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1.
Mol Biol Evol ; 40(2)2023 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-36703230

RESUMEN

Migratory birds play a critical role in the rapid spread of highly pathogenic avian influenza (HPAI) H5N8 virus clade 2.3.4.4 across Eurasia. Elucidating the timing and pattern of virus transmission is essential therefore for understanding the spatial dissemination of these viruses. In this study, we surveyed >27,000 wild birds in China, tracked the year-round migration patterns of 20 bird species across China since 2006, and generated new HPAI H5N8 virus genomic data. Using this new data set, we investigated the seasonal transmission dynamics of HPAI H5N8 viruses across Eurasia. We found that introductions of HPAI H5N8 viruses to different Eurasian regions were associated with the seasonal migration of wild birds. Moreover, we report a backflow of HPAI H5N8 virus lineages from Europe to Asia, suggesting that Europe acts as both a source and a sink in the global HPAI virus transmission network.


Asunto(s)
Subtipo H5N8 del Virus de la Influenza A , Virus de la Influenza A , Gripe Aviar , Animales , Subtipo H5N8 del Virus de la Influenza A/genética , Aves , Virus de la Influenza A/genética , Animales Salvajes , Gripe Aviar/epidemiología , Europa (Continente)/epidemiología , Asia/epidemiología , Filogenia , Brotes de Enfermedades
2.
Int J Health Geogr ; 17(1): 35, 2018 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-30314528

RESUMEN

BACKGROUND: Usutu virus (USUV) is a mosquito-borne flavivirus, reported in many countries of Africa and Europe, with an increasing spatial distribution and host range. Recent outbreaks leading to regional declines of European common blackbird (Turdus merula) populations and a rising number of human cases emphasize the need for increased awareness and spatial risk assessment. METHODS: Modelling approaches in ecology and epidemiology differ substantially in their algorithms, potentially resulting in diverging model outputs. Therefore, we implemented a parallel approach incorporating two commonly applied modelling techniques: (1) Maxent, a correlation-based environmental niche model and (2) a mechanistic epidemiological susceptible-exposed-infected-removed (SEIR) model. Across Europe, surveillance data of USUV-positive birds from 2003 to 2016 was acquired to train the environmental niche model and to serve as test cases for the SEIR model. The SEIR model is mainly driven by daily mean temperature and calculates the basic reproduction number R0. The environmental niche model was run with long-term bio-climatic variables derived from the same source in order to estimate climatic suitability. RESULTS: Large areas across Europe are currently suitable for USUV transmission. Both models show patterns of high risk for USUV in parts of France, in the Pannonian Basin as well as northern Italy. The environmental niche model depicts the current situation better, but with USUV still being in an invasive stage there is a chance for under-estimation of risk. Areas where transmission occurred are mostly predicted correctly by the SEIR model, but it mostly fails to resolve the temporal dynamics of USUV events. High R0 values predicted by the SEIR model in areas without evidence for real-life transmission suggest that it may tend towards over-estimation of risk. CONCLUSIONS: The results from our parallel-model approach highlight that relying on a single model for assessing vector-borne disease risk may lead to incomplete conclusions. Utilizing different modelling approaches is thus crucial for risk-assessment of under-studied emerging pathogens like USUV.


Asunto(s)
Brotes de Enfermedades , Infecciones por Flavivirus/epidemiología , Flavivirus , Modelos Teóricos , Animales , Brotes de Enfermedades/prevención & control , Europa (Continente)/epidemiología , Infecciones por Flavivirus/diagnóstico , Infecciones por Flavivirus/transmisión , Humanos , Factores de Riesgo
3.
Viruses ; 13(6)2021 05 29.
Artículo en Inglés | MEDLINE | ID: mdl-34072346

RESUMEN

Chikungunya virus disease (chikungunya) is a mosquito-borne infectious disease reported in at least 50 countries, mostly in the tropics. It has spread around the globe within the last two decades, with local outbreaks in Europe. The vector mosquito Aedes albopictus (Diptera, Culicidae) has already widely established itself in southern Europe and is spreading towards central parts of the continent. Public health authorities and policymakers need to be informed about where and when a chikungunya transmission is likely to take place. Here, we adapted a previously published global ecological niche model (ENM) by including only non-tropical chikungunya occurrence records and selecting bioclimatic variables that can reflect the temperate and sub-tropical conditions in Europe with greater accuracy. Additionally, we applied an epidemiological model to capture the temporal outbreak risk of chikungunya in six selected European cities. Overall, the non-tropical ENM captures all the previous outbreaks in Europe, whereas the global ENM had underestimated the risk. Highly suitable areas are more widespread than previously assumed. They are found in coastal areas of the Mediterranean Sea, in the western part of the Iberian Peninsula, and in Atlantic coastal areas of France. Under a worst-case scenario, even large areas of western Germany and the Benelux states are considered potential areas of transmission. For the six selected European cities, June-September (the 22th-38th week) is the most vulnerable time period, with the maximum continuous duration of a possible transmission period lasting up to 93 days (Ravenna, Italy).


Asunto(s)
Aedes/virología , Fiebre Chikungunya/epidemiología , Fiebre Chikungunya/transmisión , Ecosistema , Mosquitos Vectores/virología , Animales , Virus Chikungunya/fisiología , Brotes de Enfermedades/prevención & control , Europa (Continente)/epidemiología , Humanos , Modelos Teóricos , Clima Tropical
4.
Epidemics ; 33: 100411, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33130413

RESUMEN

Epidemiological models (EMs) are widely used to predict the temporal outbreak risk of vector-borne diseases (VBDs). EMs typically use the basic reproduction number (R0), a threshold quantity, to indicate risk. To provide an overall view of the risk, these model outputs can be transformed into spatial risk maps, using various aggregation methods (e.g. average R0 over time, cumulative number of days with R0 > 1). However, there is no standardized methodology available for this. Depending on the specific aggregation methods used, the yielded spatial risk maps may have considerably different interpretations. Additionally, the method used to visualize the aggregated data also affects the perceived spatial patterns. In this review, we compare commonly used aggregation and visualization methods and discuss the respective interpretation of risk maps. Research publications using epidemiological modelling methods were drawn from Web of Science. Only publications containing maps of R0 transformed from EMs were considered for the analysis. An example EM was applied to illustrate how aggregation and visualization methods affect the final presentations of risk maps. Risk maps can be generated to show duration, intensity and spatio-temporal dynamics of potential outbreak risk of VBDs. We show that 1) different temporal aggregation methods lead to different interpretations; 2) similar spatial patterns do not necessarily bear the same meaning; 3) visualization methods considerably affect how results are perceived, and thus should be applied with caution. We recommend mapping both intensity and duration of the VBD outbreak risk, using small time-steps to show spatio-temporal dynamics when possible.


Asunto(s)
Monitoreo Epidemiológico , Enfermedades Transmitidas por Vectores/epidemiología , Animales , Número Básico de Reproducción , Brotes de Enfermedades , Humanos , Modelos Estadísticos
5.
Ann Clin Transl Neurol ; 7(7): 1141-1147, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32495505

RESUMEN

OBJECTIVE: Acute bilirubin encephalopathy (ABE) remains one of the important causes of neonatal mortality and child disability, early identification, and intervention which could improve outcomes. The purpose of this study was to evaluate early predictors of adverse outcomes in infants with ABE. METHODS: Newborns of gestational age ≥ 35 weeks and diagnosed with ABE were included in the study. Bilirubin-induced neurological dysfunction (BIND) score, total serum bilirubin (TSB) peak value, and serum albumin levels were determined. Adverse outcomes were defined as death or survival with auditory dysfunction and/or cerebral palsy. RESULTS: Eighty-two infants were eligible for recruitment in the study. The outcome data from 76 ABE infants (92%) were used for analysis, of which 25 infants got adverse outcomes and 51 live a normal life. Univariate analysis for BIND score, TSB peak value, bilirubin-albumin ratio (B/A), albumin level, abnormal AABR, and neonatal sepsis was performed to elucidate the association with adverse outcomes. Bivariate logistic regression analysis showed B/A (OR 10.48, 95%CI: 1.55-70.81, P = 0.02) and BIND score (OR 3.68, 95%CI: 1.39-9.72, P = 0.01) were correlated with adverse outcomes. ROC curve analysis showed that B/A (≥8.9 mg/g), BIND score (≥6) could predict adverse outcomes of ABE separately; B/A in conjunction with BIND score could increase prediction sensitivity to 100%. INTERPRETATION: Both B/A and BIND score can be used to predict adverse outcomes of ABE, and the combination of the two parameters can increase prediction sensitivity significantly.


Asunto(s)
Parálisis Cerebral/etiología , Pérdida Auditiva/etiología , Kernicterus/sangre , Kernicterus/complicaciones , Kernicterus/diagnóstico , Enfermedad Aguda , Bilirrubina/sangre , Estudios de Casos y Controles , Diagnóstico Precoz , Femenino , Humanos , Lactante , Recién Nacido , Kernicterus/mortalidad , Masculino , Muerte Perinatal , Pronóstico , Albúmina Sérica
6.
Ann Clin Transl Neurol ; 7(2): 210-218, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32031755

RESUMEN

OBJECTIVE: To determine the efficacy and the prognostic value of amplitude-integrated electroencephalography (aEEG) in term and near-term neonates with high risk of neurological sequelae. METHODS: Infants of ≥35 weeks of gestation diagnosed with neonatal encephalopathy or with high risk of brain injury were included. All eligible infants underwent aEEG within 6 h after clinical assessment. The infants were followed up 12 months to evaluate neurological development. RESULTS: A total of 250 infants were eligible, of which 85 had normal aEEG, 81 had mildly abnormal aEEG, and 84 had severely abnormal aEEG. Of these infants, 168 were diagnosed with different neonatal encephalopathies, 27 with congenital or metabolic diseases, and 55 with high risk of brain injury. In all, 22 infants died, 19 were lost to follow-up, and 209 completed the follow-up at 12 months, of which 62 were diagnosed with a neurological disability. Statistical analysis showed that severely abnormal aEEG predicted adverse neurological outcome with a sensitivity of 70.2%, a specificity of 87.1%, a positive predictive value of 75.6%, and a negative predictive value of 83.7%. INTERPRETATION: aEEG can predict adverse outcomes in high-risk neonates and is a useful method for monitoring neonates with high risk of adverse neurological outcomes.


Asunto(s)
Encefalopatías/diagnóstico , Electroencefalografía/normas , Enfermedades del Recién Nacido/diagnóstico , Lesiones Encefálicas/diagnóstico , Electroencefalografía/métodos , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Valor Predictivo de las Pruebas , Pronóstico , Riesgo
7.
Pediatr Neurol ; 98: 68-73, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31253564

RESUMEN

BACKGROUND: We aimed to determine the predictive neurological prognostic value of early amplitude-integrated electroencephalography (aEEG) in term and near-term neonates with severe hyperbilirubinemia compared with cranial magnetic resonance imaging (MRI) and auditory brainstem response (ABR). METHODS: Infants of ≥35 weeks of gestation with severe hyperbilirubinemia (total serum bilirubin [TSB] ≥340 µmol/L) or with hyperbilirubinemia (TSB ≥257 µmol/L) in association with bilirubin-induced neurological dysfunction were recruited. All the subjects had an aEEG after being admitted to the neonatal intensive care unit, whereas cranial MRI and ABR were performed when TSB had come down to the normal range. All the infants were followed up to 12 months. RESULTS: During the study period, 77 of 83 infants were eligible, of which 71 had severe hyperbilirubinemia and six had hyperbilirubinemia in association with bilirubin-induced neurological dysfunction. Thirty-three infants were diagnosed with acute bilirubin encephalopathy (ABE), two of whom died of ABE, and 62 completed the follow-up, of which 12 infants had adverse outcomes. Sixty-four infants underwent aEEG, 40 infants had cranial MRI, and 39 infants had ABR. Logistic regression and the receiver-operator characteristic curve analysis showed that the ability of severely abnormal aEEG to predict adverse neurological outcomes in severe hyperbilirubinemia was no better than abnormal ABR, with a sensitivity of 35.7% versus 83.3%, a specificity of 92.0% versus 74.1%, a positive predictive value of 55.6% versus 58.8%, and a negative predictive value of 83.6% versus 90.9%. CONCLUSIONS: Early aEEG could predict adverse neurodevelopmental outcomes in neonates with severe hyperbilirubinemia, although the sensitivity was lower than ABR.


Asunto(s)
Electroencefalografía , Potenciales Evocados Auditivos del Tronco Encefálico/fisiología , Hiperbilirrubinemia/diagnóstico , Kernicterus/diagnóstico , Femenino , Humanos , Hiperbilirrubinemia/complicaciones , Hiperbilirrubinemia/diagnóstico por imagen , Hiperbilirrubinemia/fisiopatología , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Kernicterus/diagnóstico por imagen , Kernicterus/etiología , Kernicterus/fisiopatología , Imagen por Resonancia Magnética , Masculino
8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 21(2): 415-8, 2013 Apr.
Artículo en Zh | MEDLINE | ID: mdl-23628044

RESUMEN

This study was purposed to explore the correlation of chromosome karyotype with dyshaematopoiesis and reticulin in myelodysplastic syndrome (MDS). The data of 202 MDS patients diagnosed and treated in the First Affiliated Hospital of Zhengzhou University were retrospectively analyzed in term of chromosome karyotype, dyshaematopoiesis and reticulin detection results. The chromosome karyotypes were categorized according to the International Prognostic Scoring System (IPSS). The results showed that there was a positive correlation between chromosome karyotype grading and number of lineages with dyshaematopoiesis (r = 0.443, P < 0.05). The detected rates of multilineage dyshaematopoiesis in patients with good, intermediate and poor chromosome karyotypes were 44.4%, 71.4% and 96.3% respectively. There was a positive correlation between chromosome karyotype grading and reticulin grading (r = 0.451, P < 0.05). The positive rates of reticulin in patients with good grading, intermediate and poor chromosome karyotypes were 36.8%, 64.3% and 92.6% respectively. The detected rate of multilineage dyshaematopoiesis, number of lineages with dyshaematopoiesis, the positive rate of reticulin and reticulin grade in patients with poor karyotypes were higher than those in patients with intermediate or good chromosome karyotypes (separately P < 0.01). The above data in patients with intermediate chromosome karyotypes were higher than those in patients with good chromosome karyotypes (separately P < 0.01). It is concluded that the chromosome karyotype grading positively correlates with the number of lineages with dyshaematopoiesis and reticulin grading. When the chromosome karyotype changed from good to poor, the detected rate of multilineage dyshaematopoiesis, number of lineages with dyshaematopoiesis, positive rate of reticulin and reticulin grading became higher and higher.


Asunto(s)
Cariotipo , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/patología , Reticulina/análisis , Adolescente , Adulto , Anciano , Examen de la Médula Ósea , Femenino , Humanos , Cariotipificación , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/diagnóstico , Estudios Retrospectivos , Adulto Joven
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