ß-Lactamase and Macrolide Resistance Gene Carriage in Escherichia coli Isolates Among Children Discharged From Inpatient Care in Western Kenya: A Cross-sectional Study.

Background: Antimicrobial resistance (AMR) is a global threat to infectious disease control, particularly among recently hospitalized children. We sought to determine the prevalence and mitigating factors of resistance in enteric Escherichia coli among children discharged from health facilities in western Kenya. Methods: Between June 2016 and November 2019, children aged 1 to 59 months were enrolled at the point of discharge from the hospital. E coli was isolated by microbiological culture from rectal swabs at baseline. ß-Lactamases and macrolide resistance-conferring genes were detected by polymerase chain reaction. A modified Poisson regression model was used to assess the predictors mph(A) and CTX-M-type extended-spectrum ß-lactamase (ESBL). Results: Of the 238 children whose E coli isolates were tested, 91 (38.2%) and 109 (45.8%) had detectable CTX-M-type ESBL and mph(A) genes, respectively. Antibiotic treatment during hospitalization (adjusted prevalence ratio [aPR], 2.47; 95% CI, 1.12-5.43; P = .025), length of hospitalization (aPR, 1.42; 95% CI, 1.00-2.01; P = .052), and the practice of open defecation (aPR, 2.47; 95% CI, 1.40-4.36; P = .002) were independent predictors for CTX-M-type ESBL and mph(A) genes. Pneumococcal vaccination was associated with a 43% lower likelihood of CTX-M-type ESBL (aPR, 0.57; 95% CI, .38-.85; P = .005), while measles vaccination was associated with a 32% lower likelihood of mph(A) genes (aPR, 0.68; 95% CI, .49-.93; P = .017) in E coli isolates. Conclusions: Among children discharged from the hospital, history of vaccination, shorter hospital stay, lack of in-hospital antibiotic exposure, and improved sanitation were associated with a lower likelihood of AMR genes. To mitigate the continued spread of AMR, AMR control programs should consider strategies beyond antimicrobial stewardship, including improvements in sanitation, increased vaccine coverage, and the development of novel vaccines.

Compulsory Vaccination Coverage in 12 Sub-Saharan African Countries Two Years Following the COVID-19 Pandemic.

The coronavirus disease 2019 (COVID-19) pandemic is a global threat, challenging health services' provision and utilization. This study aimed to assess compulsory vaccination coverage in 12 Sub-Saharan African countries two years following the COVID-19 pandemic using the Health Belief Model. A cross-sectional survey was conducted from November 1 to December 15, 2022. Multivariate logistic regression was conducted to identify the determinants of vaccination coverage. Among the 5032 respondents, 73.1% reported that their children received compulsory vaccination. The lowest coverage was observed in Ghana (36.5%), while the highest was in Burkina Faso and Congo (92.0%). Factors associated with non-vaccination included older mothers (adjusted odds ratio (AOR) = 1.04, 95%CI: 1.03-1.05), lower mothers' education, older children (AOR = 0.76, 95%CI: 0.60-0.96), children with chronic illnesses (AOR = 0.55, 95%CI: 0.45-0.66), and difficult accessibility to healthcare facilities (AOR = 11.27, 95%CI: 9.48-13.44). Low perceived risk, in which non-vaccinated children were believed to be at no higher risk for infectious diseases and the disease severity would not worsen among non-vaccinated children, increased the likelihood of non-vaccination (AOR = 2.29, 95%CI: 1.75-2.99 and AOR = 2.12, 95%CI: 1.64-2.73, respectively). Perceiving vaccines as unnecessary, and needless for breastfed babies increased the probability of non-vaccination (AOR = 1.38, 95%CI: 1.10-1.73 and AOR = 1.69, 95%CI: 1.31-2.19, respectively). Higher odds of non-vaccination were found when the provision of vaccine information did not motivate parents to vaccinate their children (AOR = 4.29, 95%CI: 3.15-5.85). Conversely, believing that vaccines were safe for children decreased the odds of non-vaccination (AOR = 0.72, 95%CI: 0.58-0.88). Parental perceptions and concerns should be considered in interventions aiming to increase compulsory vaccine acceptance and coverage.

Comparing vaccination coverage before and during COVID-19 pandemic in children under one year in the health district of commune V in Bamako, Mali.

INTRODUCTION: Although an essential frontline service in the prevention of child morbidity and mortality, there are indications that routine vaccinations have been disrupted during the COVID-19 pandemic. The present study aimed to compare vaccination coverage before COVID-19 in Mali in 2019 and during COVID-19 in 2020. OBJECTIVE: To compare vaccination coverages before COVID-19 in Mali in 2019 and during COVID-19 in 2020. DESIGN: Cross-sectional study. SETTING AND PARTICIPANTS: We collected routine immunization data from 2019 to 2020 of children under one year in the health district of Commune V in Bamako which includes twelve community health centers (CSCom). RESULTS: Considering all vaccines together, coverage in 2019 was higher than in 2020 (88.7% vs. 71,6%) (p < 10- 3, Fig. 1). In 2020, low proportions of children vaccinated were observed in May (51.1%) two months after the first COVID-19 case in Mali on March 25, 2020. For all vaccines, the mean number of children vaccinated was significantly higher in 2019 (before COVID-19) as compared to 2020 (during COVID-19) (p < 0.05). However, in September and October 2019 BCG vaccine coverage was lower in 2019 as compared to 2020 (p < 10- 3). CONCLUSION: COVID-19 pandemic has affected routine childhood vaccine coverage in Commune V of Bamako, particularly in May 2020. Therefore, new strategies are needed to improve vaccine coverage in young children below 1.

The impact of the COVID-19 pandemic on vaccination uptake in the United States and strategies to recover and improve vaccination rates: A review.

The COVID-19 pandemic disrupted routine healthcare delivery, causing declines in CDC-recommended vaccination rates across the life-course in the United States (US). Ensuring protection against disease outbreaks and associated morbidity and mortality depends on improving vaccine coverage rates (VCRs) and uptake. The authors conducted a targeted literature review to assess the pandemic's effects on routine vaccination rates across different populations, evaluating VCR recovery and improvement efforts. The review highlights articles published with data measuring or evaluating VCR decline across the US during the COVID-19 pandemic from January 2020 to April 2022, associated health impacts, and policy and programmatic strategies to recover routine VCRs. While vaccination rates stagnated or declined across some populations pre-pandemic, the review indicated there were further VCR declines in 2020 and 2021 compared to 2019 across numerous CDC-recommended vaccines, ages, and geographies, with some vaccines and sub-populations disproportionally impacted. The review additionally identified declines in patient healthcare visit frequency and increases in morbidity and mortality associated with vaccine-preventable disease (VPD) complications. Reviewed publications highlighted multifaceted strategies that could aid in recovering VCRs. Overall, findings demonstrate a significant reduction in VCRs across all age groups and highlight promising solutions to inform vaccine uptake efforts and ensure broader protection against VPDs.

Vaccination coverage in rural Burkina Faso under the effects of COVID-19: evidence from a panel study in eight districts.

BACKGROUND: Improving infant immunization completion and promoting equitable vaccination coverage are crucial to reducing global under-5 childhood mortality. Although there have been hypotheses that the impact of the COVID-19 pandemic would decrease the delivery of health services and immunization campaigns in low- and middle-income countries, the available evidence is still inconclusive. We conducted a study in rural Burkina Faso to assess changes in vaccination coverage during the pandemic. A secondary objective was to examine long-term trends in vaccination coverage throughout 2010-2021. METHODS: Using a quasi-experimental approach, we conducted three rounds of surveys (2019, 2020, 2021) in rural Burkina Faso that we pooled with two previous rounds of demographic and household surveys (2010, 2015) to assess trends in vaccination coverage. The study population comprised infants aged 0-13 months from a sample of 325 households randomly selected in eight districts (n = 736). We assessed vaccination coverage by directly observing the infants' vaccination booklet. Effects of the pandemic on infant vaccination completion were analyzed using multi-level logistic regression models with random intercepts at the household and district levels. RESULTS: A total of 736 child-year observations were included in the analysis. The proportion of children with age-appropriate complete vaccination was 69.76% in 2010, 55.38% in 2015, 50.47% in 2019-2020, and 64.75% in 2021. Analyses assessing changes in age-appropriate full-vaccination coverage before and during the pandemic show a significant increase (OR: 1.8, 95% CI: 1.14-2.85). Our models also confirmed the presence of heterogeneity in full vaccination between health administrative districts. The pandemic could have increased inequities in infant vaccination completion between these districts. The analyses suggest no disruption in age-appropriate full vaccination due to COVID-19. Our findings from our sensitivity analyses to examine trends since 2010 did not show any steady trends. CONCLUSION: Our findings in Burkina Faso do not support the predicted detrimental effects of COVID-19 on the immunization schedule for infants in low- and middle-income countries. Analyses comparing 2019 and 2021 show an improvement in age-appropriate full vaccination. Regardless of achieving and sustaining vaccination coverage levels in Burkina Faso, this should remain a priority for health systems and political agendas.

Impact of the COVID-19 pandemic on routine vaccination services in Shaanxi province, Northwest China: Non-pharmaceutical intervention period and mass COVID-19 vaccination period.

To better understand the impact of COVID-19 epidemic on routine vaccination, a cross-sectional study was carried out during non-pharmaceutical intervention period (2020) and mass COVID-19 vaccination period (2021) in Shaanxi province. Data on NIP (National Immunization Program, Free), nNIP (non-National Immunization Program, Paid), and COVID-19 vaccines inoculated and vaccination clinics were collected. At the beginning of the COVID-19 epidemic, the rate of routine vaccination clinics providing vaccination services was only 20.0%, rabies vaccination clinics was 89.9% and obstetric vaccination clinics was 95.9%. Compared with 2019 (as baseline), NIP vaccines inoculated in 2020 and 2021 decreased by 3.5% and 19.2%, respectively, on the contrary, nNIP vaccines increased by 25.8% and 34.7%, respectively. In 2021, 74.9% of vaccination clinics were involved in mass COVID-19 vaccination, and there was not a significant impact of mass COVID-19 vaccination on the number of other vaccines inoculated. Vaccination coverage of all NIP vaccines was not different from that in previous years. COVID-19 epidemic had a short-term impact on routine vaccination at beginning. The impact of mass COVID-19 vaccination on routine vaccination could even be ignored. The COVID-19 epidemic has once again made people realize the great harm of infectious diseases, and has improved everyone's willingness to receive routine vaccines.

Factors Associated with Vaccine Refusal (Polio and Routine Immunization) in High-Risk Areas of Pakistan: A Matched Case-Control Study.

BACKGROUND: Pakistan has subpar childhood immunization rates and immunization activities have faced several challenges over the past years. We evaluated the social-behavioral and cultural barriers and risk factors for refusal of polio, Routine Immunization (RI), or both in high-risk areas of poliovirus circulation. METHODS: A matched case-control study was conducted from April to July 2017 in eight super high-risk Union Councils of five towns in Karachi, Pakistan. A total of 3 groups, each with 250 cases, including refusals for the Oral Polio Vaccine (OPV) in campaigns (national immunization days and supplementary immunization activities), RI, and both, were matched with 500 controls and identified using surveillance records. Sociodemographic characteristics, household information, and immunization history were assessed. Study outcomes included social-behavioral and cultural barriers and reasons for vaccine refusal. Data were analyzed in STATA using conditional logistic regression. RESULTS: RI refusal was associated with illiteracy and fear of the vaccine's adverse effects, while OPV refusals were linked to the mother's decision authority and the assumption that the OPV caused infertility. Conversely, higher socioeconomic status (SES) and knowledge of and willingness to vaccinate with Inactivated Polio Vaccine (IPV) were inversely associated with RI; and lower SES, walking to the vaccination point, knowledge of IPV, and an understanding of contracting polio were inversely associated with OPV refusals, with the latter two also inversely associated with complete vaccine refusal. CONCLUSION: Education, knowledge and understanding of vaccines, and socioeconomic determinants influenced OPV and RI refusals among children. Effective interventions are needed to address knowledge gaps and misconceptions among parents.

Estimating global changes in routine childhood vaccination coverage during the COVID-19 pandemic, 2020-2021.

OBJECTIVES: The COVID-19 pandemic has disrupted the distribution of routine immunizations globally. Multi-country studies assessing a wide spectrum of vaccines and their coverage rates are needed to determine global performance in achieving vaccination goals. METHODS: Global vaccine coverage data for 16 antigens were obtained from WHO/UNICEF Estimates of National Immunization Coverage. Tobit regression was performed for all country-antigen pairs for which data were continuously available between 2015-2020 or 2015-2021 to predict vaccine coverage in 2020/2021. Vaccines for which multi-dose data were available were assessed to determine whether vaccine coverage for subsequent doses were lower than that of first doses. RESULTS: Vaccine coverage was significantly lower-than-predicted for 13/16 antigens in 2020 and all assessed antigens in 2021. Lower-than-predicted vaccine coverage was typically observed in South America, Africa, Eastern Europe, and Southeast Asia. There was a statistically significant coverage drop for subsequent doses of the diphtheria-tetanus-pertussis, pneumococcus, and rotavirus vaccines compared to first doses in 2020 and 2021. CONCLUSION: The COVID-19 pandemic exerted larger disruptions to routine vaccination services in 2021 than in 2020. Global efforts will be needed to recoup vaccine coverage losses sustained during the pandemic and broaden vaccine access in areas where coverage was previously inadequate.

Worldwide Child Routine Vaccination Hesitancy Rate among Parents of Children Aged 0-6 Years: A Systematic Review and Meta-Analysis of Cross-Sectional Studies.

Routine vaccine hesitancy is a major global health challenge observed in over 190 countries worldwide. This meta-analysis aims to determine the worldwide prevalence of routine vaccination hesitancy among parents of children aged 0-6. An extensive search was conducted in four scientific databases: PubMed, Scopus, Web of Science, and the Cochrane Library. Studies were included if they reported hesitancy related to WHO-recommended routine immunizations for children under 7 years of age. A single-arm meta-analysis was performed using the OpenMeta[Analyst] software. An initial search retrieved 5121 articles, of which only 23 publications, involving 29,131 parents, guardians, and caregivers from over 30 countries met the inclusion criteria and quality assessment. The cumulative prevalence of parental vaccine hesitancy was found to be 21.1% (95% CI = 17.5-24.7%, I2 = 98.86%, p < 0.001). When stratifying the prevalence of vaccine hesitancy per WHO region, significant variations were observed, ranging from 13.3% (95% CI = 6.7-19.9%, I2 = 97.72%, p < 0.001) in the Region of the Americas to 27.9% (95% CI = 24.3-31.4%) in the Eastern Mediterranean region. The study findings highlight the need for healthcare providers and governments to develop and improve comprehensive programs with communication strategies to reduce parental vaccine hesitancy.

Impact of COVID-19 Pandemic on Routine Immunization in State of Kuwait: Short-Term Disruption With Rebound in Vaccination Utilization.

Introduction: This study aimed to explore the impact of the COVID-19 pandemic on routine immunization along 4 abbreviated time frames: before the pandemic in 2019, stay-at-home period (March-May) in 2020, reopening period (June-August) in 2020, and corresponding months in 2021. Methods: A secondary analysis of immunization data in Kuwait during the prepandemic period in 2019, stay-at-home period (March-May) in 2020, reopening period (June-August) in 2020, and corresponding months in 2021 was conducted. All vaccines given at 2, 3, 6, 12, 18, and 24 months of age were included in the study. Results: The mean of total visits from March 2020 to May 2020 dropped (-28.9%) compared with the visits in March 2019-May 2019 and then increased during the reopening period in June 2020-August 2020 (+31.8%). All vaccinations scheduled for children aged ≤24 months showed a reduction. The greatest reduction was detected at age 24 months (-44.2%), followed by age 18 months (-36.5%) and then age 1 year (-28.8%). There were greater declines among non-Kuwaiti children than among Kuwaiti children for all types of vaccines. The mean of total visits in March 2021-May 2021 increased (+15.4%) compared with the mean in the same period in 2020. However, a reduction of -16.0% still exists compared with the reduction at baseline in 2019. Conclusions: The COVID-19 pandemic had a large impact on childhood vaccinations, with recovery in subsequent months.

Parental Willingness and Associated Factors of Pediatric Vaccination in the Era of COVID-19 Pandemic: A Systematic Review and Meta-Analysis.

A significant decline in pediatric vaccination uptake due to the COVID-19 pandemic has been documented. Little is known about the parental willingness and associated factors of pediatric vaccination during the COVID-19 pandemic. An extensive literature search in the databases of PubMed, Scopus, Web of Science, and EBSCOhost were conducted. A total of 20 eligible studies published from 2020-2022 were included for systematic summary by a thematic analysis, among which 12 studies were included in a meta-analysis conducted with R-4.2.1. The prevalence of parental willingness to childhood/routine vaccination and seasonal influenza vaccination was 58.6% (95%CI 2.8-98.6%) and 47.3% (95%CI 25.3-70.5%). Moreover, there is no sufficient evidence of significant change in parental willingness to childhood/routine vaccination, human papillomavirus vaccination, or pneumococcal conjugate vaccination during the pandemic. However, a significant increase in parental willingness to vaccinate their children against seasonal influenza was found. In addition to the factors of parental vaccination willingness/hesitancy that are well-studied in literature, children/parents' history of COVID-19 and children's perceived vulnerability to COVID-19 were associated with parental willingness. Developing synergetic strategies to promote COVID-19 vaccination together with other pediatric vaccination is warranted during the pandemic. This may help to improve and/or catch up the vaccine uptake of children during and/or after the COVID-19 pandemic.

A review of the sustainability of vaccine funding across Europe and implications for post-COVID policymaking.

BACKGROUND: Approaches to routine vaccine funding and the underlying budget-setting process vary greatly across European countries. The ongoing COVID-19 pandemic has put enormous pressure on healthcare systems, affecting resilience of the overall vaccine ecosystem. METHODS: This article reviews how vaccine budgets are structured across 8 European countries (England, Finland, France, Germany, Italy, Norway, Romania, and Spain). First a literature review of the landscape was undertaken, followed by expert interviews to review the findings and consider policy principles to secure prioritisation and sustainability of routine vaccination budgets post-COVID. RESULTS: The organisation of budgets and vaccine spending varies greatly across Europe. In 2/8 countries (France and Germany) vaccine spending is subsumed into a wider healthcare budget. In 2/8 countries (Italy and Romania) the budget differentiates public health and prevention spending from other areas of healthcare, though there is no standalone vaccine budget. In 4/8 countries (England, Finland, Norway and Spain) there is a standalone vaccine budget, however this may not cover all elements needed for immunisation delivery and is not always transparent. CONCLUSION: Ensuring adequate and dynamic country vaccine budgets, with horizon scanning approaches like in England and Finland, or flexible vaccines expenditures like Germany, would greatly help the timely availability of public funding for new vaccines and strengthen vaccines supply security in Europe through a more virtuous European vaccine ecosystem.

Assessment of the Timely Administration of Birth Dose Vaccines in Northern Nigeria and Associated Factors.

Background: Lack of a timely receipt of vaccines can cause uncertain immune response and under-vaccination. Hence, timely vaccination is crucial to ensure an infant's early protection. Objectives: To identify the age of presentation for the birth dose vaccines, vaccine antigens received and factors associated with vaccination presentation by day one in Northern Nigeria. Method: A descriptive cross-sectional study involving 1 952 mother-infant pairs enrolled from 5 different states in Northern Nigeria. Data was collected using a questionnaire including the socio-demographic, antenatal care (ANC), delivery details, birth dates, vaccination presentation and birth vaccine antigens received. Data analysis was done with the SPSS-21 software. Findings: The median age of the infants at presentation for birth vaccines was six (interquartile range 2-16) days. A total of 413 (21.2%) infants were brought by the day of birth (day 0) or the next day (Day one), while one-fifth (20.6%) presented after Day 28. The most frequently received antigen was the Bacille-Calmette-Guerin by 1 781 infants (91.2%), oral polio vaccine 1 703 (87.2%), and hepatitis B vaccine birth dose the lowest at 75.1% (1 565). The commonest reasons for delayed presentations were an ill baby (24.7%) and an ill mother (21.9%).Factors associated with presentation within Day one post-birth were hospital delivery (OR-1.67, 95% CI; 1.28-2.19), firstborn (OR-1.40; 95%CI; 1.02-1.93), Christianity (OR-2.14 95% CI; 1.63-2.81), and mother with tertiary education (OR-1.62, 95% CI; 1.05-2.48). Conclusion: Timely administration of the birth dose vaccines is low in Northern Nigeria. Furthermore, some babies do not get the required vaccines despite presenting for vaccination due to stockout. Strategies for early neonatal vaccination such as vaccination in hospital suites post-delivery and utilizing relatives/fathers to take the baby for vaccination when a mother is indisposed are imperative.

Immunogenicity and safety of routine 13-valent pneumococcal conjugate vaccination outside recommended age range in patients with hematological malignancies and solid tumors.

Hematological malignancy and solid tumor are major risks for invasive pneumococcal disease. Thirteen-valent pneumococcal conjugate vaccine (PCV13) is recommended for immunocompromised patients aged 6 years and older and adults who had not received the vaccine previously. However, vaccination for these individuals is not publicly subsidized in Japan. We measured pneumococcal serotype-specific IgGs (Pn-IgGs) and opsonophagocytic activities (Pn-OPAs) against PCV13 serotypes (1, 3, 5, 6A, 7F, and 19A) in patients with hematological malignancies and solid tumors who were outside the recommended age range for routine vaccination at baseline and at 1 and 6 months after the first dose of PCV13. Pneumococcal serotype-specific memory B cells (Pn-MBCs) against serotype 3 were measured from a portion of the study samples. Thirty-seven patients (30 in the young patient group and 7 in the adult patient group) completed the study. Pn-IgGs were significantly elevated at 1 month post-vaccination and persisted in protection level for 6 months after the first vaccination against all six serotypes measured except serotype 3. Pn-OPAs were significantly elevated and persisted as well against all six serotypes. Pn-MBCs were measured in 10 patients, and 90% of them had at least one detectable Pn-MBC, and 70% of them showed an increased frequency of Pn-MBCs against serotype 3. No serious adverse events were observed up to 1 month after vaccination. PCV13 is thus safe and immunogenic, including against serotype 3, in patients with hematological malignancies and solid tumors outside the recommended age range for routine vaccination.

Understanding the complexity of demand-side determinants on vaccine uptake in sub-Saharan Africa.

Routine vaccination annually prevents millions of deaths worldwide but is underutilized in sub-Saharan Africa (SSA). The complexity of socio-cultural factors impacting vaccine uptake is not well understood. Hence, this paper aims to review the socio-cultural determinants of vaccine uptake and visualize their interrelationships. We conducted a literature search using Pubmed and Embase databases, including articles published from 2000 to 2019 describing socio-cultural demand-side determinants for vaccine uptake. Using the Andersen and Newman Framework of Health Services Utilization, demand-side determinants were categorized as predisposing, enabling or need factors. A qualitative system dynamics approach was employed to visualize how these factors and their dynamic interrelationships influence vaccine uptake. This visualization, by means of a causal-loop diagram (CLD), was mostly based on a qualitative input, with the majority being statements of the authors. These statements were abstracted from the papers found in the review. Quantification was done by counting direct (statistical) associations between each determinant and 'timely and full routine immunization coverage'. A total of 90 articles, primarily from Nigeria (n = 23), Ethiopia (n = 17) and Kenya (n = 11), met the inclusion criteria. We find that maternal autonomy and the perceived benefits caregivers attach to vaccination and exert their influences on many other factors through several feedback loops, thereby influencing timely and full routine immunization coverage. Utilization of health services (supply-related) and access to information (demand-related) were considered as high-potential leverage points. Quantification has shown that maternal autonomy and perceived benefit have an unclear evidence base. Future research should focus on these key players as they play a central role in multiple complex pathways, through which they could influence the uptake of vaccines in SSA.

Addressing an urgent global public health need: Strategies to recover routine vaccination during the COVID-19 pandemic.

Routine vaccination has been severely impacted by the COVID-19 pandemic, with 37% of countries reporting continuing disruptions to vaccination services into 2021. These programs have been faced with the challenges of achieving high vaccination coverage rates (VCRs), as well as identifying and vaccinating those who missed recommended doses since the pandemic began. Declines in VCRs, even for short periods, can lead to an increase in disease outbreaks, place additional pressure on health systems, and leave communities across the world at risk of death and disease from vaccine-preventable diseases.In the face of these disruptions, select governments are implementing promising approaches to address low VCRs, some of which represent innovative solutions to advance short-term, as well as longer-term program improvement. However, expanded action is urgently required to fully recover vaccination programs and strengthen vaccine system infrastructure. The COVID-19 pandemic provides a unique opportunity to modernize routine programs and corresponding infrastructure to meet today's and tomorrow's health challenges more effectively and efficiently. This can be achieved by prioritizing routine vaccination as an essential health service, improving access to vaccination across the life-course, strengthening data systems, ensuring sustainable immunization financing, and building confidence in vaccination.

Effect of evidence updates on key determinants of measles vaccination impact: a DynaMICE modelling study in ten high-burden countries.

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.

Long-term survivors following autologous haematopoetic stem cell transplantation have significant defects in their humoral immunity against vaccine preventable diseases, years on from transplant.

Current international guidelines recommend routinely vaccinating haematopoetic stem cell transplant (HSCT) recipients. Despite significant infection-related mortality following autologous HSCT, routine vaccination programmes (RVP) completion is poor. For recovered HSCT recipients, it is uncertain whether catch-up vaccination remains worthwhile years later. To determine potential susceptibility to vaccine preventable infections, we measured antibody titres in 56 patients, a median of 7 years (range 0-29) following autologous HSCT, who had not completed RVP. We found that almost all participants had inadequate titres against diphtheria (98.2%) and pneumococcal infection (100%), and a significant proportion had inadequate titres against measles (34.5%). Of those subsequently vaccinated according to available guidelines, many mounted adequate serological responses. These data suggest a pragmatic catch-up approach for autologous HSCT recipients who have not completed RVP is advisable, with universal vaccination against some pathogens (e.g. Streptococcus pneumoniae and diphtheria) and serologically-guided approaches for others (e.g. measles and varicella zoster virus).

Impact of COVID-19 on routine immunisation in South-East Asia and Western Pacific: Disruptions and solutions.

BACKGROUND: Data on COVID-19-induced disruption to routine vaccinations in the South-East Asia and Western Pacific regions (SEAR/WPR) have been sparse. This study aimed to quantify the impact of COVID-19 on routine vaccinations by country, antigen, and sector (public or private), up to 1 June 2020, and to identify the reasons for disruption and possible solutions. METHODS: Sanofi Pasteur teams from 19 countries in SEAR/WPR completed a structured questionnaire reporting on COVID-19 disruptions for 13-19 routinely delivered antigens per country, based on sales data, government reports, and regular physician interactions. Data were analysed descriptively, disruption causes ranked, and solutions evaluated using a modified public health best practices framework. FINDINGS: 95% (18/19) of countries reported vaccination disruption. When stratified by country, a median of 91% (interquartile range 77-94) of antigens were impacted. Infancy and school-entry age vaccinations were most impacted. Both public and private sector healthcare providers experienced disruptions. Vaccination rates had not recovered for 39% of impacted antigens by 1 June 2020. Fear of infection, movement/travel restrictions, and limited healthcare access were the highest-ranked reasons for disruption. Highest-scoring solutions were separating vaccination groups from unwell patients, non-traditional vaccination venues, virtual engagement, and social media campaigns. Many of these solutions were under-utilised. INTERPRETATION: COVID-19-induced disruption of routine vaccination was more widespread than previously reported. Adaptable solutions were identified which could be implemented in SEAR/WPR and elsewhere. Governments and private providers need to act urgently to improve coverage rates and plan for future waves of the pandemic, to avoid a resurgence of vaccine-preventable diseases. FUNDING: Sanofi Pasteur.