Individual-, family- and community-level determinants of full vaccination coverage among children aged 12–23 months in western Kenya

To identify individual-, family-, and community-level determinants of full vaccination status at most challenging areas in Kenya, we conducted a cross-sectional study among children aged 12–23 months and their mothers. 1965 children were involved in this research and their mothers completed a questionnaire. Middle or high knowledge of vaccination schedule (Adjusted Odds Ratio (AOR) = 2.69, 95%CI: 2.01–3.60 or AOR = 8.12, 95%CI:5.50–11.97), medium/long birth interval or first birth (AOR = 2.46, 95%CI: 1.29–4.69 or AOR = 1.84, 95%CI:1.10–3.09 or AOR = 2.14, 95%CI: 1.20–3.84), less than 5 children under five years old (AOR = 1.39, 95%CI: 1.04–1.88) and highest community health worker's (CHWs) performance (AOR = 2.20, 95%CI: 1.39–3.47) were significantly associated with complete vaccination status in the final multiple regression model. In addition, a interaction between literacy and wealth was significantly related in full vaccination status (AOR = 1.38, 95%CI: 1.08–1.75). Increased frequency and quality of CHW visits could be effective intervention to enhance vaccination coverage. Future interventions focusing on vaccination coverage should be given more attention especially to high risk group identified in this study.     

Home-based record prevalence among children aged 12–23 months from 180 demographic and health surveys

BackgroundThere is currently a re-focus at the global level on the importance of the home-based record within vaccination service delivery as an important information resource but there are few reports of ever and current home-based record prevalence across countries.MethodsWe considered all Demographic and Health Surveys (starting with DHS round 3) conducted between 1993 and 2013 for which a final dataset was available in the public domain at the time of the analysis. Ever and current prevalence of home-based records for recording vaccination was estimated for children aged 12–23 months at the time of the survey through a secondary analysis of data from 180 Demographic and Health Surveys conducted in 67 countries derived from questions asked of women aged 15–49 years for their children on home-based record availability and retention. Ever home-based record prevalence is the proportion of children aged 12–23 months who have ever received a home-based record. Current home-based record prevalence is the proportion of children aged 12–23 months for whom a home-based record was available for viewing by the surveyor at the time of the survey.ResultsEstimated ever home-based record prevalence was ≥90% in 116 surveys from 52 countries and was <70% in 15 surveys from 7 countries. Estimated current home-based record prevalence was ≥80% in 31 surveys from 23 countries and was <50% in 51 surveys from 24 countries. Current home-based record prevalence was <80% as of the most recent survey during 2010–2013 for five (Bangladesh, Ethiopia, Nigeria, Indonesia and Pakistan) of the ten countries with the largest birth cohorts globally. Among 34 countries that conducted three or more DHS, we observed improvements in both ever and current home-based record prevalence of >10% points in six countries. Current home-based record prevalence increased >10% points in six countries where the ever prevalence was maintained at ≥90% across the period of observation. And, no meaningful change was observed in estimated ever and current home-based record prevalence in 11 countries, five of which maintained ever prevalence ≥90% across the period of observation. High home-based record loss rates were observed in many countries.ConclusionsThe results here show that despite improvements in the availability, utilization and retention of home-based records for recording vaccination history in some countries, opportunities remain to change the mind-set in many national immunization programmes around the importance of the home-based record, particularly in countries with large birth cohorts. Immunization programmes are encouraged to monitor ever and current home-based record prevalence. Nationally representative household surveys collecting information on immunization coverage should include ever and current home-based record prevalence in the standard survey reports and tables to better enable programme managers to identify problems and target corrective action.     

Prevalence of adiposity and its association with sleep duration,quality, and timing among 9–12-year-old children in Guangzhou,China

Background

Short sleep duration has been reported to be associated with obesity in children, but findings are not consistent. Since few studies have examined the relationship between more complex sleep characteristics and obesity, we examined the association between adiposity and self-reported sleep duration, bedtime, and sleep quality in 9–12-year-old Chinese children using multilevel mixed models.

Factors associated with complete immunization coverage in children aged 12¿23 months in Ambo Woreda, Central Ethiopia

ABSTRACT: BACKGROUND: Vaccination is a proven tool in preventing and eradicating communicable diseases, but a considerable proportion of childhood morbidity and mortality in Ethiopia is due to vaccine preventable diseases. Immunization coverage in many parts of the country remains low despite the efforts to improve the services. In 2005, only 20% of the children were fully vaccinated and about 1 million children were unvaccinated in 2007. The objective of this study was to assess complete immunization coverage and its associated factors among children aged 12-23 months in Ambo woreda. METHODS: A cross-sectional community-based study was conducted in 8 rural and 2 urban kebeles during January- February, 2011. A modified WHO EPI cluster sampling method was used for sample selection. Data on 536 children aged 12-23 months from 536 representative households were collected using trained nurses. The data collectors assessed the vaccination status of the children based on vaccination cards or mother's verbal reports using a pre-tested structured questionnaire through house-to-house visits. Bivariate and multivariate logistic regression analyses were used to assess factors associated with immunization coverage. RESULTS: About 96% of the mothers heard about vaccination and vaccine preventable diseases and 79.5% knew the benefit of immunization. About 36% of children aged 12-23 months were fully vaccinated by card plus recall, but only 27.7% were fully vaccinated by card alone and 23.7% children were unvaccinated. Using multivariate logistic regression models, factors significantly associated with complete immunization were antenatal care follow-up (adjusted odds ratio(AOR=2.4, 95% CI: 1.2- 4.9), being born in the health facility (AOR=2.1, 95% CI: 1.3-3.4), mothers' knowledge about the age at which vaccination begins (AOR= 2.9, 95% CI: 1.9-4.6) and knowledge about the age at which vaccination completes (AOR=4.3, 95% CI: 2.3-8), whereas area of residence and mother's socio-demographic characteristics were not significantly associated with full immunization among children. CONCLUSION: Complete immunization coverage among children aged 12-23 months remains low. Maternal health care utilization and knowledge of mothers about the age at which child begins and finishes vaccination are the main factors associated with complete immunization coverage. It is necessary that, local interventions should be strengthened to raising awareness of the community on the importance of immunization, antenatal care and institutional delivery.     

Incidence and aetiology of bacterial meningitis among children aged 1–59 months in South Asia: systematic review and meta-analysis

BackgroundBacterial meningitis is a significant cause of morbidity and mortality worldwide among children aged 1–59 months. We aimed to describe its burden in South Asia, focusing on vaccine-preventable aetiologies.MethodsWe searched five databases for studies published from January 1, 1990, to April 25, 2017. We estimated incidence and aetiology-specific proportions using random-effects meta-analysis. In secondary analyses, we described vaccine impact and pneumococcal meningitis serotypes.ResultsWe included 48 articles cumulatively reporting 20,707 cases from 1987 to 2013. Mean annual incidence was 105 (95% confidence interval [CI], 53–173) cases per 100,000 children. On average, Haemophilus influenzae type b (Hib) accounted for 13% (95% CI, 8–19%) of cases, pneumococcus for 10% (95% CI, 6–15%), and meningococcus for 1% (95% CI, 0–2%). These meta-analyses had substantial between-study heterogeneity (I² > 78%, P < 0.0001). Among studies reporting only confirmed cases, these three bacteria caused a median of 78% cases (IQR, 50–87%). Hib meningitis incidence declined by 72–83% at sentinel hospitals in Pakistan and Bangladesh, respectively, within two years of implementing nationwide vaccination. On average, PCV10 covered 49% (95% CI, 39–58%), PCV13 covered 51% (95% CI, 40–61%), and PPSV23 covered 74% (95% CI, 67–80%) of pneumococcal meningitis serotypes. Lower PCV10 and PCV13 serotype coverage in Bangladesh was associated with higher prevalence of serotype 2, compared to India and Pakistan.ConclusionsSouth Asia has relatively high incidence of bacterial meningitis among children aged 1–59 months, with vaccine-preventable bacteria causing a substantial proportion. These estimates are likely underestimates due to multiple epidemiological and microbiological factors. Further research on vaccine impact and distribution of pneumococcal serotypes will inform vaccine policymaking and implementation.     

Trends in compliance with two-dose influenza vaccine recommendations in children aged 6 months through 8 years, 2010–2015

BackgroundChildren aged 6 months through 8 years may require two doses of influenza vaccine for adequate immune response against the disease. However, poor two-dose compliance has been reported in the literature.MethodsWe analyzed data for >2.6 million children from six immunization information system (IIS) sentinel sites, and assessed full vaccination coverage and two-dose compliance in the 2010–2015 influenza vaccination seasons. Full vaccination was defined as having received at least the recommended number of influenza vaccine doses (one or two), based on recommendations from the Advisory Committee on Immunization Practices. Two-dose compliance was defined as the percentage of children during each season who received at least two doses of influenza vaccine among those who required two doses and initiated the series.ResultsAcross seasons, ⩾1-dose influenza vaccination coverage was mainly unchanged among 6–23 month olds (range: 60.9–66.6%), 2–4 year olds (range: 44.8–47.4%), and 5–8 year olds (range: 34.5–38.9%). However, full vaccination coverage showed increasing trends from 2010–11 season to 2014–15 season (6–23 months: 43.0–46.5%; 2–4 year olds: 26.3–39.7%; 5–8 year olds, 18.5–33.9%). Across seasons, two-dose compliance remained modest in children 6–23 months (range: 63.3–67.6%) and very low in older children (range: 11.6–18.7% in children 2–4 years and 6.8–13.3% in children 5–8 years). In the 2014–15 season, among children who required and received 2 doses, only half completed the two-dose series before influenza activity peaked.ConclusionsImproved messaging of the two-dose influenza vaccine recommendations is needed for providers and parents. Providers are encouraged to determine a child’s eligibility for two doses of influenza vaccine using the child’s vaccination history, and to vaccinate children early in the season so that two-dose series are completed before influenza peaks.     

Efficacy and safety of a quadrivalent influenza vaccine in children aged 6–35 months: A global,multiseasonal, controlled,randomized Phase III study

BackgroundChildren are an important target group for influenza vaccination, but few studies have prospectively evaluated influenza vaccine efficacy (VE) in children under 3 years of age. This was a randomized Phase III trial to assess the efficacy, immunogenicity, and safety of an inactivated quadrivalent influenza vaccine (QIV) in young children (EudraCT: 2016–004904–74).MethodsInfluenza-naïve children aged 6–35 months were randomized during three influenza seasons to receive vaccination with QIV or a non-influenza control vaccine. One group of participants was revaccinated with QIV in the subsequent influenza season. The primary efficacy endpoint was the absolute VE of QIV against influenza caused by any circulating strain. Key secondary efficacy endpoints included the absolute VE of QIV against influenza due to antigenically matching strains and immunogenicity. Safety and reactogenicity were also evaluated.ResultsIn total, 1005 children received QIV and 995 received control vaccine. Influenza A/B infection due to any circulating influenza strain occurred less frequently in children who received QIV versus children receiving a control vaccine. The absolute VE of QIV against any circulating influenza strain was 54% (95% confidence interval [CI]: 37%, 66%). The absolute VE of QIV against antigenically matching influenza strains was 68% (95% CI: 45%, 81%). Mean hemagglutination inhibition titers for all influenza strains in the QIV group increased post-vaccination, whereas increases were minimal in the control vaccine group; results from virus neutralization and neuraminidase-inhibition assays were generally consistent with the hemagglutination inhibition assay findings. Approximately 12 months after primary vaccination with QIV, antibody titers remained higher than pre-vaccination titers for most strains. In participants who were revaccinated, QIV elicited strong antibody responses. The overall safety profile and reactogenicity of QIV was comparable with control vaccine.ConclusionPrimary vaccination with QIV was well tolerated and effective in protecting children aged 6–35 months against influenza.     

Self-perception of weight status and its association with weight-related knowledge,attitudes, and behaviors among Chinese children in Guangzhou

Background

How weight perception influences weight-related knowledge, attitudes, and behaviors in Chinese children is unknown. We investigated self-perception of body weight and its correlates, and analyzed the relationship between weight perception and weight-related knowledge, attitudes, and behaviors in children in Guangzhou, China.

Prevalence and factors associated with vitamin A deficiency in preschool children from Teresina, Piauí, Brazil

Vitamin A deficiency is a public health problem in the Northeast of Brazil. This study aimed to determine the prevalence of vitamin A deficiency and associated factors among preschool children in Teresina, Piauí, Brazil. We studied the serum retinol levels and socioeconomic and demographic characteristics of 631 children from 36 to 83 months of age. The statistical association between each of the above characteristics and serum retinol levels was investigated by univariate and multivariate linear regression analysis. Mean serum retinol was 1.21 mmol/L (95%CI: 1.17-1.25 micromol/L) and was independent of gender (p = 0.259). Prevalence of vitamin A deficiency (retinol < 0.69 micromol/L) was 15.4% (95%CI: 12.7-18.4), with a tendency to decrease with age. Acceptable but not adequate retinol levels (0.70 to 1.04 micromol/L) were observed in 29% of children (95%CI: 25.2-32.4). There were positive associations between retinol levels and age, income, vitamin A supplementation, and maternal schooling. Vitamin A deficiency appeared as a moderately serious public health problem, emphasizing the importance of strategies to combat this problem in the region.     

Estimated influenza illnesses and hospitalizations averted by influenza vaccination among children aged 6–59 months in Suzhou,China, 2011/12 to 2015/16 influenza seasons

BackgroundThere are few estimates of vaccination-averted influenza-associated illnesses in China.MethodsWe used a mathematical model and Monte Carlo algorithm to estimate numbers and 95% confidence intervals (CI) of influenza-associated outcomes (hospitalization, illness, and medically-attended (MA) illness) averted by vaccination among children aged 6–59 months in Suzhou from October 2011–September 2016. Influenza illnesses included non-hospitalized MA influenza illnesses and non-MA influenza illnesses. The numbers of influenza-associated outcomes averted by vaccination were the difference between the expected burden if there were no vaccination given and the observed burden with vaccination. The model incorporated the disease burden estimated based on surveillance data from Suzhou University Affiliated Children’s Hospital (SCH) and data from health utilization surveys conducted in the catchment area of SCH, age-specific estimates of influenza vaccination coverage in Suzhou from the Expanded Program on Immunization database, and influenza vaccine effectiveness estimates from previous publications. Averted influenza estimations were presented as absolute numbers and in terms of the prevented fraction (PF). A hypothetical scenario with 50% coverage (but identical vaccine effectiveness) over the study period was also modeled.ResultsIn ~250,000 children, influenza vaccination prevented an estimated 731 (CI: 549–960) influenza hospitalizations (PF: 6.2% of expected, CI: 5.8–6.6%) and 10,024 (7593–12,937) influenza illnesses (PF: 6.5%, 6.4–6.7%), of which 8342 (6338–10,768) were MA (PF: 6.6%, 6.4–6.7%) from 2011 to 2016. The PFs declined each year along with decreasing influenza vaccination coverage. If 50% of the study population had been vaccinated over time, the estimated numbers of averted cases during the study period would have been 4059 (3120–5762) influenza hospitalizations (PF: 27.2%, 26.4–27.9%) and 56,215 (42,925–78,849) influenza illnesses (PF: 28.5%, 28.3–28.7%), of which 46,596 (35,662–65,234) would be MA (PF: 28.5%, 28.3–28.7%).ConclusionInfluenza vaccination is estimated to have averted influenza-associated illness outcomes even with low coverage in children aged 6–59 months in Suzhou. Increasing influenza vaccination coverage in this population could further reduce illnesses and hospitalizations.     

Seasonal influenza vaccine effectiveness against medically attended influenza illness among children aged 6–59 months,October 2011–September 2012: A matched test-negative case–control study in Suzhou,China

BackgroundSeasonal influenza infections among young children in China lead to substantial numbers of hospitalizations and financial burden. This study assessed the seasonal influenza vaccine effectiveness (VE) against laboratory confirmed medically attended influenza illness among children in Suzhou, China, from October 2011–September 2012.MethodsWe conducted a test-negative case–control study among children aged 6–59 months who sought care at Soochow University Affiliated Children's Hospital (SCH) from October 2011–September 2012. A case was defined as a child with influenza-like illness (ILI) or severe acute respiratory infection (SARI) with an influenza-positive nasopharyngeal swab by rRT-PCR. Controls were selected from children presenting with ILI or SARI without laboratory confirmed influenza. We conducted 1:1 matching by age and admission date. Vaccination status was verified from the citywide immunization system database. VE was calculated with conditional logistic regression: (1 − OR) × 100%.ResultDuring the study period, 2634 children aged 6–59 months presented to SCH with ILI (1975) or SARI (659) and were tested for influenza. The vaccination records were available for 69% (1829; ILI: 1354, SARI: 475). Among those, 23% (427) tested positive for influenza, and were included as cases. Among influenza positive cases, the vaccination rates were 3.2% for SARI and 4.5% for ILI. Among controls, the vaccination rates were 13% for SARI, and 11% for ILI. The overall VE against lab-confirmed medically attended influenza virus infection was 67% (95% CI: 41–82). The VE for SARI was 75% (95% CI: 11–93) and for ILI was 64% (95% CI: 31–82).ConclusionsThe seasonal influenza vaccine was effective against medically attended lab-confirmed influenza infection in children aged 6–59 months in Suzhou, China in the 2011–12 influenza season. Increasing seasonal influenza vaccination among young children in Suzhou may decrease medically attended influenza-associated ILI and SARI cases in this population.     

Characterization of GII.4 noroviruses circulating among children with acute gastroenteritis in Pune,India: 2005–2013

Genogroup II genotype 4 noroviruses (GII.4 NoVs), an important cause of sporadic childhood gastroenteritis worldwide, undergo continuous evolution leading to the periodic emergence of novel variants. The present study was undertaken for surveillance of GII.4 NoVs and identification and characterization of GII.4 variants circulating among children with sporadic gastroenteritis in Pune, India during 2005–2013. Among the 12 GII genotypes detected in the study, GII.4 was predominant. Sequencing and phylogenetic analysis of ORF2 (major capsid protein VP1 gene) of the GII.4 NoVs revealed circulation of seven GII.4 variants, Hunter_2004 (2005–2007), Yerseke_2006a (2006), DenHaag_2006b (2007), Osaka_2007 (2007–2009), Apeldoorn_2007 (2008), New Orleans_2009 (2008–2012) and Sydney_2012 (2013), with the Pune strains grouping with the contemporary global reference strains. The Hunter_2004, Osaka_2007 and New Orleans_2009 variants showed prolonged circulation, with the Hunter_2004 and New Orleans_2009 variants differentiating into temporally separated sub-clusters. Analysis of VP1 sequences and predicted structures of the GII.4 variants identified variant specific amino acid positions, particularly in and near (within 8A^°) the epitopes A-E, displaying differences in the sequence and physicochemical characteristics of the different variants. Comparison with the reference strains of each of the GII.4 variants revealed up to 11 amino acid substitutions at the variant specific positions in the GII.4 strains from Pune. Amino acid variations were also noted among the strains of the same GII.4 variant in Pune. The strains of different sub-clusters identified in the Hunter_2004 and New Orleans_2009 variants showed differences in sequence and physicochemical properties of either or all of the epitopes A, C and E. The study thus describes the temporal variations and diversity of the GII.4 strains in Pune and emphasizes continuous monitoring and analysis of the GII.4 variants.     

Trends and spatial distribution of deaths of children aged 12-60 months in São Paulo,Brazil, 1980-98

OBJECTIVE: To describe trends in the mortality of children aged 12-60 months and to perform spatial data analysis of its distribution at the inner city district level in São Paulo from 1980 to 1998. METHODS: Official mortality data were analysed in relation to the underlying causes of death. The population of children aged 12-60 months, disaggregated by sex and age, was estimated for each year. Educational levels, income, employment status, and other socioeconomic indices were also assessed. Statistical Package for Social Sciences software was used for the statistical processing of time series. The Cochrane-Orcutt procedure of generalized least squares regression analysis was used to estimate the regression parameters with control of first-order autocorrelation. Spatial data analysis employed the discrimination of death rates and socioeconomic indices at the inner city district level. For classifying area-level death rates the method of K-means cluster analysis was used. Spatial correlation between variables was analysed by the simultaneous autoregressive regression method. FINDINGS: There was a steady decline in death rates during the 1980s at an average rate of 3.08% per year, followed by a levelling off. Infectious diseases remained the major cause of mortality, accounting for 43.1% of deaths during the last three years of the study. Injuries accounted for 16.5% of deaths. Mortality rates at the area level clearly demonstrated inequity in the city''s health profile: there was an increasing difference between the rich and the underprivileged social strata in this respect. CONCLUSION: The overall mortality rate among children aged 12-60 months dropped by almost 30% during the study period. Most of the decline happened during the 1980s. Many people still live in a state of deprivation in underserved areas. Time-series and spatial data analysis provided indications of potential value in the planning of social policies promoting well-being, through the identification of factors affecting child survival and the regions with the worst health profiles, to which programmes and resources should be preferentially directed.     

Prevalence and factors associated with incomplete immunization of children (12–23 months) in Kwabre East District,Ashanti Region,Ghana

Background

Childhood immunization is one of the most cost effective health interventions but its rate has been declining recently in Ghana. Information on immunization coverage and determinants is needed to improve immunization programmes. The objective of this study was to determine the prevalence and factors associated with incomplete immunization of children (12–23 months) in Kwabre East District, Ghana.

Methods

A cross-sectional, community-based survey involving 322 children and their mothers was carried out. Data were collected on socio-demographic characteristics of mothers, childhood immunization history and mothers’ knowledge and practices of immunization using a structured questionnaire. Children were classified as incompletely immunized if they failed to receive at least one of 8 vaccine doses: - one dose of Bacillus Calmette–Guérin (BCG), 3 doses each of pentavalent, 3 doses of polio and one dose of measles per WHO/UNICEF definition. Chi-square and logistic regression analyses were used to identify the factors associated with incomplete immunisation.

Results

The prevalence of incomplete immunization was low (15.5%) suggesting high immunisation coverage but the coverage of the second measles dose, taken at 18 months of age, was the lowest (23.9%). Most of the mothers knew the importance of immunisation (95.7%) and at least one vaccine-preventable disease or symptom (84.9%). Two factors associated with incomplete immunisation in bivariate analyses (community of residence, and mother’s knowledge of number of oral polio vaccines given to children) were no longer significant in a logistic regression model. Compared to children in Aboaso, children in Gyamfi Wonoo (AOR?=?1.81, 95% CI?=?0.80–4.08), Mamponteng (Bonwunu) (AOR?=?0.59, 95% CI?=?0.24–1.48) and Mamponteng (Town) (AOR?=?0.63, 95% CI?=?0.26–1.55) had similar odds of incomplete immunisation. Similarly, mother’s lack of knowledge of the number of doses of polio vaccine given to children had no effect on the odds of incomplete immunisation (AOR?=?0.53, 95% CI?=?0.22–1.26).

Conclusions

Immunization coverage is high in the Kwabre East district but very few children received the second measles dose. None of the maternal and child factors assessed is associated with immunisation coverage. Further research is needed to identify the determinants of immunisation coverage and the reasons for the low uptake of second measles dose in the study area.

     

Risk factors for measles in children aged 8 months–14 years in China after nationwide measles campaign: A multi-site case-control study, 2012–2013

IntroductionEndemic measles persists in China, despite >95% reported coverage of two measles-containing vaccine doses and nationwide campaign that vaccinated more than 100 million children in 2010. In 2011, almost half of the 9943 measles cases in China occurred in children eligible for measles vaccination. We conducted a case-control study during 2012–2013 to identify risk factors for measles infection in children aged 8 months–14 years.MethodsChildren with laboratory-confirmed measles were age- and neighborhood-matched with three controls. We interviewed parents of case and control infants on potential risk factors for measles. We calculated adjusted matched odds ratios and 95% confidence intervals of risk factors. We calculated attributable fractions for risk factors that could be interpreted as causal and vaccine efficacy (VE) for the measles containing vaccine (MCV) used in the Chinese immunization program.ResultsIn all, 969 case-patients and 2845 controls were enrolled. In multivariable analysis, lack of measles vaccination both overall (mOR 22.7 [16.6, 31.1] and when stratified by region (east region, mOR 74.2 [27.3, 202]; central/western regions mOR 17.4 [12.5, 24.3]), hospital exposure (mOR 63.0, 95% CI [32.8, 121]), and migration among counties (overall mOR 3.0 [2.3, 3.9]) were significant risk factors. The calculated VE was 91.9–96.1% for a single dose of MCV and 96.6–99.5% for 2 doses.ConclusionsLack of vaccination was the leading risk factor for measles infection, especially in children born since the 2010 supplementary immunization activity. Reducing missed vaccination opportunities, improving immunization access for migrant children, and strengthening school/kindergarten vaccine checks are needed to strengthen the routine immunization program and maintain progress toward measles elimination in China.     

The double burden of overweight or obesity and anemia among women married as children in India: A case of the Simpson’s paradox

BackgroundChild marriage, defined as marriage before age 18 years, could impact women’s nutritional status through biological as well as environmental and socioeconomic attributes affecting diet and lifestyle behaviors. This study aims to examine whether women married as children have a differential risk of individual level double burden of overweight/obesity and anemia at adult age compared to women married as adults.MethodsUsing nationally representative data from India we estimated multinomial logistic regressions to obtain relative risk ratios (RRR) in favor of mutually exclusive anemia and overweight/ obesity conditions among women aged 20–49 years. We estimated the model for full sample and for sub-samples by household wealth groups.ResultsWe find that women who were married as children had a lower relative risk (RRR=0.941) of the double burden of anemia and overweight/obesity in the full sample. However, when sociodemographic correlates were accounted for and assessed in sub-groups by wealth groups, they had a higher relative risk (ARRR ranging from 1.079 to 1.204) of the double burden compared to women married as adults.ConclusionOur results thus portray a classic case of the Simpson’s paradox by documenting a reversal of association between child marriage and occurrence of the double burden of malnutrition in the subgroup level than that in the general population. This finding provides a critical policy insight for effective public health interventions to improve women’s health and wellbeing, particularly in low resource settings.     

A randomized clinical trial assessing immunogenicity and safety of a double dose of virosomal-adjuvanted influenza vaccine administered to unprimed children aged 6–35 months

This study evaluated the immunogenicity of a double dose of the seasonal virosomal-adjuvanted influenza vaccine (Inflexal V, Crucell, The Netherlands) in 65 previously unvaccinated children aged less than 3 years: 43 received double doses (two doses of 0.50 mL 4 weeks apart) and 22 standard doses (two doses of 0.25 mL 4 weeks apart). Both treatments evoked a response that satisfied the EMEA criteria for adequate immunogenicity for all three vaccine strains, but the double dose had a significantly greater effect on all of the studied parameters of humoral and cell-mediated immune response (p < 0.05). This result was achieved without any increase in the incidence of local and systemic adverse events. This means that doubling the dose of the virosomal-adjuvanted influenza vaccine (i.e. administering the same dose as that usually given to older children) effectively and safely increases the immune response to inactivated influenza vaccine in unprimed children aged less than 3 years.