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Vaccine Jun 2024Measles remains a critical public health concern causing significant morbidity and mortality globally. Despite the success of measles vaccination programs, challenges...
INTRODUCTION
Measles remains a critical public health concern causing significant morbidity and mortality globally. Despite the success of measles vaccination programs, challenges persist, particularly in India. This study investigates dose-wise measles vaccination coverage and explores gaps in immunization focusing on zero-dose, one-dose, and two-dose coverage among children aged 24-35 months.
DATA SOURCES AND METHODOLOGY
The National Family Health Survey 2019-21 (NFHS-5) served as the data source and the study analyzed information from 43,864 children aged 24-35 months. Sociodemographic variables such as birth order, wealth quintile, gender, social group, religion, residence, mother education, delivery-related factors, and media exposure were considered. Statistical analysis involved weighted estimates, chi-square tests, and multivariate multinomial logistic regression.
RESULTS
The study revealed that challenges persist in achieving optimal measles vaccination coverage. Analysis by sociodemographic factors highlighted disparities in coverage, with variations in zero dose prevalence across states and districts. The percentage of zero-dose children was significantly higher, with 11.5% of children in India remaining to receive any measles vaccination. Factors influencing vaccine coverage include birth order, age, wealth quintile, social group, religion, residence, maternal education, place of delivery, media exposure, and mode of delivery. The findings from the spatial analysis show the clustering of zero-dose children is high in the northeastern states of India.
DISCUSSION
Measles zero-dose children pose a significant obstacle to achieving elimination goals. Spatial analysis identifies clusters of unvaccinated populations guiding targeted interventions. The study aligns with global initiatives such as the Immunization Agenda 2030 emphasizing equitable vaccine access and discusses how India can tailor its strategies to achieve the goal. Lessons from polio eradication efforts inform strategies for measles elimination, stressing the importance of high-quality data and surveillance. The study underscores the urgency of addressing last-mile measles vaccination gaps in India. Spatially targeted interventions informed by sociodemographic factors can enhance immunization coverage. Achieving measles elimination requires sustained efforts and leveraging lessons from successful vaccination campaigns. The study findings have the potential to contribute to informed decision-making, supporting India's roadmap for the measles and rubella elimination goal.
Topics: Humans; India; Vaccination Coverage; Measles; Measles Vaccine; Female; Male; Child, Preschool; Immunization Programs; Vaccination; Disease Eradication
PubMed: 38704248
DOI: 10.1016/j.vaccine.2024.04.075 -
Lancet (London, England) May 2024Microneedle patches (MNPs) have been ranked as the highest global priority innovation for overcoming immunisation barriers in low-income and middle-income countries.... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Microneedle patches (MNPs) have been ranked as the highest global priority innovation for overcoming immunisation barriers in low-income and middle-income countries. This trial aimed to provide the first data on the tolerability, safety, and immunogenicity of a measles and rubella vaccine (MRV)-MNP in children.
METHODS
This single-centre, phase 1/2, double-blind, double-dummy, randomised, active-controlled, age de-escalation trial was conducted in The Gambia. To be eligible, all participants had to be healthy according to prespecified criteria, aged 18-40 years for the adult cohort, 15-18 months for toddlers, or 9-10 months for infants, and to be available for visits throughout the follow-up period. The three age cohorts were randomly assigned in a 2:1 ratio (adults) or 1:1 ratio (toddlers and infants) to receive either an MRV-MNP (Micron Biomedical, Atlanta, GA, USA) and a placebo (0·9% sodium chloride) subcutaneous injection, or a placebo-MNP and an MRV subcutaneous injection (MRV-SC; Serum Institute of India, Pune, India). Unmasked staff ransomly assigned the participants using an online application, and they prepared visually identical preparations of the MRV-MNP or placebo-MNP and MRV-SC or placebo-SC, but were not involved in collecting endpoint data. Staff administering the study interventions, participants, parents, and study staff assessing trial endpoints were masked to treatment allocation. The safety population consists of all vaccinated participants, and analysis was conducted according to route of MRV administration, irrespective of subsequent protocol deviations. The immunogenicity population consisted of all vaccinated participants who had a baseline and day 42 visit result available, and who had no protocol deviations considered to substantially affect the immunogenicity endpoints. Solicited local and systemic adverse events were collected for 14 days following vaccination. Unsolicited adverse events were collected to day 180. Age de-escalation between cohorts was based on the review of the safety data to day 14 by an independent data monitoring committee. Serum neutralising antibodies to measles and rubella were measured at baseline, day 42, and day 180. Analysis was descriptive and included safety events, seroprotection and seroconversion rates, and geometric mean antibody concentrations. The trial was registered with the Pan African Clinical Trials Registry PACTR202008836432905, and is complete.
FINDINGS
Recruitment took place between May 18, 2021, and May 27, 2022. 45 adults, 120 toddlers, and 120 infants were randomly allocated and vaccinated. There were no safety concerns in the first 14 days following vaccination in either adults or toddlers, and age de-escalation proceeded accordingly. In infants, 93% (52/56; 95% CI 83·0-97·2) seroconverted to measles and 100% (58/58; 93·8-100) seroconverted to rubella following MRV-MNP administration, while 90% (52/58; 79·2-95·2) and 100% (59/59; 93·9-100) seroconverted to measles and rubella respectively, following MRV-SC. Induration at the MRV-MNP application site was the most frequent local reaction occurring in 46 (77%) of 60 toddlers and 39 (65%) of 60 infants. Related unsolicited adverse events, most commonly discolouration at the application site, were reported in 35 (58%) of 60 toddlers and 57 (95%) of 60 infants that had received the MRV-MNP. All local reactions were mild. There were no related severe or serious adverse events.
INTERPRETATION
The safety and immunogenicity data support the accelerated development of the MRV-MNP.
FUNDING
Bill & Melinda Gates Foundation.
Topics: Humans; Double-Blind Method; Gambia; Female; Male; Rubella Vaccine; Infant; Measles Vaccine; Adult; Adolescent; Rubella; Young Adult; Measles; Needles; Antibodies, Viral
PubMed: 38697170
DOI: 10.1016/S0140-6736(24)00532-4 -
Frontiers in Public Health 2024Measles continues to be a public health challenge in Ethiopia. Rumors of suspected measles were notified on April 8, 2023 from Tocha district. We conducted an assessment...
BACKGROUND
Measles continues to be a public health challenge in Ethiopia. Rumors of suspected measles were notified on April 8, 2023 from Tocha district. We conducted an assessment to describe measles outbreak and determine risk factors for measles infection in the Tocha district of the Dawuro zone, Southwest Ethiopia.
METHODS
We conducted a 1:2 unmatched case-control studies from April to May 2023. We took all 147 cases registered on line list for descriptive analyses. We used a total of 74 randomly selected cases and 147 controls for case-control part. Any person in Tocha district with laboratory-confirmed measles IgM antibody; or any suspected person epidemiologically linked to confirmed measles cases from March 23 to April 26 2023, were included in the case. Neighborhood who did not fulfill this standard case definition were included in controls. Data were collected using standardized questionnaires deployed on Kobo Collect. Descriptive analyses were conducted using Epi info version 7.2.5.0. The analyses were performed using Statistical Package for Social Science (SPSS) version 26. Binary logistic regression analyses were utilized to select candidate variables. We conducted multiple logistic regression analysis to identify determinants of measles infection at a value ≤0.05 with 95% confidence interval.
RESULTS
The overall attack rate of 22.64/10,000 for general population and 104.59/10,000 among under-five children were attributed to the outbreak with a case fatality rate of 2.72%. Vaccine coverage in the last year and this year were 73.52 and 53.88%, respectively, while vaccine effectiveness in the district was 79%. Poor house ventilation (AOR = 3.540, 95% CI: 1.663-7.535) and having contact history with the case (AOR = 2.528, 95% CI: 1.180-4.557) were positively related to measles infection while being previously vaccinated for measles (AOR = 0.209, 95% CI: 0.180-4.577) reduce risk of measles infections.
CONCLUSION
The highest attack rate was observed among children under 5 years of age, with a case fatality rate of 2.72%. Vaccination coverage was less than what expected to develop herd immunity. Strategies to increase vaccination coverage and strengthening surveillance systems for rumor identification and early responses to prevent person to person transmission are recommended.
Topics: Humans; Measles; Ethiopia; Disease Outbreaks; Case-Control Studies; Male; Female; Child, Preschool; Adolescent; Child; Risk Factors; Infant; Adult; Young Adult; Measles Vaccine; Surveys and Questionnaires
PubMed: 38689775
DOI: 10.3389/fpubh.2024.1331798 -
Revista Panamericana de Salud Publica =... 2024To evaluate immunization coverage and dropout rates of the measles, mumps, and rubella vaccine across Brazilian regions.
[Space-time heterogeneity of measles, mumps, and rubella vaccination indicators in children from BrazilHeterogeneidad espaciotemporal de los indicadores de inmunización con la vacuna triple viral en la población infantil de Brasil].
OBJECTIVE
To evaluate immunization coverage and dropout rates of the measles, mumps, and rubella vaccine across Brazilian regions.
METHODS
This ecological study employing a space-time approach used data from the National Immunization Program (PNI) and the Live Births Information System (SINASC). We estimated the annual variation (2014 to 2021) in immunization coverage and dropout rate of the measles, mumps, and rubella vaccine in children aged 12 and 15 months in the 5 570 Brazilian municipalities. Statistical analysis was conducted for the municipalities contained in each Brazilian region using the space-time scan technique, considering the Poisson probabilistic model and the hypothesis that municipalities with lower immunization coverage or high dropout rates would form space-time clusters.
RESULTS
From 2014 to 2021, 38.3% and 12.9% of municipalities achieved a coverage ≥ 95.0% in the first and second doses respectively; 53.6% of municipalities had a high dropout rate (20.0% to 49.9%) and 37.2% had a very high dropout rate. The Northeast region had primary clusters for low coverage of the first (2018 to 2021) and second vaccine doses (2020 to 2021) with higher relative risks (RR) compared to other primary clusters. The RR for high dropout rate was elevated in all Brazilian regions (1.57 to 26.23).
CONCLUSIONS
In some Brazilian regions, the dropout rate has been high since 2014, signaling a risk of measles resurgence. In turn, space-time analysis indicated lower vaccination coverage in 2020, suggesting the influence of the COVID-19 pandemic.
PubMed: 38686134
DOI: 10.26633/RPSP.2024.34 -
PLOS Global Public Health 2024Community-based serological studies are increasingly relied upon to measure disease burden, identify population immunity gaps, and guide control and elimination...
Who is missed in a community-based survey: Assessment and implications of biases due to incomplete sampling frame in a community-based serosurvey, Choma and Ndola Districts, Zambia, 2022.
Community-based serological studies are increasingly relied upon to measure disease burden, identify population immunity gaps, and guide control and elimination strategies; however, there is little understanding of the potential for and impact of sampling biases on outcomes of interest. As part of efforts to quantify measles immunity gaps in Zambia, a community-based serological survey using stratified multi-stage cluster sampling approach was conducted in Ndola and Choma districts in May-June 2022, enrolling 1245 individuals. We carried out a follow-up study among individuals missed from the sampling frame of the serosurvey in July-August 2022, enrolling 672 individuals. We assessed the potential for and impact of biases in the community-based serosurvey by i) estimating differences in characteristics of households and individuals included and excluded (77% vs 23% of households) from the sampling frame of the serosurvey and ii) evaluating the magnitude these differences make on healthcare-seeking behavior, vaccination coverage, and measles seroprevalence. We found that missed households were 20% smaller and 25% less likely to have children. Missed individuals resided in less wealthy households, had different distributions of sex and occupation, and were more likely to seek care at health facilities. Despite these differences, simulating a survey in which missed households were included in the sampling frame resulted in less than a 5% estimated bias in these outcomes. Although community-based studies are upheld as the gold standard study design in assessing immunity gaps and underlying community health characteristics, these findings underscore the fact that sampling biases can impact the results of even well-conducted community-based surveys. Results from these studies should be interpreted in the context of the study methodology and challenges faced during implementation, which include shortcomings in establishing accurate and up-to-date sampling frames. Failure to account for these shortcomings may result in biased estimates and detrimental effects on decision-making.
PubMed: 38683820
DOI: 10.1371/journal.pgph.0003072 -
Viruses Apr 2024As SARS-CoV-2 continues to evolve and COVID-19 cases rapidly increase among children and adults, there is an urgent need for a safe and effective vaccine that can elicit...
As SARS-CoV-2 continues to evolve and COVID-19 cases rapidly increase among children and adults, there is an urgent need for a safe and effective vaccine that can elicit systemic and mucosal humoral immunity to limit the emergence of new variants. Using the Chinese Hu191 measles virus (MeV-hu191) vaccine strain as a backbone, we developed MeV chimeras stably expressing the prefusion forms of either membrane-anchored, full-length spike (rMeV-preFS), or its soluble secreted spike trimers with the help of the SP-D trimerization tag (rMeV-S+SPD) of SARS-CoV-2 Omicron BA.2. The two vaccine candidates were administrated in golden Syrian hamsters through the intranasal or subcutaneous routes to determine the optimal immunization route for challenge. The intranasal delivery of rMeV-S+SPD induced a more robust mucosal IgA antibody response than the subcutaneous route. The mucosal IgA antibody induced by rMeV-preFS through the intranasal routine was slightly higher than the subcutaneous route, but there was no significant difference. The rMeV-preFS vaccine stimulated higher mucosal IgA than the rMeV-S+SPD vaccine through intranasal or subcutaneous administration. In hamsters, intranasal administration of the rMeV-preFS vaccine elicited high levels of NAbs, protecting against the SARS-CoV-2 Omicron BA.2 variant challenge by reducing virus loads and diminishing pathological changes in vaccinated animals. Encouragingly, sera collected from the rMeV-preFS group consistently showed robust and significantly high neutralizing titers against the latest variant XBB.1.16. These data suggest that rMeV-preFS is a highly promising COVID-19 candidate vaccine that has great potential to be developed into bivalent vaccines (MeV/SARS-CoV-2).
Topics: Animals; Spike Glycoprotein, Coronavirus; SARS-CoV-2; Antibodies, Viral; Immunity, Mucosal; Antibodies, Neutralizing; Immunity, Humoral; COVID-19; COVID-19 Vaccines; Measles virus; Cricetinae; Immunoglobulin A; Humans; Administration, Intranasal; Mesocricetus; Female
PubMed: 38675901
DOI: 10.3390/v16040559 -
Vaccines Apr 2024Measles, mumps, rubella (MMR), and varicella incidence rates have increased due to the delayed vaccination schedules of children secondary to the COVID-19 pandemic.... (Review)
Review
Measles, mumps, rubella (MMR), and varicella incidence rates have increased due to the delayed vaccination schedules of children secondary to the COVID-19 pandemic. Decreased herd immunity creates a risk for immunocompetent children and immunocompromised individuals in the community. Historically, live-attenuated vaccines (MMR and varicella) were recommended before solid organ transplants. The amount of time before transplant when this is appropriate is often debated, as is the utility of vaccine titers. MMR and varicella vaccines previously were not recommended in immunocompromised patients post-solid organ transplant due to the undue risk of transmission and posed infection risk. The new literature on live-attenuated vaccines in post-transplant pediatric patients provides more insight into the vaccines' safety and efficacy. The present article aims to provide guidance on live-attenuated vaccines (MMR and varicella) in the pre-transplant and post-operative solid organ transplant phases of care in pediatric patients.
PubMed: 38675758
DOI: 10.3390/vaccines12040376 -
Diseases (Basel, Switzerland) Apr 2024The impact of outbreak response immunization (ORI) can be estimated by comparing observed outcomes to modelled counterfactual scenarios without ORI, but the most...
The impact of outbreak response immunization (ORI) can be estimated by comparing observed outcomes to modelled counterfactual scenarios without ORI, but the most appropriate metrics depend on stakeholder needs and data availability. This study developed a framework for using mathematical models to assess the impact of ORI for vaccine-preventable diseases. Framework development involved (1) the assessment of impact metrics based on stakeholder interviews and literature reviews determining data availability and capacity to capture as model outcomes; (2) mapping investment in ORI elements to model parameters to define scenarios; (3) developing a system for engaging stakeholders and formulating model questions, performing analyses, and interpreting results; and (4) example applications for different settings and pathogens. The metrics identified as most useful were health impacts, economic impacts, and the risk of severe outbreaks. Scenario categories included investment in the response scale, response speed, and vaccine targeting. The framework defines four phases: (1) problem framing and data sourcing (identification of stakeholder needs, metrics, and scenarios); (2) model choice; (3) model implementation; and (4) interpretation and communication. The use of the framework is demonstrated by application to two outbreaks, measles in Papua New Guinea and Ebola in the Democratic Republic of the Congo. The framework is a systematic way to engage with stakeholders and ensure that an analysis is fit for purpose, makes the best use of available data, and uses suitable modelling methodology.
PubMed: 38667531
DOI: 10.3390/diseases12040073 -
Euro Surveillance : Bulletin Europeen... Apr 2024In January 2024, a child was diagnosed with measles in a paediatric hospital in Lisbon. Of 123 contacts, 39 (32%) were not fully immunised, presenting a risk for a...
In January 2024, a child was diagnosed with measles in a paediatric hospital in Lisbon. Of 123 contacts, 39 (32%) were not fully immunised, presenting a risk for a potential outbreak. The public health unit initiated control measures and identified challenges during the response, such as the lack of interoperability between information systems and accessing vaccination records. The lessons learned prompted changes to national contact tracing procedures for measles, further strengthening Portugal's preparedness.
Topics: Humans; Measles; Contact Tracing; Portugal; Hospitals, Pediatric; Disease Outbreaks; Male; Child; Child, Preschool; Female; Public Health; Vaccination; Infant; Adolescent
PubMed: 38666402
DOI: 10.2807/1560-7917.ES.2024.29.17.240022 -
EClinicalMedicine Jun 2024A number of countries including the UK are currently experiencing large outbreaks of measles affecting mainly young children but also adolescents and young adults. Women... (Review)
Review
A number of countries including the UK are currently experiencing large outbreaks of measles affecting mainly young children but also adolescents and young adults. Women of childbearing age are a particular group of concern because the 1988 Wakefield Lancet paper, which falsely asserted a connection between the MMR vaccine and autism, was associated with a large and sharp decline in childhood MMR uptake over several years. This has left large cohorts of non-immune adolescents and young adults (born between 1998 and 2004), including young women who are now of childbearing age and remain susceptible to measles as well as rubella. Pregnant mothers are at higher risk of serious complications, such as pneumonia, with adverse pregnancy complications including fetal loss, premature birth, and neonatal death. Measles infection may also result in subacute sclerosing panencephalitis (SSPE), a very rare but very severe and invariably fatal neurodegenerative complication that typically manifests many years after acute measles infection but can have a short-onset latency with a fulminant course in pregnant women. Here, we summarise the epidemiology of measles infection, factors associated with the current measles outbreaks, as well as the risks and outcomes of measles, including SSPE, in pregnancy. We propose an algorithm for clinical management of measles infection in pregnancy. We also highlight the importance of early liaison with local health protection teams for risk assessment, diagnosis and management of suspected measles in pregnancy and close contacts as well as susceptible pregnant women exposed to a person with measles in the community.
PubMed: 38666235
DOI: 10.1016/j.eclinm.2024.102594