Effectiveness of measles vaccination and vitamin A treatment

Inequalities in measles immunization coverage among two-year-olds in Sierra Leone, 2008-2019

BACKGROUND

Measles, a highly contagious and potentially fatal disease, remains a significant public health concern, particularly in low- and middle-income countries. Vaccination is the most effective way to prevent measles and achieving high immunization coverage is crucial for protecting children and communities. This study investigated the trends and inequalities in measles immunization coverage among two-year-olds in Sierra Leone between 2008 and 2019.

METHODS

The study utilized data from the Sierra Leone Demographic Health Surveys conducted in 2008, 2013, and 2019. The World Health Organisation Health Equity Assessment Toolkit was used to calculate various inequality measures, including Difference (D), Ratio (R), Population Attributable Risk (PAR), and Population Attributable Fraction (PAF). An inequality assessment was conducted for six stratifiers: age, economic status, level of education, place of residence, sex of the child, and sub-national province.

RESULTS

In Sierra Leone, measles immunization coverage increased between 2008 and 2013 and decreased slightly in 2019. In 2008, 66.2% of two-year-olds were immunized, which increased to 86.2% in 2013 and then fell slightly to 82.2% in 2019. There was a decrease in inequality for age from 4.2 percentage points in 2008 to 3.0 percentage points in 2019 (D = 4.2 in 2008 and 3.0 in 2019). Economic-related inequality decreased from 8.1 percentage points in 2008 to 7.5 percentage points in 2019 (D = 8.1 in 2008 and 7.5 in 2019). Inequality in education decreased from 10.3 percentage points in 2008 to 7.4 percentage points in 2019 based on results from the inequality measure D. For place of residence, inequality decreased from 6.0 percentage points in 2008 to 4.0 percentage points in 2019. For the child's sex, the inequality increased from 1.9 percentage points in 2008 to 4.5 percentage points in 2019. The PAF revealed that the setting average could have been 1.4% higher in 2008 and 2.7% higher in 2019 without the child's sex inequality. Provincial inequality decreased from 19.4 percentage points in 2008 to 16.9 percentage points in 2019 (D = 19.4 in 2008 and 16.9 in 2019).

CONCLUSION

The observed fluctuations in national measles immunization coverage for children under two underscore the need for sustained efforts in vaccination programs. While improvements in access based on age, socioeconomic status, education level, and place of residence suggest progress in reducing inequalities, the persistent provincial disparities, with a significant gap in 2019, highlight ongoing challenges that must be addressed to ensure equitable health outcomes. Additionally, the increase in inequalities based on the child's sex during the study period raises concerns about targeted interventions that may inadvertently neglect specific groups. These findings imply that policymakers must prioritize strategies that maintain high vaccination rates and focus on closing the geographical and sex-based gaps, particularly in underserved provinces and among vulnerable populations.

How does geographical diversity shape vaccine efficacy?

Vaccination is a cornerstone of public health, saving millions of lives each year by preventing a variety of infectious diseases. Yet, despite global vaccination efforts, emerging research highlights significant geographical disparities in vaccine efficacy and immunogenicity. These variations underscore the critical interplay between immunological factors and environmental, genetic, and nutritional elements across different populations. Our review article aimed to explore the multifactorial reasons behind geographical variations in vaccine efficacy. Also, this study has shown how important host factors like age, obesity, gender, and genetic diversity, especially within the major histocompatibility complex, are in determining how well a vaccine works. Nutritional status, namely deficiencies in micronutrients such as vitamins and zinc, and lifestyle factors including stress, sleep, alcohol consumption, and physical activity are also shown to have profound effects on vaccine-induced immunity. Importantly, our paper also brought to light the influence of microbial and ecological factors, such as the gut microbiome and environmental pollutants, on the immune system's response to vaccination. The findings emphasize the importance of tailoring vaccination strategies to accommodate the unique immunological landscapes shaped by geographical and societal factors. This tailored approach could enhance vaccine efficacy, reduce disparities in vaccine response, and ultimately contribute to the global fight against infectious diseases.

Measles resurgence in Armenia: unmasking health system vulnerabilities and crafting comprehensive eradication strategies - a review

Measles is an acute febrile illness associated with rashes, fever and life-threatening complications. It is a vaccine-preventable disease with the Measles Mumps Rubella(MMR) vaccine but a recent global trend unveils a resurgence of measles in various parts of the world including Armenia. Measles was declared eliminated from Armenia in 2021 before reports of local outbreaks surfaced in 2023. The WHO identified discrepancies in the vaccination coverage during COVID-19. Measles also poses a great financial burden as a public health issue worldwide. Sociocultural factors impacting measles transmission are maternal education, healthcare access, migration, vaccine hesitancy, and socioeconomic status (Table 3). Efforts to control and eradicate measles from Armenia are run by a collaborative approach of national and international health bodies such as United Nations Children's Fund (UNICEF), WHO, Global Vaccine Alliance (GAVI), and the Ministry of Health. Thus, the resurgence of measles can be managed through widespread patient education, innovative approaches, strengthening the healthcare system and addressing vaccine hesitancy, sociocultural barriers, and humanitarian emergencies. This review investigates the complicated dynamics of measles inside Armenia's health system in depth. A thorough examination of measles incidence and immunization patterns highlights the shift from few cases and high vaccination rates to a comeback caused by imported viruses. The causes of its recurrence have been thoroughly investigated, including reduced immunization programs and vaccine hesitancy. The research delves further into the 'One Health' idea, assessing the possibility of interspecies transmission among nonhuman primates and examining the environmental factors that influence measles transmission. Among the challenges are weaknesses within Armenia's health system as well as the possibility of interruptions from the COVID-19 outbreak. In measles vaccination status, the combination of maternal education, postnatal care, and socioeconomic variables exposes the larger drivers at work. The study concludes with a comprehensive set of public health policy recommendations covering vaccination promotion, surveillance, healthcare provider education, public awareness, international collaboration, data analysis, law enforcement, emergency preparedness, research, and coordination. The research sheds light on the tangled web of measles dynamics, health system resilience, and contextual subtleties via this multifaceted approach, inviting readers to investigate the multiple strategies required for eliminating measles in Armenia.

Using the Lives Saved Tool to inform global nutrition advocacy

Background

The global nutrition community has been interested in investigating investment strategies that could be used to promote an increased focus and investment in nutrition programming in low- and middle-income countries.

Methods

The Lives Saved Tool (LiST) was used to evaluate lives saved and the costs of nutrition interventions in nine high-burden countries. In this case study, we detail the analyses that were conducted with LiST and how the results were packaged to develop Nourish the Future - a five-year proposal for the US government to scale up lifesaving malnutrition interventions.

Results

Scaling up a proposed package of critical nutrition interventions including micronutrient supplementation for pregnant women, breastfeeding support, Vitamin A supplementation for children, and treatments for moderate and severe acute malnutrition is an effective and cost-effective way to avert millions of child deaths and stillbirths.

Conclusions

This is one of the few case studies that outlines how a nutrition modeling tool (in this case LiST) was used to engage in a prioritisation exercise to inform a US-based advocacy ask. We share reflections and provide practical insights into user motivation and preferences for existing and future modeling tool developers. This case study also emphasises how integral evidence translation and strategic advocacy are to ensure the use of the modeling results.

Impact and cost-effectiveness of measles vaccination through microarray patches in 70 low-income and middle-income countries: mathematical modelling and early-stage economic evaluation

BACKGROUND

Microarray patches (MAPs) are a promising technology being developed to reduce barriers to vaccine delivery based on needles and syringes (N&S). To address the evidence gap on the public health value of applying this potential technology to immunisation programmes, we evaluated the health impact on measles burden and cost-effectiveness of introducing measles-rubella MAPs (MR-MAPs) in 70 low-income and middle-income countries (LMICs).

METHODS

We used an age-structured dynamic model of measles transmission and vaccination to project measles cases, deaths and disability-adjusted life-years during 2030-2040. Compared with the baseline scenarios with continuing current N&S-based practice, we evaluated the introduction of MR-MAPs under different measles vaccine coverage projections and MR-MAP introduction strategies. Costs were calculated based on the ingredients approach, including direct cost of measles treatment, vaccine procurement and vaccine delivery. Model-based burden and cost estimates were derived for individual countries and country income groups. We compared the incremental cost-effectiveness ratios of introducing MR-MAPs to health opportunity costs.

RESULTS

MR-MAP introduction could prevent 27%-37% of measles burden between 2030 and 2040 in 70 LMICs, compared with the N&S-only immunisation strategy. The largest health impact could be achieved under lower coverage projection and accelerated introduction strategy, with 39 million measles cases averted. Measles treatment cost is a key driver of the net cost of introduction. In countries with a relatively higher income, introducing MR-MAPs could be a cost-saving intervention due to reduced treatment costs. Compared with country-specific health opportunity costs, introducing MR-MAPs would be cost-effective in 16%-81% of LMICs, depending on the MR-MAPs procurement prices and vaccine coverage projections.

CONCLUSIONS

Introducing MR-MAPs in LMICs can be a cost-effective strategy to revitalise measles immunisation programmes with stagnant uptake and reach undervaccinated children. Sustainable introduction and uptake of MR-MAPs has the potential to improve vaccine equity within and between countries and accelerate progress towards measles elimination.

Measles: Contemporary considerations for the emergency physician

Measles, or rubeola, is a highly contagious acute febrile viral illness. Despite the availability of an effective vaccine since 1963, measles outbreaks continue worldwide. This article seeks to provide emergency physicians with the contemporary knowledge required to rapidly diagnose potential measles cases and bolster public health measures to reduce ongoing transmission.

Health effects of routine measles vaccination and supplementary immunisation activities in 14 high-burden countries: a Dynamic Measles Immunization Calculation Engine (DynaMICE) modelling study

BACKGROUND

WHO recommends at least 95% population coverage with two doses of measles-containing vaccine (MCV). Most countries worldwide use routine services to offer a first dose of measles-containing vaccine (MCV1) and later, a second dose of measles-containing vaccine (MCV2). Many countries worldwide conduct supplementary immunisation activities (SIAs), offering vaccination to all people in a specific age range irrespective of previous vaccination history. We aimed to estimate the relative effects of each dose and delivery route in 14 countries with high measles burden.

METHODS

We used an age-structured compartmental dynamic model, the Dynamic Measles Immunization Calculation Engine (DynaMICE), to assess the effects of different vaccination strategies on measles susceptibility and burden during 2000-20 in 14 countries with high measles incidence (containing 53% of the global birth cohort and 78% of the global measles burden). Country-specific routine MCV1 and MCV2 coverage data during 1980-2020 were obtained from the WHO and UNICEF Estimates of National Immunization Coverage database for all modelled countries and SIA data were obtained from the WHO summary of measles and rubella SIAs. We estimated the incremental health effects of different vaccination strategies using prevented cases of measles and deaths from measles and their efficiency using the incremental number needed to vaccinate (NNV) to prevent an additional measles case.

FINDINGS

Compared with no vaccination, MCV1 implementation was estimated to have prevented 824 million cases of measles and 9·6 million deaths from measles, with a median NNV of 1·41 (IQR 1·35-1·44). Adding routine MCV2 to MCV1 was estimated to have prevented 108 million cases and 404 270 deaths, whereas adding SIAs to MCV1 was estimated to have prevented 256 million cases and 4·4 million deaths. Despite larger incremental effects, adding SIAs to MCV1 (median incremental NNV 6·02, 5·30-7·68) showed reduced efficiency compared with adding routine MCV2 (5·41, 4·76-6·11).

INTERPRETATION

Vaccination strategies, including non-selective SIAs, reach a greater proportion of children who are unvaccinated and reduce measles burden more than MCV2 alone, but efficiency is lower because of the wide age range targeted by SIAs. This analysis provides information to help improve the health effects and efficiency of measles vaccination strategies. The interplay between MCV1, MCV2, and SIAs should be considered when planning future measles vaccination strategies.

FUNDING

Gavi, the Vaccine Alliance and the Bill & Melinda Gates Foundation.

Carotenoids: Role in Neurodegenerative Diseases Remediation

Numerous factors can contribute to the development of neurodegenerative disorders (NDs), such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, Huntington's disease, and multiple sclerosis. Oxidative stress (OS), a fairly common ND symptom, can be caused by more reactive oxygen species being made. In addition, the pathological state of NDs, which includes a high number of protein aggregates, could make chronic inflammation worse by activating microglia. Carotenoids, often known as "CTs", are pigments that exist naturally and play a vital role in the prevention of several brain illnesses. CTs are organic pigments with major significance in ND prevention. More than 600 CTs have been discovered in nature, and they may be found in a wide variety of creatures. Different forms of CTs are responsible for the red, yellow, and orange pigments seen in many animals and plants. Because of their unique structure, CTs exhibit a wide range of bioactive effects, such as anti-inflammatory and antioxidant effects. The preventive effects of CTs have led researchers to find a strong correlation between CT levels in the body and the avoidance and treatment of several ailments, including NDs. To further understand the connection between OS, neuroinflammation, and NDs, a literature review has been compiled. In addition, we have focused on the anti-inflammatory and antioxidant properties of CTs for the treatment and management of NDs.

Added value of the measles-rubella supplementary immunization activity in reaching unvaccinated and under-vaccinated children, a cross-sectional study in five Indian districts, 2018-20

INTRODUCTION

Supplementary immunization activities (SIAs) aim to interrupt measles transmission by reaching susceptible children, including children who have not received the recommended two routine doses of MCV before the SIA. However, both strategies may miss the same children if vaccine doses are highly correlated. How well SIAs reach children missed by routine immunization is a key metric in assessing the added value of SIAs.

METHODS

Children aged 9 months to younger than 5 years were enrolled in cross-sectional household serosurveys conducted in five districts in India following the 2017-2019 measles-rubella (MR) SIA. History of measles containing vaccine (MCV) through routine services or SIA was obtained from documents and verbal recall. Receipt of a first or second MCV dose during the SIA was categorized as "added value" of the SIA in reaching un- and under-vaccinated children.

RESULTS

A total of 1,675 children were enrolled in these post-SIA surveys. The percentage of children receiving a 1st or 2nd dose through the SIA ranged from 12.8% in Thiruvananthapuram District to 48.6% in Dibrugarh District. Although the number of zero-dose children prior to the SIA was small in most sites, the proportion reached by the SIA ranged from 45.8% in Thiruvananthapuram District to 94.9% in Dibrugarh District. Fewer than 7% of children remained measles zero-dose after the MR SIA (range: 1.1-6.4%) compared to up to 28% before the SIA (range: 7.3-28.1%).

DISCUSSION

We demonstrated the MR SIA provided considerable added value in terms of measles vaccination coverage, although there was variability across districts due to differences in routine and SIA coverage, and which children were reached by the SIA. Metrics evaluating the added value of an SIA can help to inform the design of vaccination strategies to better reach zero-dose or undervaccinated children.

Spatial analysis of measles vaccination coverage in the State of São Paulo

BACKGROUND

Measles is a contagious viral disease that seriously affects children. The measles vaccine is widely recommended in Brazil and in the world; however, the disease remains relevant for the health authorities. The aim of the present study was to evaluate first and second dose of measles vaccine coverage (VC) in the cities of São Paulo and its spatial dynamics between 2015 and 2020.

METHOD

In this mixed-type ecological study, we used secondary, public domain data from 2015 to 2020, extracted from the Digital Information System of the National Immunization Program, Mortality Information System and the National Live Birth Information System. After calculating the VC, the following four categories were created: very low, low, adequate, and high, and the spatial autocorrelation of VC was analyzed using the Global and Local Moran's statistics.

RESULTS

A steady decline in adherence to the vaccination was observed, which dynamically worsened until 2020, with a high number of cities fitting the classification of ineffective coverage and being potentially harmful to the effectiveness of the immunization activities of their neighbors.

CONCLUSION

A direct neighborhood pattern was observed between the units with low vaccination coverage, which implied that the reduction in measles VC was somehow related to and negatively influenced by the geographic location and social culture of these areas.

Measles in children: a re-emergence of the vaccine-preventable disease

Despite the availability of a safe and effective vaccine, measles remains an endemic in many countries and is the main cause of morbidity and mortality among young children. Therefore, the main objective of this study was to describe the most important aspects of measles that allow clinicians to identify suspected cases for timely diagnosis and treatment, which are essential to avoid inappropriate interventions and prevent complications. The measles virus is highly contagious, is transmitted through fomites and respiratory secretions, and remains active in the environment or on surfaces for several hours. Diagnosing measles can be difficult because most clinicians are unfamiliar as there have been few confirmed cases in recent years. Taking a complete medical history, while considering the clinical phases of measles, and a thorough physical examination can help guide the diagnosis, as the main characteristics of measles (fever and rash) can be seen in both infectious and non-infectious diseases. Treatment consists of three fundamental aspects: supportive care (management of fever and hydration), identification and treatment of associated complications, and prevention of disease spread through patient and family group education. It is important to ensure compliance with immunization policies and strategies globally to control the re-emergence of measles and increase in the burden of disease caused by the measles virus.

Modeling the relative risk of incidence and mortality of select vaccine-preventable diseases by wealth group and geographic region in Ethiopia

Immunization is one of the most effective public health interventions, saving millions of lives every year. Ethiopia has seen gradual improvements in immunization coverage and access to child health care services; however, inequalities in child mortality across wealth quintiles and regions remain persistent. We model the relative distributional incidence and mortality of four vaccine-preventable diseases (VPDs) (rotavirus diarrhea, human papillomavirus, measles, and pneumonia) by wealth quintile and geographic region in Ethiopia. Our approach significantly extends an earlier methodology, which utilizes the population attributable fraction and differences in the prevalence of risk and prognostic factors by population subgroup to estimate the relative distribution of VPD incidence and mortality. We use a linear system of equations to estimate the joint distribution of risk and prognostic factors in population subgroups, treating each possible combination of risk or prognostic factors as computationally distinct, thereby allowing us to account for individuals with multiple risk factors. Across all modeling scenarios, our analysis found that the poor and those living in rural and primarily pastoralist or agrarian regions have a greater risk than the rich and those living in urban regions of becoming infected with or dying from a VPD. While in absolute terms all population subgroups benefit from health interventions (e.g., vaccination and treatment), current unequal levels and pro-rich gradients of vaccination and treatment-seeking patterns should be redressed so to significantly improve health equity across wealth quintiles and geographic regions in Ethiopia.

Trends of the Global, Regional, and National Incidence of Measles, Vaccine Coverage, and Risk Factors in 204 Countries From 1990 to 2019

Background

Measles is a highly contagious disease that has caused global morbidity and mortality. Though great progress has been made in measles elimination, the resurgence of measles has been observed in recent years. As extant literature were mainly confined to data of local area, we conducted a systematic analysis to explore the trends of the incidence of measles, coverage rate, and the risk factors from 1990 to 2019 on global, regional, and national levels.

Methods

Data on cases of incidence, age standardized rate (ASR), vaccine coverage, and risk factors of measles were retrieved from the Global Burden of Disease (GBD) Study 2019 database. Estimated averaged percentage change (EAPC) of ASR was calculated to quantify the trends of measles incidence. Pearson correlation was applied to assess the association of EAPC and measles-containing vaccine coverage rate with socio-demographic index (SDI) in 2019, and the correlation between ASR and measles-containing vaccine coverage rate.

Results

Globally, there was a significant decrease in the number (84.18%) and ASR (6.13%, 95% CI: 5.41–6.84%) of measles incidence from 1990 to 2019. More than 80% of incidence cases were attributed to children under 5 and the proportion was highest in low SDI region. Countries and territories with low ASRs are mostly clustered in North America, Southern Latin America, and Western Europe, whereas those with high ASRs are mainly clustered in Africa, East Asia, and South Asia. Lower SDI was associated with higher ASR and lower vaccine coverage rate. The more the SDI value was further away from 0.6, the smaller the absolute value did EAPC have. Child wasting accounted for the most measles-related death cases, followed by child underweight, child stunting, and vitamin A deficiency.

Conclusions

Measles eradication is feasible, but urgently demands political commitment, financial support, and public engagement. In the context of COVID-19 pandemic and the global resurgence of measles, surveillance systems and routine immunization programs should be improved, while vaccine hesitancy needs to be addressed.

Trends and Treatment of Sub-Acute Sclerosing Panencephalitis: An Updated Review

Measles infection, caused by the “Rubeola” virus is a highly contagious disease with outrageously fatal consequences. Initiating with a variety of symptoms including fever, cough, conjunctivitis, and runny nose, it can lead to more severe sequelae including sub-acute sclerosing pan-encephalitis which is a potentially fatal and serious complication of measles. The lackluster vaccination processes in underdeveloped areas of the world due to suboptimal immunization programs, scarce resources, and insufficient political constancy still leads to increased cases of measles and its complications. A variety of management programs including the use of several medications have been introduced according to the literature in order to counter this dreadful disease. In this review article, we focus on assessment of the previous literature and discussing the possible treatment modalities of this currently irremediable disease.

The optimal vaccination strategy to control COVID-19: a modeling study in Wuhan City, China

Background

Reaching optimal vaccination rates is an essential public health strategy to control the coronavirus disease 2019 (COVID-19) pandemic. This study aimed to simulate the optimal vaccination strategy to control the disease by developing an age-specific model based on the current transmission patterns of COVID-19 in Wuhan City, China.

Methods

We collected two indicators of COVID-19, including illness onset data and age of confirmed case in Wuhan City, from December 2, 2019, to March 16, 2020. The reported cases were divided into four age groups: group 1, ≤ 14 years old; group 2, 15 to 44 years old; group 3, 44 to 64 years old; and group 4, ≥ 65 years old. An age-specific susceptible-exposed-symptomatic-asymptomatic-recovered/removed model was developed to estimate the transmissibility and simulate the optimal vaccination strategy. The effective reproduction number (R_eff) was used to estimate the transmission interaction in different age groups.

Results

A total of 47 722 new cases were reported in Wuhan City from December 2, 2019, to March 16, 2020. Before the travel ban of Wuhan City, the highest transmissibility was observed among age group 2 (R_eff = 4.28), followed by group 2 to 3 (R_eff = 2.61), and group 2 to 4 (R_eff = 1.69). China should vaccinate at least 85% of the total population to interrupt transmission. The priority for controlling transmission should be to vaccinate 5% to 8% of individuals in age group 2 per day (ultimately vaccinated 90% of age group 2), followed by 10% of age group 3 per day (ultimately vaccinated 90% age group 3). However, the optimal vaccination strategy for reducing the disease severity identified individuals ≥ 65 years old as a priority group, followed by those 45–64 years old.

Conclusions

Approximately 85% of the total population (nearly 1.2 billion people) should be vaccinated to build an immune barrier in China to safely consider removing border restrictions. Based on these results, we concluded that 90% of adults aged 15–64 years should first be vaccinated to prevent transmission in China.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s40249-021-00922-4.

Effect of evidence updates on key determinants of measles vaccination impact: a DynaMICE modelling study in ten high-burden countries

BACKGROUND

Model-based estimates of measles burden and the impact of measles-containing vaccine (MCV) are crucial for global health priority setting. Recently, evidence from systematic reviews and database analyses have improved our understanding of key determinants of MCV impact. We explore how representations of these determinants affect model-based estimation of vaccination impact in ten countries with the highest measles burden.

METHODS

Using Dynamic Measles Immunisation Calculation Engine (DynaMICE), we modelled the effect of evidence updates for five determinants of MCV impact: case-fatality risk, contact patterns, age-dependent vaccine efficacy, the delivery of supplementary immunisation activities (SIAs) to zero-dose children, and the basic reproduction number. We assessed the incremental vaccination impact of the first (MCV1) and second (MCV2) doses of routine immunisation and SIAs, using metrics of total vaccine-averted cases, deaths, and disability-adjusted life years (DALYs) over 2000-2050. We also conducted a scenario capturing the effect of COVID-19 related disruptions on measles burden and vaccination impact.

RESULTS

Incorporated with the updated data sources, DynaMICE projected 253 million measles cases, 3.8 million deaths and 233 million DALYs incurred over 2000-2050 in the ten high-burden countries when MCV1, MCV2, and SIA doses were implemented. Compared to no vaccination, MCV1 contributed to 66% reduction in cumulative measles cases, while MCV2 and SIAs reduced this further to 90%. Among the updated determinants, shifting from fixed to linearly-varying vaccine efficacy by age and from static to time-varying case-fatality risks had the biggest effect on MCV impact. While varying the basic reproduction number showed a limited effect, updates on the other four determinants together resulted in an overall reduction of vaccination impact by 0.58%, 26.2%, and 26.7% for cases, deaths, and DALYs averted, respectively. COVID-19 related disruptions to measles vaccination are not likely to change the influence of these determinants on MCV impact, but may lead to a 3% increase in cases over 2000-2050.

CONCLUSIONS

Incorporating updated evidence particularly on vaccine efficacy and case-fatality risk reduces estimates of vaccination impact moderately, but its overall impact remains considerable. High MCV coverage through both routine immunisation and SIAs remains essential for achieving and maintaining low incidence in high measles burden settings.

T Cell/B Cell Interactions in the Establishment of Protective Immunity

Follicular helper T cells (Tfh) are the T cell subset providing help to B cells for the generation of high-affinity antibodies and are therefore of key interest for the development of vaccination strategies against infectious diseases. In this review, we will discuss how the generation of Tfh cells and their interaction with B cells in secondary lymphoid organs can be optimized for therapeutic purposes. We will summarize different T cell subsets including Tfh-like peripheral helper T cells (Tph) capable of providing B cell help. In particular, we will highlight the novel concept of T cell/B cell interaction in non-lymphoid tissues as an important element for the generation of protective antibodies directly at the site of pathogen invasion.

Solubility of vitamin A in supercritical CO2: experimental study and thermodynamic modeling

One of the best methods of extracting Vitamin A, as a helper of the immune body system and vision, was measured in supercritical carbon dioxide (SC-CO₂); Mole fractions were gained at practical conditions in which the temperature was in the range of 303–323 K and the pressure range was 90–235 bar, respectively. Moreover, four Equation of States [Soave–Redlich–Kwong, Peng–Robinson, Stryjek–Vera and Dashtizadeh–Pazuki–Taghikhani–Ghotbi (DPTG)] were compared with the experimental data. Also, the mixing rules of Van der Waals (vdW1 and vdW2) selected to correlate the solubility data of vitamin A. The outcomes indicate that each of EOSs coupled with vdW2, as a method of estimating the physicochemical and critical properties, were correlated with the solubility data of vitamin A in SC-CO₂ with more accuracy, in comparison with vdW1. Among the cubic EOSs, the DPTG model with vdW2 generated the most suitable correlation with the percentage average absolute relative deviation (Average Absolute Relative Deviation%) of 6.

The Role of Nutrition in COVID-19 Susceptibility and Severity of Disease: A Systematic Review

BACKGROUND

Many nutrients have powerful immunomodulatory actions with the potential to alter susceptibility to coronavirus disease 2019 (COVID-19) infection, progression to symptoms, likelihood of severe disease, and survival.

OBJECTIVE

The aim was to review the latest evidence on how malnutrition across all its forms (under- and overnutrition and micronutrient status) may influence both susceptibility to, and progression of, COVID-19.

METHODS

We synthesized information on 13 nutrition-related components and their potential interactions with COVID-19: overweight, obesity, and diabetes; protein-energy malnutrition; anemia; vitamins A, C, D, and E; PUFAs; iron; selenium; zinc; antioxidants; and nutritional support. For each section we provide: 1) a landscape review of pertinent material; 2) a systematic search of the literature in PubMed and EMBASE databases, including a wide range of preprint servers; and 3) a screen of 6 clinical trial registries. All original research was considered, without restriction to study design, and included if it covered: 1) severe acute respiratory syndrome coronavirus (CoV) 2 (SARS-CoV-2), Middle East respiratory syndrome CoV (MERS-CoV), or SARS-CoV viruses and 2) disease susceptibility or 3) disease progression, and 4) the nutritional component of interest. Searches took place between 16 May and 11 August 2020.

RESULTS

Across the 13 searches, 2732 articles from PubMed and EMBASE, 4164 articles from the preprint servers, and 433 trials were returned. In the final narrative synthesis, we include 22 published articles, 38 preprint articles, and 79 trials.

CONCLUSIONS

Currently there is limited evidence that high-dose supplements of micronutrients will either prevent severe disease or speed up recovery. However, results of clinical trials are eagerly awaited. Given the known impacts of all forms of malnutrition on the immune system, public health strategies to reduce micronutrient deficiencies and undernutrition remain of critical importance. Furthermore, there is strong evidence that prevention of obesity and type 2 diabetes will reduce the risk of serious COVID-19 outcomes. This review is registered at PROSPERO as CRD42020186194.

Incorporating equity in infectious disease modeling: Case study of a distributional impact framework for measles transmission

INTRODUCTION

Deterministic compartmental models of infectious diseases like measles typically reflect biological heterogeneities in the risk of infection and severity to characterize transmission dynamics. Given the known association of socioeconomic status and increased vulnerability to infection and mortality, it is also critical that such models further incorporate social heterogeneities.

METHODS

Here, we aimed to explore the influence of integrating income-associated differences in parameters of traditional dynamic transmission models. We developed a measles SIR model, in which the Susceptible, Infected and Recovered classes were stratified by income quintile, with income-specific transmission rates, disease-induced mortality rates, and vaccination coverage levels. We further provided a stylized illustration with secondary data from Ethiopia, where we examined various scenarios demonstrating differences in transmission patterns by income and in distributional vaccination coverage, and quantified impacts on disparities in measles mortality.

RESULTS

The income-stratified SIR model exhibited similar dynamics to that of the traditional SIR model, with amplified outbreak peaks and measles mortality among the poorest income group. All vaccination coverage strategies were found to substantially curb the overall number of measles deaths, yet most considerably for the poorest, with select strategies yielding clear reductions in measles mortality disparities.

DISCUSSION

The incorporation of income-specific differences can reveal distinct outbreak patterns across income groups and important differences in the subsequent effects of preventative interventions like vaccination. Our case study highlights the need to extend traditional modeling frameworks (e.g. SIR models) to be stratified by socioeconomic factors like income and to consider ensuing income-associated differences in disease-related morbidity and mortality. In so doing, we build on existing tools and characterize ongoing challenges in achieving health equity.

What Affects Maternal Response to Measles Vaccinations? Examining the Health Beliefs Model (HBM)

Background: Renewed measles outbreaks in recent years indicate that despite the routine availability of vaccines for a disease that is considered contagious, dangerous and deadly, many anti-vaccinationists do not vaccinate their children, which consequently endangers public health. This study aimed to investigate the factors that influence mothers to vaccinate their children, and whether the Health Belief Model (HBM) could predict compliance or non-compliance. Methods: This was a quantitative correlational research, using a 40-item questionnaire administered to 181 mothers in Israel. Results: The findings indicated two main factors that affected mothers’ intention to vaccinate their children against measles: first, their perception of the vaccine’s advantages, and second, their perception of the severity of the disease. It was also found that the HBM variables significantly affected the intention to administer vaccines. Conclusion: Consequently, raising public awareness of the vaccine’s advantages and importance to preventing mass infection, as well as attempts by the health system and practitioners to understand the motivations of anti-vaccinationists (including health beliefs and cultural sensitivities) could significantly increase the percentage of vaccinated children, and eradicate the measles epidemic.

Vitamin A controls the allergic response through T follicular helper cell as well as plasmablast differentiation

BACKGROUND

Vitamin A regulates the adaptive immune response and a modulatory impact on type I allergy is discussed. The cellular mechanisms are largely unknown.

OBJECTIVE

To determine the vitamin A-responding specific lymphocyte reaction in vivo.

METHODS

Antigen-specific B and T lymphocytes were analyzed in an adoptive transfer airway inflammation mouse model in response to 9-cis retinoic acid (9cRA) and after lymphocyte-specific genetic targeting of the receptor RARα. Flow cytometry, quantitative PCR, next-generation sequencing, and specific Ig-ELISA were used to characterize the cells functionally.

RESULTS

Systemic 9cRA profoundly enhanced the specific IgA-secreting B-cell frequencies in the lung tissue and serum IgA while reducing serum IgE concentrations. RARα overexpression in antigen-specific B cells promoted differentiation into plasmablasts at the expense of germinal center B cells. In antigen-specific T cells, RARα strongly promoted the differentiation of T follicular helper cells followed by an enhanced germinal center response.

CONCLUSIONS

9cRA signaling via RARα impacts the allergen-specific immunoglobulin response directly by the differentiation of B cells and indirectly by promoting T follicular helper cells.

The importance of supplementary immunisation activities to prevent measles outbreaks during the COVID-19 pandemic in Kenya

BACKGROUND

The COVID-19 pandemic has disrupted routine measles immunisation and supplementary immunisation activities (SIAs) in most countries including Kenya. We assessed the risk of measles outbreaks during the pandemic in Kenya as a case study for the African Region.

METHODS

Combining measles serological data, local contact patterns, and vaccination coverage into a cohort model, we predicted the age-adjusted population immunity in Kenya and estimated the probability of outbreaks when contact-reducing COVID-19 interventions are lifted. We considered various scenarios for reduced measles vaccination coverage from April 2020.

RESULTS

In February 2020, when a scheduled SIA was postponed, population immunity was close to the herd immunity threshold and the probability of a large outbreak was 34% (8-54). As the COVID-19 contact restrictions are nearly fully eased, from December 2020, the probability of a large measles outbreak will increase to 38% (19-54), 46% (30-59), and 54% (43-64) assuming a 15%, 50%, and 100% reduction in measles vaccination coverage. By December 2021, this risk increases further to 43% (25-56), 54% (43-63), and 67% (59-72) for the same coverage scenarios respectively. However, the increased risk of a measles outbreak following the lifting of all restrictions can be overcome by conducting a SIA with ≥ 95% coverage in under-fives.

CONCLUSION

While contact restrictions sufficient for SAR-CoV-2 control temporarily reduce measles transmissibility and the risk of an outbreak from a measles immunity gap, this risk rises rapidly once these restrictions are lifted. Implementing delayed SIAs will be critical for prevention of measles outbreaks given the roll-back of contact restrictions in Kenya.

Mega-map of systematic reviews and evidence and gap maps on the interventions to improve child well-being in low- and middle-income countries

Background

Despite a considerable reduction in child mortality, nearly six million children under the age of five die each year. Millions more are poorly nourished and in many parts of the world, the quality of education remains poor. Children are at risk from multiple violations of their rights, including child labour, early marriage, and sexual exploitation. Research plays a crucial role in helping to close the remaining gaps in child well-being, yet the global evidence base for interventions to meet these challenges is mostly weak, scattered and often unusable by policymakers and practitioners. This mega-map encourages the generation and use of rigorous evidence on effective ways to improve child well-being for policy and programming.

Objectives

The aim of this mega-map is to identify, map and provide an overview of the existing evidence synthesis on the interventions aimed at improving child well-being in low- and middle-income countries (LMICs).

Methods

Campbell evidence and gap maps (EGMs) are based on a review of existing mapping standards (Saran & White, 2018) which drew in particular of the approach developed by 3ie (Snilstveit, Vojtkova, Bhavsar, & Gaarder, 2013). As defined in the Campbell EGM guidance paper; "Mega-map is a map of evidence synthesis, that is, systematic reviews, and does not include primary studies" (Campbell Collaboration, 2020). The mega-map on child well-being includes studies with participants aged 0-18 years, conducted in LMICs, and published from year 2000 onwards. The search followed strict inclusion criteria for interventions and outcomes in the domains of health, education, social work and welfare, social protection, environmental health, water supply and sanitation (WASH) and governance. Critical appraisal of included systematic reviews was conducted using "A Measurement Tool to Assess Systematic Reviews"-AMSTAR-2 rating scale (Shea, et al., 2017).

Results

We identified 333 systematic reviews and 23 EGMs. The number of studies being published has increased year-on-year since 2000. However, the distribution of studies across World Bank regions, intervention and outcome categories are uneven. Most systematic reviews examine interventions pertaining to traditional areas of health and education. Systematic reviews in these traditional areas are also the most funded. There is limited evidence in social work and social protection. About 69% (231) of the reviews are assessed to be of low and medium quality. There are evidence gaps with respect to key vulnerable populations, including children with disabilities and those who belong to minority groups.

Conclusion

Although an increasing number of systematic reviews addressing child well-being topics are being published, some clear gaps in the evidence remain in terms of quality of reviews and some interventions and outcome areas. The clear gap is the small number of reviews focusing explicitly on either equity or programmes for disadvantaged groups and those who are discriminated against.

Routine childhood immunisation during the COVID-19 pandemic in Africa: a benefit-risk analysis of health benefits versus excess risk of SARS-CoV-2 infection

BACKGROUND

National immunisation programmes globally are at risk of suspension due to the severe health system constraints and physical distancing measures in place to mitigate the ongoing COVID-19 pandemic. We aimed to compare the health benefits of sustaining routine childhood immunisation in Africa with the risk of acquiring severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection through visiting routine vaccination service delivery points.

METHODS

We considered a high-impact scenario and a low-impact scenario to approximate the child deaths that could be caused by immunisation coverage reductions during COVID-19 outbreaks. In the high-impact scenario, we used previously reported country-specific child mortality impact estimates of childhood immunisation for diphtheria, tetanus, pertussis, hepatitis B, Haemophilus influenzae type b, Streptococcus pneumoniae, rotavirus, measles, meningitis A, rubella, and yellow fever to approximate the future deaths averted before 5 years of age by routine childhood vaccination during a 6-month COVID-19 risk period without catch-up campaigns. In the low-impact scenario, we approximated the health benefits of sustaining routine childhood immunisation on only the child deaths averted from measles outbreaks during the COVID-19 risk period. We assumed that contact-reducing interventions flattened the outbreak curve during the COVID-19 risk period, that 60% of the population will have been infected by the end of that period, that children can be infected by either vaccinators or during transport, and that upon child infection the whole household will be infected. Country-specific household age structure estimates and age-dependent infection-fatality rates were applied to calculate the number of deaths attributable to the vaccination clinic visits. We present benefit-risk ratios for routine childhood immunisation, with 95% uncertainty intervals (UIs) from a probabilistic sensitivity analysis.

FINDINGS

In the high-impact scenario, for every one excess COVID-19 death attributable to SARS-CoV-2 infections acquired during routine vaccination clinic visits, 84 (95% UI 14-267) deaths in children could be prevented by sustaining routine childhood immunisation in Africa. The benefit-risk ratio for the vaccinated children is 85 000 (4900-546 000), for their siblings (<20 years) is 75 000 (4400-483 000), for their parents or adult carers (aged 20-60 years) is 769 (148-2700), and for older adults (>60 years) is 96 (14-307). In the low-impact scenario that approximates the health benefits to only the child deaths averted from measles outbreaks, the benefit-risk ratio to the households of vaccinated children is 3 (0-10); if the risk to only the vaccinated children is considered, the benefit-risk ratio is 3000 (182-21 000).

INTERPRETATION

The deaths prevented by sustaining routine childhood immunisation in Africa outweigh the excess risk of COVID-19 deaths associated with vaccination clinic visits, especially for the vaccinated children. Routine childhood immunisation should be sustained in Africa as much as possible, while considering other factors such as logistical constraints, staff shortages, and reallocation of resources during the COVID-19 pandemic.

FUNDING

Gavi, the Vaccine Alliance; Bill & Melinda Gates Foundation.

Association of vitamin A deficiency with early childhood stunting in Uganda: A population-based cross-sectional study

BACKGROUND

Despite the high prevalence of childhood protein-energy malnutrition and vitamin A deficiency in sub-Saharan Africa, their association has not been explored in this region. A better understanding of the epidemiologic link could help define effective preventive strategies. We aimed to explore the association of vitamin A deficiency (VAD) with stunting, wasting, and underweight among preschool children in Uganda.

METHOD

We analyzed a population-based, cross-sectional data of 4,765 children aged 6-59 months who participated in 2016 Demographic and Health Surveys conducted in Uganda. We utilized generalized linear mixed-effects models with logit link function, adjusting for potential confounders to estimate associations between VAD and stunting, wasting, and underweight.

RESULTS

The prevalence of VAD was 8.9% (95% CI: 8.1% to 9.6%, n = 424). Twenty-seven percent were stunted (95% CI: 26.1% to 28.6, n = 1302), 4% wasted (95% CI: 3.6% to 4.7%, n = 196), and 17% underweight (95% CI: 16.0% to 18.2%, n = 813). After adjusting for household factors (e.g., wealth index, education and working status of parents, owning land for agriculture, livestock, herds, or farm animals), vitamin A supplementation, and community factors (e.g., population density, crop growing season lengths, place of residence), children with VAD had 43% higher odds of stunted growth than those without VAD (adjusted odds ratio, 1.43 (95% CI: 1.08 to 1.89, p = 0.01). No association was observed between VAD and wasting or underweight.

CONCLUSION

Vitamin A deficiency was associated with higher odds of stunting, and the association was independent of the individual, household, and community-level variables.

An Ethnobotanical Survey of a Dryland Botanical Garden and Its Environs in Kenya: The Mutomo Hill Plant Sanctuary

Mutomo hill plant sanctuary is a ten-hectare piece of land in Kenya listed as a botanical garden under the Botanical Gardens Conservation International, originally established in 1964 with the aim of conserving indigenous flora from destructive anthropogenic activities. This paper presents ethnobotanical documentation of medicinal plants of Mutomo hill plant sanctuary and its environs. An ethnobotanical survey was carried out in Mutomo hill plant sanctuary and its environs with 48 herbalists aged between 32 and 96 years from July 2018 to February 2019 using a semistructured open-ended questionnaire. The plants were collected through random surveys with each herbalist in different ecotypes around the villages and within the Mutomo hill plant sanctuary. The Relative Frequency of Citation (RFC) for each species reported was calculated to determine the plant species frequently collected. In total, 68 different plant species distributed in 28 families and 54 genera were reported. The frequently used plant families were Leguminosae (13 species), Lamiaceae (6 species), and Euphorbiaceae (6 species). Shrubs (37%) and trees (34%) were the dominant growth habits reported. The most cited plant species were Cassia abbreviata Oliv. (RFC = 0.63), Acacia nilotica (L.). Delile (RFC = 0.54), Strychnos heningsii Gilg (RFC = 0.46), and Aloe secundiflora Engl. (RFC = 0.31). Root (19 species) and bark (19 species) were the frequently collected plant parts. Infectious diseases (33) and digestive system disorders (24) were reported to be managed with the majority of the plant species. This study contributes to safeguarding the traditional knowledge on medicinal plants in the study area, which is useful in appreciating and acknowledging the cultural heritage of the Kamba people from the local perspective of Mutomo area in Kenya. It also adds to the knowledge base and documentation of medicinal plants, which is useful information as potential data for drug development.

Ecological inference for infectious disease data, with application to vaccination strategies

Disease surveillance systems provide a rich source of data regarding infectious diseases, aggregated across geographical regions. The analysis of such ecological data is fraught with difficulties, and, unless care and suitable data summaries are available, will lead to biased estimates of individual-level parameters. We consider using surveillance data to study the impacts of vaccination. To catalog the problems of ecological inference, we start with an individual-level model, which contains familiar parameters, and derive an ecologically consistent model for infectious diseases in partially vaccinated populations. We compare with other popular model classes and highlight deficiencies. We explore the properties of the new model through simulation and demonstrate that, under standard assumptions, the ecological model provides less biased estimates. We then fit the new model to data collected on measles outbreaks in Germany from 2005-2007.

Estimating the effect of measles vaccination on child growth using 191 DHS from 65 low- and middle-income countries

BACKGROUND

Childhood vaccinations reduce morbidity and mortality and are highly cost-effective. They may also protect children from malnutrition and lead to improved child growth. Stunting, wasting and underweight are targets used to monitor progress towards the achievement of the sustainable development goals (SDGs).

METHODS

We use data from Demographic and Health Surveys (DHS) covering the period from 1990 to 2017 to estimate the effect of measles vaccination at 12 months of age on stunting, wasting, and underweight. For causal estimation, we use household- and mother-fixed effects, which allows us to compare outcomes across siblings while controlling for all observed and unobserved confounders that are shared by the siblings, such as household social characteristics and home location. In addition, we control for a wide range of sibling-varying confounders, including sex, age, birth order and mother's age at birth, as well as vaccination with diphtheria-tetanus-polio (DPT), as a broad indicator of general likelihood to receive vaccinations.

RESULTS

Our samples include 347,808 individuals in 132 surveys from 59 countries (for stunting), 430,963 individuals in 190 surveys from 65 countries (for wasting), and 353,520 individuals in 130 surveys from 59 countries (for underweight). Measles vaccination is associated with significantly reduced odds of stunting (odds ratio 0.90 [95% CI 0.86-0.94], p < 0.001) and underweight (odds ratio 0.90 [95% CI 0.86-0.95], p < 0.001). The association with wasting is weaker and not statistically significant (odds ratio 0.95 [95% CI 0.89-1.02], p = 0.143). Our results remain robust across several alternative specifications of our regression models.

CONCLUSIONS

Measles vaccination substantially reduces stunting and underweight among children in low- and middle-income countries. Increasing measles coverage from the current low to near-universal levels would provide a large boost to child growth and the attainment of the SDGs.

Sero-Prevalence Surveillance to Predict Vaccine-Preventable Disease Outbreaks; A Lesson from the 2014 Measles Epidemic in Northern Vietnam

Background

During the first half of 2014, a severe outbreak of measles occurred in northern Vietnam, causing 15 033 confirmed cases and 146 deaths.

Methods

To evaluate the population-level seroprevalence of protection against measles in the period before the outbreak, we made use of an existing age-stratified serum bank, collected over the year before the outbreak, between November 2012 and December 2013, from 4 sites across the country (Hanoi, Hue, Dak Lak, and Ho Chi Minh City). Data from the UNICEF’s Multiple Indicator Clustered Surveys (MICS), carried out in Vietnam during the first quarter of 2014, were used to assess the vaccine coverage in 6 ecological regions of Vietnam.

Results

Results revealed a large discrepancy between levels of protection, as estimated from the serology and vaccine coverage estimated by UNICEF’s MICS. Variation in seroprevalence across locations and age groups corresponded with reported numbers of measles cases, most of which were among the 0–2-year-old age group and in the northern part of the country.

Conclusions

Our study presents a strong case in favor of a serosurveillance sentinel network that could be used to proactively tune vaccination policies and other public health interventions.

Under-five mortality in the Rongo Sub-County of Migori County, Kenya: Experience of the Lwala Community Alliance 2007-2017 with evidence from a cross-sectional survey

Introduction

Childhood mortality remains a pressing problem in rural Kenya, and reducing under-five deaths is a key target of the Sustainable Development Goals. We aim to describe the reduction in under-five mortality in a rural Kenyan community served by the Lwala Community Alliance and factors associated with under-five mortality in this community.

Methods

A cross-sectional survey containing a complete birth history was administered to a representative sample of the catchment area of the Lwala Community Alliance. Survival analysis techniques were used to describe temporal trends and risk factors related to under-five mortality.

Results

1,362 children were included in the study, and 91 children died before the fifth birthday. The most common causes of death among children under five were malaria (19%), respiratory infection (13%), and anemia (11%). The under-five mortality rate was 104.8 per 1,000 live births from 1999 to 2006 and 53.0 per 1,000 after the founding of the Lwala Community Alliance in 2007. Factors associated with under-five mortality included year of birth (HR 0.931; 95% CI: 0.877, 0.988; p = 0.019), multiple-gestation pregnancy (HR 6.201; 95% CI: 2.073, 18.555; p < 0.001), and birth in the long rain season (HR 1.981; 95% CI: 1.350, 2.907; p < 0.001). Birth spacing greater than 18 months was negatively associated with under-five mortality (HR 0.345; 95% CI: 0.203, 0.587; p < 0.001).

Conclusions

There was a significant decrease in under-five mortality before and after the presence of the Lwala Community Alliance. Multiple-gestation pregnancies, birth season, and short birth spacing were associated with under-five mortality and provide possible targets to further reduce mortality in the region. This provides both hyper-local data necessary for implementation efforts and generalizable data and sampling methods that may be useful for other implementing organizations in sub-Saharan Africa.

Role of Vitamin A in the Immune System

Vitamin A (VitA) is a micronutrient that is crucial for maintaining vision, promoting growth and development, and protecting epithelium and mucus integrity in the body. VitA is known as an anti-inflammation vitamin because of its critical role in enhancing immune function. VitA is involved in the development of the immune system and plays regulatory roles in cellular immune responses and humoral immune processes. VitA has demonstrated a therapeutic effect in the treatment of various infectious diseases. To better understand the relationship between nutrition and the immune system, the authors review recent literature about VitA in immunity research and briefly introduce the clinical application of VitA in the treatment of several infectious diseases.

Epidemiology of measles in the metropolitan setting, Addis Ababa, Ethiopia, 2005-2014: a retrospective descriptive surveillance data analysis

BACKGROUND

Measles is a highly infectious and serious respiratory viral disease which caused by a virus. It is a significant cause of illness and death worldwide. This data analysis was conducted to describe the trend and determine the reporting rate of measles cases in Addis Ababa to make recommendation for the government of the city to strengthening measles control interventions.

METHODS

We obtained and extracted ten years (2005-2014) Addis Ababa city's measles surveillance data from national database. We carried out retrospective descriptive data analysis by time, place and person variables. We calculated cumulative and specific reporting rates by dividing measles cases (lab confirmed, epidemiologically linked and compatible cases) to respective population and multiplying by 100,000. We divided average of ten years measles cases to midyear population and multiplied by 100,000 to calculate annualized reporting rate. We analyzed non-measles febrile rash rate by dividing laboratory negative cases to total population and multiplying by 100,000.

RESULTS

A total of 4203 suspected measles cases were identified. Among them 1154 (27.5%) were laboratory confirmed, 512 (12.2%) were clinically compatible, 52 (1.2%) were epidemiologically linked cases and the rest 2485 (59.1%) were IgM negative for measles which makes total measles cases 1718 (40.9%). Median age was 5 years with 2-18 years interquartile-range. The annualized measles reporting rate was 5.9, which was 40.2 among > 1 year, 11.5 among 1-4 years, 6.0 among 5-14 years, 4.1 among 15-44 years and 0.01 among ≥ 45 years per 100,000 population. Among the total measles cases; 380 (22%) were received at least one dose of measles containing vaccine (MCV) while 415 (24%) cases were not vaccinated and the vaccination status of 923 (54%) cases were not known.

CONCLUSION

Our analysis revealed that the reporting rate was higher among young children than older age group. Among all the patients 22% were received at least one dose of measles vaccine whereas 13% were not vaccinated against measles antigen. Routine immunization should be strengthened to reach all children through well monitored vaccine cold chain management.

Estimating the distribution of morbidity and mortality of childhood diarrhea, measles, and pneumonia by wealth group in low- and middle-income countries

BACKGROUND

Equitable access to vaccines has been suggested as a priority for low- and middle-income countries (LMICs). However, it is unclear whether providing equitable access is enough to ensure health equity. Furthermore, disaggregated data on health outcomes and benefits gained across population subgroups are often unavailable. This paper develops a model to estimate the distribution of childhood disease cases and deaths across socioeconomic groups, and the potential benefits of three vaccine programs in LMICs.

METHODS

For each country and for three diseases (diarrhea, measles, pneumonia), we estimated the distributions of cases and deaths that would occur across wealth quintiles in the absence of any immunization or treatment programs, using both the prevalence and relative risk of a set of risk and prognostic factors. Building on these baseline estimates, we examined what might be the impact of three vaccines (first dose of measles, pneumococcal conjugate, and rotavirus vaccines), under five scenarios based on different sets of quintile-specific immunization coverage and disease treatment utilization rates.

RESULTS

Due to higher prevalence of risk factors among the poor, disproportionately more disease cases and deaths would occur among the two lowest wealth quintiles for all three diseases when vaccines or treatment are unavailable. Country-specific context, including how the baseline risks, immunization coverage, and treatment utilization are currently distributed across quintiles, affects how different policies translate into changes in cases and deaths distribution.

CONCLUSIONS

Our study highlights several factors that would substantially contribute to the unequal distribution of childhood diseases, and finds that merely ensuring equal access to vaccines will not reduce the health outcomes gap across wealth quintiles. Such information can inform policies and planning of programs that aim to improve equitable delivery of healthcare services.

Individual decisions to vaccinate one's child or oneself: A discrete choice experiment rejecting free-riding motives

It is essential for public health to understand what drives people's hesitance towards vaccination. Theoretical models of vaccination decisions are ubiquitous, often incorporating herd immunity, perceptions of vaccine-related side-effects (VRSE) and of vaccine-preventable burden of disease, but with little to no empirical exploration. Herd immunity is a (usually) positive externality where vaccinated individuals influence others' risks by their reduced capability to transmit an infectious disease to them. It is often assumed that (rational) individuals incorporate this externality in their strategic vaccination decision, from which free-riding behavior arises. We performed a Bayesian D-efficient discrete choice experiment in February-March 2017 to study vaccination behavior in 1919 Belgian respondents. Choice sets with vaccine profiles were constructed using six attributes: vaccine effectiveness, VRSE, accessibility (in terms of convenience and reimbursement), vaccine-preventable burden of disease, local (respondents' network of contacts) vaccination coverage, and population (the population at large) vaccination coverage. VRSE and accessibility are the most influential attributes, followed by vaccine effectiveness and burden of disease. Both population and local coverage are less important than the other attributes, but show a significant direct linear relationship with vaccine utility. This supports the existence of peer influence (more incentivized as more and more vaccinate), rather than free-riding on herd immunity. These findings were independent of whether respondents made vaccine choices for themselves or for their child. Around 40% of the respondents indicated accepting vaccination with little or no questioning. These 'acceptors' were less sensitive to changes in the vaccine-preventable burden of disease for their child's vaccination choices (but not for themselves). Public health institutions are critical in stimulating vaccine uptake by making vaccines conveniently available at an affordable price and by communicating pro-actively on perceived VRSEs. The free-riding assumption as a driver of individual vaccine decisions, seems inappropriate, but this observation needs confirming in other populations.

Challenges and Opportunities in Disease Forecasting in Outbreak Settings: A Case Study of Measles in Lola Prefecture, Guinea

We report on and evaluate the process and findings of a real-time modeling exercise in response to an outbreak of measles in Lola prefecture, Guinea, in early 2015 in the wake of the Ebola crisis. Multiple statistical methods for the estimation of the size of the susceptible (i.e., unvaccinated) population were applied to weekly reported measles case data on seven subprefectures throughout Lola. Stochastic compartmental models were used to project future measles incidence in each subprefecture in both an initial and a follow-up iteration of forecasting. Measles susceptibility among 1- to 5-year-olds was estimated to be between 24% and 43% at the beginning of the outbreak. Based on this high baseline susceptibility, initial projections forecasted a large outbreak occurring over approximately 10 weeks and infecting 40 children per 1,000. Subsequent forecasts based on updated data mitigated this initial projection, but still predicted a significant outbreak. A catch-up vaccination campaign took place at the same time as this second forecast and measles cases quickly receded. Of note, case reports used to fit models changed significantly between forecast rounds. Model-based projections of both current population risk and future incidence can help in setting priorities and planning during an outbreak response. A swiftly changing situation on the ground, coupled with data uncertainties and the need to adjust standard analytical approaches to deal with sparse data, presents significant challenges. Appropriate presentation of results as planning scenarios, as well as presentations of uncertainty and two-way communication, is essential to the effective use of modeling studies in outbreak response.

Effect and cost-effectiveness of educating mothers about childhood DPT vaccination on immunisation uptake, knowledge, and perceptions in Uttar Pradesh, India: A randomised controlled trial

BACKGROUND

To assess the effect of health information on immunisation uptake in rural India, we conducted an individually randomised controlled trial of health information messages targeting the mothers of unvaccinated or incompletely vaccinated children through home visits in rural Uttar Pradesh, India.

METHODS AND FINDINGS

The study tested a brief intervention that provided mothers face-to-face with information on the benefits of the tetanus vaccine. Participants were 722 mothers of children aged 0-36 months who had not received 3 doses of diphtheria-pertussis-tetanus (DPT) vaccine (DPT3). Mothers were randomly assigned in a ratio of 1:1:1 to 1 of 3 study arms: mothers in the first treatment group received information framed as a gain (e.g., the child is less likely to get tetanus and more likely to be healthy if vaccinated), mothers in the second treatment group received information framed in terms of a loss (e.g., the child is more likely to get tetanus and suffer ill health if not vaccinated), and the third arm acted as a control group, with no information given to the mother. Surveys were conducted at baseline (September 2015) and after the intervention (April 2016). The primary outcome was the proportion of children who had received DPT3 measured after 7 months of follow-up. The analysis was by intention to treat. A total of 16 (2.2%) participants were lost to follow-up. The coverage of DPT3 was 28% in the control group and 43% in the pooled information groups, giving a risk difference of 15 percentage points (95% CI: 7% to 22%, p < 0.001) and a relative risk of 1.52 (95% CI: 1.2 to 1.9, p < 0.001). The information intervention increased the rate of measles vaccination by 22 percentage points (risk difference: 22%, 95% CI: 14% to 30%, p < 0.001; relative risk: 1.53, 95% CI: 1.29 to 1.80) and the rate of full immunisation by 14 percentage points (risk difference: 14%, 95% CI: 8% to 21%, p < 0.001; relative risk: 1.72, 95% CI: 1.29 to 2.29). It had a large positive effect on knowledge of the causes, symptoms, and prevention of tetanus but no effect on perceptions of vaccine efficacy. There was no difference in the proportion of children with DPT3 between the group that received information framed as a loss and the group that received information framed as a gain (risk difference: 4%, 95% CI: -5% to 13%; p = 0.352; relative risk: 1.11, 95% CI: 0.90 to 1.36). The cost per disability-adjusted life year averted of providing information was US$186, making the intervention highly cost-effective with respect to the WHO-recommended threshold of once the gross domestic product per capita (US$793 in the case of Uttar Pradesh). Key study limitations include the modest sample size for this trial, limiting power to detect small differences in the framing of information, and the potential for contamination among households.

CONCLUSIONS

Providing mothers of unvaccinated/incompletely vaccinated children with information on tetanus and the benefits of DPT vaccination substantially increased immunisation coverage and was highly cost-effective. The framing of the health information message did not appear to matter.

TRIAL REGISTRATION

The trial is registered with ISRCTN, number ISRCTN84560580.

Factors contributing to measles transmission during an outbreak in Kamwenge District, Western Uganda, April to August 2015

Background

In April 2015, Kamwenge District, western Uganda reported a measles outbreak. We investigated the outbreak to identify potential exposures that facilitated measles transmission, assess vaccine effectiveness (VE) and vaccination coverage (VC), and recommend prevention and control measures.

Methods

For this investigation, a probable case was defined as onset of fever and generalized maculopapular rash, plus ≥1 of the following symptoms: Coryza, conjunctivitis, or cough. A confirmed case was defined as a probable case plus identification of measles-specific IgM in serum. For case-finding, we reviewed patients’ medical records and conducted in-home patient examination. In a case-control study, we compared exposures of case-patients and controls matched by age and village of residence. For children aged 9 m-5y, we estimated VC using the percent of children among the controls who had been vaccinated against measles, and calculated VE using the formula, VE = 1 - OR_M-H, where OR_M-H was the Mantel-Haenszel odds ratio associated with having a measles vaccination history.

Results

We identified 213 probable cases with onset between April and August, 2015. Of 23 blood specimens collected, 78% were positive for measles-specific IgM. Measles attack rate was highest in the youngest age-group, 0-5y (13/10,000), and decreased as age increased. The epidemic curve indicated sustained propagation in the community. Of the 50 case-patients and 200 controls, 42% of case-patients and 12% of controls visited health centers during their likely exposure period (OR_M-H = 6.1; 95% CI = 2.7–14). Among children aged 9 m-5y, VE was estimated at 70% (95% CI: 24–88%), and VC at 75% (95% CI: 67–83%). Excessive crowding was observed at all health centers; no patient triage-system existed.

Conclusions

The spread of measles during this outbreak was facilitated by patient mixing at crowded health centers, suboptimal VE and inadequate VC. We recommended emergency immunization campaign targeting children <5y in the affected sub-counties, as well as triaging and isolation of febrile or rash patients visiting health centers.

Spatial clustering of measles vaccination coverage among children in sub-Saharan Africa

Background

During the past two decades, vaccination programs have greatly reduced global morbidity and mortality due to measles, but recently this progress has stalled. Even in countries that report high vaccination coverage rates, transmission has continued, particularly in spatially clustered subpopulations with low vaccination coverage.

Methods

We examined the spatial heterogeneity of measles vaccination coverage among children aged 12–23 months in ten Sub-Saharan African countries. We used the Anselin Local Moran’s I to estimate clustering of vaccination coverage based on data from Demographic and Health Surveys conducted between 2008 and 2013. We also examined the role of sociodemographic factors to explain clustering of low vaccination.

Results

We detected 477 spatial clusters with low vaccination coverage, many of which were located in countries with relatively high nationwide vaccination coverage rates such as Zambia and Malawi. We also found clusters in border areas with transient populations. Clustering of low vaccination coverage was related to low health education and limited access to healthcare.

Conclusions

Systematically monitoring clustered populations with low vaccination coverage can inform supplemental immunization activities and strengthen elimination programs. Metrics of spatial heterogeneity should be used routinely to determine the success of immunization programs and the risk of disease persistence.

Impact of measles supplementary immunization activities on reaching children missed by routine programs

BACKGROUND

Measles supplementary immunization activities (SIAs) are vaccination campaigns that supplement routine vaccination programs with a recommended second dose opportunity to children of different ages regardless of their previous history of measles vaccination. They are conducted every 2-4 years and over a few weeks in many low- and middle-income countries. While SIAs have high vaccination coverage, it is unclear whether they reach the children who miss their routine measles vaccine dose. Determining who is reached by SIAs is vital to understanding their effectiveness, as well as measure progress towards measles control.

METHODS

We examined SIAs in low- and middle-income countries from 2000 to 2014 using data from the Demographic and Health Surveys. Conditional on a child's routine measles vaccination status, we examined whether children participated in the most recent measles SIA.

RESULTS

The average proportion of zero-dose children (no previous routine measles vaccination defined as no vaccination date before the SIA) reached by SIAs across 14 countries was 66%, ranging from 28% in São Tomé and Príncipe to 91% in Nigeria. However, when also including all children with routine measles vaccination data, this proportion decreased to 12% and to 58% when imputing data for children with vaccination reported by the mother and vaccination marks on the vaccination card across countries. Overall, the proportions of zero-dose children reached by SIAs declined with increasing household wealth.

CONCLUSIONS

Some countries appeared to reach a higher proportion of zero-dose children using SIAs than others, with proportions reached varying according to the definition of measles vaccination (e.g., vaccination dates on the vaccination card, vaccination marks on the vaccination card, and/or self-reported data). This suggests that some countries could improve their targeting of SIAs to children who miss other measles vaccine opportunities. Across all countries, SIAs played an important role in reaching children from poor households.

Identify the susceptibility profile to measles in the general population: Serological survey of measles antibodies in Shaanxi province, China, in 2016

The reported coverage with two doses of the measles vaccine (MCV) in Shaanxi Province, China, is greater than 95%, but the measles incidence over the whole province remains high. Cross-sectional serological surveys of measles antibodies in Shaanxi Province were conducted in 2016 to assess the population's immunity. The measles IgG levels were measured in serum samples using ELISA. The geometric means concentration (GMC) levels and seroprevalence rates with 95% CIs were calculated by region, gender, and age. A total of 3574 serum samples were collected from participants aged from 2 months to 49 years. The GMC of measles antibodies was 471.3 mIU/ml (95% CI: 445.9-498.2 mIU/ml), and the seroprevalence was only 85.9% (95% CI: 84.8-87.1%). A significant difference in the GMC (P < .05) but not the seroprevalence (P > .05) was observed among the 3 regions. The report measles incidences were high in individuals aged 0-7 months (33.2/100 000) and 8-17 months (26.8/100 000). Although both measles immunity (90.7%) and MCV coverage (89.7%) were low in children aged 8-17 months, the measles seroprevalence in adults was high at greater than 90%. These results revealed that further actions may be taken to increase vaccination coverage in children aged 8 months to 5 years over the whole province and teenagers in the south region. In particular, timely administration of the first MCV dose should be emphasized to prevent measles epidemics in children aged 8-17 months. Vaccination strategies may be varied by age and region.

Postneonatal mortality impacts following grants from the Gavi Vaccine Alliance: an econometric analysis from 2000 to 2014

We completed a retrospective multivariate panel study to evaluate the effect of Gavi Vaccine Alliance grants on vaccine-preventable disease (VPD) postneonatal mortality. We separately tested a composite VPD mortality rate and five vaccine-preventable mortality rates: pertussis, meningitis, measles, diarrhea, and pneumonia (lower-respiratory infection) as dependent variables. All 77 countries eligible for Gavi assistance from 2000 to 2014 were included in the study. To isolate the effect of Gavi funding in our primary model, we controlled for known and likely predictors of child mortality. We found evidence that, among other factors, Gavi investment, antenatal care access, and girls' primary education are important elements to reduce vaccine-preventable mortality rates. For every $1 per capita invested by the Gavi Vaccine Alliance, there are statistically significant effects decreasing the VPD postneonatal mortality rate by 1.848 per 1000 live births. We also found Gavi investments to be significantly associated with reductions in three VPD-specific rates: pertussis, meningitis, and pneumonia. We conclude that Gavi investments in developing country immunization programs have measurably contributed to reductions in postneonatal VPD mortality rates.

Impact of Childhood Malnutrition on Host Defense and Infection

The global impact of childhood malnutrition is staggering. The synergism between malnutrition and infection contributes substantially to childhood morbidity and mortality. Anthropometric indicators of malnutrition are associated with the increased risk and severity of infections caused by many pathogens, including viruses, bacteria, protozoa, and helminths. Since childhood malnutrition commonly involves the inadequate intake of protein and calories, with superimposed micronutrient deficiencies, the causal factors involved in impaired host defense are usually not defined. This review focuses on literature related to impaired host defense and the risk of infection in primary childhood malnutrition. Particular attention is given to longitudinal and prospective cohort human studies and studies of experimental animal models that address causal, mechanistic relationships between malnutrition and host defense. Protein and micronutrient deficiencies impact the hematopoietic and lymphoid organs and compromise both innate and adaptive immune functions. Malnutrition-related changes in intestinal microbiota contribute to growth faltering and dysregulated inflammation and immune function. Although substantial progress has been made in understanding the malnutrition-infection synergism, critical gaps in our understanding remain. We highlight the need for mechanistic studies that can lead to targeted interventions to improve host defense and reduce the morbidity and mortality of infectious diseases in this vulnerable population.

Characterizing measles transmission in India: a dynamic modeling study using verbal autopsy data

BACKGROUND

Decreasing trends in measles mortality have been reported in recent years. However, such estimates of measles mortality have depended heavily on assumed regional measles case fatality risks (CFRs) and made little use of mortality data from low- and middle-income countries in general and India, the country with the highest measles burden globally, in particular.

METHODS

We constructed a dynamic model of measles transmission in India with parameters that were empirically inferred using spectral analysis from a time series of measles mortality extracted from the Million Death Study, an ongoing longitudinal study recording deaths across 2.4 million Indian households and attributing causes of death using verbal autopsy. The model was then used to estimate the measles CFR, the number of measles deaths, and the impact of vaccination in 2000-2015 among under-five children in India and in the states of Bihar and Uttar Pradesh (UP), two states with large populations and the highest numbers of measles deaths in India.

RESULTS

We obtained the following estimated CFRs among under-five children for the year 2005: 0.63% (95% confidence interval (CI): 0.40-1.00%) for India as a whole, 0.62% (0.38-1.00%) for Bihar, and 1.19% (0.80-1.75%) for UP. During 2000-2015, we estimated that 607,000 (95% CI: 383,000-958,000) under-five deaths attributed to measles occurred in India as a whole. If no routine vaccination or supplemental immunization activities had occurred from 2000 to 2015, an additional 1.6 (1.0-2.6) million deaths for under-five children would have occurred across India.

CONCLUSIONS

We developed a data- and model-driven estimation of the historical measles dynamics, CFR, and vaccination impact in India, extracting the periodicity of epidemics using spectral and coherence analysis, which allowed us to infer key parameters driving measles transmission dynamics and mortality.

Promoting Early Child Development With Interventions in Health and Nutrition: A Systematic Review

CONTEXT

Although effective health and nutrition interventions for reducing child mortality and morbidity exist, direct evidence of effects on cognitive, motor, and psychosocial development is lacking.

OBJECTIVE

To review existing evidence for health and nutrition interventions affecting direct measures of (and pathways to) early child development.

DATA SOURCES

Reviews and recent overviews of interventions across the continuum of care and component studies.

STUDY SELECTION

We selected systematic reviews detailing the effectiveness of health or nutrition interventions that have plausible links to child development and/or contain direct measures of cognitive, motor, and psychosocial development.

DATA EXTRACTION

A team of reviewers independently extracted data and assessed their quality.

RESULTS

Sixty systematic reviews contained the outcomes of interest. Various interventions reduced morbidity and improved child growth, but few had direct measures of child development. Of particular benefit were food and micronutrient supplementation for mothers to reduce the risk of small for gestational age and iodine deficiency, strategies to reduce iron deficiency anemia in infancy, and early neonatal care (appropriate resuscitation, delayed cord clamping, and Kangaroo Mother Care). Neuroprotective interventions for imminent preterm birth showed the largest effect sizes (antenatal corticosteroids for developmental delay: risk ratio 0.49, 95% confidence interval 0.24 to 1.00; magnesium sulfate for gross motor dysfunction: risk ratio 0.61, 95% confidence interval 0.44 to 0.85).

LIMITATIONS

Given the focus on high-quality studies captured in leading systematic reviews, only effects reported within studies included in systematic reviews were captured.

CONCLUSIONS

These findings should guide the prioritization and scale-up of interventions within critical periods of early infancy and childhood, and encourage research into their implementation at scale.

Biological challenges to effective vaccines in the developing world

The reason for holding a meeting to discuss biological challenges to vaccines is simple: not all vaccines work equally well in all settings. This special issue reviews the performance of vaccines in challenging environments, summarizes current thinking on the reasons why vaccines underperform and considers what approaches are necessary to understand the heterogeneity in responses and to improve vaccine immunogenicity and efficacy.

Microneedle patches for vaccination in developing countries

Millions of people die of infectious diseases each year, mostly in developing countries, which could largely be prevented by the use of vaccines. While immunization rates have risen since the introduction of the Expanded Program on Immunization (EPI), there remain major challenges to more effective vaccination in developing countries. As a possible solution, microneedle patches containing an array of micron-sized needles on an adhesive backing have been developed to be used for vaccine delivery to the skin. These microneedle patches can be easily and painlessly applied by pressing against the skin and, in some designs, do not leave behind sharps waste. The patches are single-dose, do not require reconstitution, are easy to administer, have reduced size to simplify storage, transportation and waste disposal, and offer the possibility of improved vaccine immunogenicity, dose sparing and thermostability. This review summarizes vaccination challenges in developing countries and discusses advantages that microneedle patches offer for vaccination to address these challenges. We conclude that microneedle patches offer a powerful new technology that can enable more effective vaccination in developing countries.