Estimate Vaccination Coverage Research Articles

Hepatitis B infection and immunity in Migrant Children and Pregnant Persons in Europe: A Systematic Review and Meta-Analysis.

The WHO's global hepatitis strategy aims to achieve viral hepatitis elimination by 2030. Migrant children and pregnant persons represent an important target group for prevention strategies. However, evidence on the burden of chronic hepatitis B (CHB) infection, and the factors affecting incidence, is lacking. EMBASE, Global Health, Global Index Medicus, Web of Science and Medline were searched for articles in any language from 1/1/2012 to 8/6/2022. Studies reporting CHB prevalence, disease severity, complications and/or prevention strategies including vaccination, prevention of vertical transmission, and access to care/treatment in migrant children and pregnant migrants were included. Pooled estimates of CHB prevalence and Hepatitis B vaccination (HBV) coverage among migrant children were calculated using random effects meta-analysis. 42 studies were included, 27 relating to migrant children and 15 to pregnant migrants across 12 European countries, involving data from 64 773 migrants. Migrants had a higher incidence of CHB than host populations. Among children, the pooled prevalence of CHB was higher for unaccompanied minors (UAM) (5%, [95% CI: 3-7%]) compared to other child migrants including internationally adopted children (IAC) and refugees (1%, [95% CI: 1-2%]). Region of origin was identified as a risk factors for CHB, with children from Africa and pregnant migrants from Africa, Eastern Europe and China at highest risk. Pooled estimates of HBV vaccine coverage were lower among UAM (12%, [95% CI: 3-21%]) compared to other child migrants (50%, [95% CI: 37-63%]). A range of modifiable determinants of HBV prevalence in migrant children and pregnant persons were identified including sub-optimal screening, prevention, and continuum of care. There is a need to develop evidence-based approaches in hepatitis care for these groups, thereby contributing towards global viral hepatitis elimination goals.

Impact of rotavirus vaccination in Malawi from 2012 to 2022 compared to model predictions before, during, and after the COVID-19 pandemic.

Rotarix® rotavirus vaccine was introduced into the Malawi national immunization program in October 2012. We used a previously developed mathematical models to estimate overall vaccine effectiveness over a 10-year period following rotavirus vaccine introduction. We analyzed data on children <5 years old hospitalized with acute gastroenteritis in Blantyre, Malawi from January 2012 to June 2022, compared to pre-vaccination data. We estimated vaccine coverage before, during, and after the COVID-19 pandemic using data from rotavirus-negative children. We compared model predictions for the weekly number of rotavirus-associated gastroenteritis (RVGE) cases to the observed number by age to validate model predictions and estimate overall vaccine effectiveness. The number of RVGE and rotavirus-negative acute gastroenteritis cases declined substantially following vaccine introduction. Vaccine coverage among rotavirus-negative controls was >90% with two doses by July 2014, and declined to a low of ~80% in October 2020, before returning to pre-pandemic levels by July 2021. Our models captured the post-vaccination trends in RVGE incidence, with 5.4% to 19.4% of observed weekly RVGE cases falling outside of the 95% prediction intervals. Comparing observed RVGE cases to the model-predicted incidence without vaccination, overall vaccine effectiveness was estimated to be 36.0% (95% prediction interval: 33.6%, 39.9%) peaking in 2014 and was highest in infants (52.5%; 95% prediction interval: 50.1%, 54.9%). Overall effectiveness of rotavirus vaccination in Malawi is modest despite high vaccine coverage and has plateaued since 2016. Our mathematical models provide a validated platform for assessing strategies to improve rotavirus vaccine impact.

Population-based denominators matter: Bias in U.S. Virgin Islands COVID-19 vaccination coverage under changing population counts

PurposeThe U.S. Virgin Islands (USVI) receives an updated population count once every 10 years and used 2010 decennial census population counts to estimate COVID-19 vaccination coverage during the COVID-19 emergency response. We investigated whether using outdated (2010) or modeled (2020 international database [IDB]) population counts biased vaccination coverage estimates used to inform public health priorities during the 2020–2022 COVID-19 response. MethodsWe estimated percentage of USVI residents with a completed primary COVID-19 vaccination series during December 16, 2020–September 20, 2022. Vaccination coverage was calculated as number of persons who completed the vaccination series divided by 2010 and 2020 decennial census population counts and 2020 IDB intercensal estimate. ResultsCOVID-19 vaccination coverage using the 2020 population count was 12 % points higher than coverage using 2010 denominator (2010 denominator: 51 %; 2020 denominator: 63 %). Vaccination coverage estimated using 2020 IDB was approximately equal with the 2010 decennial census estimate (52 %). ConclusionsUsing 2010 and modeled population counts underestimated 2020 USVI COVID-19 vaccination coverage given the 18 % population decline during 2010–2020, potentially limiting USVI’s ability to assess vaccination progress. Identifying mechanisms for more reliable population enumeration or improved estimate modeling are essential for accurately guiding USVI public health decision-making.

Global vaccine coverage and childhood survival estimates: 1990-2019.

To quantify the association between reduction in child mortality and routine immunization across 204 countries and territories from 1990 to 2019. We used child mortality and vaccine coverage data from the Global Burden of Disease Study. We used a modified child survival framework and applied a mixed-effects regression model to estimate the reduction in deaths in children younger than 5years associated with eight vaccines. Between 1990 and 2019, the diphtheria-tetanus-pertussis (DTP), measles, rotavirus and Haemophilus influenzae type b vaccines were significantly associated with an estimated 86.9 (95% confidence interval, CI: 57.2 to 132.4) million fewer deaths in children younger than 5years worldwide. This decrease represented a 24.2% (95% CI: 19.8 to 28.9) reduction in deaths relative to a scenario without vaccines. The DTP and measles vaccines averted 46.7 (95% CI: 30.0 to 72.7) million and 37.9 (95% CI: 25.4 to 56.8) million deaths, respectively. Of the total reduction in child mortality associated with vaccines, 84.2% (95% CI: 83.0 to 85.1) occurred in 73 countries supported by Gavi, the Vaccine Alliance, with an estimated 45.4 (95% CI: 29.8 to 69.2) million fewer deaths from 2000 to 2019. The largest reductions in deaths associated with these four vaccines were in India, China, Ethiopia, Pakistan and Bangladesh (in order of the size of reduction). Vaccines continue to reduce childhood mortality significantly, especially in Gavi-supported countries, emphasizing the need for increased investment in routine immunization programmes.

Estimates of Seasonal Influenza Burden That Could Be Averted by Improved Influenza Vaccines in the Australian Population Aged Under 65 Years, 2015-2019.

The interpretation of relative vaccine effectiveness (rVE) of improved influenza vaccines is complex. Estimation of burden averted is useful to contextualise their potential impact across different seasons. For the population aged under 65 years in Australia, this study estimated the additional morbidity and mortality that could be averted using improved influenza vaccines. We used observed, season-specific (2015-2019) influenza notification and influenza-coded hospitalisation frequencies and published modelled estimates of influenza-associated hospitalisations and deaths that occurred under the prevailing influenza vaccination coverage scenario. After back-calculating to the estimated burden in the population without vaccination, we applied published standard influenza vaccine effectiveness and coverage estimates to calculate the burden potentially averted by standard and improved influenza vaccines. A plausible range of rVE values were used, assuming 50% coverage. The percentage point difference in absolute vaccine effectiveness (VE) of an improved vaccine compared to a standard vaccine is directly proportional to its rVE and inversely proportional to the effectiveness of the standard vaccine. The incremental burden averted by an improved vaccine is a function of both its difference in absolute VE and the severity of the influenza season. Assuming an rVE of 15% with 50% coverage, the improved vaccine was estimated to additionally avert 1517 to 12,641 influenza notifications, 287 to 1311 influenza-coded hospitalisations and 9 to 33 modelled all-cause influenza deaths per year compared to the standard vaccine. Improved vaccines can have substantial clinical and population impact, particularly when the effectiveness of standard vaccines is low, and burden is high.

Elimination of Mother-to-Child Transmission of Hepatitis B Virus in Gulf Cooperation Council Countries: Current Status and Future Prospects.

The WHO member states endorsed the goal to eliminate mother-to-child transmission (EMTCT) of hepatitis B virus (HBV) by 2030, which requires achievement of ≥90% coverage with timely hepatitis B birth dose (HepB-BD), three doses of the hepatitis B vaccine (HepB3), and a hepatitis B surface antigen (HBsAg) seroprevalence ≤0.1% in children. We assessed the progress made to achieve EMTCT of HBV in Gulf Cooperation Council (GCC) countries. Data was extracted from National Viral Hepatitis Strategic Frameworks and WHO hepatitis B vaccination coverage estimates during 2018-2022 for all GCC countries. We also reviewed the literature to summarize the prevalence of HBsAg in children. During 2018-2022, coverage with timely HepB-BD and HepB3 was >90% in all countries. All newborns irrespective of whether parents are nationals or immigrants/expatriates receive HepB-BD and other routine immunization vaccines. Prevalence of HBsAg among children was available in three of six GCC countries; it ranged from 0% in Qatar and Saudi Arabia to 0.4% in Oman. Five countries reported screening pregnant women for HBsAg, and three provided antiviral treatment of those eligible, and hepatitis B immunoglobulin to exposed newborns. In conclusion, all GCC countries achieved hepatitis B vaccination targets and countries with available data have either achieved or are close to achieving EMTCT of HBV. Remaining countries need to implement hepatitis B serosurveys to track progress to EMTCT of HBV.

Covid-19 pandemic and equity of global human papillomavirus vaccination: descriptive study of World Health Organization-Unicef vaccination coverage estimates

ObjectiveTo analyse progress in global vaccination against human papillomavirus (HPV) during the covid-19 pandemic, with a particular focus on equity.DesignDescriptive study of World Health Organization-Unicef vaccination coverage estimates.SettingWHO-Unicef estimates of...

Estimating county-level vaccination coverage using small area estimation with the National Immunization Survey-Child

The National Immunization Survey-Child (NIS-Child) provides annual vaccination coverage estimates in the United States for children aged 19 through 35 months, nationally, for each state, and for select local areas and territories. There is a need for vaccination coverage estimates for smaller geographic areas to support local authority planning and identify counties with potentially low vaccination coverage for possible further intervention. We describe small area estimation methods using 2008-2018 NIS-Child data to generate county-level estimates for children up to two years of age born 2007-2011 and 2012-2016. We applied an empirical best linear unbiased prediction method to combine direct estimates of vaccination coverage with model-based prediction using county-level predictors regarding health and demographic characteristics. We review the predictors commonly selected for the small area models and note multiple predictors related to barriers to vaccination.

Cost-effectiveness of human papillomavirus (HPV) vaccination in Burkina Faso: a modelling study

BackgroundAfrica has some of the highest cervical cancer incidence and mortality rates globally. Burkina Faso launched a human papillomavirus (HPV) vaccination programme for 9-year-old girls in 2022 with support from Gavi, the Vaccine Alliance (Gavi). An economic evaluation of HPV vaccination is required to help sustain investment and inform decisions about optimal HPV vaccine choices.MethodsWe used a proportionate outcomes static cohort model to evaluate the potential impact and cost-effectiveness of HPV vaccination for 9-year-old girls over a ten-year period (2022–2031) in Burkina Faso. The primary outcome measure was the cost (2022 US$) per disability-adjusted life year (DALY) averted from a limited societal perspective (including all vaccine costs borne by the government and Gavi, radiation therapy costs borne by the government, and all other direct medical costs borne by patients and their families). We evaluated four vaccines (CERVARIX®, CECOLIN®, GARDASIL-4®, GARDASIL-9®), comparing each to no vaccination (and no change in existing cervical cancer screening and treatment strategies) and to each other. We combined local estimates of HPV type distribution, healthcare costs, vaccine coverage and costs with GLOBOCAN 2020 disease burden data and clinical trial efficacy data. We ran deterministic and probabilistic uncertainty analyses.ResultsHPV vaccination could prevent 37–72% of cervical cancer cases and deaths. CECOLIN® had the most favourable cost-effectiveness (cost per DALY averted < 0.27 times the national gross domestic product [GDP] per capita). When cross-protection was included, CECOLIN® remained the most cost-effective (cost per DALY averted < 0.20 times the national GDP per capita), but CERVARIX® provided greater health benefits (66% vs. 48% reduction in cervical cancer cases and deaths) with similar cost-effectiveness (cost per DALY averted < 0.28 times the national GDP per capita, with CECOLIN® as the comparator). We estimated the annual cost of the vaccination programme at US$ 2.9, 4.1, 4.4 and 19.8 million for CECOLIN®, GARDASIL-4®, CERVARIX® and GARDASIL-9®, respectively. A single dose strategy reduced costs and improved cost-effectiveness by more than half.ConclusionHPV vaccination is cost-effective in Burkina Faso from a limited societal perspective. A single dose strategy and/or alternative Gavi-supported HPV vaccines could further improve cost-effectiveness.

A Practical Guide to Pilot Testing Community-Based Vaccination Coverage Surveys.

Pilot testing is crucial when preparing any community-based vaccination coverage survey. In this paper, we use the term pilot test to mean informative work conducted before a survey protocol has been finalized for the purpose of guiding decisions about how the work will be conducted. We summarize findings from seven pilot tests and provide practical guidance for piloting similar studies. We selected these particular pilots because they are excellent models of preliminary efforts that informed the refinement of data collection protocols and instruments. We recommend survey coordinators devote time and budget to identify aspects of the protocol where testing could mitigate project risk and ensure timely assessment yields, credible estimates of vaccination coverage and related indicators. We list specific items that may benefit from pilot work and provide guidance on how to prioritize what to pilot test when resources are limited.

Childhood vaccination coverage and regional differences in Swiss birth cohorts 2012–2021: Are we on track?

AimsMany western countries are challenged by delayed and insufficient vaccination coverage rates in children, and thus missing WHO coverage targets. This study aimed to estimate vaccination coverage and timeliness in Swiss children over a decade. Furthermore, we evaluated the impact of COVID-19, regional variations, and the adherence to the amended vaccination schedule in 2019. MethodsRetrospective observational study with Swiss health insurance claims data including birth cohorts 2012–2021 of children continuously observed until ages 13, 25, and 48 months respectively. We used population-weighted proportions and time-to-event analyses to describe coverage and timeliness of diphtheria/tetanus/pertussis/poliomyelitis/haemophilus influenzae type b (DTaP-IPV-Hib), measles/mumps/rubella (MMR), hepatitis B (HBV), pneumococcal (PCV), and meningococcal (MCV) vaccinations according to the national schedule. The potential impact of COVID-19 and vaccination schedule adherence were evaluated descriptively. Logistic regression was used to investigate regional factors potentially associated with non-vaccination. Results120,073 children, representing between 12 and 17 % of all Swiss children born in corresponding years, were included. Coverage remained stable or improved over the years. The 2019 amendment of the national immunization schedule was associated with an increase of ~10 % points in full coverage in Swiss children for DTaP-IPV-Hib, MMR and HBV despite the concurrent COVID-19 pandemic. Nonetheless, full vaccination coverage remained below 90 % with many vaccination series being delayed or not completed. The comparison across the different vaccines revealed large differences in coverage. Moreover, we observed large regional differences in non-vaccination with children living in rural and German-speaking areas more likely to be entirely unvaccinated. ConclusionFull vaccination coverage in Swiss children is still below 90 % with many vaccinations administered delayed. Given regional differences, missed or delayed booster vaccinations, and differences in vaccine-specific acceptability, more effort may be needed to achieve national vaccination targets.

Influenza vaccination in Western Australian children: Exploring the health benefits and cost savings of increased vaccine coverage in children

IntroductionTo assess potential benefits and direct healthcare cost savings with expansion of an existing childhood influenza immunisation program, we developed a dynamic transmission model for the state of Western Australia, evaluating increasing coverage in children < 5 years and routinely immunising school-aged children. MethodsA deterministic compartmental Susceptible-Exposed-Infectious-Recovered age-stratified transmission model was developed and calibrated using laboratory-notification and hospitalisation data. Base case vaccine coverage estimates were derived from 2019 data and tested under moderate, low and high vaccine effectiveness settings. The impact of increased coverage on the burden of influenza, influenza-associated presentations and net costs were assessed using the transmission model and estimated health utilisation costs. ResultsUnder base case vaccine coverage and moderate vaccine effectiveness settings, 225,460 influenza cases are expected annually across all ages. Direct healthcare costs of influenza were estimated to be A$27,608,286 per annum, dominated by hospital costs. Net cost savings of >$A1.5 million dollars were observed for every 10 % increase in vaccine coverage in children < 5 years. Additional benefits were observed by including primary school age children (5–11 years) in the funded influenza vaccination program - a reduction in cases, presentations, hospitalisations and approximately $A4 million net costs savings were observed for every 10 % increase in coverage. The further addition of older children (12–17 years) resulted in only moderate additional net cost savings figures, compared with a 5–11year-old program alone. Net costs savings were predominantly derived by a reduction in influenza-associated hospitalisation in adults. ConclusionsAny increase in influenza vaccine coverage in children < 5 years, above a base case of 50 % coverage resulted in a substantive reduction in influenza cases, presentations, hospitalisations and net costs when applied to the West Australian population. However, the most impactful pediatric program, from both a disease prevention and costs perspective, would be one that increased vaccination coverage among primary-school aged children.

Malaria vaccine coverage estimation using age-eligible populations and service user denominators in Kenya

BackgroundThe World Health Organization approved the RTS,S/AS01 malaria vaccine for wider rollout, and Kenya participated in a phased pilot implementation from 2019 to understand its impact under routine conditions. Vaccine delivery requires coverage measures at national and sub-national levels to evaluate progress over time. This study aimed to estimate the coverage of the RTS,S/AS01 vaccine during the first 36 months of the Kenyan pilot implementation.MethodsMonthly dose-specific immunization data for 23 sub-counties were obtained from routine health information systems at the facility level for 2019–2022. Coverage of each RTS,S/AS01 dose was determined using reported doses as a numerator and service-based (Penta 1 and Measles) or population (projected infant populations from WorldPop) as denominators. Descriptive statistics of vaccine delivery, dropout rates and coverage estimates were computed across the 36-month implementation period.ResultsOver 36 months, 818,648 RTSS/AS01 doses were administered. Facilities managed by the Ministry of Health and faith-based organizations accounted for over 88% of all vaccines delivered. Overall, service-based malaria vaccine coverage was 96%, 87%, 78%, and 39% for doses 1–4 respectively. Using a population-derived denominator for age-eligible children, vaccine coverage was 78%, 68%, 57%, and 24% for doses 1–4, respectively. Of the children that received measles dose 1 vaccines delivered at 9 months (coverage: 95%), 82% received RTSS/AS01 dose 3, only 66% of children who received measles dose 2 at 18 months (coverage: 59%) also received dose 4.ConclusionThe implementation programme successfully maintained high levels of coverage for the first three doses of RTSS/AS01 among children defined as EPI service users up to 9 months of age but had much lower coverage within the community with up to 1 in 5 children not receiving the vaccine. Consistent with vaccines delivered over the age of 1 year, coverage of the fourth malaria dose was low. Vaccine uptake, service access and dropout rates for malaria vaccines require constant monitoring and intervention to ensure maximum protection is conferred.

Using probabilistic linkage to improve estimates of access to services among the migrant population: The case of access to immunisation programs in Chile

ObjectivesGovernments often struggle to accurately estimate the number of migrants using public services due to the lack of a unique national ID. We aim to study this in the context of migrant access to immunization programs in Chile and estimate vaccine coverage in school-age children.&#x0D; MethodsTo estimate vaccine coverage for migrant school-age children, we combined data from two databases: the Chilean National Immunization Register (which contained 77.9 million records) and the School Enrollment database (which contained around 68 million records, representing about 3.6 pupils per year). Using Splink, a Python package developed by the UK Ministry of Justice, we created a probability linkage model to link and deduplicate records of migrants who lack a unique national ID. The following linkage keys were considered in the model: first and second name, first and last name and date of birth. Linkage quality was evaluated using ‘gold standard data.&#x0D; ResultsIn 2022, we find that out of 3,644,467 students enrolled in school, 140,317 of them were migrants who didn't have a Chilean national ID. Additionally, in the NIR database, 5.2 out of 77.9 million records belonged to migrants without a national ID. After removing duplicates from both databases, our linkage model determined that 52,524 of the 140,317 students without a national ID in SE were linked to NIR (37.4%). We find that excluding migrants without national IDs when estimating national vaccine coverage for school-aged children leads to an underestimation of 2%, from 86% to 88%.&#x0D; ConclusionOur findings emphasize the significance of utilizing linkage techniques in order to accurately estimate access to public services for migrant populations who typically lack a national ID. By linking their records across public institutions, more reliable data can be obtained.

Flu vaccination coverage in Italy in the COVID-19 era: A fuzzy functional k-means (FFKM) approach

BackgroundIn Europe, flu vaccination coverage has decreased, and there are complex barriers to overcome to vaccinate against flu. Many studies have been conducted to estimate vaccination coverage. The COVID-19 pandemic threatens to disrupt immunization programs in many countries, including Italy, where vaccination against the flu is recommended but not mandatory. This paper aims to understand changes in flu vaccine uptake in Italian regions. MethodsUsing functional data analysis and fuzzy functional k-means clustering, we investigated changes in flu vaccine coverage in Italian regions before (2010–2019) and after (2020–2022) the COVID-19 vaccination period. ResultsThe period of COVID-19 pandemic brought an increase in vaccine coverage globally. Elbow's method determined that the optimal number of clusters in vaccination uptake is 2. Apulia, Basilicata, Emilia Romagna, Liguria, Molise, Tuscany, and Umbria in 2019 belong less to the group with low flu vaccination uptake (G1) but increase their tendency to belong to this group over time: they decrease their propensity to be vaccinated for flu. For others, it seems that COVID-19 served as a push to increase flu vaccination coverage rates. Sicily appears to be the region that has responded best to the pandemic, changing its membership value from 2019 to 2022. ConclusionThe present study highlights that the COVID-19 era has resulted in a higher flu vaccination coverage rate. Moreover, the regional level's improvement or worsening in flu vaccination coverage rate is not affected by the historical gap and socio-cultural and economic differences prevailing among Italian regions.

Innovative approach in assessing the children's immunization status when it cannot be documented.

During surveys, it is recommended that children immunization status should be based on immunization documents. It has been noted that in some communities, a number of children are claimed to be vaccinated but have no evidence of vaccination. This work is proposed to estimate routine immunization coverage in children based on both documented vaccination and the tracking of undocumented immunization. It was a community-based survey targeting children aged 0-59 months in which the immunization status of children was assessed based on vaccination documents and based on a questionnaire tracking immunization sites and period for children with undocumented vaccination. The vaccination coverage and completeness were estimated from data collected in immunization cards and re-estimated after tracking the immunization status of children with no immunization cards. Of 1435 children reached in households, 1430 (99.7%) were included. Of 1072 children aged 12-59 months, 194 (18.1%) received DPT-Hi+Hb 3 with evidence and 399 (37.2%) with evidence and tracking. In the same age group, the dropout rate from DPT-Hi+Hb 1 (157 doses administered) to DPT-Hi+Hb 3 (127 doses administered) with evidence was 19.1% and 42.4% with evidence and tracking. The tracking of immunization status in children with no evidence of vaccination allows to determine their immunization status and to improve the reliability of the estimated vaccination coverage. This strategy could be adopted to be part of the planning and implementation of vaccination coverage surveys of EPI vaccines.

Lessons learned from the COVID-19 pandemic for improved influenza control

The World Health Organization noted that COVID-19 vaccination programmes could be leveraged to deliver influenza vaccination. In 2008, the International Federation of Pharmaceutical Manufacturers and Associations’ (IFPMA) Influenza Vaccine Supply International Task Force (IVS) developed a survey method using the number of influenza vaccine doses distributed globally to estimate vaccination coverage rates. Seven hundred and ninety-seven million doses were distributed in 2021, representing a 205% increase over the 262 million doses distributed in 2004, exceeding the number of doses distributed during and after the 2009–2010 influenza pandemic. The most obvious explanation for the global increase is the enabling of critical elements of the vaccine ecosystem by decision-makers during the COVID-19 pandemic to reinforce implementation of influenza vaccination programs. Most of the improvements in performance of influenza programs during the COVID-19 pandemic can be classified in four categories: 1) promoting vaccination using tailored approaches for specific populations; 2) improving convenient access to influenza vaccines in COVID-safe settings; 3) improving reimbursement of seasonal influenza vaccination for priority groups; 4) maintaining the timing of vaccination to the autumn. In spite of the increase in rates of seasonal influenza vaccines distributed during the COVID-19 pandemic, globally, the rate of influenza dose distribution is sub-optimal, and a considerable proportion of the influenza infections remains preventable. To sustain the benefits from increased uptake of influenza vaccines, governments need to sustain the efforts made during the COVID-19 pandemic, and a number of global policy endeavours should be undertaken, including developing a clear global roadmap for achieving influenza control objectives, adopted by a WHA resolution, in line with the strategic objective 3 of the Global Influenza Strategy 2030, embedded in the Immunization Agenda 2030 (IA2030).

Additional Burden Averted in the United States From Use of MF59-Adjuvanted Seasonal Influenza Vaccine Compared With Standard Seasonal Influenza Vaccine Among Adults ≥65 Years.

The MF59-adjuvanted trivalent inactivated influenza vaccine (aIIV3) is designed to overcome immunosenescence and enhance vaccine responses in older adults. We expanded on the Centers for Disease Control and Prevention (CDC) modeling method to estimate the number of additional influenza-related outcomes averted with aIIV3 versus generic quadrivalent inactivated influenza vaccine (IIV4) in adults ≥65 years over 3 influenza seasons (2017-2018 to 2019-2020) in the United States. A static compartmental model was developed based on an existing CDC model with 2 previously recommended calculation methods that increased the accuracy of the model in providing estimates of burden averted. Model inputs included vaccine effectiveness, vaccine coverage, population counts, and disease burden estimates. Additional burden averted (symptomatic cases, outpatient visits, hospitalizations, intensive care unit [ICU] admissions, and deaths) was expressed as total incremental cases averted between the vaccines. Sensitivity analyses tested the resilience of the model results to uncertainties in model inputs. The model estimated that vaccination with aIIV3 versus IIV4 would avert 2.24 times as many symptomatic cases, outpatient visits, hospitalizations, ICU stays, and deaths during 2017-2018; the burden averted in 2018-2019 and 2019-2020 with aIIV3 would be 3.44 and 1.72 times that averted with IIV4, respectively. Disease burden estimates and relative vaccine effectiveness of aIIV3 had the greatest impact on model estimates. Over 3 influenza seasons, the model estimated that aIIV3 was more effective than IIV4 in averting influenza-related outcomes, preventing 1.72 to 3.44 times as many influenza illnesses with proportionate decreases in related healthcare use and complications.

The Trajectory of Brazilian Immunization Program between 1980 and 2018: From the Virtuous Cycle to the Vaccine Coverage Decline.

Public health policies are crossed by economic and political interests that can affect the maintenance of the immunization programs and their vaccination coverages. The aim was to investigate the political and economic conditions that marked the trajectory of the Brazilian immunization program from 1980 to 2018. Documentary research gathered data on public expenditures with epidemiological surveillance and vaccine procurement and nationwide estimates of vaccine coverage. The scientific literature on the program's implementation and the country's political and economic conditions was examined. The theoretical approach was based on historical institutionalism. The results showed rising, high rates maintaining and falling vaccination coverages in the period. As of 2010, there was a tendency for a reduction in total federal spending on epidemiological surveillance, putting pressure on the budgets of the sub-national governments in their respective areas of coverage, and on federal spending in dollars for the acquisition of immunobiologicals and inputs. The amplitude and complexity of the program's trajectory have been crossed by diverse dynamics conditioned by economic and political interests reflecting at a deeper level the advance of capitalism through fiscal austerity measures over democracy's aspirations for greater balance and justice in the distribution of resources.

Influenza and Tetanus, Diphtheria, and Acellular Pertussis Vaccination Coverage During Pregnancy: Pregnancy Risk Assessment Monitoring System, 2020.

Estimates of vaccination coverage during pregnancy and identification of disparities in vaccination coverage can inform vaccination campaigns and programs. We reported the prevalence of being offered or told to get the influenza vaccine by a health care provider (hereinafter, provider); influenza vaccination coverage during the 12 months before delivery; and tetanus, diphtheria, and acellular pertussis (Tdap) vaccination coverage during pregnancy among women with a recent live birth in the United States. We analyzed 2020 data from the Pregnancy Risk Assessment Monitoring System from 42 US jurisdictions (n = 41 673). We estimated the overall prevalence of being offered or told to get the influenza vaccine by a provider and influenza vaccination coverage during the 12 months before delivery. We estimated Tdap vaccination coverage during pregnancy from 21 jurisdictions with available data (n = 22 020) by jurisdiction and select characteristics. In 2020, 84.9% of women reported being offered or told to get the influenza vaccine, and 60.9% received it, ranging from 35.0% in Puerto Rico to 79.7% in Massachusetts. Influenza vaccination coverage was lower among women who were not offered or told to get the influenza vaccine (21.4%) than among women who were offered or told to get the vaccine (68.1%). Overall, 72.7% of women received the Tdap vaccine, ranging from 52.8% in Mississippi to 86.7% in New Hampshire. Influenza and Tdap vaccination coverage varied by all characteristics examined. These results can inform vaccination programs and strategies to address disparities in vaccination coverage during pregnancy and may inform vaccination efforts for other infectious diseases among pregnant women.