scholarly journals Reassessing the evidence for universal school-age BCG vaccination in England and Wales: re-evaluating and updating a modelling study

BMJ Open ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. e031573
Author(s):  
Sam Abbott ◽  
Hannah Christensen ◽  
Ellen Brooks-Pollock
Keyword(s):  
Policy Change ◽  
Parameter Uncertainty ◽  
Incidence Rates ◽  
Parameter Estimates ◽  
School Age ◽  
England And Wales ◽  
Bcg Vaccination ◽  
Methodological Flaw ◽  
Notification Data ◽  
The Impact

ObjectivesIn 2005, England and Wales switched from universal BCG vaccination against tuberculosis (TB) disease for school-age children to targeted vaccination of neonates. We aimed to recreate and re-evaluate a previously published model, the results of which informed this policy change.DesignWe recreated an approach for estimating the impact of ending the BCG schools scheme, correcting a methodological flaw in the model, updating the model with parameter uncertainty and improving parameter estimates where possible. We investigated scenarios for the assumed annual decrease in TB incidence rates considered by the UK’s Joint Committee on Vaccination and Immunisation and explored alternative scenarios using notification data.SettingEngland and Wales.Outcome measuresThe number of vaccines needed to prevent a single notification and the average annual additional notifications caused by ending the policy change.ResultsThe previously published model was found to contain a methodological flaw and to be spuriously precise. It greatly underestimated the impact of ending school-age vaccination compared with our updated, corrected model. The updated model produced predictions with wide CIs when parameter uncertainty was included. Model estimates based on an assumption of an annual decrease in TB incidence rates of 1.9% were closest to those estimated using notification data. Using this assumption, we estimate that 1600 (2.5; 97.5% quantiles: 1300, 2000) vaccines would have been required to prevent a single notification in 2004.ConclusionsThe impact of ending the BCG schools scheme was found to be greater than previously thought when notification data were used. Our results highlight the importance of independent evaluations of modelling evidence, including uncertainty, and evaluating multiple scenarios when forecasting the impact of changes in vaccination policy.

scholarly journals Reassessing the Evidence for Universal School-age Bacillus Calmette Guerin (BCG) Vaccination in England and Wales

2019 ◽  
Author(s):  
Sam Abbott ◽  
Hannah Christensen ◽  
Ellen Brooks-Pollock
Keyword(s):  
Parameter Uncertainty ◽  
Incidence Rates ◽  
School Age Children ◽  
List Type ◽  
School Age ◽  
Bacillus Calmette Guerin ◽  
England And Wales ◽  
Bcg Vaccination ◽  
Notification Data ◽  
The Impact

AbstractBackgroundIn 2005, England and Wales switched from universal BCG vaccination against tuberculosis (TB) disease for school-age children to targeted vaccination of neonates. We assessed the quantitative evidence that informed this policy change.MethodsWe recreated a previous approach for estimating the impact of ending the BCG schools’ scheme in England and Wales, updating the model with parameter uncertainty. We investigated scenarios considered by the UK’s Joint Committee on Vaccination and Immunisation, and explored new approaches using notification data. We estimated the number of vaccines needed to prevent a single notification, and the average annual additional notifications caused by ending the BCG schools’ scheme.ResultsWe found a 1.9% annual decrease in TB incidence rates best matched notification data. We estimate that 1600 (2.5-97.5% Quantiles (Q): 1300 - 2100) vaccines would have been required to prevent a single notification in 2004. If the scheme had ended in 2001, 302 (2.5-97.5% Q: 238 - 369) additional annual notifications would have occurred compared to if the scheme had continued. If the scheme ended in 2016, 120 (2.5-97.5% Q: 88 - 155) additional annual notifications would have occurred.ConclusionsOur estimates of the impact of ending the BCG schools’ scheme were highly sensitive to the annual decrease in incidence rates. The impact of ending the BCG schools’ scheme was found to be greater than previously thought when parameter values were updated and notification data were used. Our results highlight the importance of including uncertainty when forecasting the impact of changes in vaccination policy.What is already known on this subjectTargeted Bacillus Calmette Guerin (BCG) vaccination against TB is recommended in low incidence countries over universal vaccination.The impact of replacing universal BCG vaccination in England and Wales with a targeted programme in 2005 was assessed under the assumption of static declines in TB rates.The BCG Guerin vaccine was shown to be effective in the UK born in England, regardless of the age at which it was given. School-age vaccination maybe more beneficial in this population than in other settings.What this study addsUsing notification data from England and Wales from 1973 to 2015, we estimate that the ending the BCG schools’ scheme likely resulted in more additional cases than was predicted.The inclusion of parameter uncertainty, and measurement error, allowed the uncertainty in the final estimates to be presented. Previously published estimates may have been spuriously precise.This study highlights the need for a more detailed evaluation of the 2005 change in BCG policy. In particular, the impact of including the introduction of targeted neonatal vaccination and capturing the long term, indirect, effects needs further study.

scholarly journals Estimating the effect of the 2005 change in BCG policy in England: a retrospective cohort study, 2000 to 2015

2019 ◽  
Vol 24 (49) ◽  
Author(s):  
Sam Abbott ◽  
Hannah Christensen ◽  
Nicky J. Welton ◽  
Ellen Brooks-Pollock
Keyword(s):  
High Risk ◽  
Labour Force ◽  
Demographic Data ◽  
Credible Interval ◽  
Incidence Rates ◽  
School Age Children ◽  
School Age ◽  
Bcg Vaccination ◽  
The Uk ◽  
The Impact

Background In 2005 in England, universal Bacillus Calmette–Guérin (BCG) vaccination of school-age children was replaced by targeted BCG vaccination of high-risk neonates. Aim Estimate the impact of the 2005 change in BCG policy on tuberculosis (TB) incidence rates in England. Methods We conducted an observational study by combining notifications from the Enhanced Tuberculosis Surveillance system, with demographic data from the Labour Force Survey to construct retrospective cohorts relevant to both the universal and targeted vaccination between 1 January 2000 and 31 December 2010. We then estimated incidence rates over a 5-year follow-up period and used regression modelling to estimate the impact of the change in policy on TB. Results In the non-United Kingdom (UK) born, we found evidence for an association between a reduction in incidence rates and the change in BCG policy (school-age incidence rate ratio (IRR): 0.74; 95% credible interval (CrI): 0.61 to 0.88 and neonatal IRR: 0.62; 95%CrI: 0.44 to 0.88). We found some evidence that the change in policy was associated with an increase in incidence rates in the UK born school-age population (IRR: 1.08; 95%CrI: 0.97 to 1.19) and weaker evidence of an association with a reduction in incidence rates in UK born neonates (IRR: 0.96; 95%CrI: 0.82 to 1.14). Overall, we found that the change in policy was associated with directly preventing 385 (95%CrI: −105 to 881) cases. Conclusions Withdrawing universal vaccination at school age and targeting vaccination towards high-risk neonates was associated with reduced incidence of TB. This was largely driven by reductions in the non-UK born with cases increasing in the UK born.

scholarly journals Estimating the effect of the 2005 change in BCG policy in England: A retrospective cohort study

2019 ◽  
Author(s):  
Sam Abbott ◽  
Hannah Christensen ◽  
Nicky Welton ◽  
Ellen Brooks-Pollock
Keyword(s):  
High Risk ◽  
Negative Binomial ◽  
Labour Force ◽  
Incidence Rates ◽  
School Age Children ◽  
List Type ◽  
School Age ◽  
Bcg Vaccination ◽  
The Uk ◽  
The Impact

ABSTRACTBackgroundIn 2005, England changed from universal Bacillus Calmette–Guérin (BCG) vaccination of school-age children to targeted BCG vaccination of high-risk children at birth.MethodsWe combined notification data from the Enhanced Tuberculosis Surveillance system, with demographic data from the Labour Force Survey to construct retrospective cohorts of individuals in England relevant to both the universal, and targeted vaccination programmes between Jan 1, 2000 and Dec 31, 2010. For each cohort, we estimated incidence rates over a 5 year follow-up period and used Poisson and Negative Binomial regression models in order to estimate the impact of the change in policy on TB.ResultsIn the non-UK born, we found evidence for an association between a reduction in incidence rates and the change in BCG policy (school-age IRR: 0.74 (95%CI 0.61, 0.88), neonatal IRR: 0.62 (95%CI 0.44, 0.88)). We found some evidence that the change in BCG policy was associated with a increase in incidence rates in the UK born school-age population (IRR: 1.08 (95%CI 0.97, 1.19)) and weaker evidence of an association with a reduction in incidence rates in UK born neonates (IRR: 0.96 (95%CI 0.82, 1.14)). Overall, we found that the change in BCG policy was associated with directly preventing 385 (95% CI −105, 881) TB cases.ConclusionsWithdrawing universal vaccination at school-age and targeting BCG vaccination towards high-risk neonates was associated with reduced incidence of TB in England. This was largely driven by reductions in the non-UK born. There was a slight increase in UK born school-age cases.Key MessagesThere is little existing literature on the impact of withdrawing universal school-age BCG vaccination and introducing high-risk neonatal BCG vaccination on TB incidence rates in the populations directly affected by the vaccination programmes.There was strong evidence that the change in policy was associated with a decrease in TB incidence rates in non-UK born neonates and school-age children. In the UK born individuals, there was some evidence that the change in policy was associated with an increase in TB incidence rates in those relevant to the universal school-age scheme, with little evidence of a decrease in incidence rates in those relevant to the high-risk neonatal vaccination scheme.Overall the change in vaccination policy was associated with preventing TB cases, mainly in the non-UK born.These results provide an important evaluation of the direct effects of both withdrawing and implementing a BCG vaccination programme in a low incidence, high income, country and are relevant to several other countries that have made similar changes to their vaccination programmes.

scholarly journals The impact of policy change on prisoner resettlement and community integration: A case of disproportionate response

2020 ◽  
pp. 026101832095756
Author(s):  
Christopher Kay
Keyword(s):  
Community Engagement ◽  
Policy Change ◽  
Community Integration ◽  
England And Wales ◽  
Early Release ◽  
New Policies ◽  
Desistance From Crime ◽  
The Impact ◽  
Prisoner Rehabilitation

The involvement of prisoners on license in the recent London Bridge and Streatham, London attacks have triggered a series of policies aiming to restrict community release. These aim to address not only the point at which prisoners in England and Wales are released, but also the level of engagement prisoners can have with the community before release. They have been introduced with little consultation of the available evidence and, seemingly, with little consideration of those who will be directly impacted as a result of their implementation. This commentary considers how announced changes in policy relating to the use of Release on Temporary Licence (ROTL) with prisoners, represent a response which is not only disproportionate to the scale of the problem but may also negatively impact upon prisoner rehabilitation. It draws upon evidence surrounding the impact of early release and evidence surrounding the practices which work to promote desistance from crime to highlight the flaws in these new policies, but also the importance of maintaining community engagement in the rehabilitation of people with convictions.

scholarly journals An evaluation and comparison of three commonly used statistical models for automatic detection of outbreaks in epidemiological data of communicable diseases

2005 ◽  
Vol 134 (4) ◽  
pp. 863-871 ◽  
Author(s):  
P. ROLFHAMRE ◽  
K. EKDAHL
Keyword(s):  
New Zealand ◽  
Statistical Models ◽  
Hepatitis A ◽  
Disease Outbreaks ◽  
Epidemiological Data ◽  
Average Sensitivity ◽  
England And Wales ◽  
Baseline Levels ◽  
Notification Data ◽  
The Impact

We evaluated three established statistical models for automated ‘early warnings’ of disease outbreaks; counted data Poisson CuSums (used in New Zealand), the England and Wales model (used in England and Wales) and SPOTv2 (used in Australia). In the evaluation we used national Swedish notification data from 1992 to 2003 on campylobacteriosis, hepatitis A and tularemia. The average sensitivity and positive predictive value for CuSums were 71 and 53%, for the England and Wales model 87 and 82% and for SPOTv2 95 and 49% respectively. The England and Wales model and the SPOTv2 model were superior to CuSums in our setting. Although, it was more difficult to rank the former two, we recommend the SPOTv2 model over the England and Wales model, mainly because of a better sensitivity. However, the impact of previous outbreaks on baseline levels was less in the England and Wales model. The CuSums model did not adjust for previous outbreaks.

scholarly journals A spatial model of COVID-19 transmission in England and Wales: early spread, peak timing and the impact of seasonality

2021 ◽  
Vol 376 (1829) ◽  
pp. 20200272
Author(s):  
Leon Danon ◽  
Ellen Brooks-Pollock ◽  
Mick Bailey ◽  
Matt Keeling
Keyword(s):  
Seasonal Changes ◽  
Capacity Planning ◽  
Census Data ◽  
Transmission Rate ◽  
Parameter Estimates ◽  
Peak Time ◽  
England And Wales ◽  
Minimal Impact ◽  
Starting Location ◽  
The Impact

An outbreak of a novel coronavirus was first reported in China on 31 December 2019. As of 9 February 2020, cases have been reported in 25 countries, including probable human-to-human transmission in England. We adapted an existing national-scale metapopulation model to capture the spread of COVID-19 in England and Wales. We used 2011 census data to inform population sizes and movements, together with parameter estimates from the outbreak in China. We predict that the epidemic will peak 126 to 147 days (approx. 4 months) after the start of person-to-person transmission in the absence of controls. Assuming biological parameters remain unchanged and transmission persists from February, we expect the peak to occur in June. Starting location and model stochasticity have a minimal impact on peak timing. However, realistic parameter uncertainty leads to peak time estimates ranging from 78 to 241 days following sustained transmission. Seasonal changes in transmission rate can substantially impact the timing and size of the epidemic. We provide initial estimates of the epidemic potential of COVID-19. These results can be refined with more precise parameters. Seasonal changes in transmission could shift the timing of the peak into winter, with important implications for healthcare capacity planning. This article is part of the theme issue ‘Modelling that shaped the early COVID-19 pandemic response in the UK.

scholarly journals 761. Age-Related Incidence of TB Infection Supporting Efficacy of BCG Vaccination

2018 ◽  
Vol 5 (suppl_1) ◽  
pp. S273-S274
Author(s):  
Eileen Sweeney ◽  
Darren Dahly ◽  
Nahed Seddiq ◽  
Mary Horgan ◽  
Dan Corcoran ◽  
...  
Keyword(s):  
Population Data ◽  
Incidence Rates ◽  
Local Health ◽  
Spatial Scan Statistic ◽  
Immunization Policy ◽  
Bcg Vaccination ◽  
Age Related ◽  
Geographical Regions ◽  
Small Area Level ◽  
The Impact

Abstract Background Mycobacterium tuberculosis (MTB) is a major, and potentially preventable, cause of morbidity and mortality worldwide. Bacillus Calmette-Guerin (BCG) remains the only licensed vaccine for TB, and while efficacy has been demonstrated in some populations, many uncertainties remain. Three BCG vaccination policies were implemented across bordering geographical regions in the South West of Ireland from 1972; neonatal vaccination (vaccinated region-a), vaccination of children aged 10–12 years (vaccinated region-b) and no vaccination (unvaccinated region-c). The aim of this study was to investigate the impact of BCG vaccination on incidence of MTB during the study period. Methods Surveillance data were used to identify all M. tuberculosis complex (MTC) isolates from 2003 to 2016. Residential addresses for each case were geocoded using the Google Maps API. Case locations were spatially linked to 2011 census population data and to Local Health Offices (LHO) BCG coverage data for study regions a–c. The 13-year incidence of TB was calculated assuming a steady-state population. Using SatScan (v9.4.4), spatial clusters were identified at the small area level with the spatial scan statistic based on the discrete Poisson probability distribution. Results Of 638 MTC infections identified (621 MTB, 16 M. bovis, 1 M. africanum), 510 occurred in study regions a–c (median age 42 years (4 months–94 years), 65% male and 66% Irish born). The incidence of MTB was higher in the unvaccinated population, region-c 132/100,000 (95% CI 116–150) vs. vaccinated region-a 56/100,000 (95% CI 45–69) and region-b 44/100,000 (95% CI 29–63). A single high-risk cluster of 138 cases within a population of 46,000 was identified in unvaccinated region-c (relative risk 4.94 (95% CI 4–6). The year-on-year incidence rates in the 20- to 35-year-old age range suggested a decreasing risk consistent with a beneficial impact of vaccination policies. Conclusion Prevention and treatment of TB remains a significant challenge worldwide. Our study demonstrates significant differences in incidence of MTC infection in demographically similar populations based on BCG immunization policy and thus further supports efficacy of BCG for prevention of tuberculosis infection. Disclosures All authors: No reported disclosures.

The Impact of Missing and Error-Prone Auxiliary Information on Sparse-Matrix Sub-Population Parameter Estimates

Methodology ◽  
2015 ◽  
Vol 11 (3) ◽  
pp. 89-99 ◽  
Author(s):  
Leslie Rutkowski ◽  
Yan Zhou
Keyword(s):  
Sparse Matrix ◽  
Small Body ◽  
Auxiliary Information ◽  
Poor Quality ◽  
Quality Data ◽  
Estimation Methods ◽  
Parameter Estimates ◽  
Population Parameter ◽  
Conditioning Model ◽  
The Impact

Abstract. Given a consistent interest in comparing achievement across sub-populations in international assessments such as TIMSS, PIRLS, and PISA, it is critical that sub-population achievement is estimated reliably and with sufficient precision. As such, we systematically examine the limitations to current estimation methods used by these programs. Using a simulation study along with empirical results from the 2007 cycle of TIMSS, we show that a combination of missing and misclassified data in the conditioning model induces biases in sub-population achievement estimates, the magnitude and degree to which can be readily explained by data quality. Importantly, estimated biases in sub-population achievement are limited to the conditioning variable with poor-quality data while other sub-population achievement estimates are unaffected. Findings are generally in line with theory on missing and error-prone covariates. The current research adds to a small body of literature that has noted some of the limitations to sub-population estimation.

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