Vaccination inequities among children 12-23 months in India: An analysis of inter-state differences.

Background: Previous research has shown that socioeconomic and demographic risk factors in children are additive and lead to increasingly negative impacts on vaccination coverage. The goal of this study is to examine if different combinations of four risk factors (infant sex, birth order, maternal education level, and family wealth status) vary by state among children 12-23 months in India and to determine the impact of ≥ 1 risk factor on differences in state vaccination rates. Methods: Using data from the National Family Health Survey (NFHS) conducted in India between 2005 and 2006 (NFHS-3) and 2015-2016 (NFHS-4), full vaccination of children 12-23 months was examined. Full vaccination was defined as receipt of one dose of bacillus Calmette-Guérin (BCG), three doses of diphtheria-pertussis-tetanus vaccine (DPT) vaccine, three doses of oral polio vaccine (OPV), and one dose of measles-containing vaccine (MCV). Associations between full vaccination and the four risk factors were assessed using logistic regression. Data were analyzed by the state of residence. Results: A total of 60.9% of children 12-23 months were fully vaccinated, in NFHS-4, ranging from 33.9% in Arunachal Pradesh to 91.3% in Punjab. In NFHS-4, the odds of full vaccination across all states were 15% lower among infants with 2 risk factors versus 0 or 1 risk factors (OR: 0.85, 95% CI: 0.80-0.91), and 28% lower among infants with 3 or 4 risk factors versus 0 or 1 risk factor (OR: 0.72, 95% CI: 0.67-0.78). Overall, the absolute difference in the full vaccination coverage in those with > 2 vs < 2 risk factors decreased from -13% in NFHS-3 to -5.6% in NFHS-4, with substantial variation across states. Conclusions: Disparities in full vaccination exist among children 12-23 months experiencing > 1 risk factor. Indian states that are more populous or located in the north were more likely to have greater disparities.

Impact of the national hepatitis B immunization program in China: a modeling study.

BACKGROUND: Elimination of hepatitis B virus (HBV) is a striking challenge for countries with high or moderate disease burden. Therefore, using China as a practical case to share experiences for similar countries may accelerate the achievement of the WHO 2030 target of 90% reduction in HBV-related incidence. We aim to evaluate the impact of national HBV immunization strategies in China; and the feasibility to achieve WHO 2030 targets under different scenarios. METHODS: We constructed an expanded Susceptible-Exposed-Infectious-Recovered (SEIR) model and decision tree-Markov model to estimate the epidemic of HBV in China, assess the feasibility of 2030 Elimination Goals through the projections and conduct the economic analysis. Least square method was used to calibrate the expanded SEIR model by yearly data of laboratory-confirmed HBV cases from 1990 to 2018. Two models were separately used to evaluate the impact and cost-effectiveness of HBV vaccine by comparing prevalence of chronic HBV infections, quality-adjusted life-years (QALYs), incremental cost effectiveness ratio and benefit-cost ratio (BCR) under various intervention options, providing a basis for exploring new containment strategies. RESULTS: Between 1990 and 2020, the number of chronic HBV infections decreased by 33.9%. The current status quo would lead to 55.73 million infections (3.95% prevalence) in 2030, compared to 90.63 million (6.42% prevalence) of the "Without the NIP" scenario (NIP: National Immunization Program), 114.78 million (8.13% prevalence) without any interventions. The prevention of mother to child transmission (PMTCT) strategy showed a net benefit as 12,283.50 dollars per person, with BCR as 12.66, which is higher than that of universal vaccination at 9.49. Compared with no screening and no vaccination, the PMTCT strategy could save 7726.03 dollars for each QALY increase. CONCLUSIONS: Our findings proved the HBV vaccination has demonstrated a substantial positive impact on controlling the epidemic of HBV in terms of effectiveness and economy after about 30 years of implementation of the national hepatitis B immunization program which also provided containment experience for high or medium burden countries. As for China, the next step should focus on exploring strategies to improve diagnosis and treatment coverage to reduce the burden of HBV-related deaths and ultimately eliminate HBV.

The association of religion with maternal and child health outcomes in South Asian countries.

OBJECTIVE: Theological beliefs play an important role in cultural norms and could impact women's prenatal and postpartum decisions in South Asia, which has a high burden of disease in children and pregnant women. The aim of this study is to identify any associations religion may have in affecting a woman's decision-making ability, and how that in turn affects maternal and child health, at a group level in multiple South Asian countries. STUDY DESIGN: Cross-sectional study utilizing secondary data analysis. METHODS: We used Demographic and Health Surveys (DHS) between 2014 and 2018 in Afghanistan, Bangladesh, India, Maldives, Myanmar, Nepal, and Pakistan. Not every country's survey asked about religion, so we imputed these results based on Census data. We assessed maternal and child health through a composite coverage index (CCI), which accounts for family planning, attendance of a skilled attendant at birth, antenatal care, BCG vaccinations, 3 doses of diphtheria-tetanus-pertussis vaccine, measles vaccine, oral rehydration therapy, and seeking care if the child has pneumonia. The relationship between religion, women's empowerment, and CCI was assessed through linear regression models. RESULTS: The sample included 57,972 mothers who had children aged 12-23 months. CCI is observed to be affected by family income, in addition to religion and country. CCI was higher in Hindus (2.8%, 95% CI: 2.4%, 3.1%) and Buddhists (2.0%, 95% CI: 1.2%, 2.9%) than Muslims. Mother's age, education, income, decision-making autonomy, and attitude towards beatings were all related to CCI. In a model stratified by religion, age, education, and income were significant predictors of CCI for both Muslims and non-Muslims, but were more impactful among Muslims. CONCLUSION: Though multiple imputation had to be used to fill in gaps in religion data, this study demonstrates that maternal and child health outcomes continue to be a concern in South Asia, especially for Muslim women. Given the importance of religious beliefs, utilizing a simple indicator, such as the CCI could be helpful for monitoring these outcomes and provides a tangible first step for communities to address gaps in care resulting from disparities in maternal empowerment.

Women's Empowerment and Child Vaccination in Kenya: The Modifying Role of Wealth.

INTRODUCTION: Although vaccination coverage is high in Kenya relative to other African nations, undervaccinated children remain, making it important to identify characteristics of these children and their caregivers. Potentially relevant but understudied factors are women's empowerment and early marriage. Women who marry older and have more autonomous decision-making authority may be better able to ensure their children receive health services, including immunizations. This analysis examines the relationship between early marriage and multiple dimensions of women's empowerment and child vaccination status in Kenya and explores whether these relationships are modified by wealth. METHODS: Data were from the 2014 Kenya Demographic and Health Survey. The analysis was completed in 2020 using updated data made available to researchers in 2019. Logistic regressions assessed relationships among early marriage, 3 dimensions of women's empowerment (enabling conditions, intrinsic agency, and instrumental agency), and child vaccination. Analyses were stratified by wealth to explore potential effect modification. RESULTS: For women in the middle wealth tertile, the odds of having a fully vaccinated child were 3.45 (95% CI=1.51, 7.91) times higher for those with higher versus lower empowerment. Further, among the wealthiest women, those with middle empowerment were 5.99 (95% CI=2.06, 17.40) times more likely to have a fully vaccinated child than women with lower empowerment. CONCLUSIONS: Results suggest a threshold effect of wealth's role in the relationship between empowerment and vaccination. Enabling conditions may not influence immunization among the poorest women but exert a stronger positive influence on childhood vaccination among wealthier women. SUPPLEMENT INFORMATION: This article is part of a supplement entitled Global Vaccination Equity, which is sponsored by the Global Institute for Vaccine Equity at the University of Michigan School of Public Health.

Vaccine Hesitancy and Concerns About Vaccine Safety and Effectiveness in Shanghai, China.

INTRODUCTION: Rapidly urbanizing communities in middle-income countries could be sources of vaccine hesitancy, and may create hot spots of low vaccination coverage. This study characterizes vaccine hesitancy in Shanghai and identifies disparities in vaccine safety and efficacy concerns by residency status-a marker for recent migration into the city. METHODS: Parents of children aged ≤18 years from immunization clinics in Shanghai were enrolled in summer 2019, with the data analyzed during winter 2019-2020. The paper questionnaire used the Parental Attitudes towards Childhood Vaccines scale, which included questions about vaccine safety and efficacy concerns. The primary independent variable was residency-whether an individual was a Shanghai local or a recent migrant (i.e., non-local). Linear regression models assessed the relationship between residency and vaccine safety and efficacy concerns. RESULTS: Among 1,021 participants, 65.4% had local residency, and the remainder were urban non-locals (13.1%) or rural non-locals (21.5%). A majority of parents expressed concerns about vaccine side effects (73.8%), vaccine safety (63.9%), and vaccine effectiveness (52.4%). Compared with locals, rural non-locals were more concerned about vaccine side effects (ß=0.26, 95% CI=0.07, 0.46), vaccine safety (ß=0.42, 95% CI=0.19, 0.65), and vaccine effectiveness (ß=0.37, 95% CI=0.16, 0.58). CONCLUSIONS: Differences in vaccine hesitancy by residency could lead to geographical and sociodemographic disparities in vaccination coverage and outbreaks of vaccine-preventable disease. SUPPLEMENT INFORMATION: This article is part of a supplement entitled Global Vaccination Equity, which is sponsored by the Global Institute for Vaccine Equity at the University of Michigan School of Public Health.

Impact of economic disruptions and disease experiences on COVID-19 vaccination uptake in Asia: A study in Malaysia.

During the coronavirus disease 2019 (COVID-19) pandemic, individuals have had a variety of experiences with the disease and economic disruptions in Asia. We assessed how these experiences could impact COVID-19 vaccination intent and uptake in one of the Asian country, Malaysia. Two opt-in internet-based cross-sectional samples were collected: a March wave (26 March - 7 April 2021) and a June wave (22 June - 10 July 2021). Individuals were asked about their vaccination status, their employment status, and their experience with COVID-19 cases. The impact of economic disruptions and experiences with COVID-19 on COVID-19 vaccination was assessed through a multivariable, multinomial logistic regression model. Among 1,493 participants (735 in March and 758 in June wave), 26% were already vaccinated, 57% planned to vaccinate, and 17% had no plan to vaccinate. The number who had lost a job or earned less because of the pandemic was 30% in March and 36% in June. Across both waves, 5%-6% had a personal, very serious experience of COVID-19, 13%-16% knew of a family member or friend with a very serious experience of COVID-19, and 43%-61% knew of a very serious COVID-19 case through media. Notably, compared to those who worked the same amount throughout the pandemic, those who lost their job had lower odds of already being vaccinated (OR: 0.37; 95%CI: 0.23, 0.59), but similar odds of planning to become vaccinated. Personal, family/friend, and media experiences were also all related to increased odds of planning to vaccinated or being already vaccinated. The COVID-19 pandemic has led to large disruptions in people's lives. People's experiences during the pandemic impact their likelihood of being vaccinated or planning to vaccinate against COVID-19. Equitable allocation of COVID-19 vaccines will require outreach to groups with less stable employment and can leverage people's experiences with disease during the pandemic.

Willingness-to-pay for a COVID-19 vaccine and its associated determinants in Indonesia.

How countries, particularly low- and middle-income economies, should pay the coronavirus disease 2019 (COVID-19) vaccine is an important and understudied issue. We undertook an online survey to measure the willingness-to-pay (WTP) for a COVID-19 vaccine and its determinants in Indonesia. The WTP was assessed using a simple dichotomous contingent valuation approach and a linear regression model was used to assess its associated determinants. There were 1,359 respondents who completed the survey. In total, 78.3% (1,065) were willing to pay for the COVID-19 vaccine with a mean and median WTP of US$ 57.20 (95%CI: US$ 54.56, US$ 59.85) and US$ 30.94 (95%CI: US$ 30.94, US$ 30.94), respectively. Being a health-care worker, having a high income, and having high perceived risk were associated with higher WTP. These findings suggest that the WTP for a COVID-19 vaccine is relatively high in Indonesia. This WTP information can be used to construct a payment model for a COVID-19 vaccine in the country. Nevertheless, to attain higher vaccine coverage, it may be necessary to partially subsidize the vaccine for those who are less wealthy and to design health promotion materials to increase the perceived risk for COVID-19 in the country.

Measles vaccination of young infants in China: A cost-effectiveness analysis.

BACKGROUND: Although global progress in measles control has been realized, achieving elimination has proven difficult in many regions of the world. China has adopted a goal of measles elimination but recent outbreaks predominantly affecting children <8 months who are ineligible for vaccination and incompletely protected by maternal antibodies has impeded progress. We assess the cost-effectiveness of adding an initial measles vaccine dose in China to earlier than the currently recommended 8 months of age. METHODS: We conducted a cost-utility analysis comparing the costs and health benefits associated with adding a measles vaccine dose to the routine schedule at 4, 5, 6 or 7 months compared to the current recommendation for the first dose at age 8 months. A decision analytic model was developed in Microsoft Excel, including five non-severe and two fatal health outcomes associated with measles infection. Model parameters were informed by the literature and surveillance data. Future costs and health benefits were discounted at 3%. Primary outcomes included costs, Quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER) over a lifetime time horizon. RESULTS: Lowering the recommended age for initiating the measles vaccination series to address susceptibility in children <8 months provided incremental health gains compared to minimal costs at the individual-level. The ICER was most favorable ($232.70 per QALY gain) for administering an initial dose at 4 months of age due to fewer incremental program costs when shifting measles administration to an immunization visit already established under the Chinese vaccination program. CONCLUSION: We found potential beneficial health gains at a minimum cost associated with adding an earlier measles dose <8 months of age in China. Further investigation about disease transmission dynamics is required to more fully assess the tradeoffs of administering measles at a younger age to infants in China.

Socioeconomic characteristics associated with the introduction of new vaccines and full childhood vaccination in Ghana, 2014.

BACKGROUND: Childhood vaccination in Ghana has historically been high, but the impact of recently introduced vaccines on coverage is unknown. We calculate vaccine coverage of Ghanaian children- contrasting newly introduced vaccines and those long available - and describe associations between sociodemographic indicators and full vaccination. METHODS: Data from the 2014 Ghana Demographic and Health Survey was used to calculate full vaccination, defined as receipt of one dose bacillus Calmette-Guérin (BCG); two doses of rotavirus vaccine; 3 doses of pentavalent vaccine, oral polio vaccine (OPV), and pneumococcal conjugate vaccine (PCV); and one dose of measles-rubella vaccine and yellow fever vaccine, among children age 12-24 months. Logistic regression with survey procedures was used to estimate odds ratios for socioeconomic factors' association with full vaccination. RESULTS: The sample comprised a total of 1107 children 12-24 months. Full vaccination coverage was 70.8%. Vaccination coverage was higher for vaccines administered at younger ages (e.g., birth dose of BCG was 97.0%) than at older ages (e.g., yellow fever at 9 months was 88.2%). Newly introduced vaccines had lower coverage: at 10 weeks, pentavalent 2 was 95.4%, versus 91.2% for PCV 2 and 88.8% for rotavirus 2. Living outside of Greater Accra, home delivery, younger maternal age, urban residence, and more than one child under five in the home were all associated with decreased odds of full vaccination in the adjusted analysis whereas sex of the child, wealth, religion, and maternal education were not associated with full vaccination status. CONCLUSION: Ghana has high overall vaccination rates although disparities in full vaccination by sociodemographic status exist. As vaccine recommendations are revised, it will be important to insure equitable access to vaccination for all children regardless of demographic and socioeconomic background.

Knowledge of human monkeypox viral infection among general practitioners: a cross-sectional study in Indonesia.

After the first, imported, laboratory-confirmed case of monkeypox in human was reported in Singapore on May 2019, countries in Asia started to strengthen disease surveillance systems. One challenge in preventing monkeypox is a lack of knowledge, particularly among healthcare workers. The aim of this study was to assess the knowledge of monkeypox among general practitioners (GPs) in Indonesia. A cross-sectional online survey was conducted. The survey collected participants' knowledge on a 21-item scale and explanatory variables. A two-step logistic regression analysis was employed to assess the predictors of knowledge of monkeypox. A total of 432 GPs were included; 10.0% and 36.5% of them had a good knowledge using an 80% and 70% cutoff point for knowledge domain, respectively. No explanatory variables were associated with knowledge when using 80% cutoff point. Using the lower cutoff, there was lower knowledge among GPs who graduated from universities located in Sumatra or other islands versus Java (adjusted odds ratio (aOR): 0.53; 95%CI: 0.28-0.97, p = 0.041) and among those were older than 30 years compared to younger GPs (aOR: 0.61; 95%CI: 0.39-0.96, p = 0.033). GPs working in private clinics had less knowledge compared to GPs in community health centers (aOR: 0.55; 95%CI: 0.31-0.99, p = 0.047). In conclusion, knowledge of monkeypox among GPs in Indonesia is relatively low in all groups. Increasing knowledge of monkeypox will be key to improving the capacity of GPs to respond to human monkeypox cases and to report into a disease surveillance system.

Demographics of Vaccine Hesitancy in Chandigarh, India.

The impact of vaccine hesitancy on childhood immunization in low- and middle-income countries remains largely uncharacterized. This study describes the sociodemographic patterns of vaccine hesitancy in Chandigarh, India. Mothers of children <5 years old were sampled from a two-stage cluster, systematic sample based on Anganwadi child care centers in Chandigarh. Vaccine hesitancy was measured using a 10-item Vaccine Hesitancy Scale, which was dichotomized. A multivariable logistic regression assessed the association between socioeconomic factors and vaccine hesitancy score. Among 305 mothers, >97% of mothers thought childhood vaccines were important, effective, and were a good way to protect against disease. However, many preferred their child to receive fewer co-administered vaccines (69%), and were concerned about side effects (39%). Compared to the "other caste" group, scheduled castes or scheduled tribes had 3.48 times greater odds of vaccine hesitancy (95% CI: 1.52, 7.99). Those with a high school education had 0.10 times the odds of vaccine hesitancy compared to those with less education (95% CI: 0.02, 0.61). Finally, those having more antenatal care visits were less vaccine hesitant (≥4 vs. <4 visits OR: 0.028, 95% CI: 0.1, 0.76). As India adds more vaccines to its Universal Immunization Program, consideration should be given to addressing maternal concerns about vaccination, in particular about adverse events and co-administration of multiple vaccines.

Profit considerations in vaccine safety-related events in China.

Objectives: China has made remarkable achievements in the field of immunization. However, several widespread vaccine safety-related events have recently received worldwide attention and reflect flaws in vaccine management. This study aimed to summarize vaccine safety-related events between 1985 and 2018 in China and analyze the profit motives of these events.Methods. Literature and media reviews were conducted to discover vaccine safety-related events. We developed a conceptual model with profit-related variables, and using information available from each event, we identified which profit-related variable was implicated, and how it related to the pursuit of higher profits.Results: A total of 39 vaccine safety-related events were found in vaccine production, procurement, transportation, and daily management, along with adverse events following immunization (AEFIs). Overall, 90% (35/39) of the events could be classified as profit-driven. The motives of most events could be tied to one or more reasons, including decreasing costs among vaccine producers (67%, 26/39), reducing actual procurement price (67%, 26/39), and reducing costs of transportation and/or cold chain (24/39, 62%).Conclusions: In order to deal with vaccine-related challenges, a more restrictive supervision system on vaccine production and more emergency preparedness, including health and risk communication strategies, for vaccine safety should be implemented.

Hepatitis E vaccine in China: Public health professional perspectives on vaccine promotion and strategies for control.

BACKGROUND: A hepatitis E (HepE) vaccine was developed and released in China in 2011. Uptake is currently very limited. The aims of this study were to characterize what public health professionals thought about promoting the HepE vaccine in Shanghai, China, and to develop realistic goals for the HepE vaccine based on this information. METHODS: Public health professionals from Shanghai and other jurisdictions of China were contacted to participate in in-depth qualitative interviews between October 2017 and August 2018. Participants were asked about their perception of the HepE vaccine roll-out. Codes were initially based on the structure of the questionnaire. Subsequently, similar ideas were further developed into themes based on what was present in the transcript data. RESULTS: Thirty-five individuals participated. Major topics of discussion included (1) clarifying the roles and responsibilities of private and public institutions in promoting and marketing the HepE vaccine, (2) identifying what methods of promotion were most efficient, and, (3) endeavoring to formulate a reasonable and realistic goal, if any, for HepE prevention and control in China. Participants emphasized that public sector sources can be trusted sources of information (although the private vaccination company can also be useful in disseminating information) and social media such as WeChat can be good ways to disseminate articles (although netizens may be worried about the spread of fake news). Vaccine promotion is restrained given limited levels of knowledge in the government, hospitals, and public health vaccination centers. CONCLUSION: Successful promotion and use of this vaccine in China, even in limited settings (for instance, certain workplaces, or certain groups) could provide additional information on long-term safety and could promote its adoption in other regions of the world where HepE has high morbidity among pregnant women and other populations.

Vaccination timeliness among newborns and infants in Ethiopia.

BACKGROUND: We characterize the risk factors for delayed polio dose 1, diphtheria-tetanus-pertussis (DTP) dose 1, pentavalent dose 1, and measles dose 1 in Ethiopian infants. We also examine the interaction between institutional delivery and demographic factors on the birth doses of the BCG and polio vaccines to better understand factors influencing vaccination. METHODS: Using the 2011 Ethiopia Demographic and Health Survey, we calculated the distribution of the study population across different demographic and vaccination characteristics. We computed acceleration factors using a multivariable accelerated failure time model with a Weibull distribution to account for left and right censoring. For the birth doses, we further specified an interaction term between institutional delivery and every other a priori specified independent variable to test whether institutional delivery modifies sociodemographic disparities in vaccination timeliness. RESULTS: Low wealth status, home delivery, and ethnicity are risk factors for delayed vaccination of polio 1, DPT 1, pentavalent 1, and measles 1. Religion is a risk factor for measles 1 vaccination delay and rural residence are risk factors for delayed DPT1 and polio 1 doses. For birth doses of polio and BCG, institutional delivery attenuated many sociodemographic disparities in vaccination delay, except for urbanicity, which showed rural dwellers with more delay than urban dwellers with an institutional vs home birth. CONCLUSIONS: Less delayed vaccination among children with institutional deliveries highlights the importance of perinatal care and the potential for promoting healthy behaviors to parents. Persistent disparities between urban and rural residents, even among those with institutional births, can be targeted for future interventions. Timely vaccination is key to prevention of unnecessary childhood mortality.

Childhood vaccination in Kenya: socioeconomic determinants and disparities among the Somali ethnic community.

OBJECTIVES: Kenya has a significant refugee population, including large numbers of Somali migrants. This study examines the vaccination status of Kenyan children and sociodemographic predictors of vaccination, including Somali ethnicity. METHODS: Using the 2014 Kenyan Demographic and Health Survey, we calculated the proportion of non-vaccinated, under-vaccinated, and fully vaccinated children, defining full vaccination as one dose Bacille Calmette-Guerin, three doses polio, three doses pentavalent, and one dose measles. We assessed associations among various factors and vaccination status using multinomial logistic regression and explored the effect of Somali ethnicity through interaction analysis. RESULTS: The study sample comprised 4052 children aged 12-23 months, with 79.4% fully, 19.0% under-, and 1.6% non-vaccinated. Among Somalis, 61.9% were fully, 28.7% under-, and 9.4% non-vaccinated. Somalis had significantly greater odds of under- and non-vaccination than the Kikuyu ethnic group. Wealth and birth setting were associated with immunization status for Somalis and non-Somalis. CONCLUSIONS: Disparities persist in pediatric vaccinations in Kenya, with Somali children more likely than non-Somalis to be under-vaccinated. Health inequalities among migrants and ethnic communities in Kenya should be addressed.

Evaluation of health education interventions on Chinese factory workers' knowledge, practices, and behaviors related to infectious disease.

BACKGROUND: Workplaces are a common location for infectious disease transmission among adults. To provide recommendations regarding appropriate health promotion programs, we evaluated the impact of three different interventions on factory workers. METHODS: In a prospective intervention study carried out from October 2012 to June 2013, three factories were selected and each was assigned a different intervention method (i.e. self-study group, manager training group and interactional group discussion group). Participants were scored on their knowledge, behavior, and hygienic practices related to infectious disease prevention both before and after the intervention. RESULTS: A total of 1154 participants completed the survey before the intervention and 1111 completed the survey after. The sum infectious disease knowledge score in the manager training group was higher after the intervention (9.09/12) than before (8.63/12, t=4.47, p<0.05). There was no significant difference in sum infectious disease knowledge score pre and post intervention for both the self-study group and the interactional group discussion. CONCLUSIONS: Overall, change in health behaviors and hygiene practices were not as affected compared to changes in knowledge after interventions related to infectious disease health promotion. Training managers who then interact with workers may be an effective and efficient way of educating workers on health issues.

Childhood full and under-vaccination in Nigeria, 2013.

BACKGROUND: Nigeria's government is challenged with vaccinating the world's third largest birth cohort within a culturally and socioeconomically diverse country. This study estimated full childhood immunization coverage in Nigeria and characterizes the association between vaccination status and urbanicity, region of residence, ethnicity, and other factors. METHODS: In 2013, households throughout Nigeria were enrolled in the Demographic and Health Survey which included questions about vaccination. We defined full vaccination of a child as having received a single dose of bacillus Calmete-Guerin (BCG), one dose of measles-containing vaccine (MCV), three doses of diphtheria, pertussis, tetanus (DPT), and four doses of oral polio vaccine (OPV). Using a multinomial logistic regression model, full vaccination and under-vaccination versus non-vaccination was regressed onto various demographic and socioeconomic characteristics. RESULTS: Among 5759 children 1 year of age, 25.5% were fully vaccinated, 47.9% were under-vaccinated, and 26.6% had not received any vaccinations. Children were more likely to be fully vaccinated if they belonged to wealthier families, resided in southern regions of the country, were Christian, belonged to the Igbo or Yoruba ethnic group, had mothers who made ≥5 antenatal care visits, delivered at an institution, or were more highly educated. CONCLUSIONS: Full vaccination among children in Nigeria is exceptionally low by global standards and certain groups, such as Muslims and individuals in northern regions who are higher risk of non- or under-vaccination should be targeted by vaccination programs. Providing a wide range of health care services for mothers and pregnant women could improve full vaccination of children.

Vaccination status of children aged 1-4 years in Afghanistan and associated factors, 2015.

BACKGROUND: Childhood mortality in Afghanistan fell by half between 1990 and 2015, due in part to the government's commitment to improving pediatric immunization services. Although progress has been made, immunization coverage has nonetheless remained low with only 65% of children receiving the third dose of Diphtheria-Pertussis-Tetanus (DPT3) based on WHO estimates. This study aims to calculate the proportion of Afghan children aged 1-4 years who were fully vaccinated, under-vaccinated, or non-vaccinated with government-recommended Expanded Program on Immunization vaccines and identify predictors related to the family's sociodemographic status and maternal autonomy. METHODS: Data from the 2015 Afghanistan Demographic and Health Survey was used to calculate the proportion of children who were fully vaccinated (i.e. received all recommended vaccines), under-vaccinated (i.e. received some, but not all), and non-vaccinated (i.e. did not receive any vaccines) according to WHO guidelines. A multivariable multinomial logistic regression model generated odds ratios for under-vaccination and non-vaccination versus full vaccination, and examined associations between independent factors and full vaccination status. RESULTS: We found 40.6% of Afghan children age 1-4 were fully vaccinated, 42.4% under-vaccinated, and 17% non-vaccinated. Large disparities characterized immunization coverage among provinces and between urban and rural regions. Birthing in a government institution (vs. non-institutional setting), a higher number of antenatal care visits, and a visit to a health facility in the past 12 months were all associated with increased odds of full immunization. Factors related to maternal autonomy including maternal decision-making and maternal attitudes towards beating were also significantly associated with vaccination status. CONCLUSION: Approximately 60% of children in Afghanistan are under-vaccinated or non-vaccinated, leaving millions of children unnecessarily at risk for vaccine-preventable diseases. Engagement with community and religious leaders to create programs that increase women's autonomy and expand access to institutional delivery could lead to downstream increases in childhood vaccination coverage.

Causality assessment of serious and severe adverse events following immunization in India: a 4-year practical experience.

BACKGROUND: India has implemented the World Health Organization's revised Causality Assessment Protocol for adverse events following immunization (AEFI). We describe the number and types of serious/severe AEFIs, including deaths. RESEARCH DESIGN AND METHODS: Analysis of causality classification of reported serious/severe AEFIs from 1 January 2012 to 7 January 2016 was done. Classification includes (A) consistent with causal association to immunization; (B) indeterminate; (C) coincidental association; or (D) unclassifiable. We present descriptive statistics across each category. RESULTS: Analysis of causality assessment completed for 1037 reports of serious AEFIs: 499 (48%) were causally associated, 84 (8%) were indeterminate, 323 (31%) were coincidental, and 131 (13%) were unclassifiable. Of the 499 reports in the A category, the events were causally linked to vaccine product for 189 (18%), to immunization error for 135 (13%), and to immunization anxiety for 175 (17%). Among 279 reported deaths, more than half (55%; n = 153) were coincidental events and 37% were unclassifiable. CONCLUSIONS: Causality assessment of AEFI cases is an important component of vaccination programs and post-marketing surveillance of vaccines. Field reporting and investigation of AEFIs can be improved for many severe or serious reports, most of which are not causally linked to the vaccination program.