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1.
J. Health Biol. Sci. (Online) ; 10(1): 1-7, 01/jan./2022.
Artículo en Portugués | LILACS | ID: biblio-1361634

RESUMEN

Objetivo: aplicar a modelagem logística da primeira onda da COVID-19, com índice nos países com 20 maiores Produto Interno Bruto (PIB). Métodos: foi utilizada a modelagem matemática de crescimento logístico, considerando os seguintes parâmetros: número cumulativo de casos (C), tamanho final da epidemia na onda única de um surto (K), taxa intrínseca de crescimento (y) e tempo de inflexão (τ). Resultados: o Brasil apresentou maior número de casos e mortalidade, e os Estados Unidos da América (EUA) maior número de casos absolutos. A Coreia do Sul evidenciou o menor ponto de inflexão de 15,3 dias, enquanto o maior foi da Indonésia, com 213,9 dias. Na análise entre o ponto de inflexão e casos acumulados (/100 mil habitantes), observou-se correlação positiva moderada significativa (r=0,629 e p=0,003); (r=0,532 e p=0,016). Conclusão: o reconhecimento do comportamento de uma epidemia por meio da modelagem matemática torna possível determinar a propagação de uma epidemia, visto que, com a possibilidade de captar a dinâmica de uma epidemia, torna-se possível prever a necessidade de medidas públicas antecipadas e, consequentemente, diminuição da mortalidade global.


Objective: to apply logistic modeling of the first wave of COVID-19 in countries with the 20 highest Gross Domestic Product (GDP). Methods: logistic growth mathematical modeling was used, considering the following parameters: cumulative number of cases (C), the final size of the epidemic in the single wave of an outbreak (K), intrinsic growth rate (y), and inflection time (τ). Results: Brazil showed the highest number of cases and mortality, and the United States of America (USA) had the highest number of absolute cases. South Korea showed the lowest inflection point of 15.3 days, while the highest infection point was Indonesia, with 213.9 days. In the analysis between the inflection point and cumulative cases (/100,000 population), a moderate significant positive correlation was observed (r=0.629 and p=0.003); (r=0.532 and p=0.016). Conclusion: the recognition of the behavior of an epidemic through mathematical modeling makes it possible to determine the spread of an epidemic, since, with the possibility of capturing the dynamics of an epidemic, it becomes possible to predict the need for anticipated public measures and, consequently, decrease in overall mortality.


Asunto(s)
COVID-19 , Modelos Logísticos , Producto Interno Bruto , Epidemias
2.
J Infect Public Health ; 15(5): 594-598, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35500544

RESUMEN

BACKGROUND: Appropriate mitigation strategy to minimize enterovirus (EV) transmission among children is essential to control severe EV epidemics. Scientific evidence for the effectiveness of case isolation and class suspension is lacking. METHODS: EV-infected children ≤ eight years are asked to stay at home for seven days. Classes were suspended for seven days if there are more than two classmates having an onset of herpangina or hand, foot, and mouth disease in one classroom within one week. Study subjects are divided into two groups, group A with class suspension for one week and group B without class suspension. RESULTS: Among 4153 reported EV-infected children from 1085 classes in May and June, 2015 were enrolled. Median incidence of EV infection in a class was 7% (range 3% -60%). The incidence was higher in group A (median 14%, range 3-60%) than that in group B (median 6%, range 3-80%) (P < 0.01). The median incidence is highest in day care center (20%), followed by kindergarten (8%), and primary school (4%) (P < 0.01). Most secondary cases in group A appeared within seven days after the disease onset of index case in the same class. The incidence of EV infection remained low and was similar between the two groups eight days and beyond after the disease onset of index cases. CONCLUSIONS: Targeted class suspension for seven days with case isolation for seven days is an effective measure to mitigate transmission of EV infection in children.


Asunto(s)
Infecciones por Enterovirus , Enterovirus , Epidemias , Enfermedad de Boca, Mano y Pie , Herpangina , Niño , Infecciones por Enterovirus/epidemiología , Infecciones por Enterovirus/prevención & control , Enfermedad de Boca, Mano y Pie/epidemiología , Herpangina/epidemiología , Humanos , Lactante
3.
Cad Saude Publica ; 38(4): e00104221, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35508028

RESUMEN

This article uses a socio-anthropological framework to explore the stigmas around interactions with children born with congenital Zika syndrome caused by the Zika virus epidemic in two Brazilian municipalities. Semi-structured interviews were conducted with parents and other relatives. We reflected on the search for meaning when having a baby with unexpected body marks, the moral suffering, the societal ableism, the burden of care, and the need for support networks. We concluded that public policies, especially social policies (health, education, and social assistance), are essential for compensatory mechanisms, recognition, and social inclusion of these children and their families.


Asunto(s)
Epidemias , Microcefalia , Infección por el Virus Zika , Virus Zika , Brasil/epidemiología , Niño , Humanos , Lactante , Microcefalia/epidemiología , Microcefalia/etiología , Estigma Social , Infección por el Virus Zika/epidemiología
4.
Rev Soc Bras Med Trop ; 55: e02742021, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35522806

RESUMEN

BACKGROUND: French Guiana (FG) is an ultra-peripheral European region in the Amazon, and the COVID-19 epidemic has had very different kinetics from both its giant neighbors, Brazil or mainland France. METHODS: This study summarized the epidemics of COVID-19 in FG. RESULTS: The tropical climate, multiethnicity, and remoteness of the population forced healthcare providers to accordingly adapt the management of the epidemic. Incidence and mortality have been lower than that in Europe and Latin America due to a combination of prevalence of the youth in the population and highly developed healthcare system. CONCLUSIONS: Currently, vaccine hesitancy hinders the rapid expansion of vaccine coverage.


Asunto(s)
COVID-19 , Epidemias , Adolescente , Brasil , COVID-19/epidemiología , Europa (Continente) , Guyana Francesa/epidemiología , Humanos
5.
Rev Soc Bras Med Trop ; 55: e05592021, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35522810

RESUMEN

BACKGROUND: Malaria has unstable transmission in Colombia and has variable endemic-epidemic patterns. This study describes the epidemiological characteristics of malaria epidemics registered in Colombia from 1970-2019. METHODS: Data from 1979-2019 were collected from the National Public Health Surveillance System. The data was tabulated and pertinent descriptive analyses were carried out. RESULTS: Fifteen malaria outbreaks and approximately five-year-long epidemic cycles were observed in Colombia during the study period. CONCLUSIONS: Malaria epidemics in Colombia present a five-yearly transmission pattern, mainly due to the increased vulnerability produced by seasonal population migrations in receptive areas with active transmission.


Asunto(s)
Epidemias , Malaria , Colombia/epidemiología , Brotes de Enfermedades , Humanos , Malaria/epidemiología , Vigilancia en Salud Pública
8.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(4): 433-436, 2022 Apr 06.
Artículo en Chino | MEDLINE | ID: mdl-35535445

RESUMEN

Objective: To identify a suspected clustered Typhoid fever by whole genome sequencing(WGS) and pulsed field gel electrophoresis (PFGE) subtyping. Methods: The nature of the epidemic was determined by combination of subtyping results of isolates and epidemiological information. Results: Five S. typhimurium isolates showed identical PFGE patterns and almost the same whole genome sequence. Epidemiological survey showed that five cases had dined in the same restaurant on the same day. Conclusion: Combined with the longest incubation period of typhoid fever, molecular subtyping of pathogenic bacteria and the field epidemiological survey, it can be preliminarily determined that the five cases have common infection sources.


Asunto(s)
Epidemias , Fiebre Tifoidea , Electroforesis en Gel de Campo Pulsado , Humanos , Fiebre Tifoidea/epidemiología , Fiebre Tifoidea/microbiología
9.
J R Soc Interface ; 19(190): 20220048, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35537473

RESUMEN

Effective contact tracing is crucial to containing epidemic spreading without disrupting societal activities, especially during a pandemic. Large gatherings play a key role, potentially favouring superspreading events. However, the effects of tracing in large groups have not been fully assessed so far. We show that in addition to forward tracing, which reconstructs to whom the disease spreads, and backward tracing, which searches from whom the disease spreads, a third 'sideward' tracing is always present, when tracing gatherings. This is an indirect tracing that detects infected asymptomatic individuals, even if they have been neither directly infected by nor directly transmitted the infection to the index case. We analyse this effect in a model of epidemic spreading for SARS-CoV-2, within the framework of simplicial activity-driven temporal networks. We determine the contribution of the three tracing mechanisms to the suppression of epidemic spreading, showing that sideward tracing induces a non-monotonic behaviour in the tracing efficiency, as a function of the size of the gatherings. Based on our results, we suggest an optimal choice for the sizes of the gatherings to be traced and we test the strategy on an empirical dataset of gatherings on a university campus.


Asunto(s)
COVID-19 , Epidemias , COVID-19/epidemiología , COVID-19/prevención & control , Trazado de Contacto/métodos , Epidemias/prevención & control , Humanos , Pandemias/prevención & control , SARS-CoV-2 , Universidades
10.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 34(2): 191-193, 2022 Apr 12.
Artículo en Chino | MEDLINE | ID: mdl-35537843

RESUMEN

OBJECTIVE: To analyze and compare the epidemiological characteristics of imported malaria in Jiaozuo City before and after malaria elimination, so as to provide insights into the malaria surveillance during the post-elimination stage and prevention of re-establishment of imported malaria. METHODS: Data pertaining to the epidemic situation and individual investigation of malaria in Jiaozuo City before (from 2010 to 2016) and after malaria elimination (from 2017 to November, 2020) were captured from the National Notifiable Disease Reporting System and the Information System for Parasitic Diseases Control and Prevention of Chinese Center for Disease Control and Prevention and were analyzed statistically. RESULTS: A total of 74 imported malaria cases were reported in Jiaozuo City from 2010 to 2021. Imported cases were predominantly Plasmodium falciparum malaria cases in Jiaozuo City before and after malaria elimination, and there was no significant difference in the proportion of malaria parasite species (χ2 = 0.234, P > 0.05). The imported malaria cases was predominantly reported in Wuzhi County, and was identified in overseas male farmers and businessmen at ages of 20 to 59 years, while the greatest number of imported malaria cases was reported in June and December before and after malaria elimination. The imported malaria cases predominantly acquired malaria parasite infections in sub-Saharan African countries; however, the proportion of imported malaria cases returning from Southeast Asian counties increased after malaria elimination than before malaria elimination (χ2 = 5.989, P < 0.05). The longest duration from onset to definitive diagnosis of malaria reduced from 27 days before malaria elimination to 18 days after malaria elimination, and the median duration reduced from 3 days to 2 days, while the proportion of definitive diagnosis of malaria increased from 60.47% before malaria elimination to 83.87% after malaria elimination (χ2 = 4.724, P < 0.05). In addition, the proportion of malaria cases definitively diagnosed and reported by medical institutions increased after malaria elimination than before malaria elimination (χ2 = 5.406, P < 0.05). CONCLUSIONS: The imported malaria patients were predominantly P. falciparum malaria cases in Jiaozuo City during 2010 to 2021, and the patient's medical care-seeking awareness and medical staff's diagnosis and treatment ability have improved after malaria elimination. It is necessary to strengthen and improve malaria surveillance and response system and prevent the re-establishment of overseas imported malaria.


Asunto(s)
Enfermedades Transmisibles Importadas , Epidemias , Malaria Falciparum , Malaria , Adulto , China/epidemiología , Ciudades , Enfermedades Transmisibles Importadas/diagnóstico , Enfermedades Transmisibles Importadas/epidemiología , Enfermedades Transmisibles Importadas/prevención & control , Epidemias/prevención & control , Humanos , Malaria/epidemiología , Malaria/parasitología , Malaria/prevención & control , Malaria Falciparum/epidemiología , Masculino , Persona de Mediana Edad , Adulto Joven
11.
J Math Biol ; 84(6): 50, 2022 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-35513730

RESUMEN

We derive a stochastic SIS pairwise model by considering the change of the variables of this system caused by an event. Based on approximations, we construct a low-dimensional deterministic system that can be used to describe the epidemic spread on a regular network. The mathematical treatment of the model yields explicit expressions for the variances of each variable at equilibrium. Then a comparison between the stochastic pairwise model and the stochastic mean-field SIS model is performed to indicate the effect of network structure. We find that the variances of the prevalence of infection for these two models are almost equal when the number of neighbors of every individual is large. Furthermore, approximations for the quasi-stationary distribution of the number of infected individuals and the expected time to extinction starting in quasi-stationary are derived. We analyze the approximations for the critical number of neighbors and the persistence threshold based on the stochastic model. The approximate performance is then examined by numerical and stochastic simulations. Moreover, during the early development phase, the temporal variance of the infection is also obtained. The simulations show that our analytical results are asymptotically accurate and reasonable.


Asunto(s)
Epidemias , Modelos Biológicos , Simulación por Computador , Humanos , Procesos Estocásticos
12.
Proc Biol Sci ; 289(1974): 20220232, 2022 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-35506229

RESUMEN

There is known heterogeneity between individuals in infectious disease transmission patterns. The source of this heterogeneity is thought to affect epidemiological dynamics but studies tend not to control for the overall heterogeneity in the number of secondary cases caused by an infection. To explore the role of individual variation in infection duration and transmission rate in parasite emergence and spread, while controlling for this potential bias, we simulate stochastic outbreaks with and without parasite evolution. As expected, heterogeneity in the number of secondary cases decreases the probability of outbreak emergence. Furthermore, for epidemics that do emerge, assuming more realistic infection duration distributions leads to faster outbreaks and higher epidemic peaks. When parasites require adaptive mutations to cause large epidemics, the impact of heterogeneity depends on the underlying evolutionary model. If emergence relies on within-host evolution, decreasing the infection duration variance decreases the probability of emergence. These results underline the importance of accounting for realistic distributions of transmission rates to anticipate the effect of individual heterogeneity on epidemiological dynamics.


Asunto(s)
Brotes de Enfermedades , Epidemias , Humanos , Probabilidad
13.
Bull Math Biol ; 84(7): 68, 2022 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-35598221

RESUMEN

Host diversification methods such as within-field mixtures (or field mosaics, depending on the spatial scale considered) are promising methods for agroecological plant disease control. We explore disease spread in host mixtures (or field mosaics) composed of two host genotypes (susceptible and resistant). The pathogen population is composed of two genotypes (wild-type and resistance-breaking). We show that for intermediate fractions of resistant hosts, the spatial spread of the disease may be split into two successive fronts. The first front is led by the wild-type pathogen and the disease spreads faster, but at a lower prevalence, than in a resistant pure stand (or landscape). The second front is led by the resistance-breaking type, which spreads slower than in a pure resistant stand (or landscape). The wild-type and the resistance-breaking genotypes coexist behind the invasion fronts, resulting in the same prevalence as in a resistant pure stand. This study shows that host diversification methods may have a twofold effect on pathogen spread compared to a resistant pure stand (or landscape): on the one hand, they accelerate disease spread, and on the other hand they slow down the spread of the resistance-breaking genotype. This work contributes to a better understanding of the multiple effects underlying the performance of host diversification methods in agroecology.


Asunto(s)
Epidemias , Modelos Biológicos , Genotipo , Conceptos Matemáticos , Enfermedades de las Plantas/genética
15.
Glob Health Action ; 15(1): 2061240, 2022 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-35506948

RESUMEN

BACKGROUND: The Ebola virus is known as one of the deadliest pathogens to infect humans. Children represent a minority of Ebola Virus Disease cases globally. Yet, the different Ebola outbreaks in Africa had a wide impact on children's lives and children' rights. OBJECTIVE: Review the published literature to date on Children's rights during Ebola outbreaks. Outcomes shall contribute to get a better understanding of the main limitations or violations of children's rights, identify potential gaps in the literature and support the promotion and protection of children's rights for current and future health crisis. METHODS: A scoping review from PubMed, Medline, Cochrane Library and Web of Science was performed using PRISMA-ScR guidelines. Articles, reports and editorial, published on Ebola Outbreaks between 1976 and 2020 were retrieved. The UNCRC clusters of rights and treaty specific guidelines were used as a framework. Documents were found through a targeted search of websites from international or regional organisations involved in Ebola crises and children's protection. RESULTS: 48 articles and reports were reviewed. Few documents focused solely on children's rights. Several articles covered the topic of children and Ebola outbreaks. Most of the data are linked to basic health, education, discrimination of orphans and survivors. 31% of the reviewed articles underline the violence against the children (rape, abuse, Female genital mutilations), while 21% focus on the right to education. 23% cover the topic of orphans. Impact on mental health and SRH were amongst the other covered topics. CONCLUSION: A lack of data on children's rights and their violations during epidemics is observed. Regional and international collaboration is needed to document the situation of children in health emergencies. Health measures and strategies based on children's opinions and raising awareness of their crucial role in society is key. Child-centred guidelines should be developed based on these elements.


Asunto(s)
Maltrato a los Niños , Epidemias , Fiebre Hemorrágica Ebola , Niño , Maltrato a los Niños/prevención & control , Femenino , Fiebre Hemorrágica Ebola/epidemiología , Humanos , Salud Mental , Violencia
16.
Microb Genom ; 8(5)2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35532121

RESUMEN

Enterovirus D68 (EV-D68) has recently been identified in biennial epidemics coinciding with diagnoses of non-polio acute flaccid paralysis/myelitis (AFP/AFM). We investigated the prevalence, genetic relatedness and associated clinical features of EV-D68 in 193 EV-positive samples from 193 patients in late 2018, UK. EV-D68 was detected in 83 (58 %) of 143 confirmed EV-positive samples. Sequencing and phylogenetic analysis revealed extensive genetic diversity, split between subclades B3 (n=50) and D1 (n=33), suggesting epidemiologically unrelated infections. B3 predominated in children and younger adults, and D1 in older adults and the elderly (P=0.0009). Clinical presentation indicated causation or exacerbation of respiratory distress in 91.4 % of EV-D68-positive individuals, principally cough (75.3 %), shortness of breath (56.8 %), coryza (48.1 %), wheeze (46.9 %), supplemental oxygen required (46.9 %) and fever (38.9 %). Two cases of AFM were observed, one with EV-D68 detectable in the cerebrospinal fluid, but otherwise neurological symptoms were rarely reported (n=4). Both AFM cases and all additional instances of intensive care unit (ICU) admission (n=5) were seen in patients infected with EV-D68 subclade B3. However, due to the infrequency of severe infection in our cohort, statistical significance could not be assessed.


Asunto(s)
Enterovirus Humano D , Infecciones por Enterovirus , Epidemias , Anciano , Enfermedades Virales del Sistema Nervioso Central , Niño , Enterovirus Humano D/genética , Infecciones por Enterovirus/diagnóstico , Infecciones por Enterovirus/epidemiología , Variación Genética , Humanos , Mielitis , Enfermedades Neuromusculares , Filogenia , Reino Unido/epidemiología
17.
Sci Rep ; 12(1): 7637, 2022 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-35538100

RESUMEN

Notwithstanding a significant understanding of epidemic processes in biological, social, financial, and geophysical systems, little is known about contagion behavior in individual productivity and success. We introduce an epidemic model to study the contagion of scholarly productivity and YouTube success. Our analysis reveals the existence of synchronized bursts in individual productivity and success, which are likely mediated by sustained flows of information within the networks.


Asunto(s)
Eficiencia , Epidemias
18.
Philos Trans A Math Phys Eng Sci ; 380(2227): 20200412, 2022 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-35599564

RESUMEN

The behaviour of individuals is a main actor in the control of the spread of a communicable disease and, in turn, the spread of an infectious disease can trigger behavioural changes in a population. Here, we study the emergence of individuals' protective behaviours in response to the spread of a disease by considering two different social attitudes within the same population: concerned and risky. Generally speaking, concerned individuals have a larger risk aversion than risky individuals. To study the emergence of protective behaviours, we couple, to the epidemic evolution of a susceptible-infected-susceptible model, a decision game based on the perceived risk of infection. Using this framework, we find the effect of the protection strategy on the epidemic threshold for each of the two subpopulations (concerned and risky), and study under which conditions risky individuals are persuaded to protect themselves or, on the contrary, can take advantage of a herd immunity by remaining healthy without protecting themselves, thanks to the shield provided by concerned individuals. This article is part of the theme issue 'Emergent phenomena in complex physical and socio-technical systems: from cells to societies'.


Asunto(s)
Epidemias , Epidemias/prevención & control , Humanos
19.
Comput Math Methods Med ; 2022: 4150043, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35602345

RESUMEN

The role of human behaviour in the dynamics of infectious diseases cannot be underestimated. A clear understanding of how human behaviour influences the spread of infectious diseases is critical in establishing and designing control measures. To study the role that human behaviour plays in Ebola disease dynamics, in this paper, we design an Ebola virus disease model with disease transmission dynamics based on a new exponential nonlinear incidence function. This new incidence function that captures the reduction in disease transmission due to human behaviour innovatively considers the efficacy and the speed of behaviour change. The model's steady states are determined and suitable Lyapunov functions are built. The proofs of the global stability of equilibrium points are presented. To demonstrate the utility of the model, we fit the model to Ebola virus disease data from Liberia and Sierra Leone. The results which are comparable to existing findings from the outbreak of 2014 - 2016 show a better fit when the efficacy and the speed of behaviour change are higher. A rapid and efficacious behaviour change as a control measure to rapidly control an Ebola virus disease epidemic is advocated. Consequently, this model has implications for the management and control of future Ebola virus disease outbreaks.


Asunto(s)
Epidemias , Fiebre Hemorrágica Ebola , Brotes de Enfermedades/prevención & control , Fiebre Hemorrágica Ebola/prevención & control , Humanos , Incidencia , Sierra Leona/epidemiología
20.
Math Biosci Eng ; 19(6): 6088-6101, 2022 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-35603392

RESUMEN

Following the emergence and worldwide spread of coronavirus disease 2019 (COVID-19), each country has attempted to control the disease in different ways. The first patient with COVID-19 in Japan was diagnosed on 15 January 2020, and until 31 October 2020, the epidemic was characterized by two large waves. To prevent the first wave, the Japanese government imposed several control measures such as advising the public to avoid the 3Cs (closed spaces with poor ventilation, crowded places with many people nearby, and close-contact settings such as close-range conversations) and implementation of "cluster buster" strategies. After a major epidemic occurred in April 2020 (the first wave), Japan asked its citizens to limit their numbers of physical contacts and announced a non-legally binding state of emergency. Following a drop in the number of diagnosed cases, the state of emergency was gradually relaxed and then lifted in all prefectures of Japan by 25 May 2020. However, the development of another major epidemic (the second wave) could not be prevented because of continued chains of transmission, especially in urban locations. The present study aimed to descriptively examine propagation of the COVID-19 epidemic in Japan with respect to time, age, space, and interventions implemented during the first and second waves. Using publicly available data, we calculated the effective reproduction number and its associations with the timing of measures imposed to suppress transmission. Finally, we crudely calculated the proportions of severe and fatal COVID-19 cases during the first and second waves. Our analysis identified key characteristics of COVID-19, including density dependence and also the age dependence in the risk of severe outcomes. We also identified that the effective reproduction number during the state of emergency was maintained below the value of 1 during the first wave.


Asunto(s)
COVID-19 , Epidemias , Número Básico de Reproducción , COVID-19/epidemiología , Humanos , Japón/epidemiología , SARS-CoV-2
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