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1.
medRxiv ; 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38826243

RESUMEN

Pathogen genomics can provide insights into disease transmission patterns, but new methods are needed to handle modern large-scale pathogen genome datasets. Genetically proximal viruses indicate epidemiological linkage and are informative about transmission events. Here, we leverage pairs of identical sequences using 114,298 SARS-CoV-2 genomes collected via sentinel surveillance from March 2021 to December 2022 in Washington State, USA, with linked age and residence information to characterize fine-scale transmission. The location of pairs of identical sequences is highly consistent with expectations from mobility and social contact data. Outliers in the relationship between genetic and mobility data can be explained by SARS-CoV-2 transmission between postal codes with male prisons, consistent with transmission between prison facilities. Transmission patterns between age groups vary across spatial scales. Finally, we use the timing of sequence collection to understand the age groups driving transmission. This work improves our ability to characterize transmission from large pathogen genome datasets.

2.
Cell ; 187(6): 1374-1386.e13, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38428425

RESUMEN

The World Health Organization declared mpox a public health emergency of international concern in July 2022. To investigate global mpox transmission and population-level changes associated with controlling spread, we built phylogeographic and phylodynamic models to analyze MPXV genomes from five global regions together with air traffic and epidemiological data. Our models reveal community transmission prior to detection, changes in case reporting throughout the epidemic, and a large degree of transmission heterogeneity. We find that viral introductions played a limited role in prolonging spread after initial dissemination, suggesting that travel bans would have had only a minor impact. We find that mpox transmission in North America began declining before more than 10% of high-risk individuals in the USA had vaccine-induced immunity. Our findings highlight the importance of broader routine specimen screening surveillance for emerging infectious diseases and of joint integration of genomic and epidemiological information for early outbreak control.


Asunto(s)
Enfermedades Transmisibles Emergentes , Epidemias , Mpox , Humanos , Brotes de Enfermedades , Mpox/epidemiología , Mpox/transmisión , Mpox/virología , Salud Pública , Monkeypox virus/fisiología
3.
PLoS Pathog ; 20(3): e1012117, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38530853

RESUMEN

SARS-CoV-2 transmission is largely driven by heterogeneous dynamics at a local scale, leaving local health departments to design interventions with limited information. We analyzed SARS-CoV-2 genomes sampled between February 2020 and March 2022 jointly with epidemiological and cell phone mobility data to investigate fine scale spatiotemporal SARS-CoV-2 transmission dynamics in King County, Washington, a diverse, metropolitan US county. We applied an approximate structured coalescent approach to model transmission within and between North King County and South King County alongside the rate of outside introductions into the county. Our phylodynamic analyses reveal that following stay-at-home orders, the epidemic trajectories of North and South King County began to diverge. We find that South King County consistently had more reported and estimated cases, COVID-19 hospitalizations, and longer persistence of local viral transmission when compared to North King County, where viral importations from outside drove a larger proportion of new cases. Using mobility and demographic data, we also find that South King County experienced a more modest and less sustained reduction in mobility following stay-at-home orders than North King County, while also bearing more socioeconomic inequities that might contribute to a disproportionate burden of SARS-CoV-2 transmission. Overall, our findings suggest a role for local-scale phylodynamics in understanding the heterogeneous transmission landscape.


Asunto(s)
COVID-19 , Epidemias , Humanos , SARS-CoV-2/genética , COVID-19/epidemiología , Washingtón/epidemiología
4.
medRxiv ; 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-37577709

RESUMEN

The World Health Organization declared mpox a public health emergency of international concern in July 2022. To investigate global mpox transmission and population-level changes associated with controlling spread, we built phylogeographic and phylodynamic models to analyze MPXV genomes from five global regions together with air traffic and epidemiological data. Our models reveal community transmission prior to detection, changes in case-reporting throughout the epidemic, and a large degree of transmission heterogeneity. We find that viral introductions played a limited role in prolonging spread after initial dissemination, suggesting that travel bans would have had only a minor impact. We find that mpox transmission in North America began declining before more than 10% of high-risk individuals in the USA had vaccine-induced immunity. Our findings highlight the importance of broader routine specimen screening surveillance for emerging infectious diseases and of joint integration of genomic and epidemiological information for early outbreak control.

5.
medRxiv ; 2022 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-36561171

RESUMEN

SARS-CoV-2 transmission is largely driven by heterogeneous dynamics at a local scale, leaving local health departments to design interventions with limited information. We analyzed SARS-CoV-2 genomes sampled between February 2020 and March 2022 jointly with epidemiological and cell phone mobility data to investigate fine scale spatiotemporal SARS-CoV-2 transmission dynamics in King County, Washington, a diverse, metropolitan US county. We applied an approximate structured coalescent approach to model transmission within and between North King County and South King County alongside the rate of outside introductions into the county. Our phylodynamic analyses reveal that following stay-at-home orders, the epidemic trajectories of North and South King County began to diverge. We find that South King County consistently had more reported and estimated cases, COVID-19 hospitalizations, and longer persistence of local viral transmission when compared to North King County, where viral importations from outside drove a larger proportion of new cases. Using mobility and demographic data, we also find that South King County experienced a more modest and less sustained reduction in mobility following stay-at-home orders than North King County, while also bearing more socioeconomic inequities that might contribute to a disproportionate burden of SARS-CoV-2 transmission. Overall, our findings suggest a role for local-scale phylodynamics in understanding the heterogeneous transmission landscape.

6.
Clin Infect Dis ; 75(1): e536-e544, 2022 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-35412591

RESUMEN

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic is dominated by variant viruses; the resulting impact on disease severity remains unclear. Using a retrospective cohort study, we assessed the hospitalization risk following infection with 7 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants. METHODS: Our study includes individuals with positive SARS-CoV-2 reverse transcription polymerase chain reaction (RT-PCR) in the Washington Disease Reporting System with available viral genome data, from 1 December 2020 to 14 January 2022. The analysis was restricted to cases with specimens collected through sentinel surveillance. Using a Cox proportional hazards model with mixed effects, we estimated hazard ratios (HR) for hospitalization risk following infection with a variant, adjusting for age, sex, calendar week, and vaccination. RESULTS: In total, 58 848 cases were sequenced through sentinel surveillance, of which 1705 (2.9%) were hospitalized due to COVID-19. Higher hospitalization risk was found for infections with Gamma (HR 3.20, 95% confidence interval [CI] 2.40-4.26), Beta (HR 2.85, 95% CI 1.56-5.23), Delta (HR 2.28 95% CI 1.56-3.34), or Alpha (HR 1.64, 95% CI 1.29-2.07) compared to infections with ancestral lineages; Omicron (HR 0.92, 95% CI .56-1.52) showed no significant difference in risk. Following Alpha, Gamma, or Delta infection, unvaccinated patients show higher hospitalization risk, while vaccinated patients show no significant difference in risk, both compared to unvaccinated, ancestral lineage cases. Hospitalization risk following Omicron infection is lower with vaccination. CONCLUSIONS: Infection with Alpha, Gamma, or Delta results in a higher hospitalization risk, with vaccination attenuating that risk. Our findings support hospital preparedness, vaccination, and genomic surveillance.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiología , Hospitalización , Humanos , Estudios Retrospectivos , SARS-CoV-2/genética , Washingtón/epidemiología
7.
medRxiv ; 2022 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-34729567

RESUMEN

BACKGROUND: The COVID-19 pandemic is dominated by variant viruses; the resulting impact on disease severity remains unclear. Using a retrospective cohort study, we assessed the hospitalization risk following infection with seven SARS-CoV-2 variants. METHODS: Our study includes individuals with positive SARS-CoV-2 RT-PCR in the Washington Disease Reporting System with available viral genome data, from December 1, 2020 to January 14, 2022. The analysis was restricted to cases with specimens collected through sentinel surveillance. Using a Cox proportional hazards model with mixed effects, we estimated hazard ratios (HR) for hospitalization risk following infection with a variant, adjusting for age, sex, calendar week, and vaccination. FINDINGS: 58,848 cases were sequenced through sentinel surveillance, of which 1705 (2.9%) were hospitalized due to COVID-19. Higher hospitalization risk was found for infections with Gamma (HR 3.20, 95%CI 2.40-4.26), Beta (HR 2.85, 95%CI 1.56-5.23), Delta (HR 2.28 95%CI 1.56-3.34) or Alpha (HR 1.64, 95%CI 1.29-2.07) compared to infections with ancestral lineages; Omicron (HR 0.92, 95%CI 0.56-1.52) showed no significant difference in risk. Following Alpha, Gamma, or Delta infection, unvaccinated patients show higher hospitalization risk, while vaccinated patients show no significant difference in risk, both compared to unvaccinated, ancestral lineage cases. Hospitalization risk following Omicron infection is lower with vaccination. CONCLUSION: Infection with Alpha, Gamma, or Delta results in a higher hospitalization risk, with vaccination attenuating that risk. Our findings support hospital preparedness, vaccination, and genomic surveillance. SUMMARY: Hospitalization risk following infection with SARS-CoV-2 variant remains unclear. We find a higher hospitalization risk in cases infected with Alpha, Beta, Gamma, and Delta, but not Omicron, with vaccination lowering risk. Our findings support hospital preparedness, vaccination, and genomic surveillance.

8.
Cell ; 175(4): 1088-1104.e23, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30318146

RESUMEN

Despite the known causality of copy-number variations (CNVs) to human neurodevelopmental disorders, the mechanisms behind each gene's contribution to the constellation of neural phenotypes remain elusive. Here, we investigated the 7q11.23 CNV, whose hemideletion causes Williams syndrome (WS), and uncovered that mitochondrial dysfunction participates in WS pathogenesis. Dysfunction is facilitated in part by the 7q11.23 protein DNAJC30, which interacts with mitochondrial ATP-synthase machinery. Removal of Dnajc30 in mice resulted in hypofunctional mitochondria, diminished morphological features of neocortical pyramidal neurons, and altered behaviors reminiscent of WS. The mitochondrial features are consistent with our observations of decreased integrity of oxidative phosphorylation supercomplexes and ATP-synthase dimers in WS. Thus, we identify DNAJC30 as an auxiliary component of ATP-synthase machinery and reveal mitochondrial maladies as underlying certain defects in brain development and function associated with WS.


Asunto(s)
Complejos de ATP Sintetasa/metabolismo , Encéfalo/metabolismo , Proteínas del Choque Térmico HSP40/metabolismo , Mitocondrias/metabolismo , Síndrome de Williams/genética , Animales , Encéfalo/crecimiento & desarrollo , Células Cultivadas , Femenino , Células HEK293 , Proteínas del Choque Térmico HSP40/genética , Humanos , Macaca mulatta , Masculino , Ratones , Ratones Endogámicos C57BL , Fosforilación Oxidativa
9.
J Biomater Sci Polym Ed ; 22(13): 1799-810, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-20843435

RESUMEN

In medicine, micro-electro-mechanical systems (MEMS) perform several specific functions. The design of bio-packages for MEMS to be implanted into the human body has been an increasing challenge in the last years. Mechanical, chemical and thermal resistance, as well as excellent bonding to silicon surfaces, are needed. Furthermore, ideal bio-packages should minimize post-operative complications and be well accepted by the host. To reach this goal, two different morphology-controlled hydroxyapatite-based porous biomaterials were synthesized, implanted in rats and evaluated mechanically and histologically. The novel biomaterials were prepared at room temperature using synthetic hydroxyapatite micro-particles, silica nanoparticles and water-based resin and compared with a standard hydroxyapatite biomaterial. The morphology (porosity) was controlled to obtain interconnected pores with appropriated pore size and pore volume fraction. All biomaterials were implanted in rats at the dorsal area near the third thoracic vertebra. The rats were killed 2, 7 and 21 days after surgery. Histological analysis revealed that the implants were well accepted by the host and minimal local inflammation was observed. The acute inflammatory response disappeared 21 days after surgery for both novel biomaterials. Additionally, organic matter (collagen) was produced in the interior of the porous biomaterial, indicating that an incipient vascularization process was in progress after 21 days of implantation. Both new biomaterials showed high abrasion resistance, high Young modulus, the appropriate porosity to allow possible vascularization, and good bonding to silicon surfaces.


Asunto(s)
Materiales Biocompatibles/química , Durapatita/química , Prótesis e Implantes , Animales , Colágeno/química , Colágeno/metabolismo , Sistemas Microelectromecánicos , Porosidad , Ratas
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