Modeling and presentation of vaccination coverage estimates using data from household surveys

It is becoming increasingly popular to produce high-resolution maps of vaccination coverage by fitting Bayesian geostatistical models to data from household surveys. Usually, the surveys adopt a stratified cluster sampling design. We discuss a number of crucial choices with respect to two key aspects of the map production process: the acknowledgement of the survey design in modeling, and the appropriate presentation of estimates and their uncertainties. Specifically, we consider the importance of accounting for urban/rural stratification and cluster-level non-spatial excess variation in survey outcomes, when fitting geostatistical models. We also discuss the trade-off between the geographical scale and precision of model-based estimates, and demonstrate visualization methods for mapping and ranking that emphasize the probabilistic interpretation of results. A novel approach to coverage map presentation is proposed to allow comparison and control of the overall map uncertainty. We use measles vaccination coverage in Nigeria as a motivating example and illustrate the different issues using data from the 2018 Nigeria Demographic and Health Survey.     

Issues and considerations in the use of serologic biomarkers for classifying vaccination history in household surveys

Accurate estimates of vaccination coverage are crucial for assessing routine immunization program performance. Community based household surveys are frequently used to assess coverage within a country. In household surveys to assess routine immunization coverage, a child's vaccination history is classified on the basis of observation of the immunization card, parental recall of receipt of vaccination, or both; each of these methods has been shown to commonly be inaccurate. The use of serologic data as a biomarker of vaccination history is a potential additional approach to improve accuracy in classifying vaccination history. However, potential challenges, including the accuracy of serologic methods in classifying vaccination history, varying vaccine types and dosing schedules, and logistical and financial implications must be considered. We provide historic and scientific context for the potential use of serologic data to assess vaccination history and discuss in detail key areas of importance for consideration in the context of using serologic data for classifying vaccination history in household surveys. Further studies are needed to directly evaluate the performance of serologic data compared with use of immunization cards or parental recall for classification of vaccination history in household surveys, as well assess the impact of age at the time of sample collection on serologic titers, the predictive value of serology to identify a fully vaccinated child for multi-dose vaccines, and the cost impact and logistical issues on outcomes associated with different types of biological samples for serologic testing.     

Impact of vaccine stockouts on immunization coverage in Nigeria

Improving immunization coverage requires creating reliable supply of vaccines and immunization supplies; trained and incentivized health workers; and strategies to improve the demand for immunization. Yet, the interplay of demand and supply side factors on immunization coverage has not been evaluated in literature with data. We use data from Nigeria and a mixed-effects general linear model to estimate the effect of vaccine availability on routine immunization coverage and to identify demand and health system factors which affect this relationship. We find that when vaccine stockouts occur at Local Government Area stores in Nigeria, they significantly decrease the number of children immunized, and for most vaccines, the effect lasts for several months after a stockout. Some of the demand lost when a stockout occurs is recovered over the following six months as children catch up with the regimen. The magnitude of the impact varies across different vaccines.     

Monitoring equity in vaccination coverage: A systematic analysis of demographic and health surveys from 45 Gavi-supported countries

Objectives(1) To conduct a systematic analysis of inequalities in childhood vaccination coverage in Gavi-supported countries; (2) to comparatively assess alternative measurement approaches and how they may affect cross-country comparisons of the level of inequalities.MethodsUsing the most recent Demographic and Health Surveys (2005–2014) in 45 Gavi-supported countries, we measured inequalities in vaccination coverage across seven dimensions of social stratification and of vulnerability to poor health outcomes. We quantified inequalities using pairwise comparisons (risk differences and ratios) and whole spectrum measures (slope and relative indices of inequality). To contrast measurement approaches, we pooled the estimates using random-effects meta-analyses, ranked countries by the magnitude of inequality and compared agreement in country ranks.ResultsAt the aggregate level, maternal education, multidimensional poverty, and wealth index poverty were the dimensions associated with the largest inequalities. In 36 out of 45 countries, inequalities were substantial, with a difference in coverage of 10 percentage points or more between the top and bottom of at least one of these social dimensions. Important inequalities by child sex, child malnutrition and urban/rural residence were also found in a smaller set of countries. The magnitude of inequality and ranking of countries differed across dimension and depending on the measure used. Pairwise comparisons could not be estimated in certain countries. The slope and relative indices of inequality were estimated in all countries and produced more stable country rankings, and should thus facilitate more reliable international comparisons.ConclusionsInequalities in vaccination coverage persist in a large majority of Gavi-supported countries. Inequalities should be monitored across multiple dimensions of vulnerability. Using whole spectrum measures to quantify inequality across multiple ordered social groups has important advantages. We illustrate these findings using an equity dashboard designed to support decision-making in the Sustainable Development Goals period.     

Increases in vaccination coverage of healthcare personnel following institutional requirements for influenza vaccination: a national survey of U.S. hospitals

Background

Institutional requirements for influenza vaccination, ranging from policies that mandate declinations to those terminating unvaccinated healthcare personnel (HCP), are increasingly common in the US. Our objective was to determine HCP vaccine uptake following requirements for influenza vaccination at US hospitals.

Methods

Survey mailed in 2011 to a nationally representative sample of 998 acute care hospitals. An institutional requirement was defined as an institutional policy that requires receipt or declination of influenza vaccination, with or without consequences for vaccine refusal. Respondents reported institutional-level, seasonal influenza vaccination coverage, if known, during two consecutive influenza seasons: the season prior to (i.e., pre-requirement), and the first season of requirement (i.e., post-requirement). Weighted univariate and multivariate analyses accounted for sampling design and non-response.

Results

808 (81.0%) hospitals responded. Of hospitals with institutional requirements for influenza vaccination (n = 440), 228 hospitals met analytic inclusion criteria. Overall, mean reported institutional-level influenza vaccination coverage among HCP rose from 62.0% in the pre-requirement season to 76.6% in the post-requirement season, representing a single-season increase of 14.7 (95% CI: 12.6-16.7) percentage points. After adjusting for potential confounders, single-season increases in influenza vaccination uptake remained greater among hospitals that imposed consequences for vaccine refusal, and among hospitals with lower pre-requirement vaccination coverage. Institutional characteristics were not associated with vaccination increases of differential magnitude.

Conclusion

Hospitals that are unable to improve suboptimal influenza vaccination coverage through multi-faceted, voluntary vaccination campaigns may consider institutional requirements for influenza vaccination. Rapid and measurable increases in vaccination coverage followed institutional requirements at hospitals of varying demographic characteristics.     

Human papillomavirus (HPV) vaccination coverage in young Australian women is higher than previously estimated: Independent estimates from a nationally representative mobile phone survey

Background

Accurate estimates of coverage are essential for estimating the population effectiveness of human papillomavirus (HPV) vaccination. Australia has a purpose built National HPV Vaccination Program Register for monitoring coverage, however notification of doses administered to young women in the community during the national catch-up program (2007–2009) was not compulsory. In 2011, we undertook a population-based mobile phone survey of young women to independently estimate HPV vaccination coverage.

Methods

Randomly generated mobile phone numbers were dialed to recruit women aged 22–30 (age eligible for HPV vaccination) to complete a computer assisted telephone interview. Consent was sought to validate self reported HPV vaccination status against the national register. Coverage rates were calculated based on self report and weighted to the age and state of residence structure of the Australian female population. These were compared with coverage estimates from the register using Australian Bureau of Statistics estimated resident populations as the denominator.

Results

Among the 1379 participants, the national estimate for self reported HPV vaccination coverage for doses 1/2/3, respectively, weighted for age and state of residence, was 64/59/53%. This compares with coverage of 55/45/32% and 49/40/28% based on register records, using 2007 and 2011 population data as the denominators respectively. Some significant differences in coverage between the states were identified. 20% (223) of women returned a consent form allowing validation of doses against the register and provider records: among these women 85.6% (538) of self reported doses were confirmed.

Conclusions

We confirmed that coverage rates for young women vaccinated in the community (at age 18–26 years) are underestimated by the national register and that under-notification is greater for second and third doses. Using 2011 population estimates, rather than estimates contemporaneous with the program rollout, reduces register-based coverage estimates further because of large population increases due to immigration since the program.     

Linked vaccination coverage surveys plus serosurveys among Ethiopian toddlers undertaken three years apart to compare coverage and serologic evidence of protection in districts implementing the RED-QI approach

In low and middle-income countries, estimating the proportion of vaccinated toddlers in a population is important for controlling vaccine-preventable diseases by identifying districts where immunization services need strengthening. Estimates measured before and several years after specific interventions can assess program performance. However, employing different methods to derive vaccination coverage estimates often yield differing results.MethodsLinked vaccination coverage surveys and seroprotection surveys performed among ~300 toddlers 12–23 months of age in districts (woredas), one per region, of Ethiopia (total, ~900 toddlers) in 2013 to estimate the proportion vaccinated with tetanus toxoid (a proxy for pentavalent vaccine) and measles vaccine. The surveys were followed by implementation of the Reaching Every District using Quality Improvement (RED-QI) approach to strengthen the immunization system.Linked coverage/serosurveys were repeated in 2016 to assess effects of the interventions on vaccination coverage. Indicators included “documented coverage” (vaccination card and/or health facility register records) and “crude coverage” (documented plus parent/caretaker recall for children without cards). Seroprotection thresholds were IgG-ELISA tetanus antitoxin ≥0.05 IU/ml and plaque reduction neutralization (PRN) measles titers ≥120 mIU/ml.FindingsImproved markers in 2016 over 2013 include coverage of pentavalent vaccination, vaccination timeliness, and fewer missed opportunities to vaccinate. In parallel, tetanus seroprotection increased in the 3 woredas from 59.6% to 79.1%, 72.9% to 83.7%, and 94.3 to 99.3%. In 2015, the Ethiopian government conducted supplemental measles mass vaccination campaigns in several regions including one that involved a project woreda and the campaign overlapped with the RED-QI intervention timeframe; protective measles PRN titers there rose from 31.0% to 50.0%.InterpretationThe prevalence of seroprotective titers of tetanus antitoxin (stimulated by tetanus toxoid components within pentavalent vaccine) provides a reliable biomarker to identify children who received pentavalent vaccine. In the three study woredas, the RED-QI intervention appeared to improve immunization service delivery, as documented by enhanced pentavalent vaccine coverage, vaccination timeliness, and fewer missed vaccination opportunities. A measles mass vaccination campaign was followed by a markedly increased prevalence of measles PRN antibodies. Collectively, these observations suggest that wider implementation of RED-QI can strengthen immunization, and periodic linked vaccination surveys/serosurveys can monitor changes.     

Geospatial variation in measles vaccine coverage through routine and campaign strategies in Nigeria: Analysis of recent household surveys

Measles vaccination campaigns are conducted regularly in many low- and middle-income countries to boost measles control efforts and accelerate progress towards elimination. National and sometimes first-level administrative division campaign coverage may be estimated through post-campaign coverage surveys (PCCS). However, these large-area estimates mask significant geographic inequities in coverage at more granular levels. Here, we undertake a geospatial analysis of the Nigeria 2017–18 PCCS data to produce coverage estimates at 1 × 1 km resolution and the district level using binomial spatial regression models built on a suite of geospatial covariates and implemented in a Bayesian framework via the INLA-SPDE approach. We investigate the individual and combined performance of the campaign and routine immunization (RI) by mapping various indicators of coverage for children aged 9–59 months. Additionally, we compare estimated coverage before the campaign at 1 × 1 km and the district level with predicted coverage maps produced using other surveys conducted in 2013 and 2016–17. Coverage during the campaign was generally higher and more homogeneous than RI coverage but geospatial differences in the campaign’s reach of previously unvaccinated children are shown. Persistent areas of low coverage highlight the need for improved RI performance. The results can help to guide the conduct of future campaigns, improve vaccination monitoring and measles elimination efforts. Moreover, the approaches used here can be readily extended to other countries.     

Beyond coverage: Rural-urban disparities in the timeliness of childhood vaccinations in Tanzania

BackgroundTimely vaccination maximizes efficacy for preventing infectious diseases. In the absence of national vaccination registries, representative sample survey data hold vital information on vaccination coverage and timeliness. This study characterizes vaccination coverage and timeliness in Tanzania and provides an analytic template to inform contextually relevant interventions and evaluate immunization programs.MethodsCross-sectional data on 6,092 children under age 3 from the 2015–16 Tanzania Demographic and Health Survey were used to examine coverage and timeliness for 14 vaccine doses recommended in the first year of life. The Kaplan-Meier method was used to model time to vaccination. Cox proportional hazard models were used to examine factors associated with timely vaccination.ResultsSubstantial rural–urban disparities in vaccination coverage and timeliness were observed for all vaccines. Across 14 recommended doses, documented coverage ranged from 52 % to 79 %. Median vaccination delays lasted up to 35 days; gaps were larger among rural than urban children and for later doses in vaccine series. Among rural children, median delays exceeded 35 days for the 3^rd doses of the polio, pentavalent, and pneumococcal vaccines. Median delays among urban children were < 21 days for all doses. Among rural and urban children, lower maternal education and delivery at home were associated with increased risk of delayed vaccination. In rural settings, less household wealth and greater distance to a health facility were also associated with increased risk of delayed vaccination.DiscussionThis study highlights persistent gaps in uptake and timeliness of childhood vaccinations in Tanzania and substantial rural–urban disparities. While the results provide an informative situation assessment and outline strategies for identifying unvaccinated children, a national electronic registry is critical for comprehensive assessments of the performance of vaccination programs. The timeliness measure employed in this study—the amount of time children are un- or undervaccinated—may serve as a sensitive performance metric for these programs.     

Social and demographic patterns of influenza vaccination coverage in Norway,influenza seasons 2014/15 to 2020/21

AimsTo examine influenza vaccination coverage among risk groups (RG) and health care workers (HCW), and study social and demographic patterns of vaccination coverage over time.MethodsVaccination coverage was estimated by self-report in a nationally representative telephone survey among 14 919 individuals aged 18–79 years over seven influenza seasons from 2014/15 to 2020/21. We explored whether belonging to an influenza RG (being >=65 years of age and/or having >=1 medical risk factor), being a HCW or educational attainment was associated with vaccination status using logistic regression.ResultsVaccination coverage increased from 27 % to 66 % among individuals 65–79 years, from 13 % to 33 % among individuals 18–64 years with >=1 risk factor, and from 9 % to 51 % among HCWs during the study period. Being older, having a risk factor or being a HCW were significantly associated with higher coverage in all multivariable logistic regression analyses. Higher education was also consistently associated with higher coverage, but the difference did not reach significance in all influenza seasons. Educational attainment was not significantly associated with coverage while coverage was at its lowest (2014/15–2017/18), but as coverage increased, so did the differences. Individuals with intermediate or lower education were less likely to report vaccination than those with higher education in season 2018/19, OR = 0.61 (95 % CI 0.46–0.80) and OR = 0.58 (95 % CI 0.41–0.83), respectively, and in season 2019/20, OR = 0.69 (95 % CI 0.55–0.88) and OR = 0.71 (95 % CI 0.53–0.95), respectively. When the vaccine was funded in the COVID-19 pandemic winter of 2020/21, educational differences diminished again and were no longer significant.ConclusionsWe observed widening educational differences in influenza vaccination coverage as coverage increased from 2014/15 to 2019/20. When influenza vaccination was funded in 2020/21, differences in coverage by educational attainment diminished. These findings indicate that economic barriers influence influenza vaccination decisions among risk groups in Norway.     

Coverage and timeliness of vaccination and the validity of routine estimates: Insights from a vaccine registry in Kenya

BackgroundThe benefits of childhood vaccines are critically dependent on vaccination coverage. We used a vaccine registry (as gold standard) in Kenya to quantify errors in routine coverage methods (surveys and administrative reports), to estimate the magnitude of survivor bias, contrast coverage with timeliness and use both measures to estimate population immunity.MethodsVaccination records of children in the Kilifi Health and Demographic Surveillance System (KHDSS), Kenya were combined with births, deaths, migration and residence data from 2010 to 17. Using inverse survival curves, we estimated up-to-date and age-appropriate vaccination coverage, calculated mean vaccination coverage in infancy as the area under the inverse survival curves, and estimated the proportion of fully immunised children (FIC). Results were compared with published coverage estimates. Risk factors for vaccination were assessed using Cox regression models.ResultsWe analysed data for 49,090 infants and 48,025 children aged 12–23 months in 6 birth cohorts and 6 cross-sectional surveys respectively, and found 2nd year of life surveys overestimated coverage by 2% compared to birth cohorts. Compared to mean coverage in infants, static coverage at 12 months was exaggerated by 7–8% for third doses of oral polio, pentavalent (Penta3) and pneumococcal conjugate vaccines, and by 24% for the measles vaccine. Surveys and administrative coverage also underestimated the proportion of the fully immunised child by 10–14%. For BCG, Penta3 and measles, timeliness was 23–44% higher in children born in a health facility but 20–37% lower in those who first attended during vaccine stock outs.ConclusionsStandard coverage surveys in 12–23 month old children overestimate protection by ignoring timeliness, and survivor and recall biases. Where delayed vaccination is common, up-to-date coverage will give biased estimates of population immunity. Surveys and administrative methods also underestimate FIC prevalence. Better measurement of coverage and more sophisticated analyses are required to control vaccine preventable diseases.     

Socioeconomic inequality trends in childhood vaccination coverage in India: Findings from multiple rounds of National Family Health Survey

ObjectivesThis article examines the inequality patterns in childhood vaccination coverage at various socio-economic levels using all four rounds of nationally representative National Family Health Surveys (NFHS) in India.MethodsThe analytic sample restricted to the most recent singleton surviving children aged 12–23 months in each survey, was 11,599 in NFHS‐1 (1992–93); 10,209 in NFHS‐2 (1998–99); 9582 in NFHS‐3 (2005–06) and 49,284 in NFHS‐4 (2015–16). Complete childhood vaccination is defined as a child aged 12–23 months who received one dose of BCG (Bacille Calmette Guerin), one dose of measles, and three doses each of DPT (Diphtheria, Pertussis, Tetanus), and polio vaccine (excluding the polio vaccine given at birth) at any time before the survey—according to the vaccination card or the mother’s recall. To understand inequalities in childhood vaccination, four measures were computed for each survey rounds’ data—absolute measures of inequality, the slope index of inequality (SII), and two relative measures: the ratio between the extreme groups and the concentration index (CIX) to see the degree of disparity.ResultsThe pro-rich and pro-education inequality in childhood vaccination coverage increased between 1998–99 and 2005–06 and declined considerably thereafter. This study found that inequality in childhood vaccination coverage has been minimized at a macro level such as rural-urban, male-female, religion, ethnicity, and in select geographies, but not universally at the micro-level. Findings indicate that pro-rich and pro-education inequalities were large among specific sub-groups of population: children in rural areas, children living in the northern region of the country and among scheduled tribes—as absolute and relative inequalities remained significantly high.ConclusionThese findings recommend robust program monitoring and policy-level support at the micro level to optimize the use of existing resources across all segments of the population in the country.     

Trends in influenza vaccination coverage rates in South Korea from 2005 to 2014: Effect of public health policies on vaccination behavior

BackgroundInfluenza is a major cause of morbidity and mortality worldwide. Annual vaccination is effective in its prevention and is recommended especially in susceptible populations such as the elderly over 65 years, children younger than 5, pregnant women, and people with chronic diseases. Overall, South Korea has a high vaccination rate owing to its National Immunization Program, although the method and extent of its coverage varies among the target subgroups. The aim of this study is to assess the trend of influenza vaccination coverage between 2005 and 2014 in South Korea to address the influence of sociodemographic and disease factors on vaccination behavior. Also, we aim to compare the vaccination coverage of target subgroups and evaluate the effect of relevant policies to provide suggestions for their improvement.MethodsA total of 61,036 respondents from the Korea National Health and Nutrition Examination Surveys III to VI were included.ResultsThe total influenza vaccination coverage increased from 38.0% in 2005 to 44.1% in 2014. Vaccination coverage was higher among the elderly aged ≥65 years (range, 70.0–79.8%; p-for-trend <0.001) and children under 5 (range, 64.6–78.9%; p-for-trend < 0.001) than among pregnant women (range, 9.4–37.8%; p-for-trend = 0.122) and people with chronic diseases (range, 29.6–42.6%; p-for-trend = 0.068) from 2005 to 2014. High vaccination coverage was associated with female gender, rural residence, low education level, high income, and increasing number of chronic diseases. But the effect of high income on high vaccination coverage was absent in the elderly aged ≥65 years and children under 5.ConclusionInfluenza vaccination rates have steadily increased from 2005 to 2014 in South Korea. Disparities between target groups correspond to their financial coverage under the National Immunization Program, and financial aids remove the influence of high income on higher vaccination rates. Future vaccination policies should focus on pregnant women and people with chronic diseases.     

Children vaccination coverage surveys: Impact of multiple sources of information and multiple contact attempts

BackgroundMonitoring vaccination coverage is an essential component of vaccination program evaluation. In Québec (Canada), children vaccination coverage surveys are conducted every two years since 2006. The objectives of this study were to evaluate the impact of supplementing data based on vaccination booklets with data from vaccine providers, on the final estimated vaccination coverage and to compare vaccination coverage between respondents to each survey contact attempt.MethodsData from six cross-sectional surveys were used, which included 3508 children aged 2 years. Parents were invited to transcribe the information available in their child’s vaccination booklet on the questionnaire received by mail. The survey included a maximum of 4 contact attempts to obtain a response. Data were completed among vaccine providers identified by parents. The main outcome was a complete vaccination status by 24 months of age.ResultsThe addition of data from vaccine providers to those present in vaccination booklets increased the proportion of children fully vaccinated from 5.5% to 23.7% depending on the survey year. The proportion of children fully vaccinated by 24 months of age estimated among respondents to contact 1 was only 2.1% higher than the estimates among all respondents.ConclusionsWithout validation among vaccine providers for children with missing doses according to vaccination booklets, results underestimated vaccination coverage in the target population. Conducting multiple contact attempts increased the response rate but had limited impact on the validity of estimates. It would be useful in future surveys to present the coverage obtain from respondents to each contact attempt.     

Impact of introduction of the 9-valent human papillomavirus vaccine on vaccination coverage of youth in North Carolina

ObjectivesThe objective of this study was to evaluate the impact of introduction of 9vHPV vaccine on HPV vaccination uptake (doses per capita) and initiation (≥1 doses), completion (≥3 doses) and compliance (≥3 doses within 12 months) by adolescents.MethodsWe used a retrospective cohort analysis using North Carolina Immunization Registry (NCIR) data from January 2008 through October 2016. The sample included Vaccines for Children eligible adolescents aged 9 to 17 years in 2016, for whom the NCIR contains complete vaccination history. We applied an interrupted time series design to measure associations between ZIP Code Tabulation Area (ZCTA)-level HPV vaccination outcomes over time with the introduction of 9vHPV in North Carolina (NC) in July 2015.ResultsEach outcome displayed a linear upward trend over time with large seasonal spikes near August of each year, corresponding to the time when adolescents often receive other vaccines required for school entry. After accounting for these underlying trends, introduction of 9vHPV was not associated with a change in publicly funded HPV vaccination rates in NC.ConclusionsOur results indicate that 9vHPV substituted for 4vHPV in the first year after release in NC, but the release of 9vHPV was not associated with an overall change in HPV vaccination.     

Influenza vaccination of hospital staff in Germany: a five-year survey on vaccination coverage and policies: identified deficits in influenza immunisation campaigns for hospital employees

Summary. Objectives: Influenza vaccination of hospital staff is recommended by STIKO, the German committee for vaccination. A survey was conducted to assess compliance with this recommendation. The occupational health services of 25 hospitals participated in a survey and provided data by questionnaire on influenza vaccination and on hospital policies to promote coverage of employees.Methods: Vaccination activities were monitored by occupational health services (OHS) for five consecutive years from 1997 to 2002. The hospital sample covered a total of 17089 beds (3.23% of the hospital capacity in Germany) and a total number of 41969 employees (4.39% of hospital staff).Results: The proportion of hospitals actively offering influenza vaccination increased from 48% in 1997/98 to 92% in 2001/02. Vaccination coverage of all staff in 1997 was only 3.3% and reached 8.4% in 2001/02. Coverage of vaccinating hospitals increased from 5.0% to 10.4%. Poster campaigns and managing board commitment had significant impact.Conclusions: Considerable progress has been made to involve more hospitals and to increase coverage for vaccination of hospital employees. Nevertheless, coverage levels remain unacceptably low. Recommendations are ignored extensively.

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Zusammenfassung. Influenzaimpfung von Krankenhauspersonal in Deutschland: eine Fünfjahresuntersuchung zu Durchimpfungsraten, Impfpolitik und -defiziten in 25 deutschen KrankenhäusernFragestellung: Die Impfung von Krankenhauspersonal gegen Influenza wird von der Ständigen Impfkommission (STIKO) empfohlen. Die Umsetzung dieser Empfehlung in deutschen Krankenhäusern wurde untersucht. Die Betriebsärzte von 25 Krankenhäusern nahmen an einer Umfrage teil, für die sie Daten ihres jeweiligen Hauses zur Influenzaimpfung und Impfpolitik bereitstellten.Methode: Die Untersuchung fand in fünf aufeinander folgenden Jahren (1997–2002) statt. Die Stichprobe umfasste insgesamt 17089 Betten (3,23% der gesamten deutschen Bettenkapazität) und 41969 Angestellten (4,39% des deutschen Krankenhauspersonals).Ergebnisse: Der Anteil der impfenden Krankenhäuser stieg von 48% in der Saison 1997/98 auf 92% in 2001/02. Die Durchimpfungsrate lag 1997 bei nur 3,3% und 2001/02 erreichte sie 8,4%. Die Impfrate in impfenden Krankenhäusern stieg im gleichen Zeitraum von 5,0% auf 10,4%. Poster-Kampagnen und Einbeziehung der Krankenhausleitung haben signifikanten Einfluss.Schlussfolgerung: Es zeigt sich eine deutliche Steigerung sowohl der Krankenhäuser mit Impfangebot als auch der Durchimpfungsrate des Krankenhauspersonals. Nichtsdestotrotz bleibt diese aber auf einem nicht akzeptabel niedrigem Niveau.

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Résumé. Vaccination contre la grippe du personnel hospitalier en Allemagne: une recherche de cinq ans sur les taux de vaccination et la politique appliquée en matière de vaccination dans 25 hôpitaux allemandsObjectifs: La vaccination du personnel hospitalier contre la grippe est recommandée par la Commission permanente de la vaccination du Robert Koch Institut. Cette étude a porté sur lapplication de cette recommandation dans les hôpitaux allemands. Les médecins du travail de 25 hôpitaux ont participé à une enquête dans le cadre de laquelle ils ont fourni les données suivantes: prévalence de la vaccination contre la grippe et méthodes de promotion de la vaccination.Méthodes: Lenquête a eu lieu cinq années consécutives (1997–2002). Elle a porté sur 25 hôpitaux, soit sur 41969 employés (4,39% du personnel hospitalier allemand).Résultats: La proportion dhôpitaux pratiquant la vaccination est passée de 48% pour la période 1997/98 à 92% pour 2001/02. En 1997, le taux de vaccination ne sélevait quà 3,3% pour atteindre 8,4% en 2001/02. Le taux de vaccination dans les hôpitaux pratiquant déjà la vaccination en 1997 est passé durant la même période de 5,0% à 10,4%. Limplication de la direction hospitalière ainsi que le recours à des affiches ont eu un impact significatif.Conclusions: Le nombre dhôpitaux proposant la vaccination, ainsi que le taux de vaccination ont nettement augmenté. Néanmoins, ce taux reste à un niveau inacceptablement bas.

     

The effects of switching from 10 to 5-dose vials of MR vaccine on vaccination coverage and wastage: A mixed-method study in Zambia

IntroductionVaccines procured for low-income countries are often packaged in multi-dose vials to reduce program costs. To avoid wastage, health workers may refrain from opening a vial if few children attend an immunization session, possibly leading to lower coverage. Lowering the number of doses in a vial may increase coverage and reduce wastage.MethodsWe used a mixed methods approach to measure the effects of switching from conventional 10-dose measles containing vaccine (MCV) vials to 5-dose MCV vials on coverage and open vial wastage in 14 districts purposely selected from two provinces in Zambia. The districts were paired based on the number of health facilities and the average size of the health facility catchment population. One district from each pair was randomly allocated to receive 5-dose vials while the other continued with the conventional vials. We applied propensity score matched difference-in-difference analysis to estimate intervention effects on coverage using pre-intervention household survey and post-intervention household survey after 11 months of the intervention. The intervention effects on wastage rates were estimated from multivariate analysis of the administrative data. Key informant interviews were conducted to better understand health workers’ behavior and preferences at baseline, midline and endline, and analyzed using thematic analysis techniques.ResultsMCV coverage rates increased across both arms for both doses. A five percentage-point intervention effect was detected for MCV1 and 3.5 percentage-point effect for MCV2. The MCV wastage rate was 47% lower in facilities using 5-dose vials (16.2%) versus 10-dose vials (30.5%). Healthcare workers reported being more willing to open a 5-dose vial than a 10-dose vial for one child, as they were less concerned about wastage.DiscussionSwitching 10-dose MCV vials to 5-dose vials improved coverage, decreased wastage, and improved willingness to open a vial. These findings can contribute to strategies for reducing missed opportunities for vaccination.     

Consequences of household air pollution on child survival: evidence from demographic and health surveys in 47 countries

Background: Over one-third of the world’s population is exposed to household air pollution (HAP) but the separate effects of cooking with solid fuel and kerosene on childhood mortality are unclear.

Objectives: To evaluate the effects of both solid fuels and kerosene on neonatal (0-28 days) and child (29 days-59 months) mortality.

Methods: We used Demographic and Health Surveys from 47 countries and calculated adjusted relative risks (aRR) using Poisson regression models.

Results: The aRR of neonatal and child mortality in households exposed to solid fuels were 1.24 (95% CI: 1.14, 1.34) and 1.21 (95% CI: 1.12, 1.30), respectively, and the aRR for neonatal and child mortality in households exposed to kerosene were 1.34 (95% CI: 1.18, 1.52) and 1.12 (95% CI: 0.99, 1.27), controlling for individual, household, and country-level predictors of mortality.

Conclusions: Kerosene should not be classified as a clean fuel. Neonates are at risk for mortality from exposure to solid fuels and kerosene.     

Consequences of household air pollution on child survival: evidence from demographic and health surveys in 47 countries

Background: Over one-third of the world’s population is exposed to household air pollution (HAP) but the separate effects of cooking with solid fuel and kerosene on childhood mortality are unclear.Objectives: To evaluate the effects of both solid fuels and kerosene on neonatal (0-28 days) and child (29 days-59 months) mortality.Methods: We used Demographic and Health Surveys from 47 countries and calculated adjusted relative risks (aRR) using Poisson regression models.Results: The aRR of neonatal and child mortality in households exposed to solid fuels were 1.24 (95% CI: 1.14, 1.34) and 1.21 (95% CI: 1.12, 1.30), respectively, and the aRR for neonatal and child mortality in households exposed to kerosene were 1.34 (95% CI: 1.18, 1.52) and 1.12 (95% CI: 0.99, 1.27), controlling for individual, household, and country-level predictors of mortality.Conclusions: Kerosene should not be classified as a clean fuel. Neonates are at risk for mortality from exposure to solid fuels and kerosene.     

2017-2021年中国肠道病毒71型灭活疫苗接种现状分析

目的了解2017-2021年中国肠道病毒71型(EV71)灭活疫苗接种现状, 为制定手足口病防控和免疫策略提供参考。方法利用中国免疫规划信息管理系统收集的EV71灭活疫苗报告接种剂次数和出生人口数据估算2012年以来各出生队列截至2021年底的全国、分省和分地市EV71灭活疫苗累计接种率, 并分析与接种率水平相关的潜在影响因素。结果截至2021年, 全国2012年以来出生队列EV71灭活疫苗估算累计接种率为24.96%, 各省份估算接种率为3.09%～56.59%, 各地市估算接种率为0～88.17%。不同地区疫苗接种率与该地区既往手足口病报告发病水平和人均可支配收入的相关性均有统计学意义。结论 2017年以来EV71灭活疫苗在全国范围内应用广泛, 但地区间疫苗接种覆盖情况差异较大, 经济相对发达地区接种率较高, 既往疾病流行强度可能对疫苗的接受度和接种服务模式产生一定影响。EV71灭活疫苗接种对手足口病流行的影响还需进一步研究。