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1.
Lancet ; 403(10441): 2307-2316, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38705159

RESUMEN

BACKGROUND: WHO, as requested by its member states, launched the Expanded Programme on Immunization (EPI) in 1974 to make life-saving vaccines available to all globally. To mark the 50-year anniversary of EPI, we sought to quantify the public health impact of vaccination globally since the programme's inception. METHODS: In this modelling study, we used a suite of mathematical and statistical models to estimate the global and regional public health impact of 50 years of vaccination against 14 pathogens in EPI. For the modelled pathogens, we considered coverage of all routine and supplementary vaccines delivered since 1974 and estimated the mortality and morbidity averted for each age cohort relative to a hypothetical scenario of no historical vaccination. We then used these modelled outcomes to estimate the contribution of vaccination to globally declining infant and child mortality rates over this period. FINDINGS: Since 1974, vaccination has averted 154 million deaths, including 146 million among children younger than 5 years of whom 101 million were infants younger than 1 year. For every death averted, 66 years of full health were gained on average, translating to 10·2 billion years of full health gained. We estimate that vaccination has accounted for 40% of the observed decline in global infant mortality, 52% in the African region. In 2024, a child younger than 10 years is 40% more likely to survive to their next birthday relative to a hypothetical scenario of no historical vaccination. Increased survival probability is observed even well into late adulthood. INTERPRETATION: Since 1974 substantial gains in childhood survival have occurred in every global region. We estimate that EPI has provided the single greatest contribution to improved infant survival over the past 50 years. In the context of strengthening primary health care, our results show that equitable universal access to immunisation remains crucial to sustain health gains and continue to save future lives from preventable infectious mortality. FUNDING: WHO.


Asunto(s)
Mortalidad del Niño , Programas de Inmunización , Vacunación , Humanos , Lactante , Preescolar , Vacunación/estadística & datos numéricos , Mortalidad del Niño/tendencias , Mortalidad Infantil/tendencias , Niño , Salud Global , Recién Nacido , Adulto , Adolescente , Historia del Siglo XX , Persona de Mediana Edad , Modelos Estadísticos , Salud Pública , Adulto Joven
2.
MMWR Morb Mortal Wkly Rep ; 72(46): 1262-1268, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37971951

RESUMEN

Measles is a highly contagious, vaccine-preventable disease that requires high population immunity for transmission to be interrupted. All six World Health Organization regions have committed to eliminating measles; however, no region has achieved and sustained measles elimination. This report describes measles elimination progress during 2000-2022. During 2000-2019, estimated coverage worldwide with the first dose of measles-containing vaccine (MCV) increased from 72% to 86%, then declined to 81% in 2021 during the COVID-19 pandemic, representing the lowest coverage since 2008. In 2022, first-dose MCV coverage increased to 83%. Only one half (72) of 144 countries reporting measles cases achieved the measles surveillance indicator target of two or more discarded cases per 100,000 population in 2022. During 2021-2022, estimated measles cases increased 18%, from 7,802,000 to 9,232,300, and the number of countries experiencing large or disruptive outbreaks increased from 22 to 37. Estimated measles deaths increased 43% during 2021-2022, from 95,000 to 136,200. Nonetheless, an estimated 57 million measles deaths were averted by vaccination during 2000-2022. In 2022, measles vaccination coverage and global surveillance showed some recovery from the COVID-19 pandemic setbacks; however, coverage declined in low-income countries, and globally, years of suboptimal immunization coverage left millions of children unprotected. Urgent reversal of coverage setbacks experienced during the COVID-19 pandemic can be accomplished by renewing efforts to vaccinate all children with 2 MCV doses and strengthening surveillance, thereby preventing outbreaks and accelerating progress toward measles elimination.


Asunto(s)
COVID-19 , Sarampión , Niño , Humanos , Lactante , Pandemias , Erradicación de la Enfermedad , Programas de Inmunización , Incidencia , Sarampión/epidemiología , Sarampión/prevención & control , Vacuna Antisarampión , Vacunación , Vigilancia de la Población , COVID-19/epidemiología , COVID-19/prevención & control
3.
MMWR Morb Mortal Wkly Rep ; 71(47): 1489-1495, 2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36417303

RESUMEN

All six World Health Organization (WHO) regions have committed to eliminating measles.* The Immunization Agenda 2021-2030 (IA2030)† aims to achieve the regional targets as a core indicator of impact and positions measles as the tracer of a health system's ability to deliver essential childhood vaccines. IA2030 highlights the importance of ensuring rigorous measles surveillance systems to document immunity gaps and achieve 95% coverage with 2 timely doses of measles-containing vaccine (MCV) among children. This report describes progress toward measles elimination during 2000-2021 and updates a previous report (1). During 2000-2021, estimated global coverage with a first MCV dose (MCV1) increased from 72% to a peak of 86% in 2019, but decreased during the COVID-19 pandemic to 83% in 2020 and to 81% in 2021, the lowest MCV1 coverage recorded since 2008. All countries conducted measles surveillance, but only 47 (35%) of 135 countries reporting discarded cases§ achieved the sensitivity indicator target of two or more discarded cases per 100,000 population in 2021, indicating surveillance system underperformance in certain countries. Annual reported measles incidence decreased 88% during 2000-2016, from 145 to 18 cases per 1 million population, then rebounded to 120 in 2019 during a global resurgence (2), before declining to 21 in 2020 and to 17 in 2021. Large and disruptive outbreaks were reported in 22 countries. During 2000-2021, the annual number of estimated measles deaths decreased 83%, from 761,000 to 128,000; an estimated 56 million measles deaths were averted by vaccination. To regain progress and achieve regional measles elimination targets during and after the COVID-19 pandemic, accelerating targeted efforts is necessary to reach all children with 2 MCV doses while implementing robust surveillance and identifying and closing immunity gaps to prevent cases and outbreaks.


Asunto(s)
COVID-19 , Sarampión , Niño , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , Pandemias , Erradicación de la Enfermedad , Programas de Inmunización , Sarampión/epidemiología , Sarampión/prevención & control , Vacuna Antisarampión
4.
Lancet Glob Health ; 10(10): e1412-e1422, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36113527

RESUMEN

BACKGROUND: Marked reductions in the incidence of measles and rubella have been observed since the widespread use of the measles and rubella vaccines. Although no global goal for measles eradication has been established, all six WHO regions have set measles elimination targets. However, a gap remains between current control levels and elimination targets, as shown by large measles outbreaks between 2017 and 2019. We aimed to model the potential for measles and rubella elimination globally to inform a WHO report to the 73rd World Health Assembly on the feasibility of measles and rubella eradication. METHODS: In this study, we modelled the probability of measles and rubella elimination between 2020 and 2100 under different vaccination scenarios in 93 countries of interest. We evaluated measles and rubella burden and elimination across two national transmission models each (Dynamic Measles Immunisation Calculation Engine [DynaMICE], Pennsylvania State University [PSU], Johns Hopkins University, and Public Health England models), and one subnational measles transmission model (Institute for Disease Modeling model). The vaccination scenarios included a so-called business as usual approach, which continues present vaccination coverage, and an intensified investment approach, which increases coverage into the future. The annual numbers of infections projected by each model, country, and vaccination scenario were used to explore if, when, and for how long the infections would be below a threshold for elimination. FINDINGS: The intensified investment scenario led to large reductions in measles and rubella incidence and burden. Rubella elimination is likely to be achievable in all countries and measles elimination is likely in some countries, but not all. The PSU and DynaMICE national measles models estimated that by 2050, the probability of elimination would exceed 75% in 14 (16%) and 36 (39%) of 93 modelled countries, respectively. The subnational model of measles transmission highlighted inequity in routine coverage as a likely driver of the continuance of endemic measles transmission in a subset of countries. INTERPRETATION: To reach regional elimination goals, it will be necessary to innovate vaccination strategies and technologies that increase spatial equity of routine vaccination, in addition to investing in existing surveillance and outbreak response programmes. FUNDING: WHO, Gavi, the Vaccine Alliance, US Centers for Disease Control and Prevention, and the Bill & Melinda Gates Foundation.


Asunto(s)
Sarampión , Rubéola (Sarampión Alemán) , Erradicación de la Enfermedad , Estudios de Factibilidad , Humanos , Sarampión/epidemiología , Sarampión/prevención & control , Rubéola (Sarampión Alemán)/epidemiología , Rubéola (Sarampión Alemán)/prevención & control , Estados Unidos , Vacunación
5.
Sci Rep ; 12(1): 3313, 2022 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-35228585

RESUMEN

Large US colleges and universities that re-opened campuses in the fall of 2020 and the spring of 2021 experienced high per capita rates of COVID-19. Returns to campus were controversial because they posed a potential risk to surrounding communities. A large university in Pennsylvania that returned to in-person instruction for Fall 2020 and Spring 2021 semesters reported high incidence of COVID-19 among students. However, the co-located non-student resident population in the county experienced fewer COVID-19 cases per capita than reported in neighboring counties. Activity patterns from mobile devices indicate that the non-student resident population near the university restricted their movements during the pandemic more than residents of neighboring counties. Respiratory virus prevention and management in student and non-student populations requires different, specifically targeted strategies.


Asunto(s)
Prueba de COVID-19 , COVID-19 , Tamizaje Masivo , Pandemias , COVID-19/diagnóstico , COVID-19/epidemiología , Humanos , Incidencia , Pennsylvania/epidemiología , SARS-CoV-2 , Universidades
6.
MMWR Morb Mortal Wkly Rep ; 70(45): 1563-1569, 2021 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-34758014

RESUMEN

In 2012, the World Health Assembly endorsed the Global Vaccine Action Plan,* with the objective of eliminating measles† in five of the six World Health Organization (WHO) regions by 2020 (1). The Immunization Agenda 2021-2030 (IA2030)§ uses measles incidence as an indicator of the strength of immunization systems. The Measles-Rubella Strategic Framework 2021-2030¶ and the Measles Outbreaks Strategic Response Plan 2021-2023** are aligned with the IA2030 and highlight robust measles surveillance systems to document immunity gaps, identify root causes of undervaccination, and develop locally tailored solutions to ensure administration of 2 doses of measles-containing vaccine (MCV) to all children. This report describes progress toward World Health Assembly milestones and measles elimination objectives during 2000-2020 and updates a previous report (2). During 2000-2010, estimated MCV first dose (MCV1) coverage increased globally from 72% to 84%, peaked at 86% in 2019, but declined to 84% in 2020 during the COVID-19 pandemic. All countries conducted measles surveillance, although fewer than one third achieved the sensitivity indicator target of ≥2 discarded†† cases per 100,000 population in 2020. Annual reported measles incidence decreased 88% during 2000-2016, from 145 to 18 cases per 1 million population, rebounded to 120 in 2019, before falling to 22 in 2020. During 2000-2020, the annual number of estimated measles deaths decreased 94%, from 1,072,800 to 60,700, averting an estimated 31.7 million measles deaths. To achieve regional measles elimination targets, enhanced efforts are needed to reach all children with 2 MCV doses, implement robust surveillance, and identify and close immunity gaps.


Asunto(s)
Erradicación de la Enfermedad , Salud Global/estadística & datos numéricos , Sarampión/prevención & control , Niño , Humanos , Programas de Inmunización , Incidencia , Lactante , Sarampión/epidemiología , Vacuna Antisarampión/administración & dosificación , Organización Mundial de la Salud
7.
RSC Adv ; 8(16): 8580-8585, 2018 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35539859

RESUMEN

Novel phtotpolymerisable hole-transport layers based on novel triazatruxenes incorporating six non-conjugated dienes as photo cross-linkable end-groups attached to flexible, aliphatic spacers have been synthesised using simple one-step substitution reactions. Hole-only test devices, fabricated using a combination of solution-deposition, spin-coating and initiator-free photochemical cross-linking of these photopolymerisable triazatruxenes, exhibit almost identical current density vs. voltage profiles before and after cross-linking, and as such, represent a promising new class of hole-transport layer for plastic electronic devices.

8.
Artículo en Inglés | MEDLINE | ID: mdl-24384573

RESUMEN

People around the world have folk origin myths, stories that explain where they came from and account for their place in the world and their differences from other peoples. As scientists, however, we claim to be seeking literal historical truth. In Western culture, typological ideas about human variation are at least as ancient as written discussion of the subject, and have dominated both social and scientific thinking about race. From Herodotus to the Biblical lost tribes of Israel, and surprisingly even to today, it has been common to view our species as composed of distinct, or even discrete groups, types, or "races," with other individuals admixed from among those groups. Such rhetoric goes so much against the well-known evolutionary realities that it must reflect something deep about human thought, at least in Western culture. Typological approaches can be convenient for some pragmatic aspects of scientific analysis, but they can be seductively deceiving. We know how to think differently and should do so, given the historical abuses that have occurred as a result of typological thinking that seem always to lurk in the human heart.


Asunto(s)
Personalidad , Ciencia , Pensamiento , Humanos
9.
Eur J Hum Genet ; 20(2): 217-23, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21934707

RESUMEN

A common approach to genetic mapping of loci for complex diseases is to perform a genome-wide association study (GWAS) by analyzing a vast number of SNP markers in cohorts of unrelated cases and controls. A direct motivation for the case-control design is that unrelated, affected individuals can be easier to collect than large families with multiple affected persons in the Western world. Despite its higher potential power, investigators have not actively pursued family ascertainment in part because of a dearth of methods for analyzing such correlated data on a large scale. We examine the statistical properties of several commonly used family-based association tests, as to their performance using real-life mixtures of families and singletons taken from our own migraine and schizophrenia studies, as well as population-based data for a complex trait simulated with the evolutionary phenogenetic simulator, ForSim. In virtually every situation, the full likelihood-based methods in the PSEUDOMARKER program outperformed those implemented in FBAT, GENEHUNTER TDT, PLINK (family-based options), HRR/HHRR, QTDT, TRANSMIT, UNPHASED, MENDEL, and LAMP. We further show that GWAS is much more powerful when family samples are used rather than unrelateds, on a genotype-by-genotype basis.


Asunto(s)
Ligamiento Genético , Predisposición Genética a la Enfermedad , Pruebas Genéticas/estadística & datos numéricos , Sesgo , Biometría , Salud de la Familia , Estudio de Asociación del Genoma Completo , Humanos , Desequilibrio de Ligamiento , Trastornos Migrañosos/epidemiología , Trastornos Migrañosos/genética , Linaje , Esquizofrenia/epidemiología , Esquizofrenia/genética , Programas Informáticos
10.
Am J Phys Anthropol ; 146 Suppl 53: 3-18, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22101685

RESUMEN

The Red Queen in "Through the Looking Glass" is often used as a metaphor for the relentless, unremitting competitive struggle by which Darwin described life. That imagery fits comfortably in our culture, with its emphasis on competition and inequity, but less so for nature herself. Life is manifestly much more about cooperation, at all levels and through a variety of ubiquitous mechanisms, than it is about competition. Most organisms of most species are nowhere near the proverbial Malthusian edge of survival, such that selection will detect the tiniest difference in their performance and enhance its genetic basis. Cooperation through interaction of multiple entities is inherent in many fundamental aspects of life, and its importance is not widely enough appreciated. Here we discuss a set of principles by which this works. We illustrate the points with a computer simulation of a topic of interest to anthropology, the development of the head. In a sense, our culture has its metaphors reversed. The red royal family is a more accurate symbol for the true nature of life, human or otherwise.


Asunto(s)
Evolución Biológica , Conducta Cooperativa , Biología Evolutiva , Animales , Simulación por Computador , Flujo Genético , Humanos , Modelos Biológicos , Selección Genética
11.
Hum Hered ; 71(4): 256-66, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21811076

RESUMEN

A decade ago, there was widespread enthusiasm for the prospects of genome-wide association studies to identify common variants related to common chronic diseases using samples of unrelated individuals from populations. Although technological advancements allow us to query more than a million SNPs across the genome at low cost, a disappointingly small fraction of the genetic portion of common disease etiology has been uncovered. This has led to the hypothesis that less frequent variants might be involved, stimulating a renaissance of the traditional approach of seeking genes using multiplex families from less diverse populations. However, by using the modern genotyping and sequencing technology, we can now look not just at linkage, but jointly at linkage and linkage disequilibrium (LD) in such samples. Software methods that can look simultaneously at linkage and LD in a powerful and robust manner have been lacking. Most algorithms cannot jointly analyze datasets involving families of varying structures in a statistically or computationally efficient manner. We have implemented previously proposed statistical algorithms in a user-friendly software package, PSEUDOMARKER. This paper is an announcement of this software package. We describe the motivation behind the approach, the statistical methods, and software, and we briefly demonstrate PSEUDOMARKER's advantages over other packages by example.


Asunto(s)
Mapeo Cromosómico/métodos , Ligamiento Genético , Estudio de Asociación del Genoma Completo/métodos , Desequilibrio de Ligamiento , Estudios de Casos y Controles , Frecuencia de los Genes , Sitios Genéticos , Humanos , Funciones de Verosimilitud , Proyectos de Investigación , Programas Informáticos
12.
Ann Hum Genet ; 75(3): 334-43, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21488850

RESUMEN

This journal began in 1925 as the Annals of Eugenics. Much has changed since then. The original Editors' primary eugenic objective was not achieved, and eugenics justifiably became notorious for racism and gross abuse of human rights. But one founding aim was to publish advances in statistical genetics, and that objective prospered in the journal's pages from its beginning to the present day. The online availability of the original issues will be useful to those interested in the history of both eugenics and human genetics and will provide a reminder of how the careless use of genetical concepts can go astray.


Asunto(s)
Eugenesia , Genética Médica , Publicaciones Periódicas como Asunto , Evolución Biológica , Emigración e Inmigración/legislación & jurisprudencia , Eugenesia/historia , Genética Médica/historia , Historia del Siglo XX , Humanos , Publicaciones Periódicas como Asunto/historia , Prejuicio , Grupos Raciales
13.
Bioinformatics ; 24(16): 1821-2, 2008 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-18565989

RESUMEN

UNLABELLED: Many important problems in biology involve complex traits affected by multiple coding or regulatory parts of the genome. How well the underlying genetic architecture can be inferred by statistical methods such as mapping and association studies are active research areas. ForSim is a flexible forward evolutionary simulation tool for exploring the consequences of evolution by phenotype, whereby demographic, chance, behavioral and selective effects mold genetic architecture. Simulation is useful for exploring these issues as well as the choice of study design inferential methods. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Artefactos , Mapeo Cromosómico/métodos , Evolución Molecular , Modelos Genéticos , Sitios de Carácter Cuantitativo/genética , Carácter Cuantitativo Heredable , Programas Informáticos
14.
Lancet ; 368(9554): 2226-30, 2006 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-17189034

RESUMEN

BACKGROUND: Transmissible spongiform encephalopathies (TSE) can be contracted through blood transfusion. Selective adsorption of the causative agent from donated blood might be one of the best ways of managing this risk. In our study, affinity resin L13, which reduces brain-derived infectivity spiked into human red blood cell concentrate by around 4 log(10)ID(50), and its equivalent, L13A, produced on a manufacturing scale, were assessed for their ability to remove TSE infectivity endogenously present in blood. METHODS: 500 mL of scrapie-infected hamster whole blood was leucoreduced at full scale before passage through the affinity resins. Infectivity of whole blood, leucoreduced whole blood (challenge), and the recovered blood from each flow-through was measured by limiting dilution titration. FINDINGS: Leucoreduction removed 72% of input infectivity. 15 of 99 animals were infected by the challenge, whereas none of the 96 or 100 animals inoculated with the final flow-throughs from either resin developed the disease after 540 days. The limit of detection of the bioassay was 0.2 infectious doses per mL. The overall reduction of the challenge infectivity was more than 1.22 log10ID. The results showed removal of endogenous TSE infectivity from leucoreduced whole blood by affinity ligands. The same resins adsorb normal and abnormal prion protein from human infections with variant, sporadic, and familial Creutzfeldt-Jakob disease, in the presence of blood components. INTERPRETATION: TSE affinity ligands, when incorporated into appropriate devices, can be used to mitigate the risks from TSE-infected blood, blood products, and other materials exposed to TSE infectivity.


Asunto(s)
Filtración/métodos , Enfermedades por Prión/prevención & control , Priones/aislamiento & purificación , Adsorción , Animales , Cricetinae , Enfermedades por Prión/transmisión , Priones/sangre , Priones/patogenicidad , Reacción a la Transfusión
15.
Transfusion ; 46(7): 1152-61, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16836562

RESUMEN

BACKGROUND: There is a demonstrated risk of infection by transmissible spongiform encephalopathies (TSEs) through transfusion from asymptomatic donors. Currently, blood-borne TSE infectivity cannot be detected with a diagnostic test, nor is it likely to be amenable to inactivation; however, its depletion with specific adsorp-tive ligand resins is possible. STUDY DESIGN AND METHODS: Six ligands that bind the prion protein, PrP, were selected by screening large solid-phase combinatorial chemical libraries. The selected resins were placed in columns and challenged with a unit of leukoreduced human red blood cells (RBCs) spiked with hamster brain-derived scrapie infectivity. The performance of each ligand was assessed by comparing the TSE infectivity titer in the RBCs before and after passage through each of five resin columns in series. RESULTS: Four resins were able to reduce infectivity titer by 3 to more than 4 log ID(50) per mL. The reduction was not due to nonspecific matrix interactions since a chemical modification of the most effective ligand completely abolished its ability to bind infectivity (negative control). A small subfraction of the infectivity, 0.01 percent, could not be removed, even upon repeated passage through successive columns. CONCLUSION: If endogenous TSE infectivity in RBCs binds to the ligands in the same proportion as brain-derived infectivity spiked into RBCs, the four most effective ligands would remove 3 to 4 log ID(50) per mL. A follow-up experiment is in progress to test whether endogenous blood-borne infectivity is also reduced.


Asunto(s)
Eritrocitos/química , Enfermedades por Prión/prevención & control , Priones/aislamiento & purificación , Animales , Técnicas Químicas Combinatorias , Cricetinae , Transfusión de Eritrocitos/métodos , Transfusión de Eritrocitos/normas , Humanos , Ligandos , Modelos Biológicos , Priones/sangre , Unión Proteica , Volumetría
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