces, have been identified as high risk for SARS-CoV-2 transmission. Identifying and quantifying the importance of these settings is critical for designing interventions. A tightly-knit religious community in the UK experienced a very large COVID-19 epidemic in 2020, reaching 64.3% seroprevalence within 10 months, and we surveyed this community both for serological status and individual-level attendance at particular settings. Using these data, and a network model of people and places represented as a stochastic graph rewriting system, we estimated the relative contribution of transmission in households, schools and religious institutions to the epidemic, and the relative risk of infection in each of these settings. All congregate settings were important for transmission, with some such as primary schools and places of worship having a higher share of transmission than others. We found that the model needed a higher general-community transmission rate for women (3.3-fold), and lower susceptibility to infection in children to recreate the observed serological data. The precise share of transmission in each place was related to assumptions about the internal structure of those places. Identification of key settings of transmission can allow public health interventions to be targeted at these locations.

Travel measures in the SARS-CoV-2 variant era need clear objectives

Kucharski, A. J., Jit, M., Logan, J. G., Cotten, M., Clifford, S., Quilty, B. J., Russell, T. W., Peeling, R. W., Antonio, M., & Heymann, D. L. (n.d.).

Publication year

2022

Journal title

The Lancet

Volume

399

Issue

10333

Page(s)

1367-1369

10.1016/S0140-6736(22)00366-X

Abstract

Abstract

~

Using high-resolution contact networks to evaluate SARS-CoV-2 transmission and control in large-scale multi-day events

Singapore CruiseSafe working group, A., CMMID COVID-19 Working Group, A., Pung, R., Firth, J. A., Spurgin, L. G., Chang, A., Kong, J., Wong, J., Jin, O. J., Selvaraj, D., Yong, D., Lang, J., Sivalingam, A., Procter, S. R., Flasche, S., Waites, W., Prem, K., Pearson, C. A., Gibbs, H. P., … Koltai, M. (n.d.).

Publication year

2022

Journal title

Nature communications

Volume

13

Issue

1

10.1038/s41467-022-29522-y

Abstract

Abstract

The emergence of highly transmissible SARS-CoV-2 variants has created a need to reassess the risk posed by increasing social contacts as countries resume pre-pandemic activities, particularly in the context of resuming large-scale events over multiple days. To examine how social contacts formed in different activity settings influences interventions required to control Delta variant outbreaks, we collected high-resolution data on contacts among passengers and crew on cruise ships and combined the data with network transmission models. We found passengers had a median of 20 (IQR 10–36) unique close contacts per day, and over 60% of their contact episodes were made in dining or sports areas where mask wearing is typically limited. In simulated outbreaks, we found that vaccination coverage and rapid antigen tests had a larger effect than mask mandates alone, indicating the importance of combined interventions against Delta to reduce event risk in the vaccine era.

WHO-led consensus statement on vaccine delivery costing : process, methods, and findings

Levin, A., Boonstoppel, L., Brenzel, L., Griffiths, U., Hutubessy, R., Jit, M., Mogasale, V., Pallas, S., Resch, S., Suharlim, C., & Yeung, K. H. (n.d.).

Publication year

2022

Journal title

BMC Medicine

Volume

20

Issue

1

10.1186/s12916-022-02278-4

Abstract

Abstract

Background: Differences in definitions and methodological approaches have hindered comparison and synthesis of economic evaluation results across multiple health domains, including immunization. At the request of the World Health Organization’s (WHO) Immunization and Vaccines-related Implementation Research Advisory Committee (IVIR-AC), WHO convened an ad hoc Vaccine Delivery Costing Working Group, comprising experts from eight organizations working in immunization costing, to address a lack of standardization and gaps in definitions and methodological guidance. The aim of the Working Group was to develop a consensus statement harmonizing terminology and principles and to formulate recommendations for vaccine delivery costing for decision making. This paper discusses the process, findings of the review, and recommendations in the Consensus Statement. Methods: The Working Group conducted several interviews, teleconferences, and one in-person meeting to identify groups working in vaccine delivery costing as well as existing guidance documents and costing tools, focusing on those for low- and middle-income country settings. They then reviewed the costing aims, perspectives, terms, methods, and principles in these documents. Consensus statement principles were drafted to align with the Global Health Cost Consortium costing guide as an agreed normative reference, and consensus definitions were drafted to reflect the predominant view across the documents reviewed. Results: The Working Group identified four major workstreams on vaccine delivery costing as well as nine guidance documents and eleven costing tools for immunization costing. They found that some terms and principles were commonly defined while others were specific to individual workstreams. Based on these findings and extensive consultation, recommendations to harmonize differences in terminology and principles were made. Conclusions: Use of standardized principles and definitions outlined in the Consensus Statement within the immunization delivery costing community of practice can facilitate interpretation of economic evidence by global, regional, and national decision makers. Improving methodological alignment and clarity in program costing of health services such as immunization is important to support evidence-based policies and optimal resource allocation. On the other hand, this review and Consensus Statement development process revealed the limitations of our ability to harmonize given that study designs will vary depending upon the policy question that is being addressed and the country context.

A cross-sectional analysis of meteorological factors and SARS-CoV-2 transmission in 409 cities across 26 countries

MCC 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

2021

Journal title

Nature communications

Volume

12

Issue

1

10.1038/s41467-021-25914-8

Abstract

Abstract

There 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.