Zero Dose Research Articles

Catching-Up in Islamabad, Pakistan: Identifying and Reaching Zero-Dose Children Following the COVID-19

Abstract Background Routine Immunisation (RI) is critical in mitigating child morbidity and mortality while preventing the spread of infectious diseases. Nevertheless, the COVID-19 pandemic has resulted in considerable disruptions, which have given rise to an unprecedented number of zero-dose (ZD) infants. It has presented formidable obstacles for healthcare systems on an international scale. Methods The study employed a retrospective analysis of data obtained from thirteen Supplementary Immunisation Activities (SIAs) that were carried out from 2019 to 2021 to investigate the fluctuations in the documented number of children with ZD. Health authority stakeholder interviews yielded valuable insights about vaccination strategies and obstacles. Results An enormous increase in the number of documented ZD minors were identified during the study period. The number of documented ZD minors rose from 3,827 in 2019 to 4,271 in 2020, and then again to 9,620 in 2021. Notwithstanding diligent attempts to immunise ZD children, the vaccination rate persisted at a less-than-ideal 81.24% of documented ZD children in 2021. Conclusions As a result of the COVID-19 pandemic, pre-existing obstacles to accessing ZD infants in Islamabad were further intensified. The lessons learned emphasise the significance of community engagement, improved outreach strategies, and fortified healthcare infrastructure in guaranteeing comprehensive immunisation coverage. It is imperative to confront these challenges to reduce the likelihood of subsequent epidemics and protect children’s health. Key messages • The spread of COVID-19 among ZD neonates in Islamabad accelerated, prompting calls for improved vaccination programmes. • The suboptimal ZD vaccination rate in 2021, despite concerted efforts, underscores the criticality for enhanced strategies.

Identifying the zero-dose and under-immunized children in Bangladesh: Approaches and experiences.

This paper presents and elaborates on empirical methods and approaches used to identify Zero-Dose (ZD) and Under-immunized (UI) children as well as the communities that these children reside in within Bangladesh. This paper also describes demand- and supply side-barriers that lead to children being ZD and UI in the country. Time period for the study was December 2022-May 2023. The study methodology encompassed secondary data analysis using data from national surveys, primary data collection and analysis via a lot quality assurance sampling (LQAS) survey and also, qualitative data collection and analysis. Study population included caregivers of children aged 4.5 months (4 months 15 days) to 23 months for the LQAS survey. The qualitative component included policymakers, program managers and service providers working in immunization as well as mothers in the selected study areas who had a living child aged less than 2 years as the study population. Our data analysis confirms existence of ZD and UI children in areas which were categorized into haor (wetlands), hilly, char (sandy/silty land surrounded by water), coastal, plain land and urban slums. Determinant analysis showed that the mother's level of education, antenatal visits made, and access to media were significantly associated with children being ZD or UI. Reproductive autonomy emerged as a key factor that had prominent impact on a child being ZD. The qualitative analysis indicated the importance of population migration, health workforce shortages and lack of access to transportation as prominent barriers to immunization. Notably, the methods and approaches used in this study are both effective and easily replicable to identify ZD and UI children. The drivers of ZD and UI along with the barriers to immunization provide potential areas for intervention by policy-makers and can apprise about interventions to be tested in future implementation research.

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.

Investigating luminescence signals of pharmaceuticals and dietary supplements for emergency dosimetry

This study investigates the potential use of dietary supplements and pharmaceuticals containing magnesium, calcium or potassium for emergency dosimetry applications using the phenomenon of optically stimulated luminescence (OSL). Signal measurements were carried out using different stimulation wavelengths, and blue light stimulation was found to be the most efficient. More than half of the samples exhibited a measurable OSL signal and relatively high radiation sensitivity compared to other previously measured emergency detectors. Moreover, samples generally demonstrated a linear dose response. Possible causes of their high zero-dose signal were investigated: mechanical processing and UV light excitation. As variability in sensitivity was observed, the test-dose protocol was used during measurements. Furthermore, the study showed a significant loss of OSL signal intensity within 24 h after irradiation, which suggests the necessity for a fading correction. Finally, a dose recovery test was performed to evaluate the materials and the test-dose protocol under realistic conditions. The findings indicate the potential for using pharmaceuticals and dietary supplements in the event of a radiation emergency due to their dosimetric properties and ease of obtaining.

Building Data Triangulation Capacity for Routine Immunization and Vaccine Preventable Disease Surveillance Programs to Identify Immunization Coverage Inequities.

The Expanded Programme on Immunization (EPI) and Vaccine Preventable Disease (VPD) Surveillance (VPDS) programs generate multiple data sources (e.g., routine administrative data, VPD case data, and coverage surveys). However, there are challenges with the use of these siloed data for programmatic decision-making, including poor data accessibility and lack of timely analysis, contributing to missed vaccinations, immunity gaps, and, consequently, VPD outbreaks in populations with limited access to immunization and basic healthcare services. Data triangulation, or the integration of multiple data sources, can be used to improve the availability of key indicators for identifying immunization coverage gaps, under-immunized (UI) and un-immunized (zero-dose (ZD)) children, and for assessing program performance at all levels of the healthcare system. Here, we describe the data triangulation processes, prioritization of indicators, and capacity building efforts in Bangladesh, Nigeria, and Rwanda. We also describe the analyses used to generate meaningful data, key indicators used to identify immunization coverage inequities and performance gaps, and key lessons learned. Triangulation processes and lessons learned may be leveraged by other countries, potentially leading to programmatic changes that promote improved access and utilization of vaccination services through the identification of UI and ZD children.

Prevalence of and factors associated with zero-dose and under-immunized children in selected areas of Bangladesh: Findings from Lot Quality Assurance Sampling Survey

BackgroundIn the era of Gavi’s 5.0 vision of “leaving no one behind with immunization”, childhood routine vaccination in missed communities is considered as a priority concern. Despite having a success story at the national level, low uptake of immunization is still persistent in selected pocket areas of Bangladesh. However, prevalence and the associated factors of zero-dose (ZD) and under-immunization (UI) are still unknown at those geo-pockets of Bangladesh. Thus, the study aims to report and identify the factors associated with ZD and UI in selected geographical locations. MethodsThis study used data from a Lot Quality Assurance Sampling (LQAS) survey where 504 households from 18 clusters of four hard to reach (HTR) and one urban slum were included. Caregivers of children aged 4.5 to 23 months were interviewed. Three outcome variables- ZD, UI and ZD/UI were considered and several related attributes were considered as independent variables. Data were analyzed through bivariate analysis, binary logistic regression and dominance analysis. ResultsOverall, 32% of the children were either ZD (8%) or UI (26%) in the selected areas. The adjusted odds of ZD/UI for urban slum and haor (wetlands) areas were 5.62 and 3.61 respectively considering coastal areas as reference. However, distance of nearest EPI center, availability of EPI card, age of caregivers, education and occupation of mother and number of earning members in household were influential factors for ZD/UI. According to dominance analysis, availability of EPI card can explain the most of the variation of ZD/UI in this study. ConclusionThe study findings highlight the high prevalence ZD/UI in certain geo-pockets of the country. It provided a powerful insight of current situation and associated factors in regards to ZD/UI in the country which will help policy-makers and programme managers in designing programmes to reduce missed communities in Bangladesh.

Gibberellic acid in the ‘Cabernet Sauvignon’ grape: effects on grape cluster morphology and wine quality

‘Cabernet Sauvignon’ is a commonly produced and consumed variety of grapes in Brazil, although late sprouting and flowering negatively affect wine production, hindering the production of elegant and balanced wines, especially in high-altitude regions of Santa Catarina. Therefore, this study sought to evaluate the effects of gibberellic acid (GA3) on reducing and eliminating ‘Cabernet Sauvignon’ grape berry seeds and evaluate the physicochemical parameters of the wine produced in Serra Catarinense. The experiments were conducted in a commercial vineyard. The treatments were 0.0, 40.0, and 80.0 mg L-1 of GA3 in the 2019/20 season and 0.0, 20.0, and 40.0 mg L-1 of GA3 in the 2020/21 season. The applications were performed in full bloom. The characteristics evaluated were cluster weight, berry diameter, berry mass, number of seeds per berry, seed mass, peel:pulp ratio, cluster length, cluster compaction index, rachis mass, and berries per cluster. In both harvests, the zero dose of GA3 was related to greater cluster compaction, berry and cluster mass, and seeds per berry. In the 2019/20 harvest, 80 mg L-1 of GA3 was correlated to must total soluble sugar, wine acidity, must acidity, color parameter at 520 nm, and color intensity. In the last harvest, the color parameters were more correlated with the highest GA3 dose, showing that this growth regulator increased free anthocyanins and total polyphenols. Moreover, 20–80 mg L-1 of GA3 reduced the number and size of seeds but increased the tannin content in one harvest. Bunch compaction, cluster weight, diameter, and berry weight were reduced using GA3. Lastly, 20 and 40 mg L-1 of GA3 increased the total polyphenols and monomeric anthocyanins in the wine.

Understanding household-level risk factors for zero dose immunization in 82 low- and middle-income countries.

In 2021, an estimated 18 million children did not receive a single dose of routine vaccinations and constitute the population known as zero dose children. There is growing momentum and investment in reaching zero dose children and addressing the gross inequity in the reach of immunization services. To effectively do so, there is an urgent need to characterize more deeply the population of zero dose children and the barriers they face in accessing routine immunization services. We utilized the most recent DHS and MICS data spanning 2011 to 2020 from low, lower-middle, and upper-middle income countries. Zero dose status was defined as children aged 12-23 months who had not received any doses of BCG, DTP-containing, polio, and measles-containing vaccines. We estimated the prevalence of zero-dose children in the entire study sample, by country income level, and by region, and characterized the zero dose population by household-level factors. Multivariate logistic regressions were used to determine the household-level sociodemographic and health care access factors associated with zero dose immunization status. To pool multicountry data, we adjusted the original survey weights according to the country's population of children 12-23 months of age. To contextualize our findings, we utilized United Nations Population Division birth cohort data to estimate the study population as a proportion of the global and country income group populations. We included a total of 82 countries in our univariate analyses and 68 countries in our multivariate model. Overall, 7.5% of the study population were zero dose children. More than half (51.9%) of this population was concentrated in African countries. Zero dose children were predominantly situated in rural areas (75.8%) and in households in the lowest two wealth quintiles (62.7%) and were born to mothers who completed fewer than four antenatal care (ANC) visits (66.5%) and had home births (58.5%). Yet, surprisingly, a considerable proportion of zero dose children's mothers did receive appropriate care during pregnancy (33.5% of zero dose children have mothers who received at least 4 ANC visits). When controlled for other factors, children had three times the odds (OR = 3.00, 95% CI: 2.72, 3.30) of being zero dose if their mother had not received any tetanus injections, 2.46 times the odds (95% CI: 2.21, 2.74) of being zero dose if their mother had not received any ANC visits, and had nearly twice the odds (OR = 1.87, 95% CI: 1.70, 2.05) of being zero dose if their mother had a home delivery, compared to children of mothers who received at least 2 tetanus injections, received at least 4 ANC visits, and had a facility delivery, respectively. A lack of access to maternal health care was a strong risk factor of zero dose status and highlights important opportunities to improve the quality and integration of maternal and child health programs. Additionally, because a substantial proportion of zero dose children and their mothers do receive appropriate care, approaches to reach zero dose children should incorporate mitigating missed opportunities for vaccination.

Missed opportunities: Reducing zero dose children among the urban poor after COVID, Mumbai India, 2022

Reaching urban poor populations poses challenges for equitable immunization coverage. Furthermore, COVID disrupted routine immunization services. In Mumbai, India, first dose diphtheria tetanus pertussis containing vaccine (DTPCV1)coverage dropped from 88% (2019) to 76% (2021).We identified and characterized 125 zero-dose (those withoutDTPCV1)migrant children in urban Mumbai in October 2022.Almost half were born elsewhere than Mumbai; 53% resided at their present location for less than a year. More than half were 12–59 months of age, well-beyond the age for first routine childhood immunizations.Three of four zero dose children had received birth dose vaccination in the hospital; but failed to receive DTPCV1. Vaccine hesitancy, awareness gaps and operational issues were common reasons for non-vaccination. Despite frequent visits to health facilities for illness,only a third of facility staff asked or advised parents about vaccination.Missed opportunities were much more common in private than government facilities.For the vast majority (88%), residential sites were included in local routine immunization micro-plans and distances to immunization sites were short (less than 1 km for 94 % of families).However, planned session frequency was inadequate half of the time.Expanded efforts to reach migrant urban poor children are needed to ensure vaccine equity.

Defining the Zero Dose Child: A Comparative Analysis of Two Approaches and Their Impact on Assessing the Zero Dose Burden and Vulnerability Profiles across 82 Low- and Middle-Income Countries.

While there is a coordinated effort around reaching zero dose children and closing existing equity gaps in immunization delivery, it is important that there is agreement and clarity around how 'zero dose status' is defined and what is gained and lost by using different indicators for zero dose status. There are two popular approaches used in research, program design, and advocacy to define zero dose status: one uses a single vaccine to serve as a proxy for zero dose status, while another uses a subset of vaccines to identify children who have missed all routine vaccines. We provide a global analysis utilizing the most recent publicly available DHS and MICS data from 2010 to 2020 to compare the number, proportion, and profile of children aged 12 to 23 months who are 'penta-zero dose' (have not received the pentavalent vaccine), 'truly' zero dose (have not received any dose of BCG, polio, pentavalent, or measles vaccines), and 'misclassified' zero dose children (those who are penta-zero dose but have received at least one other vaccine). Our analysis includes 194,829 observations from 82 low- and middle-income countries. Globally, 14.2% of children are penta-zero dose and 7.5% are truly zero dose, suggesting that 46.5% of penta-zero dose children have had at least one contact with the immunization system. While there are similarities in the profile of children that are penta-zero dose and truly zero dose, there are key differences between the proportion of key characteristics among truly zero dose and misclassified zero dose children, including access to maternal and child health services. By understanding the extent of the connection zero dose children may have with the health and immunization system and contrasting it with how much the use of a more feasible definition of zero dose may underestimate the level of vulnerability in the zero dose population, we provide insights that can help immunization programs design strategies that better target the most disadvantaged populations. If the vulnerability profiles of the truly zero dose children are qualitatively different from that of the penta-zero dose children, then failing to distinguish the truly zero dose populations, and how to optimally reach them, may lead to the development of misguided or inefficient strategies for vaccinating the most disadvantaged population of children.

Analysis of global routine immunisation coverage shows disruption and stagnation during the first two-years of the COVID-19 pandemic with tentative recovery in 2022

Whilst it is now widely recognised that routine immunisation (RI) was disrupted by the COVID-19 pandemic in 2020, and further so in 2021, the extent of continued interruptions in 2022 and/or rebounds to previous trends remains unclear.We modelled country-specific RI trends using validated estimates of national coverage from the World Health Organisation and United Nation Children’s Fund for 182 countries (accounting for > 97% of children globally), to project expected diphtheria, tetanus, and pertussis-containing vaccine first-dose (DTP1), third-dose (DTP3) and measles-containing vaccine first-dose (MCV1) coverage for 2020–2022 based on pre-pandemic trends (from 2000 to 2019).We provide further evidence of peak pandemic immunisation disruption in 2021, followed by tentative recovery in 2022. We report a 3.4% (95 %CI: [2.5%; 4.4%]) decline in global DTP3 coverage in 2021 compared to 2000–2019 trends, from an expected 89.8% to reported 86.4%. This coverage gap reduced to a 2.7% (95 %CI: [1.8%; 3.6%]) decline in 2022, with reported coverage rising to 87.2%. Similar results were seen for DTP1 and MCV1. Whilst partial rebounds are encouraging, global coverage decline translates to a 17-year setback in RI to 2005 levels, and the majority of countries retain coverage at or lower than pre-pandemic levels. The Americas, Africa, and Asia were the most impacted regions; and low- and middle-income countries the most affected income groups.The number of annual Zero Dose (ZD) children – indicating those receiving no immunisations – increased from 12.1 million (M) globally in 2019 to a peak of 16.7 M in 2021, then reduced to 13.1 M in 2022. Overall, we estimate an excess of 8.8 M ZD children cumulatively in 2020–2022 compared to pre-pandemic levels.This work can be used as an objective baseline to inform future interventions to prioritise and target interventions, and facilitate catch-up of growing populations of under- and un-immunised children.

Reasons for Being "Zero-Dose and Under-Vaccinated" among Children Aged 12-23 Months in the Democratic Republic of the Congo.

(1) Introduction: The Democratic Republic of the Congo (DRC) has one of the largest cohorts of un- and under-vaccinated children worldwide. This study aimed to identify and compare the main reasons for there being zero-dose (ZD) or under-vaccinated children in the DRC. (2) Methods: This is a secondary analysis derived from a province-level vaccination coverage survey conducted between November 2021 and February 2022; this survey included questions about the reasons for not receiving one or more vaccines. A zero-dose child (ZD) was a person aged 12-23 months not having received any pentavalent vaccine (diphtheria-tetanus-pertussis-Hemophilus influenzae type b (Hib)-Hepatitis B) as per card or caregiver recall and an under-vaccinated child was one who had not received the third dose of the pentavalent vaccine. The proportions of the reasons for non-vaccination were first presented using the WHO-endorsed behavioral and social drivers for vaccination (BeSD) conceptual framework and then compared across the groups of ZD and under-vaccinated children using the Rao-Scott chi-square test; analyses were conducted at province and national level, and accounting for the sample approach. (3) Results: Of the 51,054 children aged 12-23 m in the survey sample, 19,676 ZD and under-vaccinated children were included in the study. For the ZD children, reasons related to people's thinking and feelings were cited as 64.03% and those related to social reasons as 31.13%; both proportions were higher than for under-vaccinated children (44.7% and 26.2%, respectively, p < 0.001). Regarding intentions to vaccinate their children, 82.15% of the parents/guardians of the ZD children said they wanted their children to receive "none" of the recommended vaccines, which was significantly higher than for the under-vaccinated children. In contrast, "practical issues" were cited for 35.60% of the ZD children, compared to 55.60% for the under-vaccinated children (p < 0.001). The distribution of reasons varied between provinces, e.g., 12 of the 26 provinces had a proportion of reasons for the ZD children relating to practical issues that was higher than the national level. (4) Conclusions: reasons provided for non-vaccination among the ZD children in the DRC were largely related to lack of parental/guardian motivation to have their children vaccinated, while reasons among under-vaccinated children were mostly related to practical issues. These results can help inform decision-makers to direct vaccination interventions.

"Zero Dose" Children in the Democratic Republic of the Congo: How Many and Who Are They?

(1) Background: The Democratic Republic of the Congo (DRC) is one of the countries with the highest number of never vaccinated or "zero-dose" (ZD) children in the world. This study was conducted to examine the proportion of ZD children and associated factors in the DRC. (2) Methods: Child and household data from a provincial-level vaccination coverage survey conducted between November 2021-February 2021 and 2022 were used. ZD was defined as a child aged 12 to 23 months who had not received any dose of pentavalent (diphtheria-tetanus-pertussis-Haemophilus influenzae type b (Hib)-Hepatitis B) vaccine (by card or recall). The proportion of ZD children was calculated and associated factors were explored using logistic regression, taking into account the complex sampling approach. (3) Results: The study included 51,054 children. The proportion of ZD children was 19.1% (95%CI: 19.0-19.2%); ZD ranged from 62.4% in Tshopo to 2.4% in Haut Lomami. After adjustment, being ZD was associated with low level of maternal education and having a young mother/guardian (aged ≤ 19 years); religious affiliation (willful failure to disclose religious affiliation as the highest associated factor compared to being Catholic, followed by Muslims, revival/independent church, Kimbanguist, Protestant); proxies for wealth such as not having a telephone or a radio; having to pay for a vaccination card or for another immunization-related service; not being able to name any vaccine-preventable disease. A child's lack of civil registration was also associated with being ZD. (4) Conclusions: In 2021, one in five children aged 12-23 months in DRC had never been vaccinated. The factors associated with being a ZD child suggest inequalities in vaccination that must be further explored to better target appropriate interventions.

Multivariate Assessment of Vaccine Equity in Cambodia: A Longitudinal VERSE Tool Case Study Using Demographic and Health Survey 2004, 2010, and 2014.

Cambodia has exhibited great progress in achieving high coverage in nationally recommended immunizations. As vaccination program managers plan interventions to reach last-mile children, it is important to consider issues of equity immunization priority setting. In this analysis, we apply the VERSE Equity Tool to Cambodia's Demographic and Health Survey for the years 2004, 2010, and 2014 to evaluate multivariate equity in vaccine coverage for 11 vaccination statuses, emphasizing the results of the 2014 survey for MCV1, DTP3, fully immunized for age (FULL), and zero dose (ZERO). The largest drivers of vaccination inequity are socioeconomic status and the educational attainment of the child's mother. MCV1, DTP3, and FULL exhibit increasing levels of both coverage and equity with increasing survey years. The national composite Wagstaff concentration index values from the 2014 survey for DTP3, MCV1, ZERO, and FULL are 0.089, 0.068, 0.573, and 0.087, respectively. The difference in vaccination status coverage between the most and least advantaged quintiles of Cambodia's population, using multivariate ranking criteria, is 23.5% for DTP3, 19.5% for MCV1, 9.1% for ZERO, and 30.3% for FULL. By utilizing these VERSE Equity Tool outputs, immunization program leaders in Cambodia can identify subnational regions in need of targeted interventions.

A TL study of protective glasses of mobile phones for retrospective dosimetry

Several studies have shown that certain components of mobile phones, such as electronic components, display or touch screen glass, are suitable as emergency dosimeters in case of radiological incidents. However, so far the methods are frequently destructive and in case of a dose assessment the mobile phone will be destroyed. In order to overcome this problem, alternative materials need to be sought and further research is necessary. Building on results of a previous study, we further investigated protective glasses in this work, which have become an alternative material for dose reconstruction. Protective glasses are easy to sample and cheap, have become very popular to protect the surface of phones, can be easily replaced without complete destruction of an expensive smartphone, thus a dose assessment method based on this material will potentially find much greater public acceptance. The aim of this study was to optimize the detection window by systematically investigating the radiation-induced TL signals and intrinsic zero dose signals. Using two selected detection windows, the long-term and optical stability of the TL signals were investigated. The set of nine different protective glass samples studied fell into two groups with different fading and optical bleaching characteristics. Further research is necessary in order to reduce the zero dose signal, to reinvestigate the dosimetric properties and to verify the final protocol using a realistic irradiation test.

An Equity Analysis of Zero-Dose Children in India Using the National Family Health Survey Data: Status, Challenges, and Next Steps.

Background While immunization programs across the world have made considerable progress, children and communities continue to be beyond the reach of healthcare services. Globally, they are now referred to as zero-dose (ZD) children (those who have not received a single dose of diphtheria, pertussis, and tetanus-containing vaccine). Pre-COVID-19 pandemic analyses suggest that nearly 50% of vaccine-preventable deaths occur among ZD children. Two-thirds of these children live in extremely poor households suffering from multiple deprivations including lack of access to reproductive health services, water, and sanitation. Hence, ZD childrenhave now been prioritized as a key cohort for identification and integration with the health systems as we build back from the pandemic. Methodology Extracting data from the last two National Family Health Survey (NFHS) rounds (NFHS 4, 2015-2016 and NFHS 5, 2019-2021), this study aims to ascertain the status of ZD children aged 12-23 months in India, the challenges, and the necessary action agenda going forward. Data were analyzed for equity determinants such as gender, place of residence, religion, birth order, caste, and mother's schooling. Key determinants included the change in ZD prevalence at the national, state, and district levels; variations across equity parameters and states with maximum improvements; and disparity across these indicators. A correlation analysis was also conducted to understand the nature of the association between ZD prevalence and critical maternal and child health indicators. Results The overall ZD prevalence between the two rounds was reduced by 4.1% (10.5-6.4%). A total of 26 states in the country reported a ZD prevalence of <10% in NFHS 5 compared to 18 in NFHS 4. In total, 324 districts reported a ZD prevalence of <5%, and 145 districts reported a prevalence of >10%. The equity parameters reflected a slow-footed reduction among ZD for girl children, across urban geographies, firstborn children, mothers with 12 or more years of schooling, and children in families with the highest wealth quintiles. A negative correlation accentuated between the two NFHS rounds was established between first-trimester registration, four or more antenatal visits, institutional deliveries, and ZD prevalence. Conclusions The findings point toward sustained improvement across key equity parameters, however, challenges do exist. Moreover, the impact of the pandemic on immunization programs across the globe and in India is bound to halt and reverse the progress and potentiate further inequities. It is thus imperative that continued and augmented efforts are continued to identify, integrate, and immunize ZD children, families, and communities.

Mapping of Pro-Equity Interventions Proposed by Immunisation Programs in Gavi Health Systems Strengthening Grants.

Reaching zero-dose (ZD) children, operationally defined as children who have not received a first dose of the diphtheria, tetanus, and pertussis (DTP1) vaccine, is crucial to increase equitable immunisation coverage and access to primary health care. However, little is known about the approaches already taken by countries to improve immunisation equity. We reviewed all Health System Strengthening (HSS) proposals submitted by Gavi-supported countries from 2014 to 2021 inclusively and extracted information on interventions favouring equity. Pro-equity interventions were mapped to an analytical framework representing Gavi 5.0 programmatic guidance on reaching ZD children and missed communities. Data from keyword searches and manual screening were extracted into an Excel database. Open format responses were analysed using inductive and deductive thematic coding. Data analysis was conducted using Excel and R. Of the 56 proposals included, 51 (91%) included at least one pro-equity intervention. The most common interventions were conducting outreach sessions, tailoring the location of service delivery, and partnerships. Many proposals had "bundles" of interventions, most often involving outreach, microplanning and community-level education activities. Nearly half prioritised remote-rural areas and only 30% addressed gender-related barriers to immunisation. The findings can help identify specific interventions on which to focus future evidence syntheses, case studies and implementation research and inform discussions on what may or may not need to change to better reach ZD children and missed communities moving forward.

Mother’s Awareness about Zero Dose of Hepatitis B Vaccination for their New Born Baby at Birth

Mother’s Awareness about Zero Dose of Hepatitis B Vaccination for their New Born Baby at Birth

Prevalence, geographical distribution and factors associated with pentavalent vaccine zero dose status among children in Sindh, Pakistan: analysis of data from the 2017 and 2018 birth cohorts enrolled in the provincial electronic immunisation registry

ObjectivesTo estimate the prevalence of zero dose children (who have not received any dose of pentavalent (diphtheria, tetanus, pertussis, Haemophilus influenzae type B and hepatitis B) vaccine by their first...

Pseudo Pelger-Huët anomalies as potential biomarkers for acute exposure radiation dose in rhesus macaques (Macaca mulatta)

Purpose The potential for malicious use of radiation, or radiation accidents could potentially lead to acute, high radiation doses to the public. Following acute accidental exposure to high doses of radiation, medical intervention is pivotal to the survivability of the patient, and the sooner the appropriate measures are taken the better the odds for survival. Early estimates of acute accidental radiation doses can be determined via biomarkers such as dicentric chromosome analysis or scenario reconstruction using computer software. However, both take valuable time and can be expensive. Increased frequencies of abnormal neutrophils in peripheral blood, referred to as pseudo Pelger-Huët anomalies (PPHAs), have been shown to be potential biomarkers of radiation exposure in several scenarios, including the 1958 Y-12 criticality accident and the radium dial painters. PPHAs are potentially a faster and cheaper quantitative biomarker for radiation exposure, and here they were evaluated in acutely exposed rhesus macaques. Methods and materials Peripheral blood smears from acutely exposed rhesus macaques were evaluated for the percentage of neutrophils that displayed the PPHA morphology using light microscopy. Irradiated animals received 0 to 8.5 Gy total body radiation using one of two strategies: (1) linear accelerator-produced 6 MV photons delivered at 80 cGy/minute; or (2) Cobalt 60-produced gamma irradiation delivered at 60 cGy/min. Zero dose animals were used to determine a baseline percentage of PPHAs, and blood smears taken periodically throughout the lifetime of exposed animals post-irradiation were used to determine the persistence and biokinetics of PPHAs. Results The baseline prevalence of the PPHA in rhesus macaques was determined to be 0.58 ± 0.46%. The dose-response curve with doses ranging from 0 Gy to 8.5 Gy (LD90/30) displayed a strong positive correlation between PPHA percentage and acute radiation dose (R 2 of 0.88 p = 3.62 × 10−22). Statistically significant differences were found when animals were separated into dose cohorts of 0, 4, 6.4–6.5, and 8–8.5 Gy. The biokinetics model utilized only 4 Gy exposures and blood smears taken periodically over 3.1 years post-irradiation. PPHA morphology increases quickly following irradiation and appears stable over 3.1 years post-irradiation. Conclusion PPHA morphology was confirmed to be present in rhesus macaques, a dose-response relationship was constructed, and it is stable over 3 years post-irradiation. This study demonstrates that PPHA analysis can be a fast and cheap method of biodosimetry. Future studies will work to determine the accuracy of dose determination and lower limits of detection.