Early Childhood Vaccination Research Articles

Success in vaccination programming through community health workers: a qualitative analysis of interviews and focus group discussions from Nepal, Senegal and Zambia

ObjectivesCommunity health workers are essential to front-line health outreach throughout low-income and middle-income countries, including programming for early childhood immunisation. Understanding how community health workers are engaged for successful early...

Completion of multidose vaccine series in early childhood: current challenges and opportunities.

Completion of all doses in multidose vaccine series provides optimal protection against preventable infectious diseases. In this review, we describe clinical and public health implications of multidose vaccine series noncompletion, including current challenges to ensuring children receive all recommended vaccinations. We then highlight actionable steps toward achieving early childhood immunization goals. Although coverage levels are high for most early childhood vaccinations, rates of completion are lower for vaccinations that require multiple doses. Recent research has shown that lower family socioeconomic status, a lack of health insurance coverage, having multiple children in the household, and moving across state lines are associated with children failing to complete multidose vaccine series. These findings provide contextual evidence to support that practical challenges to accessing immunization services are impediments to completion of multidose series. Strategies, including reminder/recall, use of centralized immunization information systems, and clinician prompts, have been shown to increase immunization rates. Re-investing in these effective interventions and modernizing the public health infrastructure can facilitate multidose vaccine series completion. Completion of multidose vaccine series is a challenge for immunization service delivery. Increased efforts are needed to address remaining barriers and improve vaccination coverage in the United States.

Maternal worry of children contracting COVID-19 predicts vaccine uptake in young children in Vermont

BackgroundYoung children, 6 months to 4 years of age, were the last population for whom the COVID-19 vaccines became available and remain the group with the lowest uptake. Scarce information exists on drivers of vaccine uptake in young children. The relationship between parental perceived risk of infection and child COVID-19 vaccination is unknown. ObjectiveExamine the association between perceived risk of infection and early childhood vaccination. MethodsIn June 2020, perinatal women in Vermont were enrolled in a longitudinal survey study assessing life changes during the pandemic. Surveys included worry of infection, Parents Attitude about Childhood Vaccines (PACV), intention to vaccinate children with the COVID-19 vaccine, and masking behaviors. Once vaccines became available, surveys also included child vaccination status. A demographic-adjusted stepwise logistic regression was conducted to assess the relationship of worry of infection and vaccine hesitancy on child vaccination status. Results85 women completed baseline and follow up surveys. Participants were highly adherent to adult COVID vaccines with 93 % at least partially vaccinated and only 3 % demonstrated general childhood vaccine hesitancy on the PACV. However, in this highly adherent population, only 61 % of young children are vaccinated. In univariate [OR = 7.35 95 % CI (2.70 to 20.02)] and demographic adjusted [OR = 6.03 95 % CI (1.30 to 27.90)] models, current worry about child infection was associated with higher odds of child vaccination. Previously established predictors, vaccine hesitancy [OR = 0.91 95 % CI (0.84 to 0.99)] and younger maternal age [OR = 1.33 95 % CI (1.07 to 1.65)] were again associated lower odds of child vaccination. ConclusionAmong vaccine adherent parents, worry of infection was a strong predictor of vaccine uptake. Continued efforts to articulate the potential morbidity of COVID in young children, along with established methods to address general vaccine hesitancy may aid in COVID vaccine uptake in this population.

It takes two: The relative contributions of parent versus child-led regulatory behaviours on toddler vaccination pain.

Past research has established the important role of parent soothing in early childhood pain management. However, limited research has assessed children's own emerging emotion regulation strategies to reduce their pain during vaccination. The purpose of the current study was to understand the relative contributions of child-led emotion-regulation behaviours over and above parent regulatory behaviours and pre-needle distress. Toddler-caregiver dyads were videotaped at their 12- and/or 18-month vaccinations. Videos were coded for pain-related behavioural distress, child-led regulatory behaviours (disengagement of attention, parent-focused behaviours, and physical self-soothing), and parent regulatory/soothing behaviours (distraction, physical comfort, rocking, verbal reassurance). Pre-needle distress, followed by parent regulatory behaviours, followed by child regulatory behaviours were used as hierarchical predictors of pain regulation. Two sets of models were estimated at each age, by incorporating parent and child regulatory behaviours at 1 min and 2 min post-needle, separately. At both ages, child-led parent-focused behaviours predicted less regulation. At 18 months, parent soothing behaviours (e.g. distraction, verbal reassurance, rocking) played a stronger role in regulation, however; the only behaviour that increased regulation was rocking. Measuring both parent and child regulatory behaviours was important for fully understanding pain-related distress regulation. Toddlers' use of parent-focused regulatory behaviours (e.g. proximity seeking) suggests that they signal to their parent directly when they are struggling to regulate post-needle. The only parent behaviour that supported this regulation was rocking at 18 months, suggesting a greater need to understand the sensitivity of parent behaviours post-needle. To our knowledge, this is the first study to examine both parent and child regulatory behaviours following vaccination at different stages in toddlerhood. This investigation allows a deeper understanding of the dyadic nature of early childhood vaccination, as well as the evolving role of the parent through toddlerhood. Importantly, findings suggest that toddlers do not simply wait for their parents to respond to their pain post-needle and provide clear signals to show their need of support in regulation.

Factors associated with vaccine coverage improvements in Senegal between 2005 and 2019: a quantitative retrospective analysis

ObjectiveSenegal has demonstrated catalytic improvements in national coverage rates for early childhood vaccination, despite lower development assistance for childhood vaccines in Senegal compared with other low-income and lower-middle income countries....

Vaccine-specific Aspects Associated with the Abandonment of Early Childhood Vaccination in the City of Kisangani, DR Congo

In Kisangani, the dropout rate of 17.5% among children aged 12 to 23 months is higher than the threshold of less than 10% tolerated by the WHO, despite the free availability of vaccines. This study aims to analyze vaccine-specific aspects in order to identify predictors associated with vaccine dropout among children aged 12 to 23 months. A cross-sectional observational study was conducted from October 25, 2022 to February 25, 2023 among mothers of 336 children aged 12 to 23 months in Kisangani. A pre-tested and administered questionnaire was used for data collection based on three-stage cluster sampling. Analyses were performed on STATA 13 using stepwise logistic regression with a threshold of 0.05. A total of 336 children aged 12 to 23 months from 5 health zones in the city of Kisangani were included in the analysis. We observed a 37.5% prevalence of early childhood vaccination drop-out in Kisangani. After adjustment by multivariate logistic regression, the following determinants were significantly associated with drop-out from early childhood vaccination : preference for vaccine administration mode, refusal of a vaccine during a mass campaign, delay in vaccinating when a new vaccine is introduced, lack of confidence in vaccinators who go door-to-door, preference of vaccination site, presence of adverse events following immunization and poor reception by health professionals. Thus, the results of this study can help planners, policy-makers and decision-makers to focus on both individuals and the communities in which they live.

Drivers of early childhood vaccination success in Nepal, Senegal, and Zambia: a multiple case study analysis using the Consolidated Framework for Implementation Research

IntroductionThe fundamental components of a vaccine delivery system are well-documented, but robust evidence is needed on how the related processes and implementation strategies — including the facilitators and barriers — contribute to improvements in childhood vaccination coverage. The purpose of this study was to identify critical facilitators and barriers to the implementation of common interventions across three countries that have dramatically increased coverage of early childhood vaccination over the past 20 years, and to qualify common or divergent themes in their success.MethodsWe conducted 278 key informant interviews and focus group discussions with public health leaders at the regional, district, and local levels and community members in Nepal, Senegal, and Zambia to identify intervention activities and the facilitators and barriers to implementation. We used thematic analysis grounded in the Consolidated Framework for Implementation Research (CFIR) constructs of inner and outer settings to identify immunization program key facilitators and barriers.ResultsWe found that the common facilitators to program implementation across the countries were the CFIR inner setting constructs of (1) networks and communications, (2) goals and feedback, (3) relative priority, and (4) readiness for implementation and outer setting constructs of (5) cosmopolitanism and (6) external policies and mandates. The common barriers were incentives and rewards, available resources, access to knowledge and information, and patients’ needs and resources. Critical to the success of these national immunization programs were prioritization and codification of health as a human right, clear chain of command and shared ownership of immunization, communication of program goals and feedback, offering of incentives at multiple levels, training of staff central to vaccination education, the provision of resources to support the program, key partnerships and guidance on implementation and adoption of vaccination policies.ConclusionAdequate organizational commitment, resources, communication, training, and partnerships were the most critical facilitators for these countries to improve childhood vaccination.

Reduced health care utilization among young children of immigrants after Donald Trump's election and proposed public charge rule.

Widespread fear among immigrants from hostile 2016 presidential campaign rhetoric decreased social and health care service enrollment (chilling effect). Health care utilization effects among immigrant families with young children are unknown. We examined whether former President Trump's election had chilling effects on well-child visit (WCV) schedule adherence, hospitalizations, and emergency department (ED) visits among children of immigrant vs US-born mothers in 3 US cities. Cross-sectional surveys of children <4 years receiving care in hospitals were linked to 2015-2018 electronic health records. We applied difference-in-difference analysis with a 12-month pre/post-election study period. Trump's election was associated with a 5-percentage-point decrease (-0.05; 95% CI: -0.08, -0.02) in WCV adherence for children of immigrant vs US-born mothers with no difference in hospitalizations or ED visits. Secondary analyses extending the treatment period to a leaked draft of proposed changes to public charge rules also showed significantly decreased WCV adherence among children of immigrant vs US-born mothers. Findings indicate likely missed opportunities for American Academy of Pediatrics-recommended early childhood vaccinations, health and developmental screenings, and family support. Policies and rhetoric promoting immigrant inclusion create a more just and equitable society for all US children.

Combating Online Misinformation Regarding Vaccinations

An increasing number of parents refrain from vaccinating their children. This causes lower immunisation coverage, resulting in disease outbreaks. Online misinformation about early-childhood vaccination is a potential cause of this problem. This study tests whether a warning tool, with the appearance of a traffic light, can influence parents’ information choices. An online experiment was conducted with parents and expecting parents (N = 179) with varying pre-existing attitudes and in different decision stages. Participants were asked to select three vaccine-related web links on a Google search result page either with or without the warning tool present. Results showed that participants in the warning tool condition (i.e., who saw reliability labels) selected a higher number of links marked as reliable compared to participants in the control group. No significant moderating effect of decision stage and pre-existing attitude were found. As our findings suggest that a warning tool can lead to better-informed vaccination decisions, the implementation of such a warning tool may prove worthwhile.

Childhood Vaccination Practices and Parental Hesitancy Barriers in Rural and Urban Primary Care Settings.

The purpose of our study was to identify primary care providers' (PCPs') practices in promoting childhood vaccination and their perceptions regarding barriers to vaccination in a primarily rural state. In January-May 2022, we conducted a mail and online survey of PCPs across Montana (n = 829). The survey included modules on routine immunizations in children 0-2 years old and COVID-19 vaccination in children 5-17 years old. The survey response rate was 36% (298/829). We categorized PCPs as working in rural (n = 218) or urban areas (n = 80), based on Rural-Urban Commuting Area codes. We then compared responses between rural and urban PCPs using chi-square tests. Urban PCPs (90-94%, depending on vaccine) stocked routinely recommended vaccines more frequently than rural PCPs (71-84%), but stocked the COVID-19 vaccine less often than rural PCPs (44% vs. 71%, respectively, p < 0.001). A higher percentage of rural providers reported parental beliefs that vaccine-preventable diseases are not severe enough to warrant vaccination (48% vs. 31%, p = 0.01) and concerns that vaccination will weaken their child's immune system (29% vs. 6%, p < 0.001). More rural (74%) compared to urban (59%) PCPs identified a social media campaign from local health departments promoting early childhood vaccinations as an effective strategy to increase childhood vaccination rates (p = 0.01). We identified key differences in some childhood vaccination practices and barriers between rural and urban PCPs. Interventions to increase rural vaccination rates could include increasing the number of providers stocking all recommended vaccines, identifying strategies to address parents' concerns regarding vaccine necessity, and collaborations with public health departments.

Locating vaccine uptake and public participation in Ukraine: An exploratory qualitative study on attitudes and barriers to early childhood vaccination

ABSTRACT A growing body of literature on vaccine hesitancy considers context and the intersecting factors affecting vaccine uptake. This study attempts to add focus to the conversation of vaccines in Ukraine by exploring how vaccines are perceived and how local stakeholders envision solutions to the problems surrounding vaccine uptake. Twenty-five in-depth interviews were carried out among parents of children under 6 years of age as well as health practitioners and other experts in Ukraine. Results were presented to stakeholders during a dialogue session to discuss the implications for policy recommendations. The Roma parents interviewed faced structural barriers to vaccine access, while other groups received vaccine information from others in their communities, such as family members or religious organisations. Mistrust of the health system and lack of access to reliable information preceded many doubts parents expressed surrounding vaccines. Stakeholders agreed that better, more targeted communication strategies are needed, as well as increased engagement with and training of medical practitioners. Qualitative methods allowed for a deeper, more nuanced understanding of the factors contributing to low vaccine uptake, of which vaccine hesitancy is only one part. The vulnerability-informed approach used may have broader applications for community engagement and responding to infectious diseases and crises.

Beyond Vaccination Coverage: Population-Based Measurement of Early Childhood Immunization Schedule Adherence.

The immunization schedule recommended by the U.S. Advisory Committee on Immunization Practices (ACIP) provides a structure for how 10 different vaccine series should be administered to children in the first 18 months of life. Progress toward US early childhood immunization goals has largely focused on measuring vaccination coverage at age 24 months. However, standard vaccination coverage measures do not reflect whether children received vaccine doses by recommended ages, or whether vaccines were given concomitantly, per the schedule. In this paper, we describe innovations in population-level measurement of immunization schedule adherence through quantifying vaccination timeliness and undervaccination patterns. Measuring vaccination timeliness involves comparing when children received vaccine doses relative to ACIP age recommendations. To assess undervaccination patterns, children's vaccination histories are analyzed to determine whether they were vaccinated consistent with the ACIP schedule. Some patterns, such as spreading out vaccines across visits, are indicative of parental hesitancy. Other patterns, such as starting all recommended series but missing doses, are largely indicative of other immunization services delivery challenges. Since 2003, at least 12 studies have used National Immunization Survey-Child, immunization information system, or integrated health plan data to measure vaccination timeliness or undervaccination patterns at national or state levels. Moving forward, these novel measures can be leveraged for population-based surveillance of vaccine confidence, and for distinguishing undervaccination due to parental vaccine hesitancy from undervaccination due to other causes. Broader adoption of these measures can facilitate identification of targeted strategies for improving timely and routine early childhood vaccination uptake across the United States.

109. Seroprevalence of Protective Antibodies against Varicella, Hepatitis-A and Dengue among Indian Children, Adolescents and Adults

Abstract Background Varicella, Hepatitis-A and Dengue cause significant disease burden in our country. Estimation of age-wise seroprevalence of antibodies against these diseases not only help us in understanding age-specific incidence rates and susceptibility, but also help policy makers in deciding need and timing of vaccination. None of these vaccines are part of current national immunization program in India, yet. Methods In this observational cross-sectional study, apparently healthy children (9-12 years), adolescents (15-18 years) and adults (25-30 years) attending OPD of a tertiary care hospital in Northern India over two-year period (July 17- June 19) were enrolled after taking informed written consent, and their 3-ml venous blood sample was collected. Ethical clearance was obtained from Institute Ethics committee, before enrolling subjects. Serum was tested for IgG antibodies using specific commercial ELISA kits. Those who received received Hepatitis-A or Varicella vaccination in past were excluded from enrollment. Results Out of total 240 subjects (M:F=117:123) enrolled, 75 were children, 75 adolescents and 90 adults in specified age groups. Mean age in these three groups were 11.04, 16.52 and 26.53 years respectively. In our study, antibodies (IgG) against Varicella were &amp;gt;12 U/ml (seroprotective) in 36% (27/75), 74.6% (56/75), 64.5% (58/90) in children, adolescent and adults in specified age groups, respectively. Similarly, the antibodies (IgG) against Hepatitis-A were &amp;gt;10 U/ml (seroprotective) in above three groups were 68% (51/75), 85.3% (64/75), 95.5% (86/90). For dengue IgG antibodies also, seropositivity rates in above three groups were 37.3% (28/75), 62.7% (47/75), 53.3% (48/90). Conclusion Large proportion of children, adolescents and adults remain susceptible to Varicella and Hepatitis-A infection in India. Early childhood vaccination with Varicella and Hepatitis-A vaccines should be a part of National Immunization Programme in India, as a part of preventive strategy. Our study also showed a large proportion of children, adolescents and adults remain seronegative for Dengue antibodies in various age groups. Therefore, if currently available dengue vaccine (Dengvaxia) has to be used in our population, it can only be used after individual screening. Disclosures All Authors: No reported disclosures.

Association of parent influenza vaccination and early childhood vaccinations using linked electronic health record data

IntroductionParent and child vaccination behavior is related for human papillomavirus (HPV) and flu vaccine. Thus, it is likely that parental vaccination status is also associated with their children’s adherence to guideline-concordant childhood vaccination schedules. We hypothesized that parent influenza (flu) vaccination would be associated with their child’s vaccination status at age two. MethodsWe used electronic health record data to identify children and linked parents seen in a community health center (CHC) within the OCHIN network (292 CHCs in 16 states). We randomly selected a child aged <2 years with ≥1 ambulatory visit between 2009-2018.Employing a retrospective, cohort study design, we used general estimating equations logistic regression to estimate the odds of a child being up-to-date on vaccinations based on their linked parents’ flu vaccination status. We adjusted for relevant parent and child covariates and stratified by mother only, father only, and two-parent samples. ResultsThe study included 40,007 family-units: mother only = 35,444, father only = 2,784, and two parents = 1,779. A higher percentage of children were fully vaccinated if their parent or parents received a flu vaccine. Children in the two-parent sample whose parents both received a flu vaccine had more than twice the odds of being fully vaccinated, and two and a half times the odds of being fully vaccinated except flu vaccine compared to children with two parents who did not receive a flu vaccine (covariate-adjusted odds ratio [aOR] = 2.39, 95% CI = 1.67, 3.43 and aOR = 2.54, 95% CI = 1.54, 4.19, respectively). ConclusionsParent flu vaccination is associated with routine child vaccination. Future research is needed to understand if this relationship persists over time and in different settings.

Community health worker intervention improves early childhood vaccination rates: results from a propensity-score matching evaluation

BackgroundArizona’s Health Start Program is a statewide community health worker (CHW) maternal and child health home visiting intervention. The objective of this study was to test if participation in Health Start during 2006–2016 improved early childhood vaccination completion rates.MethodsThis retrospective study used 11 years of administrative, birth certificate, and immunization records. Propensity score matching was used to identify control groups, based on demographic, socioeconomic, and geographic characteristics. Results are reported by historically disadvantaged subgroups and/or with a history of low vaccine uptake, including Hispanic/Latinx and American Indian children, and children of low socioeconomic status and from rural areas, children with teen mothers and first-born children. The average treatment-on-the-treated (ATT) effect estimated the impact of Health Start on timely completion of seven early childhood vaccine series: diphtheria/tetanus toxoids and acellular/whole-cell pertussis (DTaP/DTP), Haemophilus influenzae type b (Hib), hepatitis B (Hep. B), measles-mumps-rubella (MMR), pneumococcal conjugate vaccine (PCV13), poliovirus, and varicella.ResultsVaccination completion rates (by age five) were 5.0% points higher for Health Start children as a group, and on average 5.0% points higher for several subgroups of mothers: women from rural border counties (ATT 5.8), Hispanic/Latinx women (ATT 4.8), American Indian women (ATT 4.8), women with less than high school education (ATT 5.0), teen mothers (ATT 6.1), and primipara women (ATT 4.5), compared to matched control groups (p-value ≤ 0.05). Time-to-event analyses show Health Start children complete vaccination sooner, with a hazard rate for full vaccination 13% higher than their matches.ConclusionA state-operated home visiting intervention with CHWs as the primary interventionist can effectively promote early childhood vaccine completion, which may reduce the incidence of preventable diseases and subsequently improve children’s health. Effects of CHW interventions on vaccination uptake is particularly relevant given the rise in vaccine-preventable diseases in the US and globally.Trial registrationApproved by the University of Arizona Research Institutional Review Board (Protocol 1701128802), 25 January 2017.

Impact of the COVID-19 pandemic on vaccine coverage for early childhood vaccines in Alberta, Canada: a population-based retrospective cohort study

ObjectiveTo assess the impact of the COVID-19 pandemic on early childhood vaccination coverage in Alberta, Canada.SettingAlberta, a western Canadian province, which has a population of 4.4 million and approximately 50...

Routine childhood vaccination rates in an academic family health team before and during the first wave of the COVID-19 pandemic: a pre-post analysis of a retrospective chart review.

Background:There has been concern about declining routine vaccination rates during the COVID-19 pandemic. We evaluated the impact of the COVID-19 pandemic on early childhood vaccination rates at 2 sites of an academic family health team in the Greater Toronto Area, Ontario, serving both an urban and suburban patient population.Methods:We conducted a pre–post analysis of vaccination records from Jan. 1, 2018, to Nov. 30, 2020, for a cohort of children born between Jan. 1, 2018, and Aug. 31, 2020, from the electronic medical record (EMR) of the Mount Sinai Academic Family Health Team (including an urban academic site in Toronto and a suburban community site in Vaughan, Ontario). We estimated the proportion of children receiving timely, delayed or no vaccination for 10 publicly funded vaccines in the Ontario immunization schedule for the pre-COVID-19 (Jan. 1, 2018, to Mar. 16, 2020) and COVID-19 (Mar. 17 to Nov. 30, 2020) pandemic periods. We determined timeliness in accordance with the recommended age of administration, with a 28-day window; we considered vaccines administered after this window to be delayed. We estimated the median time to vaccination for each vaccine and present cumulative incidence curves.Results:The patient population was balanced between boys (52.4%) and girls (47.6%), with an average age of 18.5 months and representation across low-, middle- and high-income groups. Of the 506 children in our cohort, 422 were up to date with vaccinations (83.4%) by the end of the study period. Comparatively, 308 (83.2%) of the 370 eligible patients were up to date for all required vaccinations by the end of the pre-COVID-19 period. Among children younger than 12 months, vaccination rates were similar in the pre-COVID-19 and COVID-19 pandemic periods. Lower rates of timely vaccination for children between 12 and 18 months of age were amplified during the pandemic. Cumulative incidence curves were suggestive of a decrease in the timeliness of vaccinations in the COVID-19 period for the vaccines administered at 12, 15 and 18 months, compared with the pre-COVID-19 period.Interpretation:Our local findings suggest a deterioration in the uptake of routine childhood vaccines in children aged 12 to 18 months in the first year of the COVID-19 pandemic. Further study is needed to determine the extent of the vaccination gap in children across Canada, including the impact of subsequent waves of the COVID-19 pandemic.

Vaccine timeliness and prevalence of undervaccination patterns in children ages 0–19 months, U.S., National Immunization Survey-Child 2017

ObjectivesTypically, early childhood vaccination coverage in the U.S. is measured as the proportion of children by age 24 months who completed recommended vaccine series. However, these measures do not reflect whether vaccine doses were received at the ages recommended by the U.S. Advisory Committee on Immunization Practices, or whether children received vaccines concomitantly, per the ACIP recommended schedule. This study’s objective was to quantify vaccine timeliness and prevalence of specific patterns of undervaccination in U.S. children ages 0–19 months. MethodsUsing 2017 National Immunization Survey-Child data, we calculated days undervaccinated for the combined 7-vaccine series and distinguished undervaccination patterns indicative of parental vaccine hesitancy, such as spreading out vaccines across visits (“shot-limiting”) or starting some but not all recommended vaccine series (“selective vaccination”), from other non-hesitancy patterns, such as missing final vaccine doses or receiving all doses, with some or all late. We measured associations between demographic, socioeconomic and other characteristics with undervaccination patterns using multivariable log-linked binomial regression. Analyses accounted for the complex survey design. ResultsAmong n = 15,333 U.S. children, only 41.2% received all recommended vaccine doses on-time by age 19 months. Approximately 20.9% of children had an undervaccination pattern suggestive of parental vaccine hesitancy, and 36.2% had other undervaccination non-hesitancy patterns. Uninsured children and those with lower levels of maternal education were more likely to exhibit undervaccination patterns suggestive of parental hesitancy. Lower levels of maternal education were also associated with other non-hesitancy undervaccination patterns. ConclusionsMore than half of children in the U.S. are undervaccinated at some point by 19 months of age. Ongoing assessment of vaccine timeliness and immunization schedule adherence could facilitate timely and targeted public health interventions in populations with high levels of undervaccination.

BCG Vaccination in Early Childhood and Risk of Atopic Disease: A Systematic Review and Meta-Analysis.

Background Several large-scale studies suggest that Bacille Calmette–Guerin (BCG) vaccination in early childhood may reduce the risk of atopic diseases, but the findings remain controversial. Here, we aimed to investigate the potential correlation between early childhood BCG vaccination and the risk of developing atopic diseases. Methods Eligible studies published on PubMed, EMBASE, and Cochrane CENTRAL were systematically sourced from 1950 to July 2021. Studies with over 100 participants and focusing on the association between BCG vaccine and atopic diseases including eczema, asthma, and rhinitis were included. Preliminary assessment of methods, interventions, outcomes, and study quality was performed by two independent investigators. Odds ratio (OR) with 95% confidence interval (CI) was calculated. Random effects of the meta-analysis were performed to define pooled estimates of the effects. Results Twenty studies with a total of 222,928 participants were selected. The quantitative analysis revealed that administering BCG vaccine in early childhood reduced the risk of developing asthma significantly (OR 0.77, 95% CI 0.63 to 0.93), indicating a protective efficacy of 23% against asthma development among vaccinated children. However, early administration of BCG vaccine did not significantly reduce the risk of developing eczema (OR 0.94, 95% CI 0.76 to 1.16) and rhinitis (OR 0.99, 95% CI 0.81 to 1.21). Further analysis revealed that the effect of BCG vaccination on asthma prevalence was significant especially in developed countries (OR 0.73, 95% CI 0.58 to 0.92). Conclusion BCG vaccination in early childhood is associated with reduced risk of atopic disease, especially in developed countries.

Hepatitis B virus infection and hepatocellular carcinoma in sub-Saharan Africa: Implications for elimination of viral hepatitis by 2030?

Elimination of viral hepatitis in sub-Saharan Africa by 2030 is an ambitious feat. However, as stated by the World Health Organization, there are unprecedented opportunities to act and make significant contributions to the elimination target. With 60 million people chronically infected with hepatitis B virus (HBV) of whom 38800 are at risk of developing highly fatal hepatocellular carcinoma (HCC) every year, sub-Saharan Africa faces one of the greatest battles towards elimination of viral hepatitis. There is a need to examine progress in controlling the disproportionate burden of HBV-associated HCC in sub-Saharan Africa within the context of this elimination target. By scaling-up coverage of hepatitis B birth dose and early childhood vaccination, we can significantly reduce new cases of HCC by as much as 50% within the next three to five decades. Given the substantial reservoir of chronic HBV carriers however, projections show that HCC incidence and mortality rates in sub-Saharan Africa will double by 2040. This warrants urgent public health attention. The trends in the burden of HCC over the next two decades, will be determined to a large extent by progress in achieving early diagnosis and appropriate linkage to care for high-risk chronic HBV infected persons.