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1.
The Lancet Regional Health - Europe ; : 100381, 2022.
Article in English | ScienceDirect | ID: covidwho-1783621

ABSTRACT

Summary Background In settings where the COVID-19 vaccine supply is constrained, extending the intervals between the first and second doses of the COVID-19 vaccine may allow more people receive their first doses earlier. Our aim is to estimate the health impact of COVID-19 vaccination alongside benefit-risk assessment of different dosing intervals in 13 middle-income countries (MICs) of Europe. Methods We fitted a dynamic transmission model to country-level daily reported COVID-19 mortality in 13 MICs in Europe (Albania, Armenia, Azerbaijan, Belarus, Bosnia and Herzegovina, Bulgaria, Georgia, Republic of Moldova, Russian Federation, Serbia, North Macedonia, Turkey, and Ukraine). A vaccine product with characteristics similar to those of the Oxford/AstraZeneca COVID-19 (AZD1222) vaccine was used in the base case scenario and was complemented by sensitivity analyses around efficacies similar to other COVID-19 vaccines. Both fixed dosing intervals at 4, 8, 12, 16, and 20 weeks and dose-specific intervals that prioritise specific doses for certain age groups were tested. Optimal intervals minimise COVID-19 mortality between March 2021 and December 2022. We incorporated the emergence of variants of concern (VOCs) into the model and conducted a benefit-risk assessment to quantify the tradeoff between health benefits versus adverse events following immunisation. Findings In all countries modelled, optimal strategies are those that prioritise the first doses among older adults (60+ years) or adults (20+ years), which lead to dosing intervals longer than six months. In comparison, a four-week fixed dosing interval may incur 10.1% [range: 4.3% - 19.0%;n = 13 (countries)] more deaths. The rapid waning of the immunity induced by the first dose (i.e. with means ranging 60-120 days as opposed to 360 days in the base case) resulted in shorter optimal dosing intervals of 8-20 weeks. Benefit-risk ratios were the highest for fixed dosing intervals of 8-12 weeks. Interpretation We infer that longer dosing intervals of over six months could reduce COVID-19 mortality in MICs of Europe. Certain parameters, such as rapid waning of first-dose induced immunity and increased immune escape through the emergence of VOCs, could significantly shorten the optimal dosing intervals. Funding World Health Organization.

2.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-331766

ABSTRACT

Background Before the availability of vaccines, countries largely relied on mobility restriction and testing to mitigate the COVID-19 pandemic. Our aim is to assess the combined impact of mobility restriction, testing, and vaccination on the COVID-19 pandemic in India. Methods We conducted a multiple regression analysis to assess the impact of mobility, testing, and vaccination on COVID-19 incidence between April 28, 2021 to November 24, 2021 using data from Our World in Data and Google Mobility Report. The 7-day moving average was applied to offset the daily fluctuations in the mobility and testing. Each independent variable was lagged to construct a temporal relationship, and waning vaccination efficacy was taken into consideration. We performed additional analysis for three time periods between March 28, 2020 to November 24, 2021 (1 st March 28, 2020 ∼ October 7, 2020, 2 nd October 8, 2020 ∼ April 27, 2021, 3 rd April 28, 2021 ∼ November 24, 2021) to examine potential heterogeneity over time. Results Mobility (0.041, 95% CI: 0.033 to 0.048), testing (-0.008, 95% CI: -0.015 to -0.001), and vaccination (quadratic term: 0.004, 95% CI: 0.003 to 0.005, linear term: -0.130, 95% CI: -0.161 to -0.099) were all associated with COVID-19 incidence. For vaccination rate, the decrease of number of cases demonstrated a U-shaped curve, while mobility showed a positive association and testing showed an inverse association with COVID-19 incidence. Mobility restriction was effective during all three periods – March 28, 2020 to November 24, 2021 (0.009, 0.048, and 0.026 respectively). Testing was effective during the second and third period – October 8, 2020 to November 24, 2021 (-0.036, and -0.006 respectively). Conclusion Mobility restriction and testing were effective even in the presence of vaccination. This shows the positive value of mobility restrictions, testing, and vaccination from the health system perspective on COVID-19 prevention and control, especially with continual emergence of variants in India and globally. At the same time, this health system gain must be balanced with the challenges in the delivery of non-COVID health services and broader socio-economic impact in deciding the prolonged continuance of mobility restriction.

3.
SSRN; 2022.
Preprint in English | SSRN | ID: ppcovidwho-331765

ABSTRACT

Background: Before the availability of vaccines to control the COVID-19 pandemic, countries largely relied on mobility restriction and testing policies to mitigate the pandemic. There is uncertainty in the combined impact of mobility restriction, testing policies, and vaccination on the pandemic in different countries. Our aim is to assess the impact of mobility restriction, testing, and vaccination on the COVID-19 pandemic in India. Methods: We collected data on COVID-19 incidence, testing, and vaccination in India from Our World in Data, and mobility data from Google Mobility Report. To assess the combined effects of mobility restriction, testing policies, and vaccination on COVID-19 incidence, we conducted multiple regression analysis for the time period between April 28, 2021 to November 24, 2021. The 7-day moving average was applied to offset the daily fluctuations in the mobility and testing. Each independent variable was lagged to construct a temporal relationship, and waning vaccination efficacy was taken into consideration. We performed additional analysis for three time periods between March 28, 2020 to November 24, 2021 (1st period: March 28, 2020 ~ October 7, 2020, 2nd period: October 8, 2020 ~ April 27, 2021, 3rd period: April 28, 2021 ~ November 24, 2021) to examine potential heterogeneity of the results over time. Results: Mobility (0.041, 95% CI: 0.033 to 0.048), testing (-0.008, 95% CI: -0.015 to -0.001), and vaccination (quadratic term: 0.004, 95% CI: 0.003 to 0.005, linear term: -0.130, 95% CI: -0.161 to -0.099) were all associated with COVID-19 incidence. For vaccination rate, the decrease of number of cases demonstrated a U-shaped curve, while mobility showed positive association and testing showed inverse association with COVID-19 incidence. Mobility restriction was effective during all three periods – March 28, 2020 to November 24, 2021 (0.009, 0.048, and 0.026 respectively). Testing was effective during the second and third period – October 8, 2020 to November 24, 2021 (-0.036, and -0.006 respectively). Implications: We infer that mobility restriction and testing were effective interventions even in the presence of vaccination, while the effects changed over time. While this shows the positive value of mobility restrictions, testing, and vaccination from the health system perspective on COVID-19 prevention and control, especially with continual emergence of variants of concern in India and globally, this health system gain must be balanced with the challenges in the delivery of non-COVID health services and broader socio-economic impact on the society to decide for or against sustaining the mobility restrictions for a prolonged period of time.

4.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-331212

ABSTRACT

Background Evidence to date has shown that inequality in health, and vaccine coverage in particular, can have ramifications to wider society. However, whilst individual studies have sought to characterise these heterogeneities in immunisation coverage at national level, few have taken a broad and quantitative view of the contributing factors to heterogeneity in vaccine coverage and impact. This systematic review aims to highlight these geographic, demographic, and sociodemographic characteristics through a qualitative and quantitative approach, vital to prioritise and optimise vaccination policies. Methods A systematic review of two databases (PubMed and Web of Science) was undertaken using Medical Subject Headings (MeSH) and keywords to identify studies examining factors on vaccine inequality and heterogeneity in vaccine coverage. Inclusion criteria were applied independently by two researchers. Studies including data on key characteristics of interest were further analysed through a meta-analysis to produce a pooled estimate of the risk ratio using a random effects model for that characteristic. Results One hundred and eight studies were included in this review. We found that inequalities in wealth, education, and geographic access can affect vaccine impact and vaccine dropout. We estimated those living in rural areas were not significantly different in terms of full vaccination status compared to urban areas but noted considerable heterogeneity between countries. We found that females were 3% (95%CI[1%, 5%]) less likely to be fully vaccinated than males. Additionally, we estimated that children whose mothers had no formal education were 28% (95%CI[18%,47%]) less likely to be fully vaccinated than those whose mother had primary level, or above, education. Finally, we found that individuals in the poorest wealth quintile were 27% (95%CI [16%,37%]) less likely to be fully vaccinated than those in the richest. Conclusions We found a nuanced picture of inequality in vaccine coverage and access with wealth disparity dominating, and likely driving, other disparities. This review highlights the complex landscape of inequity and further need to design vaccination strategies targeting missed subgroups to improve and recover vaccination coverage following the COVID-19 pandemic. Registration Prospero CRD42021261927

5.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-296758

ABSTRACT

Background: The COVID-19 pandemic had enormous impacts on human society. There were similarities and differences in the public health and social measures taken by countries, and comparative analysis facilitates cross-country learning of contextual practices and sharing lessons to mitigate the COVID-19 pandemic impact. We aim to conduct a situational analysis of the public health and social measures to mitigate the health and economic impact of the COVID-19 pandemic in Turkey, Egypt, Ukraine, Kazakhstan, and Poland during 2020-2021. Methods We conducted a situational analysis of the COVID-19 pandemic response in Turkey, Egypt, Ukraine, Kazakhstan, and Poland from the perspectives of the health system and health finance, national coordination, surveillance, testing capacity, health infrastructure, healthcare workforce, medical supply, physical distancing and non-pharmaceutical interventions, health communication, impact on non-COVID-19 health services, impact on the economy, education, gender and civil liberties, and COVID-19 vaccination. Results Since the onset of the COVID-19 pandemic, Turkey, Egypt, Ukraine, Kazakhstan, and Poland have expanded COVID-19 testing and treatment capacity over time. However, they faced a shortage of healthcare workforce and medical supplies. They took population-based quarantine measures rather than individual-based isolation measures, which significantly burdened their economies and disrupted education. The unemployment rate increased, and economic growth stagnated. Economic stimulus policy was accompanied by high inflation. Despite the effort to sustain essential health services, healthcare access declined. Schools were closed for 5-11 months. Gender inequality was aggravated in Turkey and Ukraine, and an issue was raised for balancing public health measures and civil liberties in Egypt and Poland. Digital technologies played an important role in maintaining routine healthcare, education, and public health communication. Conclusions The COVID-19 pandemic has exposed weaknesses in healthcare systems in emerging countries of Turkey, Egypt, Ukraine, Kazakhstan, and Poland, and highlighted the intricate link between health and economy. Individual-level testing, isolation, and contact tracing are effective public health interventions in mitigating the health and economic impact of the COVID-19 pandemic in comparison to population-level measures of lockdowns. Investment in health, including digital health and communication, is essential to minimize the impact of the pandemic and for more equitable and sustainable development beyond the pandemic.

6.
BMC Med ; 19(1): 198, 2021 08 12.
Article in English | MEDLINE | ID: covidwho-1571757

ABSTRACT

BACKGROUND: The COVID-19 pandemic has disrupted the delivery of immunisation services globally. Many countries have postponed vaccination campaigns out of concern about infection risks to the staff delivering vaccination, the children being vaccinated, and their families. The World Health Organization recommends considering both the benefit of preventive campaigns and the risk of SARS-CoV-2 transmission when making decisions about campaigns during COVID-19 outbreaks, but there has been little quantification of the risks. METHODS: We modelled excess SARS-CoV-2 infection risk to vaccinators, vaccinees, and their caregivers resulting from vaccination campaigns delivered during a COVID-19 epidemic. Our model used population age structure and contact patterns from three exemplar countries (Burkina Faso, Ethiopia, and Brazil). It combined an existing compartmental transmission model of an underlying COVID-19 epidemic with a Reed-Frost model of SARS-CoV-2 infection risk to vaccinators and vaccinees. We explored how excess risk depends on key parameters governing SARS-CoV-2 transmissibility, and aspects of campaign delivery such as campaign duration, number of vaccinations, and effectiveness of personal protective equipment (PPE) and symptomatic screening. RESULTS: Infection risks differ considerably depending on the circumstances in which vaccination campaigns are conducted. A campaign conducted at the peak of a SARS-CoV-2 epidemic with high prevalence and without special infection mitigation measures could increase absolute infection risk by 32 to 45% for vaccinators and 0.3 to 0.5% for vaccinees and caregivers. However, these risks could be reduced to 3.6 to 5.3% and 0.1 to 0.2% respectively by use of PPE that reduces transmission by 90% (as might be achieved with N95 respirators or high-quality surgical masks) and symptomatic screening. CONCLUSIONS: SARS-CoV-2 infection risks to vaccinators, vaccinees, and caregivers during vaccination campaigns can be greatly reduced by adequate PPE, symptomatic screening, and appropriate campaign timing. Our results support the use of adequate risk mitigation measures for vaccination campaigns held during SARS-CoV-2 epidemics, rather than cancelling them entirely.


Subject(s)
COVID-19/prevention & control , Disease Outbreaks/prevention & control , Health Personnel , Immunization Programs/organization & administration , SARS-CoV-2 , Vaccination , Brazil , Burkina Faso , COVID-19/epidemiology , Child , Ethiopia , Female , Humans , Male , Pandemics , Personal Protective Equipment
7.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-293018

ABSTRACT

Background: In settings where the COVID-19 vaccine supply is constrained, extending the intervals between the first and second doses of the COVID-19 vaccine could let more people receive their first doses earlier. Our aim is to estimate the health impact of COVID-19 vaccination alongside benefit-risk assessment of different dosing intervals for low- and middle-income countries of Europe. Methods: We fitted a dynamic transmission model to country-level daily reported COVID-19 mortality in 13 low- and middle-income countries in the World Health Organization European Region (Albania, Armenia, Azerbaijan, Belarus, Bosnia and Herzegovina, Bulgaria, Georgia, Republic of Moldova, Russian Federation, Serbia, North Macedonia, Turkey, and Ukraine). A vaccine product with characteristics similar to the Oxford/AstraZeneca COVID-19 (AZD1222) vaccine was used in the base case scenario and was complemented by sensitivity analyses around efficacies related to other COVID-19 vaccines. Both fixed dosing intervals at 4, 8, 12, 16, and 20 weeks and dose-specific intervals that prioritise specific doses for certain age groups were tested. Optimal intervals minimise COVID-19 mortality between March 2021 and December 2022. We incorporated the emergence of variants of concern into the model, and also conducted a benefit-risk assessment to quantify the trade-off between health benefits versus adverse events following immunisation. Findings: In 12 of the 13 countries, optimal strategies are those that prioritise the first doses among older adults (60+ years) or adults (20-59 years). These strategies lead to dosing intervals longer than six months. In comparison, a four-week fixed dosing interval may incur 10.2% [range: 4.0% - 22.5%;n = 13 (countries)] more deaths. There is generally a negative association between dosing interval and COVID-19 mortality within the range we investigated. Assuming a shorter first dose waning duration of 120 days, as opposed to 360 days in the base case, led to shorter optimal dosing intervals of 8-12 weeks. Benefit-risk ratios were the highest for fixed dosing intervals of 8-12 weeks. Interpretation: We infer that longer dosing intervals of over six months, which are substantially longer than the current label recommendation for most vaccine products, could reduce COVID-19 mortality in low- and middle-income countries of WHO/Europe. Certain vaccine features, such as fast waning of first doses, significantly shorten the optimal dosing intervals.

8.
BMC Med ; 19(1): 281, 2021 11 17.
Article in English | MEDLINE | ID: covidwho-1523309

ABSTRACT

BACKGROUND: Model-based estimates of measles burden and the impact of measles-containing vaccine (MCV) are crucial for global health priority setting. Recently, evidence from systematic reviews and database analyses have improved our understanding of key determinants of MCV impact. We explore how representations of these determinants affect model-based estimation of vaccination impact in ten countries with the highest measles burden. METHODS: Using Dynamic Measles Immunisation Calculation Engine (DynaMICE), we modelled the effect of evidence updates for five determinants of MCV impact: case-fatality risk, contact patterns, age-dependent vaccine efficacy, the delivery of supplementary immunisation activities (SIAs) to zero-dose children, and the basic reproduction number. We assessed the incremental vaccination impact of the first (MCV1) and second (MCV2) doses of routine immunisation and SIAs, using metrics of total vaccine-averted cases, deaths, and disability-adjusted life years (DALYs) over 2000-2050. We also conducted a scenario capturing the effect of COVID-19 related disruptions on measles burden and vaccination impact. RESULTS: Incorporated with the updated data sources, DynaMICE projected 253 million measles cases, 3.8 million deaths and 233 million DALYs incurred over 2000-2050 in the ten high-burden countries when MCV1, MCV2, and SIA doses were implemented. Compared to no vaccination, MCV1 contributed to 66% reduction in cumulative measles cases, while MCV2 and SIAs reduced this further to 90%. Among the updated determinants, shifting from fixed to linearly-varying vaccine efficacy by age and from static to time-varying case-fatality risks had the biggest effect on MCV impact. While varying the basic reproduction number showed a limited effect, updates on the other four determinants together resulted in an overall reduction of vaccination impact by 0.58%, 26.2%, and 26.7% for cases, deaths, and DALYs averted, respectively. COVID-19 related disruptions to measles vaccination are not likely to change the influence of these determinants on MCV impact, but may lead to a 3% increase in cases over 2000-2050. CONCLUSIONS: Incorporating updated evidence particularly on vaccine efficacy and case-fatality risk reduces estimates of vaccination impact moderately, but its overall impact remains considerable. High MCV coverage through both routine immunisation and SIAs remains essential for achieving and maintaining low incidence in high measles burden settings.


Subject(s)
COVID-19 , Measles , Child , Humans , Immunization Programs , Infant , Measles/epidemiology , Measles/prevention & control , SARS-CoV-2 , Vaccination
9.
10.
Elife ; 102021 07 13.
Article in English | MEDLINE | ID: covidwho-1308531

ABSTRACT

Background: Vaccination is one of the most effective public health interventions. We investigate the impact of vaccination activities for Haemophilus influenzae type b, hepatitis B, human papillomavirus, Japanese encephalitis, measles, Neisseria meningitidis serogroup A, rotavirus, rubella, Streptococcus pneumoniae, and yellow fever over the years 2000-2030 across 112 countries. Methods: Twenty-one mathematical models estimated disease burden using standardised demographic and immunisation data. Impact was attributed to the year of vaccination through vaccine-activity-stratified impact ratios. Results: We estimate 97 (95%CrI[80, 120]) million deaths would be averted due to vaccination activities over 2000-2030, with 50 (95%CrI[41, 62]) million deaths averted by activities between 2000 and 2019. For children under-5 born between 2000 and 2030, we estimate 52 (95%CrI[41, 69]) million more deaths would occur over their lifetimes without vaccination against these diseases. Conclusions: This study represents the largest assessment of vaccine impact before COVID-19-related disruptions and provides motivation for sustaining and improving global vaccination coverage in the future. Funding: VIMC is jointly funded by Gavi, the Vaccine Alliance, and the Bill and Melinda Gates Foundation (BMGF) (BMGF grant number: OPP1157270 / INV-009125). Funding from Gavi is channelled via VIMC to the Consortium's modelling groups (VIMC-funded institutions represented in this paper: Imperial College London, London School of Hygiene and Tropical Medicine, Oxford University Clinical Research Unit, Public Health England, Johns Hopkins University, The Pennsylvania State University, Center for Disease Analysis Foundation, Kaiser Permanente Washington, University of Cambridge, University of Notre Dame, Harvard University, Conservatoire National des Arts et Métiers, Emory University, National University of Singapore). Funding from BMGF was used for salaries of the Consortium secretariat (authors represented here: TBH, MJ, XL, SE-L, JT, KW, NMF, KAMG); and channelled via VIMC for travel and subsistence costs of all Consortium members (all authors). We also acknowledge funding from the UK Medical Research Council and Department for International Development, which supported aspects of VIMC's work (MRC grant number: MR/R015600/1).JHH acknowledges funding from National Science Foundation Graduate Research Fellowship; Richard and Peggy Notebaert Premier Fellowship from the University of Notre Dame. BAL acknowledges funding from NIH/NIGMS (grant number R01 GM124280) and NIH/NIAID (grant number R01 AI112970). The Lives Saved Tool (LiST) receives funding support from the Bill and Melinda Gates Foundation.This paper was compiled by all coauthors, including two coauthors from Gavi. Other funders had no role in study design, data collection, data analysis, data interpretation, or writing of the report. All authors had full access to all the data in the study and had final responsibility for the decision to submit for publication.


Subject(s)
Bacterial Infections/prevention & control , Bacterial Vaccines/therapeutic use , COVID-19 , Global Health , Models, Biological , SARS-CoV-2 , Bacterial Infections/epidemiology , Humans
11.
Elife ; 102021 06 24.
Article in English | MEDLINE | ID: covidwho-1285537

ABSTRACT

Background: Childhood immunisation services have been disrupted by the COVID-19 pandemic. WHO recommends considering outbreak risk using epidemiological criteria when deciding whether to conduct preventive vaccination campaigns during the pandemic. Methods: We used two to three models per infection to estimate the health impact of 50% reduced routine vaccination coverage in 2020 and delay of campaign vaccination from 2020 to 2021 for measles vaccination in Bangladesh, Chad, Ethiopia, Kenya, Nigeria, and South Sudan, for meningococcal A vaccination in Burkina Faso, Chad, Niger, and Nigeria, and for yellow fever vaccination in the Democratic Republic of Congo, Ghana, and Nigeria. Our counterfactual comparative scenario was sustaining immunisation services at coverage projections made prior to COVID-19 (i.e. without any disruption). Results: Reduced routine vaccination coverage in 2020 without catch-up vaccination may lead to an increase in measles and yellow fever disease burden in the modelled countries. Delaying planned campaigns in Ethiopia and Nigeria by a year may significantly increase the risk of measles outbreaks (both countries did complete their supplementary immunisation activities (SIAs) planned for 2020). For yellow fever vaccination, delay in campaigns leads to a potential disease burden rise of >1 death per 100,000 people per year until the campaigns are implemented. For meningococcal A vaccination, short-term disruptions in 2020 are unlikely to have a significant impact due to the persistence of direct and indirect benefits from past introductory campaigns of the 1- to 29-year-old population, bolstered by inclusion of the vaccine into the routine immunisation schedule accompanied by further catch-up campaigns. Conclusions: The impact of COVID-19-related disruption to vaccination programs varies between infections and countries. Planning and implementation of campaigns should consider country and infection-specific epidemiological factors and local immunity gaps worsened by the COVID-19 pandemic when prioritising vaccines and strategies for catch-up vaccination. Funding: Bill and Melinda Gates Foundation and Gavi, the Vaccine Alliance.


Subject(s)
COVID-19/epidemiology , Immunization Programs/statistics & numerical data , Measles/prevention & control , Meningococcal Infections/prevention & control , Yellow Fever/prevention & control , Adolescent , Adult , Africa/epidemiology , Bangladesh/epidemiology , Child , Child, Preschool , Disease Outbreaks , Humans , Immunization Programs/methods , Infant , Measles/epidemiology , Measles Vaccine/therapeutic use , Meningococcal Infections/epidemiology , Meningococcal Vaccines/therapeutic use , Pandemics , Risk Assessment , SARS-CoV-2 , Vaccination/statistics & numerical data , Yellow Fever/epidemiology , Yellow Fever Vaccine/therapeutic use , Young Adult
12.
Lancet Glob Health ; 9(3): e251, 2021 03.
Article in English | MEDLINE | ID: covidwho-1149603
13.
Lancet Glob Health ; 8(10): e1264-e1272, 2020 10.
Article in English | MEDLINE | ID: covidwho-654153

ABSTRACT

BACKGROUND: National immunisation programmes globally are at risk of suspension due to the severe health system constraints and physical distancing measures in place to mitigate the ongoing COVID-19 pandemic. We aimed to compare the health benefits of sustaining routine childhood immunisation in Africa with the risk of acquiring severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection through visiting routine vaccination service delivery points. METHODS: We considered a high-impact scenario and a low-impact scenario to approximate the child deaths that could be caused by immunisation coverage reductions during COVID-19 outbreaks. In the high-impact scenario, we used previously reported country-specific child mortality impact estimates of childhood immunisation for diphtheria, tetanus, pertussis, hepatitis B, Haemophilus influenzae type b, Streptococcus pneumoniae, rotavirus, measles, meningitis A, rubella, and yellow fever to approximate the future deaths averted before 5 years of age by routine childhood vaccination during a 6-month COVID-19 risk period without catch-up campaigns. In the low-impact scenario, we approximated the health benefits of sustaining routine childhood immunisation on only the child deaths averted from measles outbreaks during the COVID-19 risk period. We assumed that contact-reducing interventions flattened the outbreak curve during the COVID-19 risk period, that 60% of the population will have been infected by the end of that period, that children can be infected by either vaccinators or during transport, and that upon child infection the whole household will be infected. Country-specific household age structure estimates and age-dependent infection-fatality rates were applied to calculate the number of deaths attributable to the vaccination clinic visits. We present benefit-risk ratios for routine childhood immunisation, with 95% uncertainty intervals (UIs) from a probabilistic sensitivity analysis. FINDINGS: In the high-impact scenario, for every one excess COVID-19 death attributable to SARS-CoV-2 infections acquired during routine vaccination clinic visits, 84 (95% UI 14-267) deaths in children could be prevented by sustaining routine childhood immunisation in Africa. The benefit-risk ratio for the vaccinated children is 85 000 (4900-546 000), for their siblings (<20 years) is 75 000 (4400-483 000), for their parents or adult carers (aged 20-60 years) is 769 (148-2700), and for older adults (>60 years) is 96 (14-307). In the low-impact scenario that approximates the health benefits to only the child deaths averted from measles outbreaks, the benefit-risk ratio to the households of vaccinated children is 3 (0-10); if the risk to only the vaccinated children is considered, the benefit-risk ratio is 3000 (182-21 000). INTERPRETATION: The deaths prevented by sustaining routine childhood immunisation in Africa outweigh the excess risk of COVID-19 deaths associated with vaccination clinic visits, especially for the vaccinated children. Routine childhood immunisation should be sustained in Africa as much as possible, while considering other factors such as logistical constraints, staff shortages, and reallocation of resources during the COVID-19 pandemic. FUNDING: Gavi, the Vaccine Alliance; Bill & Melinda Gates Foundation.


Subject(s)
Coronavirus Infections/epidemiology , Cross Infection/epidemiology , Pandemics , Pneumonia, Viral/epidemiology , Vaccine-Preventable Diseases/prevention & control , Vaccines/administration & dosage , Africa/epidemiology , Ambulatory Care , COVID-19 , Child, Preschool , Coronavirus Infections/mortality , Coronavirus Infections/transmission , Cross Infection/mortality , Humans , Immunization Programs , Immunization Schedule , Infant , Pneumonia, Viral/mortality , Pneumonia, Viral/transmission , Risk Assessment , Vaccine-Preventable Diseases/mortality
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