Vaccination Coverage Survey Research Articles

Japanese Encephalitis Mass Vaccination Coverage Survey in Five Districts of Nepal

Introduction: The World Health Organization recommends mass vaccination campaigns in children under 15 years before introducing the Japanese Encephalitis (JE) vaccine into the routine immunization program as the most effective immunization strategy in JE disease-endemic countries. The study was conducted to assess the JE vaccine coverage during the recent mass vaccination campaign in five districts of Nepal in 2016.
 Methods: A stratified three-stage cluster design was used for this cross-sectional sample survey. The JE mass vaccination campaign of 2016 targeted children aged between 1-14 years, and the interview was conducted among systematically sampled households’ mothers and guardians of children aged between 2-15 years in 2017.
 Results: The coverage of the JE mass vaccination campaign in the year 2016 was 96.9%; the males had slightly higher coverage (97.4%) than females (96.6%). The vaccine utilization increased with an increase in age, 94.0%, 98.1%, and 99.1% coverage among children aged 2-5 years, 6-10 years, and 10-15 years, respectively. The school enrolled children were four-times (OR: 4.016, CI: 2.595–6.216) likely to be vaccinated than out-of-school children and association was statistically significant. Among 86 children who were not vaccinated, 45.3% were ill during the campaign. Besides, 6.6% of out of school children also didn’t get the vaccination. Only three in ten (30.4%) respondents knew that the JE vaccine was given to protect against JE disease or brain fever. More than one-third (36.3%) of respondents reported that the recommendation from the health workers was main reason for vaccinating their children. Only 1.1% of vaccinated children had minor issues following vaccination.
 Conclusion: Despite low awareness about the specific protection of the JE vaccine, the vaccination coverage was high during the JE mass vaccination campaign. Increasing awareness about the particular vaccine and including activities to vaccinate out-of-school children could help achieve universal coverage in future mass vaccination campaigns

Epidemiological characteristics of Under Five Measles cases, Al Najaf Al Ashraf Province, Iraq, 2006-2018

Background: Measles is a highly contagious disease and it is one of leading causes of death among young children. In Iraq, extensive efforts are in place to achieve measles elimination but still sporadic cases and limited outbreaks continued to occur. 
 Aim of the study: to describe epidemiological characteristics of under five years measles cases and determine the risk factors of measles in Al Najaf Al Ashraf province, Iraq, 2006-2018. 
 Methodology: This study follows a retrospective descriptive design, which was conducted in the period from 1 January, 2006 to 31 of December of 2018, Review of surveillance records of all suspected measles cases reported to Al Najaf Ashraf Directorate of Health from 2006 to 2018. Basic demographic data, vaccination status and lab results were sought. 
 Results: Total suspected measles cases during this period was 418; 196(47%) were males; median age was 24 months; and 219 (52%) live in urban areas. Only 201 (48%) had at least one dose of measles vaccine; 112 (56%) of vaccinated children live in urban area. Lab results were available for all the cases, 202(48%) were measles IgM positive. Of the lab confirmed cases, 105 (52%) lived in rural area and 158(78%) reported in 2009. Comparing lab confirmed cases with others, un-vaccination to measles vaccine was the only statistically significant risk factor (P=0.001; odds ratio=1.87; 95% CI: 1.27- 2.75). 
 Conclusion: Although this is not a vaccine coverage survey, but we found that measles vaccine coverage is extremely low that increase risk of outbreaks.
 Recommendations: improvement of routine immunization coverage and intensified measles campaign are recommended. 

Evaluating the vaccination coverage: validity of household-hold vaccination booklet and caregiver’s recall

ABSTRACT Background We compared results from household data sources to medical record sources by using data from a vaccination coverage survey. Methods Vaccination coverage (VC) was calculated based on parental recall, household vaccination booklet, and Zhejiang provincial immunization information system (ZJIIS). We evaluated the accuracy of VC based on household sources (vaccination booklet and recall) assuming the medical record was accurate. Concordance, sensitivity, specificity, positive predictive value, and negative predictive value were estimated as well as the Kappa statistic was also used to evaluate the agreement between data sources. Results Among the 1,800 children identified in the household survey, all were registered in ZJIIS. VC estimated using the vaccination booklet alone was substantially lower than that based on medical records (net bias 3.4–16.7% in different age groups). VC based on parental recall ranged from 2.5% below (among children aged 1 year) to 16.7% points above (among children aged 6 years) than those based on medical records. Concordance was lowest for card estimates (32.5–45.5%). Sensitivity was <60% for all household sources, except for recall source. Specificity was lowest for recall estimates (14.5–42.6%). Positive predictive value was >75%, while negative predictive value was <50%, for all household sources. Kappa statistics generally indicated poor agreement between household and medical record sources. Conclusions Household-retained vaccination booklets and parental recall were insufficient sources for evaluating the VC. Our findings emphasized the importance of taking interventions to make the vaccination booklet more consistent with the records from medical resource.

Implementing WHO guidance on conducting and analysing vaccination coverage cluster surveys: Two examples from Nigeria.

In 2015, the World Health Organization substantially revised its guidance for vaccination coverage cluster surveys (revisions were finalized in 2018) and has since developed a set of accompanying resources, including definitions for standardized coverage indicators and software (named the Vaccination Coverage Quality Indicators-VCQI) to calculate them.-The current WHO vaccination coverage survey manual was used to design and conduct two nationally representative vaccination coverage surveys in Nigeria-one to assess routine immunization and one to measure post-measles campaign coverage. The primary analysis for both surveys was conducted using VCQI. In this paper, we describe those surveys and highlight some of the analyses that are facilitated by the new resources. In addition to calculating coverage of each vaccine-dose by age group, VCQI analyses provide insight into several indicators of program quality such as crude coverage versus valid doses, vaccination timeliness, missed opportunities for simultaneous vaccination, and, where relevant, vaccination campaign coverage stratified by several parameters, including the number of previous doses received. The VCQI software furnishes several helpful ways to visualize survey results. We show that routine coverage of all vaccines is far below targets in Nigeria and especially low in northeast and northwest zones, which also have highest rates of dropout and missed opportunities for vaccination. Coverage in the 2017 measles campaign was higher and showed less geospatial variation than routine coverage. Nonetheless, substantial improvement in both routine program performance and campaign implementation will be needed to achieve disease control goals.

Pairs of independent nationally representative vaccination coverage surveys conducted within one year of each other: A global overview covering 2000–2019

BackgroundPopulation-based surveys play an important role in measuring vaccination coverage. Surveys measuring vaccination coverage may be commissioned by the Expanded Programme on Immunization (EPI surveys) or part of multi-domain non-EPI surveys such as Demographic and Health Surveys (DHS) or Multiple Indicator Cluster Surveys (MICS). Surveys conducted too close in time to each other may not only be an inefficient use of resources but may also create problems for programme staff when results suggest inconsistent patterns of programme performance for similar time periods. ObjectiveTo summarize the occurrence of vaccination coverage surveys conducted close in time during 2000–2019 and compare results of EPI and non-EPI coverage surveys when the surveys were conducted within one year of each other. MethodsUsing a database of published national-level vaccination coverage survey results compiled by the World Health Organization (WHO) and the United Nations Children’s Fund (UNICEF), the authors abstracted information on survey field work dates, sample size, percentage of children with documented history of vaccination and the percent coverage, as well as published uncertainty intervals from DHS and MICS, for the first and third doses of diphtheria-tetanus toxoid-pertussis containing vaccine (DTP1, DTP3) and first dose of measles containing vaccine (MCV1). Survey results of EPI and non-EPI surveys were compared. ResultsThe authors identified 646 surveys with final reports and estimates of national-level vaccination coverage for DTP1, DTP3, or MCV1 from a total of 687 surveys with data collection start date from 2000 to 2019. Of the 140 countries with at least one vaccination coverage survey, a median of four surveys was observed. Most countries were Gavi-eligible and located in the WHO Africa Region. Sixty-six survey dyads were identified where an EPI survey occurred within one year of a non-EPI survey. For the 66 dyads, in 49 of 59 with information available, EPI surveys reported higher proportion of documented evidence of vaccination and EPI survey results tended to suggest higher levels of vaccination coverage compared to the non-EPI surveys; quite often, differences were substantial. Surveys that found higher proportions of children with documented vaccination evidence tended to also find higher proportions of children who had been vaccinated. SummaryOpportunities exist to improve overall planning of vaccination coverage measurement in population-based household surveys so that both EPI and non-EPI surveys are more comparable and survey coverage estimates are more appropriately spaced in time. When surveys occur too close in time, careful attention is warranted to ensure comparability and assess sources of documented evidence of vaccination and related coverage differences.

Impact of National Introduction of Ten-Valent Pneumococcal Conjugate Vaccine on Invasive Pneumococcal Diseases in Bangladesh: Case-Control and Time-Trend Studies

Background: Bangladesh introduced the ten-valent pneumococcal conjugate vaccine (PCV10) in its national immunization program on March 2015 creating an opportunity to assess the real-world impact of PCV on invasive pneumococcal diseases (IPD). Methods: Between January 2014 and June 2018, children aged 3-35 months in Sylhet district of Bangladesh were visited every two months to collect morbidity and care-seeking data. Children attending sub-district hospitals with pneumonia, meningitis, or sepsis were assessed for IPD after obtaining informed consent. Blood and cerebrospinal fluid were collected from enrolled children to isolate pneumococcus using culture and molecular tests. Vaccine-eligible children with pneumococcus isolated were enrolled as cases. Four age and sex-matched clinic and community controls were selected for each case within two weeks of case identification. Data on immunization status and confounders were collected. PCV coverage was estimated using vaccine coverage surveys. Case-control and incidence trend analyses were conducted to assess the impact of PCV on IPD. Results: The community cohort yielded 217,605 child years of observations and 46,013 child-visits to study hospitals. Pneumococcus was isolated from 44 children who were age-eligible to receive PCV; these children were enrolled as cases. The cases were matched with 166 community- and 150 clinic-controls. The matched case-control analyses using community-controls showed 83% effectiveness (95% CI: 1.57% to 97.1%) and clinic controls showed 90% effectiveness (95% CI: -26.0% to 99.1%) in preventing IPD. Incidence trend analysis estimated vaccine effectiveness at 80.1% (95% CI: 38.4, 93.6). Conclusion: PCV in this pediatric population in Bangladesh was highly effective in preventing IPD. Funding Information: This study was funded by the Bill & Melinda Gates Foundation [OPP1084286, OPP1117483] and GlaxoSmithKline [90063241]. Declaration of Interests: None to declare. Ethics Approval Statement: The protocol was approved by the institutional review board of the International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b) in Dhaka, Bangladesh (PR-13095) and the Johns Hopkins Bloomberg School of Public Health in Baltimore, Maryland, USA (IR5421).

Measles outbreak investigation in village Miranshah, North Waziristan Agency, Pakistan February 2018: A case control study

Background: Measles is highly contagious and remains a leading cause of childhood mortality. Outbreak of Measles were reported from various parts of Pakistan, particularly tribal areas. In February 2018 Measles outbreak was reported from Miranshah North Waziristan Agency. Purpose: To confirm the outbreak, asses its magnitude, identify risk factors and to implement prevention and control activities to stop spread of the outbreak. Methods and materials: A case was defined as “Rash with fever and cough, coryza or conjunctivitis in a child younger than 14 year of age, resident of Miranshah, during 3rd February to 15th March, 2018.”Active search of cases done. Data was collected using pretested structured questionnaire and analyzed using Epi Info version 7.1.Descriptive analysis was done followed by age & sex matched case control study. Case fatality rate, attack rate, vaccine efficacy and secondary infectivity rate were calculated. Results: Total 42 cases were identified. The Epi curve ranges from 3rd February to 15th March with a bi-modal peak on 23rd February and 5th March. Mean age of the cases was 37 months (range 1–120 months). Males were 52.38% (n = 22). Socioeconomic status of parents was poor (28.57% laborers, 38.10% earn below 10000 PKR/month, 59% fathers were illiterate). Case fatality rate was 7.14% (n = 3).Vaccination showed protective effect [OR 0.12 (95% CI:0.03–0.40, P < 0.05)].Vaccination coverage survey showed 46.3% coverage for measles-1.Secondary infectivity was high in houses where children were more than 7 in number [OR 8.67 (95% CI: 1.76–42.6, P < 0.05).Distance from health facility (>3Kms) showed higher odds of getting the illness [OR 2.89 (95% CI:1.22–6.84, P < 0.05]. Conclusion: This study in a post conflict repatriated population showed relationship of low socioeconomic status, low vaccination coverage, distance from health facility and overcrowding with the disease. Awareness sessions and mop-up vaccination in the area contributed in controlling the outbreak.

How much does it cost to measure immunity? A costing analysis of a measles and rubella serosurvey in southern Zambia.

Serosurveys are a valuable surveillance tool because they provide a more direct measure of population immunity to infectious diseases, such as measles and rubella, than vaccination coverage estimates. However, there is concern that serological surveys are costly. We adapted a framework to capture the costs associated with conducting a serosurvey in Zambia. We costed a nested serosurvey in Southern Province, Zambia that collected dried blood spots from household residents in a post-campaign vaccine coverage survey. The financial costs were estimated using an ingredients-based costing approach. Inputs included personnel, transportation, field consumable items, social mobilization, laboratory supplies, and capital items, and were classified by serosurvey function (survey preparation, data collection, biospecimen collection, laboratory testing, and coordination). Inputs were stratified by whether they were applicable to surveys in general or attributable specifically to serosurveys. Finally, we calculated the average cost per cluster and participant. We estimated the total nested serosurvey cost was US $68,558 to collect dried blood spots from 658 participants in one province in Zambia. A breakdown of the cost by serosurvey phase showed data collection accounted for almost one third of the total serosurvey cost (32%), followed by survey preparation (25%) and biospecimen collection (20%). Analysis by input categories indicated personnel costs were the largest contributing input to overall serosurvey costs (51%), transportation was second (23%), and field consumables were third (9%). By combining the serosurvey with a vaccination coverage survey, there was a savings of $43,957. We estimated it cost $4,285 per average cluster and $104 per average participant sampled. Adding serological specimen collection to a planned vaccination coverage survey provided a more direct measurement of population immunity among a wide age group but increased the cost by approximately one-third. Future serosurveys could consider ways to leverage existing surveys conducted for other purposes to minimize costs.

The trends of socioeconomic inequities in full vaccination coverage among children aged 12–23 months from 2000 to 2017: evidence for mitigating disparities in vaccination service in Zhejiang province

ABSTRACT Objective This study aimed to evaluate the trends and changes in inequities in the completeness of the primary vaccination (CPV) scheduled before the first year of age among children aged 12–23 months, from 2000 to 2017. Methods: Data were extracted from five rounds of the provincial vaccination coverage survey (PVCS) in 2000, 2004, 2008, 2014 and 2017, respectively. The household income per month was used as an index of socioeconomic status for the inequity analysis. The concentration index (CI) was used to quantify the degree of inequity, and the decomposition approach was applied to quantify the contributions from independent factors to inequity in the CPV. Results: The CPV was significantly improved from 2000 to 2017, with 67.0% for the 2000 PVCS and 86.0% for the 2017 PCVS. The CI value decreased from 0.29839 for the 2000 round to 0.03601 for the 2017 round. The decomposition analysis indicated that independent variables such as birth order, ethnic group, mother’s education, maternal employment status, residence, immigration status and the percentage of the total health spending allocated to public health could explain the inequity in the CPV in varying degrees. Conclusions: A sharp reduction in socioeconomic inequity in the CPV was observed from 2000 to 2017. Policy recommendations to reduce the inequality in the CPV should focus on children with the risk factors found in this study, for better outcome in full vaccination and long-lasting herd immunity.

Immunization of Mothers of Children with Cerebral Palsy in Rural Bangladesh.

Vaccination is one of the most effective public health tools for the prevention of infectious diseases, morbidity and disability. Little is known about the rate of maternal immunization among mothers of children with Cerebral Palsy (CP), as well as any possible role of maternal immunization in development of CP in the newborns. To determine the socio-demographic characteristics and self-reported vaccination status of mothers of children with CP and compare vaccination coverage in this cohort with national data on immunization. The study also aims to assess the vaccination status of children with CP. A subset of the Bangladesh CP Register (BCPR) cohort of women who had children with CP were recruited during April 2017 from a community based early intervention and rehabilitation program going on in Shahjadpur. Socio-demographic characteristics and maternal immunization status were assessed using a semi-structured questionnaire. The vaccination status of the children was also assessed by interviewing mother and observing the BCG marks. All data were compared with the corresponding information among general population using national vaccination coverage survey reports of the Ministry of Health and Family Welfare, Bangladesh. Sixty-eight mothers were interviewed of which 17.6% of mothers reported not receiving any vaccine during pregnancy. Tetanus vaccine was most commonly (82.0%) received during pregnancy. Overall coverage for at least two doses of tetanus toxoid (TT) among mothers of children with CP was significantly lower than the national tetanus coverage (79.4% versus 96.4%, p<0.01). Forty-two (61.7%) mothers with a child with CP reported having not received tetanus vaccine during their pregnancy compared to only twenty (29.4%) mothers with healthy children reported missing tetanus vaccination during their pregnancy. This difference was statistically significant (p<0.01). Hepatitis B and influenza vaccine were received by mothers of children with CP during the antenatal period (2 and 6 respectively). Immunization among mothers of children with CP is significantly poorer than the national coverage. Also, the immunization of the children with CP is poorer than the national EPI coverage. Our findings reflect the necessity for specific strategies to improve the vaccination coverage among mothers of children with disabilities especially CP and the children with CP.

Pneumococcal vaccination coverage in France by general practitioners in adults with a high risk of pneumococcal disease

ABSTRACT Streptococcus pneumoniae, the main cause of community-acquired pneumonia (CAP), also leads to exacerbations, hospitalizations, and mortality in chronic obstructive pulmonary disease (COPD) and congestive heart failure (CHF). The risk of CAP is increased in patients with diabetes mellitus (DM), and the risk of invasive pneumococcal disease is increased in HIV-infected patients. Pneumococcal vaccination is recommended for these patients in France. The objective was a large survey of pneumococcal vaccination coverage (PVC) by general practitioners (GPs) in these patients in France. Diagnosis and treatment forms were extracted from the database of 2000 GPs. The GPs and population panels were representative of the metropolitan populations. The primary endpoint was the comparison of PVC in the adult patients diagnosed with COPD, CHF, DM, or HIV infection during the study (April 2013–April 2017) and the control (March 2012–March 2013) periods. Of the 17,865 and 4,690 patients identified, 756 (4%) and 267 (6%) were vaccinated, respectively. During the study period, the PVC was significantly higher (35/282, 12%) in HIV-infected patients and lower in patients with DM (95/5994, 2%) than in other patients. Even though French pneumococcal vaccine recommendations in adults were updated in 2013, the PVC did not increase according to the years of the study period and slightly increased according to time after diagnosis. S. pneumoniae is responsible only for some CAP and meningitis, and incomplete protection by vaccine, hesitancy from practitioners and patients, and the moving schedule of vaccination could explain the results. New tools and/or strategies must be implemented to increase PVC in France. Abbreviations: CAP: community-acquired pneumonia; COPD: chronic obstructive pulmonary diseases; CHF: congestive heart failure; DM: diabetes mellitus; IPD: invasive pneumococcal disease; HIV: human immunodeficiency virus; PVC: pneumococcal vaccination coverage; PCV7: 7-valent pneumococcal conjugate vaccine; PCV13: 13-valent pneumococcal conjugate vaccine; PPSV23: 23-valent pneumococcal polysaccharide vaccine; GPs: general practitioners; CLM: Cegedim Logiciels Médicaux; MLM: monLogicielMedical; ICD-10: International Classification of Diseases; CNIL: Commission nationale de l’informatique et des libertés; HPV: human papillomavirus; HBV: hepatitis B virus

Vaccination coverage survey and seroprevalence among forcibly displaced Rohingya children, Cox's Bazar, Bangladesh, 2018: A cross-sectional study.

BackgroundDuring August 2017–January 2018, more than 700,000 forcibly displaced Rohingyas crossed into Cox’s Bazar, Bangladesh. In response to measles and diphtheria cases, first documented in September and November 2017, respectively, vaccination campaigns targeting children <15 years old were mobilized during September 2017–March 2018. However, in a rapidly evolving emergency situation, poor sanitation, malnutrition, overcrowding, and lack of access to safe water and healthcare can increase susceptibility to infectious diseases, particularly among children. We aimed to estimate population immunity to vaccine-preventable diseases (VPDs) after vaccination activities in the camps to identify any remaining immunity gaps among Rohingya children.Methods and findingsWe conducted a cross-sectional serologic and vaccination coverage survey in Nayapara Registered Refugee Camp (“Nayapara”) and makeshift settlements (MSs) April 28, 2018 to May 31, 2018, among 930 children aged 6 months to 14 years. MSs are informal, self-settled areas with a population of more than 850,000, the majority of whom arrived after August 2017, whereas Nayapara is a registered camp and has better infrastructure than MSs, including provision of routine immunization services. Households were identified using simple random sampling (SRS) in Nayapara and multistage cluster sampling in MSs (because household lists were unavailable). Dried blood spots (DBSs) were collected to estimate seroprotection against measles, rubella, diphtheria, and tetanus, using Luminex multiplex bead assay (MBA). Caregiver interviews assessed vaccination campaign participation using vaccination card or recall. In Nayapara, 273 children aged 1 to 6 years participated; 46% were female and 88% were registered refugees. In MSs, 358 children aged 1 to 6 years and 299 children aged 7 to 14 years participated; 48% of all children in MSs were female, and none were registered refugees. In Nayapara, estimated seroprotection among 1- to 6-year-olds was high for measles, rubella, diphtheria, and tetanus (91%–98%; 95% confidence interval [CI] 87%–99%); children >6 years were not assessed. In MSs, measles seroprotection was similarly high among 1- to 6-year-olds and 7- to 14-year-olds (91% [95% CI 86%–94%] and 99% [95% CI 96%–100%], respectively, p < 0.001). Rubella and diphtheria seroprotection in MSs were significantly lower among 1- to 6-year-olds (84% [95% CI 79%–88%] and 63% [95% CI 56%–70%]) compared to 7- to 14-year-olds (96% [95% CI 90%–98%] and 77% [95% CI 69%–84%]) (p < 0.001). Tetanus seroprevalence was similar among 1- to 6-year-olds and 7- to 14-year-olds (76% [95% CI 69%–81%] and 84% [95% CI 77%–89%], respectively; p = 0.07). Vaccination campaign coverage was consistent with seroprotection in both camps. However, nonresponse, the main limitation of the study, may have biased the seroprotection and campaign coverage results.ConclusionsIn this study, we observed that despite multiple vaccination campaigns, immunity gaps exist among children in MSs, particularly for diphtheria, which requires serial vaccinations to achieve maximum protection. Therefore, an additional tetanus-diphtheria campaign may be warranted in MSs to address these remaining immunity gaps. Rapid scale-up and strengthening of routine immunization services to reach children and to deliver missed doses to older children is also critically needed to close immunity gaps and prevent future outbreaks.

An Internet-Based Survey of Influenza Vaccination Coverage in Healthcare Workers in China, 2018/2019 Season.

Influenza vaccination coverage was low among healthcare workers (HCWs) in China. In October 2018, the National Health Commission of China began to require all hospitals to provide free influenza vaccination for HCWs to increase vaccine uptake, and no study on vaccine coverage among HCWs at the national level after the announcement of new policy. This evaluation aims to investigate self-reported influenza vaccination coverage among HCWs and factors that may affect vaccine receipt during the 2018/2019 influenza season. We delivered an opt-in internet panel survey among registered HCWs of DXY forum (the biggest online forum for HCWs in China). The survey was self-administered using a standard questionnaire to collect information on demographics, occupational characteristics, policy implementation, influenza vaccination and influence factors. We conducted multivariate logistic regression analysis to assess factors associated with receipt of influenza vaccine. The response rate of this online survey was 3.6%. The seasonal influenza vaccine coverage reported among HCWs surveyed during the 2018/2019 season was 11.6% (472/4078). Only 19.0% (774/4078) of HCWs surveyed reported free policy in their workplace. Combing free policy and workplace requirement proved to be effective to improve influenza vaccination coverage in HCWs (PR = 6.90, 95% CI: 6.03–7.65). The influenza vaccination coverage among surveyed HCWs in China was low during the 2018/2019 season. To increase future vaccination uptake, we recommend a multi-faceted strategy that include free policy, workplace requirement and promotion, on-site vaccination, and monitoring.

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.

Development of a high number, high coverage dog rabies vaccination programme in Sri Lanka

BackgroundRabies is estimated to cause 59,000 deaths and economic losses of US$8.6 billion every year. Despite several years of rabies surveillance and awareness programmes, increased availability of post-exposure prophylaxis vaccinations and dog population control, the disease still remains prevalent in Sri Lanka. This study reports the roll-out of a high number, high coverage canine rabies vaccination campaign in Sri Lanka, providing estimates for the vaccination coverage achieved, analysing the local dog demographics, and identifying barriers of attendance to static vaccination clinics.MethodsA mass dog vaccination campaign was undertaken in Negombo, Sri Lanka. The campaign was composed of static point and door-to-door vaccination stages, with a final survey of vaccination coverage. A large volume of data on the distribution, health, and signalment of vaccinated dogs was collected through a mobile phone application. A logistic regression model was developed to investigate which socio-spatial and dog-related factors influenced attendance of owners to static vaccination points.ResultsThe campaign vaccinated over 7800 dogs achieving a vaccination coverage of 75.8%. A dog:human ratio of 1:17 was estimated. Most dogs were owned, and the dog population was mostly male, adult, and non-sterilized. Unawareness, unavailability and handling problems were the most common reasons given by owners to explain failure to attend a static vaccination point. The regression analysis showed that increasing distance to a static point, in addition to young age and poor health of the dog, were associated with a decrease in the likelihood of attendance to a static vaccination points.ConclusionThis study demonstrates the feasibility of high number, high coverage vaccination campaigns in Sri Lanka. The information on dog ecology and barriers of attendance to static point vaccination clinics will facilitate development of future vaccination campaigns.

Using Serosurvey Data Triangulation for More Accurate Estimates of Vaccine Coverage: Measured and Modeled Coverage From Pakistan Household Surveys.

Household surveys remain an essential method for estimating vaccine coverage in developing countries. However, the resulting estimates have inevitable and currently unmeasurable information biases due to inaccuracies in recall, low retention of home-based records (HBRs; i.e., vaccination cards), and inaccurate recording of vaccination on HBRs. We developed an innovative method with which to overcome these biases, enhance the validity of survey results, and estimate true vaccine coverage using nested serological assessments of immune markers. We enrolled children aged 12-23 months in vaccine coverage surveys in Karachi, Pakistan, from January to December 2016. Vaccination history was collected through verbal recall by the caregiver and, when available, by HBR. One-third of survey participants were randomly enrolled for serological testing for anti-measles virus immunoglobulin G antibody. We applied Bayesian latent class models to evaluate the misalignment among measles vaccination histories derived by recall, HBRs, and measles serology and estimated true measles vaccine coverage. The model-based estimate of true measles vaccine coverage was 61.1% (95% credible interval: 53.5, 69.4) among all survey participants. The standard estimate of 73.2% (95% confidence interval: 71.3, 75.1) defined by positive recall or HBR documentation substantially overestimated the vaccine coverage. Researchers can correct for information biases using serological assessments in a subsample of survey participants and latent class analytical approaches.

Development and Validation of Parental Vaccine Attitudes Scale for Use in Low-income Setting.

This study aimed to develop a tool and assess its validity to measure childhood vaccine related attitudes among parents in a low-income setting. We developed a vaccine attitudes scale (VAS) composed of 14 Likert items each with 5 responses ranging from strongly agree to strongly disagree (sum of scores range 14-70). The tool was administered to 901 parents with children 4-12 months of age during a vaccine coverage survey in Sindh, Pakistan. We performed factor analysis with eigenvalues >0.3 for sufficient factor loading and calculated Cronbach alpha for reliability. The mean ± SD score on VAS was 48 ± 3 and Cronbach alpha was 0.61. Factor analysis identified that VAS measured 2 different domains related to the childhood vaccine related attitudes; (1) 10 items related to vaccine perceptions and concerns (mean 40 ± 5.5; Cronbach alpha 0.95) and (2) 4 items related to vaccine preventable disease salience and community benefit (mean 7 ± 3; Cronbach alpha 0.97). The odds of children being unimmunized was 5 times higher among parents who scored high (13-20) as compared with low (<13) on the subscale related to disease salience and community benefit (odds ratio 5.2; 95% CI: 3.6-7.6). The odds of children being unimmunized was 1.5 times higher among parents scoring high (40-50) as compared with low (<40) on subscale related to vaccine perception/concerns (odds ratio 1.5; 95% CI: 1.1-2.2). The 4-item scale assessing parental attitudes toward vaccine preventable disease salience and community benefit is sufficiently reliable and can predict vaccine acceptance among parents in low income setting.

Home-based records’ quality and validity of caregivers’ recall of children’s vaccination in Lebanon

IntroductionHome-based records (HBRs) (also known as vaccination cards) and caregivers’ recall are the main means to ascertain vaccination status; however, data on the quality of HBRs and the validity of recall vaccination data compared to HBRs is scarce. This manuscript presents results from two analyses related to HBRs, one on HBR pictures taken during a vaccination coverage survey, including an assessment of the HBR quality and legibility, and an evaluation of the agreement between caregivers’ recall and the vaccination information in the HBRs. MethodsUsing pictures from 500 randomly selected HBRs collected during the 2016 district-based immunization coverage evaluation survey in Lebanon, two independent researchers assessed the quality of the picture and then of the HBR itself against a pre-defined set of criteria. HBRs were classified into three types: private, public and all others. In addition, caregivers’ recall was compared to data found in vaccination HBRs to assess measures of vaccination status agreement for 5713 children for whom both sources of data were available. ResultsOver 90% of the 500 HBR pictures reviewed were considered adequate to assess the HBR quality. In the sample, most cards were type 1 (41%), followed by type 2 (34%). Most HBRs met the set criteria for quality in terms of physical condition and legibility, while, among the 28 different types of cards, vaccination cards’ content and design met a moderate level of quality. Concordance, sensitivity, specificity, positive and negative predictive values, and the Kappa statistic showed diverse levels of agreement for vaccination status per vaccine dose between caregivers’ recall and vaccination HBRs. ConclusionThis study illustrates that taking pictures of HBRs in a coverage survey is feasible and useful to conduct secondary analyses related to HBRs, such as assessing their quality and comparing recall with HBRs when both sources of data are available.

Measles and rubella serosurvey identifies rubella immunity gap in young adults of childbearing age in Zambia: The added value of nesting a serological survey within a post-campaign coverage evaluation survey

BackgroundSerological surveys can potentially complement vaccine coverage surveys, such as post-vaccination campaign coverage evaluation surveys (PCES), by providing direct information on population immunity within and outside the target age range of the mass vaccination campaign. We estimate age-specific population immunity to measles and rubella viruses in Southern Province, Zambia, and assess the value of adding serological data to vaccination coverage estimates by nesting a serological survey within a PCES. MethodsDried blood spots (DBS) from fingerprick blood were collected from all individuals ages nine months or older in households participating in the PCES and tested for measles and rubella virus-specific immunoglobulin G (IgG) by enzyme immunoassay (Siemens Enzygnost, Marburg, Germany). ResultsOverall seroprevalence was 95.5% (95% CI: 92.8, 97.2) for measles virus-specific IgG and 97.7% (95% CI: 96.0, 98.7) for rubella virus-specific IgG. Rubella seroprevalence was 98.4% (95% CI: 95.9, 99.4) among children eligible for the MR vaccination campaign, significantly higher than the reported measles-rubella (MR) vaccination campaign coverage of 89.8% (p = 0.003), and higher than the 91.3% rubella seroprevalence for adolescents and adults 16–30 years of age (p = 0.049). ConclusionSeroprevalence to measles and rubella viruses in children younger than 16 years of age was significantly higher than expected from vaccination coverage estimates, likely reflecting exposure to wild-type viruses and underreporting of vaccination. The serosurvey revealed rubella immunity gaps among women 16–30 years of age, precisely the age group in which protection from rubella is most important to prevent congenital rubella syndrome. Nesting serological surveys within existing surveys can leverage resources and infrastructure while providing complementary information important to immunization programs.

ASSESSMENT OF RISK FACTORS AND DETERMINATION OF VACCINE EFFICACY FOR MEASLES OUTBREAK DURING APRIL 2017 IN DHOK KAZIN, ISLAMABAD

Background: On 13th April 2017, 3 measles cases were reported in Dhok Kazin, Islamabad to National Institute of Health, Islamabad. Federal Disease Surveillance &amp; Response Unit on request of Islamabad Capital Territory (ICT) health administration started disease outbreak investigation and active case finding. The study was aimed to identify risk factors associated with disease outbreak, to assess vaccine coverage and vaccine efficacy in the outbreak area, and to suggest control measures. Methods: To determine possible risk factors age and sex matched case-control study was conducted in April, 2017. A case was defined as "Any resident of Dhok Kazin, presented with fever and maculopapular rash with any of signs/symptoms like coryza, conjunctivitis, cough, otitis media or pneumonia after March 20 to April 30, 2017". For each case 04 matched controls were selected. A structured questionnaire prepared to collect data. Vaccine coverage survey was conducted. Uni and multivariate analyses and vaccine efficacy were calculated. Results: A total of 14 cases identified including 11 cases found on active search. Cases were compared with 57 matched controls. Mean age was 39 months (range 08- 132 months). Among cases male to female ratio observed was 1:2.5. Overall attack rate was 1.2%, while most severely affected age-group was &lt;12 months (AR=10.3%). The most common complications were diarrhea n=8 (57.1%) and pneumonia n=1 (7.1%). On vaccine coverage survey in 230 households, 31(70.5%) out of 44 children checked were vaccinated. The un-vaccinated children had attack rate of 14.3% while vaccinated had attack rate of 6.7%. The vaccine efficacy calculated was 53%. Significant association found in risk factors were; contact with positive case [OR 19.5, 95% CI; 4.5-84, P=0.00], unvaccinated children [OR=10.0, 95%, CI;1.2.0-49.3, P= 0.003], Mother illiteracy [OR 10.2, 95% CI; 2.5-41, P=0.00], Misconception about vaccination [OR 13.2, 95%, CI;3.1-57.1, P=0.00), vaccinator not visited home as a part of outreach activity [OR=6.4, 95%CI;1.7-23.4, P=0.00]. Reasons for non-vaccination were found to be misconception about vaccination (OR=34.8, 95%CI=5.5-219.7) and mother's illiteracy (OR=6.4, 95%CI=1.2-34.8). Conclusion: Most severely affected age group was 12 months and below. Low immunization rates were the most probable cause of outbreak. Case contacts, partial vaccination, misconception of vaccination, no visit of vaccinator to home, and mother's education were risk factors significantly associated with Measles outbreak. Findings were shared with the district health authorities for implementation of control measures.