Third Dose Of Pentavalent Vaccine Research Articles

Characterizing zero-dose and under-vaccinated children among refugees and internally displaced persons in the Democratic Republic of Congo

BackgroundThe Democratic Republic of Congo (DRC) has one of the highest numbers of un and under-vaccinated children as well as number of refugees and internally displaced persons (IDPs) in the world. This study aims to determine and compare the proportion and characteristics of zero-dose (ZD) and under-vaccinated (UV) children among refugees and IDPs in the DRC, as well as the reasons for incomplete vaccination schedules.MethodsData from a rolling vaccination coverage survey conducted from September 10, 2022, to July 03, 2023, among refugees and IDPs in 12 provinces of the DRC. ZD was defined as a child aged 12–23 months who had not received any dose of pentavalent vaccine DTP-Hib-Hep B (by card or recall) and UV as a child who had not received the third dose of pentavalent vaccine. The proportions of non and under-vaccination and the associated factors using a logistic regression model are presented for ZD and UV children. The reasons for non-vaccination of these children are described using the WHO-Immunization behavioral and social-drivers-conceptual framework and compared using Pearson’s Chi2 test.ResultsOf 692 children aged 12 to 23 months included in the analysis, 9.3% (95% CI: 7.2–11.7%) were ZD and 40.9% (95% CI: 95%: 37.2–44.6%) UV. The Penta1/Penta3 drop-out rate was 34.9%. After adjustment, ZD children had a significant history of home or road birth. And UV children were significantly associated with mothers/caregivers being under 40, uneducated, farmers, ranchers, employed, rural residents, as well as with home or road births. Reasons linked to people’s perceptions and feelings were cited much more often for ZD (50.0%) than for UV (38.3%). Those related to social reasons were cited much more often by ZD (40.6%) than by UV (35.7%). Reasons related to “programmatic and practical issues” were cited less for ZD (90.5%) than for UV (97.1%).ConclusionsZD and UV children represent significant proportions in refugee and IDPs sites in the DRC. However, the proportion of ZD is less than for the entire country, while the proportion of UV is comparable, reflected in a very high drop-out rate. Similarly to studies in the general population in DRC, the reasons for ZD children were mainly linked to challenges in caregiver motivation to vaccinate, while for UV children, they were more often linked to pro-grammatic and practical problems of the health system.

The status of immunization program and challenges in Ethiopia: A mixed method study.

Immunization helps reduce morbidity and mortality attributable to severe vaccine-preventable childhood illnesses. However, vaccination coverage and the quality of immunization data remain challenging in Ethiopia. This has led to poor planning, suboptimal vaccination coverage, and the resurgence of vaccine-preventable disease outbreaks in under-immunized pocket areas. The problem is further compounded by the occurrence of the COVID-19 pandemic and the disruption of the health information system due to recurrent conflict. This study assessed the current status of the immunization service and its challenges in Ethiopia. A mixed-methods study was conducted in three regions of Ethiopia from 21 to 31 May, 2023. A survey of administrative reports was done in a total of 69 health facilities in 14 woredas (districts). Nine KIIs were conducted at a district level among immunization coordinators selected from three regions to explore the challenges of the immunization program. Linear regression and descriptive statistics were used to analyze the quantitative data. Thematic analysis was applied to analyze the qualitative data. The findings from the qualitative data were triangulated to supplement the quantitative results. Two-thirds (66.4%) of the children were fully vaccinated, having received all vaccines, including the first dose of the MCV1, by 12 months of age, as reported through administrative reports collected from health facility records. Catchment area population size and region were significantly associated with the number of fully immunized children (p < 0.001 and p = 0.005, respectively). The vaccination dropout rates of the first to third dose of pentavalent vaccine and the first dose of pentavalent vaccine to the first dose of MCV1 were 8.6% and 7.4%, respectively. A considerable proportion of health facilities lack accurate data to calculate vaccination coverage, while most of them lack accurate data for dropout rates. Longer waiting time, interruptions in vaccine supply or shortage, inaccessibility of health facilities, internal conflict and displacement, power interruption and refrigerator breakdown, poor counseling practice, and caretakers' lack of awareness, fear of side effects, and forgetfulness were the reasons for the dropout rate and low coverage. The result also showed that internal conflict and displacement have significantly affected immunization coverage, with the worst effects seen on the most marginalized populations. The study revealed low vaccination coverage, a high dropout rate, and poor quality of immunization data. Access and vaccination coverage among marginalized community groups (e.g., orphans and street children) were also low. Hence, interventions to address organizational, behavioral, technical, and contextual (conflict and the resulting internal displacement) bottlenecks affecting the immunization program should be addressed.

Impact of hepatitis B birth dose on immune response in Pakistani children: an open-label, non-inferiority randomized controlled trial, implications for achieving SDG target

Background Despite presence of hyperendemic areas, the national immunisation schedule in Pakistan does not include a hepatitis B birth dose, placing newborns at an additional risk of acquiring hepatitis B. This study aimed to assess the impact of adding hepatitis B birth dose in existing national vaccination schedule. Methods An open label, randomised controlled non-inferiority trial enrolled 296 healthy near-term mothers to intervention and control groups. Newborns in the intervention group received a hepatitis B birth dose along with routine immunisation vaccines, while control group newborns received vaccinations under the national schedule. Seroprotection was measured and compared at birth and 8 weeks after administering the third dose of pentavalent vaccine. The risk ratio of seroprotection was computed and compared with the delta value set at 5%. Results The study found that 95.8% of infants in the intervention group achieved seroprotection, which was significantly higher than the control group’s 58.7%. The difference in risk ratio of seroprotection was 1.62 (CI95: 1.37–1.93), with the upper limit of the CI below the delta margin, confirming non-inferiority. The time interval between birth and the first hepatitis B immunisation shot was a predictor of seroprotection, with an odds ratio of 1.79 (CI95: 1.01–2.9). Conclusion Our study indicates that adding a hepatitis B birth dose to the immunisation schedule in Pakistan is non-inferior to the existing one. This can also contribute towards Pakistan’s achievement of the SDG target of reducing hepatitis B surface antigen seroprevalence in children under 5 years of age. Trial Registration Number NCT04870021

COVID-19 Vaccination: Opportunity to Strengthen Immunization System in Belize

Objective: To describe the process of leveraging COVID-19 vaccination roll out to strengthen immunization system in Belize. Methodology: The Case study was conducted using desk review of relevant documents for the roll out of COVID 19 vaccination in response to the pandemic and analysis of the COVID-19 vaccination and routine immunization data extracted from the Belize Health Information System. The approach was a retrospective review of the strategies adopted by the government of Belize with support of UNICEF and other health partners using the roll out of COVID-19 vaccination to strengthen the country’s immunization system. Descriptive data is presented in graph and table and a test of association was done using a paired t-test to compare the mean change in annual routine immunization coverage before (2020) and after (2022) roll out of COVID-19 vaccination and p-value was set at a significant level of 5% Results: The National Vaccine Implementation Plan for the introduction of COVID-19 vaccination in 2021 was used as a transformative opportunity for building resilient immunization programs. Key areas focused on in the study were the enhancement of cold chain equipment and storage capacity, utilization of digital tools, improved data management, and innovative immunization service delivery. The result shows that the annual coverage of the first dose and third dose of pentavalent vaccine (Penta 3) increased from 79% and 78.5% in 2020 to 91% and 84.3% in 2022 respectively though not statistically significant (p value&gt; 0.05). So far, 258,443 (65% of the total population) have received at least one dose of COVID-19 vaccine and 221,402 individuals (51.3% of the total population) have been fully vaccinated. Conclusion: The study contributes to the existing literature on the use of COVID-19 investments as an opportunity to strengthen the health system with a focus on immunization services which is essential in building a resilient health system.

Factors associated with pentavalent vaccine coverage among 12-23-month-old children in Afghanistan: A cross-sectional study.

This study aimed to identify the factors associated with the coverage of the third dose of pentavalent vaccine (Penta3) among children aged 12-23 months in Afghanistan. The data of 3,040 children aged 12-23 months were taken from the Afghanistan Health Survey 2018, including characteristics of the children and their households, household heads, and mothers/primary care givers. Adjusted odds ratios (AORs) and 95% confidence intervals (CIs) were estimated using a logistic model. Multivariable stepwise logistic regression analysis with forward-selection (Model 1) and backward-selection (Model 2) was performed using variables that showed significant differences by bivariate analysis. The coverage of Penta3 among 12-23-month-old children was 82.3%. Factors associated with Penta3 coverage in the two models of multivariable analysis were 18-23 months old compared to 12-17 months old; having no diarrhea in the last two weeks compared to having diarrhea; no bipedal edema compared to having edema; taking vitamin A supplement; 1-2 children under five years in a household compared to three or more; distance from residence to the nearest health facility ≤2 hours on foot; having a radio; having a TV; educated heads of households; non-smoking of heads of households; and literacy of mothers/primary caregivers. Penta3 coverage among 12-23-month-old children improved but was still lower than the target. Primary education should be provided to all children throughout the country. TV and radio are useful tools for providing health information. Mobile outreach programs and the establishment of new health facilities should be promoted to improve access to health service for all people in Afghanistan.

The impact of the COVID-19 pandemic on vaccine coverage in Kilifi, Kenya: A retrospective cohort study.

The COVID-19 pandemic caused unprecedented disruption in health service delivery, globally. This study sought to provide evidence on the impact of the pandemic on vaccine coverage in Kilifi County, Kenya. We conducted a vaccine coverage survey between April and June 2021 within the Kilifi Health and Demographic Surveillance System (KHDSS). Simple random sampling was used to identify 1500 children aged 6weeks-59months. Participants were grouped into three retrospective cohorts based on when they became age-eligible for vaccination: before the pandemic, during the first year, or during the second year of the pandemic. Survival analysis with Cox regression was used to evaluate the association between the time-period at which participants became age-eligible for vaccination and the rate of vaccination within a month of age-eligibility for the third dose of pentavalent vaccine (Pentavalent-3) and within three months of age-eligibility for the first dose of Measles vaccine (MCV-1). A total of 1,341 participants were included in the survey. Compared to the pre-COVID-19 baseline period, the rate of vaccination within a month of age-eligibility for Pentavalent-3 was not significantly different in the first year of the pandemic (adjusted hazard ratio [aHR] 1.03, 95% confidence interval [CI] 0.90-1.18) and was significantly higher during the second year of the pandemic (aHR 1.33, 95% CI 1.07-1.65). The rate of vaccination with MCV-1 within three months of age-eligibility was not significantly different among those age-eligible for vaccination during the first year of the pandemic (aHR 1.04, 95% CI 0.88-1.21) and was 35% higher during the second year of the pandemic (95% CI 1.11-1.64), compared to those age-eligible pre-COVID-19. After adjusting for known determinants of vaccination, the COVID-19 pandemic did not adversely affect the rate of vaccination within the KHDSS.

Use of catch-up vaccinations in the second year of life (2YL) platform to close immunity gaps: A secondary DHS analysis in Pakistan, Philippines, and South Africa

BackgroundImmunity gaps caused by COVID-19-related disruptions highlight the importance of catch-up vaccination. Number of countries offering vaccines in second year of life (2YL) has increased, but use of 2YL for catch-up vaccination has been variable. We assessed pre-pandemic use of 2YL for catch-up vaccination in three countries (Pakistan, the Philippines, and South Africa), based on existence of a 2YL platform (demonstrated by offering second dose of measles-containing vaccine (MCV2) in 2YL), proportion of card availability, and geographical variety. MethodsWe conducted a secondary data analysis of immunization data from Demographic and Health Surveys (DHS) in Pakistan (2017–2018), the Philippines (2017), and South Africa (2016). We conducted time-to-event analyses for pentavalent vaccine (diphtheria-tetanus-pertussis-Hepatitis B-Haemophilus influenzae type b [Hib]) and MCV and calculated use of 2YL and MCV visits for catch-up vaccination. ResultsAmong 24–35-month-olds with documented dates, coverage of third dose of pentavalent vaccine increased in 2YL by 2%, 3%, and 1% in Pakistan, Philippines, and South Africa, respectively. MCV1 coverage increased in 2YL by 5% in Pakistan, 10% in the Philippines, and 3% in South Africa. In Pakistan, among 124 children eligible for catch-up vaccination of pentavalent vaccine at time of a documented MCV visit, 45% received a catch-up dose. In the Philippines, among 381 eligible children, 38% received a pentavalent dose during an MCV visit. In South Africa, 50 children were eligible for a pentavalent vaccine dose before their MCV1 visit, but only 20% received it; none with MCV2. ConclusionSmall to modest vaccine coverage improvements occurred in all three countries through catch-up vaccination in 2YL but many missed opportunities for vaccination continue to occur. Using the 2YL platform can increase coverage and close immunity gaps, but immunization programmes need to change policies, practices, and monitor catch-up vaccination to maximize the potential.

Pentavalent vaccination in Kenya: coverage and geographical accessibility to health facilities using data from a community demographic and health surveillance system in Kilifi County

BackgroundThere is substantial evidence that immunization is one of the most significant and cost-effective pillars of preventive and promotive health interventions. Effective childhood immunization coverage is thus essential in stemming persistent childhood illnesses. The third dose of pentavalent vaccine for children is an important indicator for assessing performance of the immunisation programme because it mirrors the completeness of a child’s immunisation schedule. Spatial access to an immunizing health facility, especially in sub-Sahara African (SSA) countries, is a significant determinant of Pentavalent 3 vaccination coverage, as the vaccine is mainly administered during routine immunisation schedules at health facilities. Rural areas and densely populated informal settlements are most affected by poor access to healthcare services. We therefore sought to determine vaccination coverage of Pentavalent 3, estimate the travel time to health facilities offering immunisation services, and explore its effect on immunisation coverage in one of the predominantly rural counties on the coast of Kenya.MethodsWe used longitudinal survey data from the health demographic surveillance system implemented in Kaloleni and Rabai Sub-counties in Kenya. To compute the geographical accessibility, we used coordinates of health facilities offering immunisation services, information on land cover, digital elevation models, and road networks of the study area. We then fitted a hierarchical Bayesian multivariable model to explore the effect of travel time on pentavalent vaccine coverage adjusting for confounding factors identified a priori.ResultsOverall coverage of pentavalent vaccine was at 77.3%. The median travel time to a health facility was 41 min (IQR = 18–65) and a total of 1266 (28.5%) children lived more than one-hour of travel-time to a health facility. Geographical access to health facilities significantly affected pentavalent vaccination coverage, with travel times of more than one hour being significantly associated with reduced odds of vaccination (AOR = 0.84 (95% CI 0.74 – 0.94).ConclusionIncreased travel time significantly affects immunization in this rural community. Improving road networks, establishing new health centres and/or stepping up health outreach activities that include vaccinations in hard-to-reach areas within the county could improve immunisation coverage. These data may be useful in guiding the local department of health on appropriate location of planned immunization centres.

Determinants of pentavalent and measles vaccination dropouts among children aged 12\u201323 months in The Gambia

BackgroundEvery year, vaccination averts about 3 million deaths from vaccine-preventable diseases (VPDs). However, despite that immunization coverage is increasing globally, many children in developing countries are still dropping out of vaccination. Thus, the present study aimed to identify determinants of vaccination dropouts among children aged 12–23 months in The Gambia.MethodsThe study utilized cross-sectional data obtained from the Gambia Demographic and Health Survey 2019–20 (GDHS). The percentage of children aged 12–23 months who dropped out from pentavalent and measles vaccination were calculated by (1) subtracting the third dose of pentavalent vaccine from the first dose of Pentavalent vaccine, and (2) subtracting the first dose of measles vaccine from the first dose Pentavalent vaccine. Generalized Estimating Equation models (GEE) were constructed to examine the risk factors of pentavalent and measles vaccinations dropout.ResultsApproximately 7.0% and 4.0% of the 1,302 children aged 12–23 months had dropped out of measles and pentavalent vaccination respectively. The multivariate analyses showed that when caregivers attended fewer than four antenatal care sessions, when children had no health card or whose card was lost, and resided in urban areas increased the odds of pentavalent dropout. On the other hand, when women gave birth in home and other places, when children had no health card, and being an urban areas dweller increased the odds of measles dropout.ConclusionTailored public health interventions towards urban residence and health education for all women during ANC are hereby recommended.

Timeliness of Vaccination among Children Attending Immunization Clinic at a Tertiary Hospital in South-East Nigeria.

Timely vaccination of children is one of the most cost-effective interventions that ensure childhood survival. We determined the proportion of children who received timely vaccination and examined the factors associated with timely receipt of Bacillus Calmette Guerin (BCG) and third dose of pentavalent vaccine (Penta 3). We conducted a cross-sectional survey among 599 caregivers-infant pair aged less than 24months, attending the immunization clinic of a tertiary hospital in Nigeria, selected using systematic sampling methods. Using a structured questionnaire, we access the proportion of children who received timely vaccination, the relationship between the timely receipt of BCG, Penta 3 vaccine and infant/caregiver characteristics was examined using chi-square and multiple logistic regression at a 5% level of significance. The mean age of the respondents was 30.1±5.0 years. The majority (73.8%) had attained tertiary education, lived in an urban setting (90.9%), had received antenatal care during pregnancy (99.3%) and was delivered in a hospital (97.0%). About half of the children (52.9%) were male. About 18% of the caregivers reported missing scheduled immunization visits, due to forgetfulness (18%), child illness (14%) and being busy (5%). About 88% (482) of the children got their BCG vaccines on time, 91.1% got timely OPV0, however, only 29.5% of the newborns got HBV0 within 24 hours of birth. Only 65.7% and 65.0% received the timely measles-containing vaccine and yellow fever vaccine. None of the factors examined predicted timely receipt of BCG and Penta 3 vaccines. Interventions that remind caregivers about the immunization schedules, could improve timely vaccination.

Assessment of Factors Associated with Dropout for Pentavalent Vaccine in Tertiary Care Hospital of Kathmandu, Nepal

Immunization is one of the most cost-effective public health measures as it has helped in huge reduction of disease, disability and death from different infectious diseases in children by protecting them from vaccine preventable diseases. The current study aimed to study factors associated with dropout for pentavalent vaccine in tertiary care hospital of Kathmandu. A longitudinal observational study using purposive sampling technique was conducted among 196 infants. The information was obtained using self-constructed structured questionnaire from parents visiting Community Medicine OPD of Nepal Medical College Teaching Hospital. The information regarding socioeconomic characteristics of mother, gender of the infant, place of delivery of child, birth order and reasons for dropout of pentavalent third dose were taken. The dropout of third dose pentavalent vaccine was mainly seen in infant of parents living in rented house and according to gender wise, dropout was high among male infants. The different reasons for dropout of vaccine were busy parents, forgotten date, visit to other immunization centres and sick infants. Among these, the main reason for dropout of vaccine was due to infants getting sick during the time of immunization. The dropout rates between first and third dose of pentavalent vaccine were 26.3% and 30.4% respectively for two consecutive months and the overall dropout rate was 28.35%. Also, literacy level of the mother was directly associated with the immunization visit of the infant as, maximum number of infants of illiterate mother were absent for third dose of pentavalent vaccine as opposed to no absentee among master degree holding mothers. Thus, the present study provides valuable information regarding the factors associated with dropout for pentavalent vaccine.

Data on the implementation of VaxTrac electronic immunization registry in Sierra Leone.

Following the piloting of VaxTrac, an electronic immunization registry (EIR), we conducted a rapid assessment in November-December 2017 to evaluate the use of the EIR in 10 health facilities in Western Area Urban district in Sierra Leone [1]. In this data-in-brief report, we provide additional descriptive data from the assessment of the VaxTrac EIR in Sierra Leone. The assessment comprised aggregate data on vaccine doses administered that were abstracted from VaxTrac and three paper-based sources (daily tally sheets, register of children under the age of 2 years, and a summary form of doses administered). Data were abstracted for the following six vaccine doses in the immunization schedule in Sierra Leone: 1) Bacillus Calmette–Guérin vaccine, 2) first dose of pentavalent vaccine, 3) second dose of pentavalent vaccine, 4) third dose of pentavalent vaccine, 5) first dose of measles-containing vaccine, and 6) second dose of measles-containing vaccine. We descriptively analysed the abstracted data to examine the congruity between VaxTrac records and the three paper-based sources. Bar graphs were generated to visually depict the variations in number of administered vaccine doses by data source for each health facility. We provide the aggregated data for each vaccine dose abstracted by data source from each health facility as supplemental material (Excel file). The supplementary data reveal patterns in the congruity of vaccine doses captured that have implications for policy and programmatic decisions regarding the use of VaxTrac and other similar EIRs in low resource urban settings.

Data quality self-assessment of child health and sexual reproductive health indicators in Botswana, 2016-2017.

There is no published data on quality of administrative data for various health indicators in Botswana, yet such data are used for policy making and future planning. This article reports on quality of data on child health and sexual and reproductive health (SRH) indicators in Botswana. The main objective of the study was to assess the quality of administrative data from Expanded Immunization Program (EPI) and condom use, Depo-Provera uptake and domiciliary care attendance in Botswana. This was a retrospective study entailing a review of data retrieved from district health records and District Health Information System (DHIS). A total of 30 clinics and health posts were randomly selected from two cities, a town and three rural villages which makes up 6 districts commonly denoted urban, semi-urban and rural respectively. Through a stratified random sampling health facilities were selected. EPI data (Penta 3- third dose of pentavalent vaccine and Measles vaccine) and SRH data (condom use, Depo-Provera uptake and Domiciliary care) were assessed for completeness, discrepancies and verification factor using WHO Routine data quality (RDQA) assessment tool. A verification score of less than 90%% was considered as underreporting while more than 110% is over reporting. However, the score which is within +-10% is acceptable, reliable and a good indicator of data quality and reporting system. About 56% (9/16) SRH indicators had a verification factor score outside the accepted range and 87% (13/15) discrepancy value outside the accepted range. For immunization, 10% (1/10) had a verification factor score outside the accepted range and 33% (3/9) had a discrepancy value outside the accepted range. The level of completeness was high for both Penta3 and Measles coverage and it was lowest for condom. Our findings highlight a poorer data quality for SRH indicators compared to child health indicators. A comprehensive program review drawing lessons from the child health indicators is required to improve the quality of administrative data in Botswana.

Oropharyngeal Colonization of Haemophilus influenzae Type b and Serologic Response After Administration of Third Dose of Pentavalent Vaccine to 12-Month-Old Children in Karaj, Iran, 2016

Background: The administration of Haemophilus influenzae type b (Hib) conjugate vaccine led to a decrease of over 90% in the prevalence of severe Hib diseases in the countries with universal coverage vaccine. After addition of Hib vaccine to the national vaccination program and since no study has yet investigated this subject. Objectives: The current study aimed at investigating the serologic response and assessing oropharyngeal colonization with Hib after the last dose of vaccine. Methods: A total of 500 blood and oropharyngeal samples were collected from one-year-old children referred to Karaj health care centers, Iran. Demographic information and risk factors of the children were collected. Oropharyngeal and blood samples were transferred to the laboratory to determine antibody titer by the enzyme-linked immunosorbent assay (ELISA) technique, culture testing, and polymerase chain reaction (PCR). Results: In the current study, 11.8% of children (95% confidence interval (CI): 8.97 - 14.63) had an anti-Hib IgG titer of ≥ 5 µg/mL. Geometric mean titer (GMT) of vaccine antibody was 6.92 µg/mL (95% CI: 6.76 - 7.08); 9% of oropharyngeal culture results were positive for H. influaenzae (non-type b) and 8.2% were confirmed by PCR. Prevalence of oropheryngeal Hib colonization was 0.02%. There was no significant correlation between the titer of H. influaenzae antibody and positive culture of H. influaenzae and the other studied variables (P > 0.05). Conclusions: In Iran, similar to most countries, pentavalent vaccine in national vaccination program decreased the prevalence of Hib colonization. Prevalence of Hib colonization is an important factor in invasive diseases incidence. It is suggested that further studies asses the prevalence of invasive Hib diseases after national vaccination.

Oropharyngeal Colonization of Haemophilus influenzae Type b and Serologic Response After Administration of Third Dose of Pentavalent Vaccine to 12-Month-Old Children in Karaj, Iran, 2016

Background: The administration of Haemophilus influenzae type b (Hib) conjugate vaccine led to a decrease of over 90% in the prevalence of severe Hib diseases in the countries with universal coverage vaccine. After addition of Hib vaccine to the national vaccination program and since no study has yet investigated this subject. Objectives: The current study aimed at investigating the serologic response and assessing oropharyngeal colonization with Hib after the last dose of vaccine. Methods: A total of 500 blood and oropharyngeal samples were collected from one-year-old children referred to Karaj health care centers, Iran. Demographic information and risk factors of the children were collected. Oropharyngeal and blood samples were transferred to the laboratory to determine antibody titer by the enzyme-linked immunosorbent assay (ELISA) technique, culture testing, and polymerase chain reaction (PCR). Results: In the current study, 11.8% of children (95% confidence interval (CI): 8.97 - 14.63) had an anti-Hib IgG titer of ≥ 5 µg/mL. Geometric mean titer (GMT) of vaccine antibody was 6.92 µg/mL (95% CI: 6.76 - 7.08); 9% of oropharyngeal culture results were positive for H. influaenzae (non-type b) and 8.2% were confirmed by PCR. Prevalence of oropheryngeal Hib colonization was 0.02%. There was no significant correlation between the titer of H. influaenzae antibody and positive culture of H. influaenzae and the other studied variables (P > 0.05). Conclusions: In Iran, similar to most countries, pentavalent vaccine in national vaccination program decreased the prevalence of Hib colonization. Prevalence of Hib colonization is an important factor in invasive diseases incidence. It is suggested that further studies asses the prevalence of invasive Hib diseases after national vaccination.

Comparison of Micro-Census Results for Magarya Ward, Wurno Local Government Area of Sokoto State, Nigeria, with Other Sources of Denominator Data.

Routine immunization coverage in Nigeria is suboptimal. In the northwestern state of Sokoto, an independent population-based survey for 2016 found immunization coverage with the third dose of Pentavalent vaccine to be 3%, whereas administrative coverage in 2016 was reported to be 69%. One possibility driving this large discrepancy is that administrative coverage is calculated using an under-estimated target population. Official population projections from the 2006 Census are based on state-specific standard population growth rates. Immunization target population estimates from other sources have not been independently validated. We conducted a micro-census in Magarya ward, Wurno Local Government Area of Sokoto state to obtain an accurate count of the total population living in the ward, and to compare these results with other sources of denominator data. We developed a precise micro-plan using satellite imagery, and used the navigation tool EpiSample v1 in the field to guide teams to each building, without duplications or omissions. The particular characteristics of the selected ward underscore the importance of using standardized shape files to draw precise boundaries for enumeration micro-plans. While the use of this methodology did not resolve the discrepancy between independent and administrative vaccination coverage rates, a simplified application can better define the target population for routine immunization services and estimate the number of children still unprotected from vaccine-preventable diseases.

Study of Serologic Response Rate to Haemophilus influenzae Type B After Administration of the Third Dose of Pentavalent Vaccine in Children Aged 12 Months in Karaj City in 2016

Background: Hib conjugate vaccine has led to more than 90% decline in the prevalence of severe Hib diseases in countries with universal coverage vaccination program. After the addition of Hib vaccine to the national vaccination program with 3P (three doses of 2, 4, and 6 months) in IR Iran, we decided to study the vaccine efficacy after the last dose of vaccine in Iranian children in 2016. Methods: 500 blood samples were collected from one-year-old children who referred to the health care centers in Karaj. Demographic information was gathered by a questionnaire. Blood samples were sent to a laboratory for antibody titer determination by ELISA method. Results: 41.2% of the children (95% CI: 36.89 - 45.51) had a titre of IgG against Hib (0.15 to 1 µg/mL) (short-term protection) and 57.4% of the children had a titre of IgG against Hib (95% CI: 53.07 - 61.73) equal to or greater than 1 µg/mL (long-term protection). Antibody GMT was 6.92 µg/mL (95% CI: 6.76 - 7.08). There was no significant correlation between the titer of H. influaenza antibody and demographic factors. Conclusions: In spite of the acceptable GMT titer, children who had antibody titer of < 1 µg/mL comprised approximately 40% of the study population, showing the necessity of further investigation to assess the need for H.flu booster administration.

Anti-HBs Titers Following Pentavalent Immunization (DTwP-HBV-Hib) in Term Normal Weight vs Low Birthweight Infants

To compare anti-HBs titers between term low birth weight (1800-2499 g) infants and normal birthweight infants, 6 weeks after last dose of primary immunization with pentavalent vaccine, and to study adverse events following immunization (AEFI) with pentavalent vaccine. Cohort study. Tertiary-care hospital predominantly catering to urban poor population of East Delhi. 265 low birthweight (1800-2499 g) and 265 normal birthweight (2500-4000 g) infants. Monovalent Hepatitis B vaccine was administered within 24 hours of birth followed by three primary doses of pentavalent vaccine at 6, 10 and 14 weeks. Anti-HBs titers were estimated after 6 weeks of third dose of pentavalent vaccine. Adverse events following immunization (AEFI) month were observed for a month after each dose of pentavalent vaccine. Anti HBs antibody titers after 6 weeks of primary immunization, and AEFI. 443 (83.5%) infants (225 low birthweight and 218 normal birthweight infants) completed the follow-up. Seroprotection against hepatitis B virus was achieved in both groups after pentavalent vaccine administration. Anti HBs GMTs in low birthweight infants (194.8 mIU/mL) and normal birthweight infants (204.2 mIU/mL) were comparable (P = 0.17). No serious adverse events were observed in either group. Three primary doses of pentavalent vaccine administered along with zero dose of Hepatitis B vaccine at birth provide good seroprotection. The vaccine appears to be safe in both low birth weight and normal birthweight infants born at term.

Study of Serologic Response Rate to Pertussis after Administration of the Third Dose of Pentavalent Vaccine in Children 12 Months Old in Karaj City, Iran

Background: After substitution of Pentavalent vaccine with diphtheria, tetanus, pertussis (DTP) in the Iranian National Vaccination program with 3 Pentavalent (three times vaccination with Pentavalent vaccine at months 2, 4, and 6) in 2014 and the lack of published research in the field of immunogenicity of pertussis component of this vaccine, the efficacy of pertussis vaccine was studied 6 months after the last dose of Pentavalent vaccine in Iranian infants. Materials and Methods: Five hundred blood samples were collected from healthy one-year-old children who attended 18 health care centers of Karaj, Iran for routine vaccination selected by cluster sampling (2016). Sampling checklists contained demographic information and risk factors. The blood samples were sent to the laboratory for determination of Immunoglobulin G (IgG) and IgA anti-pertussis antibody titer by ELISA method. Data were analyzed by STATA software (version 14.0). Results: 82.7% (n=413) of children (95% confidence interval [CI]: 79.49-86.11) had IgG titer less than 16 IU/ml against pertussis (no immune response), and 17.3% (n=87) had equal or greater than 16 IU/ml IgG titer against pertussis (95% CI: 13.89-20.51). IgA titer against pertussis was less than 8U/ml in all cases. Anti-pertussis IgG geometric mean titer (GMT) was 15.80 U/ml (95% CI: 15.26-16.36), and IgA GMT was 6.26 U/ml (95% CI: 6.22-6.30). There was not a significant correlation between titer of pertussis antibody and demographic factors. Conclusion: Based on low IgG titer in vaccinated children, immunogenicity of pentavalent vaccine in Iranian children needs more investigation. In this study, 100 % of children had negative serologic response (IgA

Determinants of complete immunization among senegalese children aged 12\u201323\xa0months: evidence from the demographic and health survey

BackgroundThe expanded Programme on Immunization (EPI) is one of the most cost-effective interventions to reduce childhood mortality and morbidity. However, determinants of childhood immunization have not been well studied in Senegal. Thus, the aim of our study is to assess routine immunization uptake and factors associated with full immunization status among Senegalese children aged 12–23 months.MethodsWe used the 2010–2011 Senegalese Demographic and Health Survey data. The DHS was a two stages cross-sectional survey carried out in 2010–2011. The analysis included 2199 children aged 12–23 months. The interviewers collected information on vaccine uptake based on information from vaccination cards or maternal recall Univariate and multivariable logistic regressions models were used to identify the determinants of full childhood immunization.ResultsThe prevalence of complete immunization coverage among boys and girls based on both vaccination card information and mothers’ recall was 62.8%. The immunization coverage as documented on vaccination cards was 37.5%. Specific coverage for the single dose of BCG at birth, the third dose of polio vaccine, the third dose of pentavalent vaccine and the first dose of measles vaccine were 94.7%, 72.7%, 82.6%, and 82.1%, respectively. We found that mothers who could show a vaccination card [AOR 7.27 95% CI (5.50–9.60)], attended at least secondary education level [AOR 1.8 95% CI (1.20–2.48)], attended four antenatal visits [AOR 3.10 95% CI (1.69–5.63)], or delivered at a health facility [AOR 1.27 95% CI (1–1.74)] were the predictors of full childhood immunization. Additionally, children living in the eastern administrative regions of the country were less likely to be fully vaccinated [AOR 0.62 95% CI (0.39–0.97)].ConclusionsWe found that the full immunization coverage among children aged between 12 and 23 months was below the national (> 80%) and international targets (90%). Geographic area, mother’s characteristics, antenatal care and access to health care services were associated with full immunization. These findings highlight the need for innovative strategies based on a holistic approach to overcome the barriers to childhood immunization in Senegal.