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1.
PLoS One ; 16(1): e0244983, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33400714

RESUMO

Here we look into the spread of aerosols indoors that may potentially carry viruses. Many viruses, including the novel SARS-CoV-2, are known to spread via airborne and air-dust pathways. From the literature data and our research on the propagation of fine aerosols, we simulate herein the carryover of viral aerosols in indoor air. We demonstrate that a lot of fine droplets released from an infected person's coughing, sneezing, or talking propagate very fast and for large distances indoors, as well as bend around obstacles, lift up and down over staircases, and so on. This study suggests equations to evaluate the concentration of those droplets, depending on time and distance from the source of infection. Estimates are given for the safe distance to the source of infection, and available methods for neutralizing viral aerosols indoors are considered.


Assuntos
/transmissão , Transmissão de Doença Infecciosa/prevenção & controle , Aerossóis/análise , Microbiologia do Ar , Poluição do Ar em Ambientes Fechados/análise , /virologia , Tosse , Transmissão de Doença Infecciosa/estatística & dados numéricos , Poeira , Humanos , Modelos Teóricos , Espirro/fisiologia , Viroses/prevenção & controle
2.
PLoS One ; 16(1): e0241190, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33406134

RESUMO

Multiple national and international trends and drivers are radically changing what biological security means for the United Kingdom (UK). New technologies present novel opportunities and challenges, and globalisation has created new pathways and increased the speed, volume and routes by which organisms can spread. The UK Biological Security Strategy (2018) acknowledges the importance of research on biological security in the UK. Given the breadth of potential research, a targeted agenda identifying the questions most critical to effective and coordinated progress in different disciplines of biological security is required. We used expert elicitation to generate 80 policy-relevant research questions considered by participants to have the greatest impact on UK biological security. Drawing on a collaboratively-developed set of 450 questions, proposed by 41 experts from academia, industry and the UK government (consulting 168 additional experts) we subdivided the final 80 questions into six categories: bioengineering; communication and behaviour; disease threats (including pandemics); governance and policy; invasive alien species; and securing biological materials and securing against misuse. Initially, the questions were ranked through a voting process and then reduced and refined to 80 during a one-day workshop with 35 participants from a variety of disciplines. Consistently emerging themes included: the nature of current and potential biological security threats, the efficacy of existing management actions, and the most appropriate future options. The resulting questions offer a research agenda for biological security in the UK that can assist the targeting of research resources and inform the implementation of the UK Biological Security Strategy. These questions include research that could aid with the mitigation of Covid-19, and preparation for the next pandemic. We hope that our structured and rigorous approach to creating a biological security research agenda will be replicated in other countries and regions. The world, not just the UK, is in need of a thoughtful approach to directing biological security research to tackle the emerging issues.


Assuntos
Pandemias/prevenção & controle , Medidas de Segurança/tendências , Bioterrorismo/prevenção & controle , Governança Clínica/tendências , Comunicação , Transmissão de Doença Infecciosa/prevenção & controle , Transmissão de Doença Infecciosa/estatística & dados numéricos , Humanos , Pandemias/estatística & dados numéricos , Políticas , Medidas de Segurança/estatística & dados numéricos , Inquéritos e Questionários , Reino Unido/epidemiologia
3.
Am J Otolaryngol ; 42(1): 102829, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33186853

RESUMO

PURPOSE: The COVID-19 pandemic has led to concerns over transmission risk from healthcare procedures, especially when operating in the head and neck such as during surgical repair of facial fractures. This study aims to quantify aerosol and droplet generation from mandibular and midface open fixation and measure mitigation of airborne particles by a smoke evacuating electrocautery hand piece. MATERIALS AND METHODS: The soft tissue of the bilateral mandible and midface of two fresh frozen cadaveric specimens was infiltrated using a 0.1% fluorescein solution. Surgical fixation via oral vestibular approach was performed on each of these sites. Droplet splatter on the surgeon's chest, facemask, and up to 198.12 cm (6.5 ft) away from each surgical site was measured against a blue background under ultraviolet-A (UV-A) light. Aerosol generation was measured using an optical particle sizer. RESULTS: No visible droplet contamination was observed for any trials of mandible or midface fixation. Total aerosolized particle counts from 0.300-10.000 µm were increased compared to baseline following each use of standard electrocautery (n = 4, p < 0.001) but not with use of a suction evacuating electrocautery hand piece (n = 4, p = 0.103). Total particle counts were also increased during use of the powered drill (n = 8, p < 0.001). CONCLUSIONS: Risk from visible droplets during mandible and midface fixation is low. However, significant increases in aerosolized particles were measured after electrocautery use and during powered drilling. Aerosol dispersion is significantly decreased with the use of a smoke evacuating electrocautery hand piece.


Assuntos
Aerossóis/efeitos adversos , Transmissão de Doença Infecciosa/estatística & dados numéricos , Período Intraoperatório , Pandemias , /epidemiologia , Humanos , Mandíbula , Estados Unidos/epidemiologia
4.
Front Public Health ; 8: 609974, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33344408

RESUMO

Background: COVID-19 developed into a global pandemic in 2020 and poses challenges regarding the prevention and control capabilities of countries. A large number of inbound travelers from other regions could lead to a renewed outbreak of COVID-19 in the local regions. Globally, as a result of the imbalance in the control of the epidemic, all countries are facing the risk of a renewed COVID-19 outbreak brought about by travelers from epidemic areas. Therefore, studies on a proper management of the inbound travelers are urgent. Methods: We collected a total of 4,733,414 inbound travelers and 174 COVID-19 diagnosed patients in Yunnan province from 21 January 2020 to 20 February 2020. Data on place of origin, travel history, age, and gender, as well as whether they had suspected clinical manifestations for inbound travelers in Yunnan were collected. The impact of inbound travelers on the local epidemic was analyzed with a collinear statistical analysis and the effect of the control measures on the epidemic was evaluated with a sophisticated modeling approach. Results: Of the 174 COVID-19 patients, 60.9% were not from Yunnan, and 76.4% had a history of travel in Hubei. The amount of new daily cases in Yunnan was significant correlated with the number of inbound travelers from Hubei and suspected cases among them. Using Susceptible-Exposed-Infectious-Recovered (SEIR) model analysis, we found that the prevention and control measures dropped the local R0 down to 1.07 in Yunnan province. Conclusions: Our preliminary analysis showed that the proper management of inbound travelers from outbreak areas has a significantly positive effect on the prevention and control of the virus. In the process of resettlement, some effective measures taken by Yunnan province may provide an important reference for preventing the renewed COVID-19 outbreak in other regions.


Assuntos
/transmissão , Surtos de Doenças/prevenção & controle , Surtos de Doenças/estatística & dados numéricos , Transmissão de Doença Infecciosa/prevenção & controle , Pandemias/prevenção & controle , Pandemias/estatística & dados numéricos , Viagem/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Transmissão de Doença Infecciosa/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
Ann Acad Med Singap ; 49(11): 857-869, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33381779

RESUMO

INTRODUCTION: Pregnant women are reported to be at increased risk of severe coronavirus disease 2019 (COVID-19) due to underlying immunosuppression during pregnancy. However, the clinical course of COVID-19 in pregnancy and risk of vertical and horizontal transmission remain relatively unknown. We aim to describe and evaluate outcomes in pregnant women with COVID-19 in Singapore. METHODS: Prospective observational study of 16 pregnant patients admitted for COVID-19 to 4 tertiary hospitals in Singapore. Outcomes included severe disease, pregnancy loss, and vertical and horizontal transmission. RESULTS: Of the 16 patients, 37.5%, 43.8% and 18.7% were infected in the first, second and third trimesters, respectively. Two gravidas aged ≥35 years (12.5%) developed severe pneumonia; one patient (body mass index 32.9kg/m2) required transfer to intensive care. The median duration of acute infection was 19 days; one patient remained reverse transcription polymerase chain reaction (RT-PCR) positive >11 weeks from diagnosis. There were no maternal mortalities. Five pregnancies produced term live-births while 2 spontaneous miscarriages occurred at 11 and 23 weeks. RT-PCR of breast milk and maternal and neonatal samples taken at birth were negative; placenta and cord histology showed non-specific inflammation; and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific immunoglobulins were elevated in paired maternal and umbilical cord blood (n=5). CONCLUSION: The majority of COVID-19 infected pregnant women had mild disease and only 2 women with risk factors (obesity, older age) had severe infection; this represents a slightly higher incidence than observed in age-matched non-pregnant women. Among the women who delivered, there was no definitive evidence of mother-to-child transmission via breast milk or placenta.


Assuntos
/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Aborto Espontâneo/epidemiologia , Adulto , /transmissão , Estudos de Coortes , Transmissão de Doença Infecciosa/estatística & dados numéricos , Feminino , Sangue Fetal/imunologia , Humanos , Transmissão Vertical de Doença Infecciosa/estatística & dados numéricos , Nascimento Vivo/epidemiologia , Idade Materna , Leite Humano/química , Leite Humano/virologia , Obesidade Materna/epidemiologia , Placenta/patologia , Gravidez , Complicações Infecciosas na Gravidez/fisiopatologia , Primeiro Trimestre da Gravidez , Segundo Trimestre da Gravidez , Estudos Prospectivos , RNA Viral/análise , Fatores de Risco , Índice de Gravidade de Doença , Singapura/epidemiologia , Cordão Umbilical/patologia , Adulto Jovem
6.
Medicine (Baltimore) ; 99(47): e23319, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33217869

RESUMO

An ongoing outbreak of Coronavirus Disease 2019 (COVID-19) has spread around the world. However, the clinical characteristics and outcomes of patients with COVID-19 related to different modes of exposure have not been well defined. We aimed to explore the clinical features and outcomes of COVID-19 related to one-time community exposure versus continuous household exposure.Retrospective case-control study involving COVID-19 patients admitted to a tertiary designated center in China was performed. Patients were enrolled if they had known exposure history of one-time community exposure or continuous household exposure. Twenty patients were compared in terms of demographic characteristics, clinical presentation, chest CT images, laboratory results, treatments, and clinical outcomes at 1-month follow-up.There were 10 patients in one-time community and continuous household exposure groups respectively. Males compromised 80% and 40% while the median ages were 37.5 and 51 years old in the 2 groups, respectively. Fever and cough were most common symptoms. Ground-glass opacities were presented on chest CT scan in 90% and 70% of the patients, and the median CT scores were 7 and 16 on admission, respectively. Three patients ranked severe in the community exposure group while 7 patients were severe or critical in household exposure group. On 1-month follow-up, all patients were improved clinically but COVID-19 IgG antibody detected positive. Median follow-up CT scores were 0 and 13 while pulmonary function test abnormalities were 0/9 and 2/7 in the 2 groups, respectively.COVID-19 patients with one-time community exposure tended to be mild in severity and had better outcomes, comparing to those with continuous household exposure.


Assuntos
Betacoronavirus , Infecções por Coronavirus/patologia , Transmissão de Doença Infecciosa/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Pneumonia Viral/patologia , Índice de Gravidade de Doença , Adulto , Estudos de Casos e Controles , China/epidemiologia , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/transmissão , Notificação de Doenças , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Pulmão/virologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/mortalidade , Pneumonia Viral/transmissão , Estudos Retrospectivos
7.
Br J Hosp Med (Lond) ; 81(10): 1-9, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33135928

RESUMO

After initially emerging in late 2019, coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread rapidly to cause a global pandemic. SARS-CoV-2 is a betacoronavirus that is closely related to severe acute respiratory syndrome coronavirus and Middle East respiratory syndrome coronavirus, all of which can cause severe lung injury, respiratory distress and cytokine storm. While mortality rates associated with SARS-CoV-2 are lower than those associated with severe acute respiratory syndrome coronavirus or Middle East respiratory syndrome coronavirus, it is more contagious and spreads more rapidly than these other viruses. This article summarises the epidemiology and potential options for treating COVID-19 to give a foundation for future studies of the diagnosis, treatment and prevention of this deadly disease.


Assuntos
Betacoronavirus , Controle de Doenças Transmissíveis/métodos , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Betacoronavirus/isolamento & purificação , Betacoronavirus/patogenicidade , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/terapia , Infecções por Coronavirus/transmissão , Transmissão de Doença Infecciosa/prevenção & controle , Transmissão de Doença Infecciosa/estatística & dados numéricos , Saúde Global/estatística & dados numéricos , Humanos , Pandemias/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/terapia , Pneumonia Viral/transmissão
8.
PLoS One ; 15(10): e0238186, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33057348

RESUMO

Mathematical models are powerful tools to investigate, simulate, and evaluate potential interventions for infectious diseases dynamics. Much effort has focused on the Susceptible-Infected-Recovered (SIR)-type compartment models. These models consider host populations and measure change of each compartment. In this study, we propose an alternative patch dynamic modeling framework from pathogens' perspective. Each patch, the basic module of this modeling framework, has four standard mechanisms of pathogen population size change: birth (replication), death, inflow, and outflow. This framework naturally distinguishes between-host transmission process (inflow and outflow) and within-host infection process (replication) during the entire transmission-infection cycle. We demonstrate that the SIR-type model is actually a special cross-sectional and discretized case of our patch dynamics model in pathogens' viewpoint. In addition, this patch dynamics modeling framework is also an agent-based model from hosts' perspective by incorporating individual host's specific traits. We provide an operational standard to formulate this modular-designed patch dynamics model. Model parameterization is feasible with a wide range of sources, including genomics data, surveillance data, electronic health record, and from other emerging technologies such as multiomics. We then provide two proof-of-concept case studies to tackle some of the existing challenges of SIR-type models: sexually transmitted disease and healthcare acquired infections. This patch dynamics modeling framework not only provides theoretical explanations to known phenomena, but also generates novel insights of disease dynamics from a more holistic viewpoint. It is also able to simulate and handle more complicated scenarios across biological scales such as the current COVID-19 pandemic.


Assuntos
Doenças Transmissíveis/epidemiologia , Transmissão de Doença Infecciosa/estatística & dados numéricos , Modelos Teóricos , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Infecções Bacterianas/transmissão , Doenças Transmissíveis/transmissão , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Humanos , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia
9.
Emerg Infect Dis ; 26(11): 2598-2606, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33035448

RESUMO

We report the transmission dynamics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) across different settings in Brunei. An initial cluster of SARS-CoV-2 cases arose from 19 persons who had attended the Tablighi Jama'at gathering in Malaysia, resulting in 52 locally transmitted cases. The highest nonprimary attack rates (14.8%) were observed from a subsequent religious gathering in Brunei and in households of attendees (10.6%). Household attack rates from symptomatic case-patients were higher (14.4%) than from asymptomatic (4.4%) or presymptomatic (6.1%) case-patients. Workplace and social settings had attack rates of <1%. Our analyses highlight that transmission of SARS-CoV-2 varies depending on environmental, behavioral, and host factors. We identify red flags for potential superspreading events, specifically densely populated gatherings with prolonged exposure in enclosed settings, persons with recent travel history to areas with active SARS-CoV-2 infections, and group behaviors. We propose differentiated testing strategies to account for differing transmission risk.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Transmissão de Doença Infecciosa/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Adulto , Idoso , Brunei/epidemiologia , Técnicas de Laboratório Clínico/estatística & dados numéricos , Análise por Conglomerados , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/transmissão , Feminino , Humanos , Malásia/epidemiologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/transmissão , Doença Relacionada a Viagens
11.
J Glob Health ; 10(2): 020501, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33110584

RESUMO

Background: The focus of the study is to assess the role of different transport means in the importation and diffusion of 1918-19 influenza and a novel 2019 corona virus designated as COVID-19 in Nigeria. Methods: The study provides a review of the means by which the two pandemics were imported into the country and the roles the transport means of each period played in the local spread of the epidemics. Results: The study notes that seaports and railways, being the emerging transportation modes in the country were significant to the importation and local diffusion of 1918-19 influenza, respectively, while air transport is significant to the importation of the current COVID-19 pandemic. Conclusions: The study concludes that increasing preference for the transport at a given epoch is significant to the diffusion of prevailing epidemic in the epoch.


Assuntos
Infecções por Coronavirus/epidemiologia , Transmissão de Doença Infecciosa/estatística & dados numéricos , Influenza Pandêmica, 1918-1919/estatística & dados numéricos , Pandemias/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Transportes/estatística & dados numéricos , Betacoronavirus , Infecções por Coronavirus/transmissão , Transmissão de Doença Infecciosa/história , História do Século XX , História do Século XXI , Humanos , Nigéria/epidemiologia , Pandemias/história , Pneumonia Viral/transmissão , Transportes/história
12.
BMJ ; 371: m3588, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028597

RESUMO

OBJECTIVE: To replicate and analyse the information available to UK policymakers when the lockdown decision was taken in March 2020 in the United Kingdom. DESIGN: Independent calculations using the CovidSim code, which implements Imperial College London's individual based model, with data available in March 2020 applied to the coronavirus disease 2019 (covid-19) epidemic. SETTING: Simulations considering the spread of covid-19 in Great Britain and Northern Ireland. POPULATION: About 70 million simulated people matched as closely as possible to actual UK demographics, geography, and social behaviours. MAIN OUTCOME MEASURES: Replication of summary data on the covid-19 epidemic reported to the UK government Scientific Advisory Group for Emergencies (SAGE), and a detailed study of unpublished results, especially the effect of school closures. RESULTS: The CovidSim model would have produced a good forecast of the subsequent data if initialised with a reproduction number of about 3.5 for covid-19. The model predicted that school closures and isolation of younger people would increase the total number of deaths, albeit postponed to a second and subsequent waves. The findings of this study suggest that prompt interventions were shown to be highly effective at reducing peak demand for intensive care unit (ICU) beds but also prolong the epidemic, in some cases resulting in more deaths long term. This happens because covid-19 related mortality is highly skewed towards older age groups. In the absence of an effective vaccination programme, none of the proposed mitigation strategies in the UK would reduce the predicted total number of deaths below 200 000. CONCLUSIONS: It was predicted in March 2020 that in response to covid-19 a broad lockdown, as opposed to a focus on shielding the most vulnerable members of society, would reduce immediate demand for ICU beds at the cost of more deaths long term. The optimal strategy for saving lives in a covid-19 epidemic is different from that anticipated for an influenza epidemic with a different mortality age profile.


Assuntos
Infecções por Coronavirus/mortalidade , Transmissão de Doença Infecciosa/estatística & dados numéricos , Previsões , Pneumonia Viral/mortalidade , Quarentena/tendências , Instituições Acadêmicas/organização & administração , Betacoronavirus , Simulação por Computador , Infecções por Coronavirus/transmissão , Feminino , Humanos , Unidades de Terapia Intensiva/tendências , Masculino , Irlanda do Norte/epidemiologia , Pandemias , Pneumonia Viral/transmissão , Quarentena/métodos , Reino Unido/epidemiologia
13.
Acta Med Indones ; 52(3): 206-213, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33020332

RESUMO

BACKGROUND: COVID-19 infection is caused by a novel coronavirus. One of the most used strategies that can be used to control the spread of COVID-19 is the 3T (test, trace, and treatment) strategy. This study aimed to evaluate the 3T strategy to control COVID-19 infection in a COVID-19 Referral Hospital in Depok, West Java, Indonesia. METHODS: this is a cross-sectional study conducted at the University of Indonesia Hospital. The study was conducted in June 2020 with 742 participants (staff members) using secondary data from polymerase chain reaction (PCR) test results. We presented data in the descriptive form and performed bivariate analysis using the chi-square/Fischer test for categorical data. RESULTS: the PCR test results were positive in 83 (11.1%) participants, with a case-per-tracing ratio of 1:24 and 1:2 in the first and third phases of tracing, respectively. The COVID-19 case graph for the participants decreased along with the implementation of the 3T strategy. The positivity rate in the first phase of tracing was 20% and decreased to 5% in the third phase of tracing. Staff with confirmed positive test results were advised to isolate themselves (hospital or self-isolation). Hospital isolation was found to be associated with the duration of PCR test conversion (p<0.001). CONCLUSION: the 3T strategy is effective for controlling the spread of COVID-19. The strategy should be implemented simultaneously with other health precautions to reduce the risk of spreading infection.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/diagnóstico , DNA Viral/análise , Transmissão de Doença Infecciosa/estatística & dados numéricos , Pandemias , Recursos Humanos em Hospital/estatística & dados numéricos , Pneumonia Viral/diagnóstico , Adulto , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Estudos Transversais , Feminino , Humanos , Indonésia/epidemiologia , Masculino , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Estudos Retrospectivos
14.
PLoS One ; 15(9): e0239809, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32991628

RESUMO

The Chinese poultry industry has experienced outbreaks of Newcastle disease (ND) dating back to the 1920s. However, the epidemic has exhibited a downtrend in recent years. In this study, both observational and genetic data [fusion (F) and haemagglutinin-neuraminidase genes (HN)] were analyzed, and phylogeographic analysis based on prevalent genotypes of Newcastle disease virus (NDV) was conducted for better understanding of the evolution and spatiotemporal dynamics of ND in China. In line with the observed trend of epidemic outbreaks, the effective population size of F and HN genes of circulating NDV is no longer growing since 2000, which is supported by 95% highest posterior diversity (HPD) intervals. Phylogeographic analysis indicated that the two eastern coastal provinces, Shandong and Jiangsu were the most relevant hubs for NDV migration, and the geographical regions with active NDV diffusion seemed to be constrained to southern and eastern China. The live poultry trade may play an important role in viral spread. Interestingly, no migration links from wild birds to poultry received Bayes factor support (BF > 3), while the migration links from poultry to wild birds accounted for 64% in all effective migrations. This may indicate that the sporadic cases of ND in wild bird likely spillover events from poultry. These findings contribute to predictive models of NDV transmission, and potentially help in the prevention of future outbreaks.


Assuntos
Transmissão de Doença Infecciosa/veterinária , Evolução Molecular , Doença de Newcastle/epidemiologia , Vírus da Doença de Newcastle/genética , Migração Animal , Animais , Teorema de Bayes , China , Surtos de Doenças , Transmissão de Doença Infecciosa/estatística & dados numéricos , Genótipo , Proteína HN/genética , Doença de Newcastle/transmissão , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/classificação , Vírus da Doença de Newcastle/patogenicidade , Filogenia , Filogeografia , Aves Domésticas
15.
Emerg Infect Dis ; 26(11): e1-e14, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917290

RESUMO

We report key epidemiologic parameter estimates for coronavirus disease identified in peer-reviewed publications, preprint articles, and online reports. Range estimates for incubation period were 1.8-6.9 days, serial interval 4.0-7.5 days, and doubling time 2.3-7.4 days. The effective reproductive number varied widely, with reductions attributable to interventions. Case burden and infection fatality ratios increased with patient age. Implementation of combined interventions could reduce cases and delay epidemic peak up to 1 month. These parameters for transmission, disease severity, and intervention effectiveness are critical for guiding policy decisions. Estimates will likely change as new information becomes available.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Transmissão de Doença Infecciosa/estatística & dados numéricos , Modelos Estatísticos , Modelos Teóricos , Pneumonia Viral/epidemiologia , Infecções por Coronavirus/transmissão , Humanos , Pandemias , Pneumonia Viral/transmissão
16.
Emerg Infect Dis ; 26(11): 2713-2716, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32946370

RESUMO

Four persons with severe acute respiratory syndrome coronavirus 2 infection had traveled on the same flight from Boston, Massachusetts, USA, to Hong Kong, China. Their virus genetic sequences are identical, unique, and belong to a clade not previously identified in Hong Kong, which strongly suggests that the virus can be transmitted during air travel.


Assuntos
Viagem Aérea , Betacoronavirus , Infecções por Coronavirus/transmissão , Transmissão de Doença Infecciosa/estatística & dados numéricos , Pneumonia Viral/transmissão , Doença Relacionada a Viagens , Adulto , Idoso , Boston/epidemiologia , Infecções por Coronavirus/epidemiologia , Feminino , Hong Kong/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/epidemiologia
17.
Emerg Infect Dis ; 26(11): 2617-2624, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32946369

RESUMO

To assess the role of in-flight transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), we investigated a cluster of cases among passengers on a 10-hour commercial flight. Affected persons were passengers, crew, and their close contacts. We traced 217 passengers and crew to their final destinations and interviewed, tested, and quarantined them. Among the 16 persons in whom SARS-CoV-2 infection was detected, 12 (75%) were passengers seated in business class along with the only symptomatic person (attack rate 62%). Seating proximity was strongly associated with increased infection risk (risk ratio 7.3, 95% CI 1.2-46.2). We found no strong evidence supporting alternative transmission scenarios. In-flight transmission that probably originated from 1 symptomatic passenger caused a large cluster of cases during a long flight. Guidelines for preventing SARS-CoV-2 infection among air passengers should consider individual passengers' risk for infection, the number of passengers traveling, and flight duration.


Assuntos
Viagem Aérea , Betacoronavirus , Infecções por Coronavirus/transmissão , Transmissão de Doença Infecciosa/estatística & dados numéricos , Pneumonia Viral/transmissão , Quarentena/estatística & dados numéricos , Adulto , Idoso , Aeronaves , Análise por Conglomerados , Busca de Comunicante/estatística & dados numéricos , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Transmissão de Doença Infecciosa/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Pandemias/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle
18.
Intern Emerg Med ; 15(8): 1545-1552, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32948990

RESUMO

In a Coronavirus disease 2019 (COVID-19) epidemic, management of the emergency department is a difficult task in terms of prevention and control of the disease in general hospitals. On top of meeting urgent needs of patients for medical treatment, the emergency department also has to devote resources into investigation and prevention of COVID-19. At the beginning of the epidemic, with the strategy to intercept the chain of infection, Peking University First Hospital (PKUFH) focused on three important aspects: controlling the source of infection, cutting off the route of transmission, and protecting vulnerable populations, to expeditiously draft scientific and proper management measures for the emergency department, followed by real-time dynamic adjustments based on the development trend of the epidemic. These measures effectively ensured a smooth, orderly and safe operation of the emergency department. As of the writing of this manuscript, there has been no active COVID-19 infection in patients and medical staff in the emergency department, and no infection in patients admitted to PKUFH through the emergency department. This study describes the prevention and control measures in the emergency department of PKUFH during the outbreak of COVID-19, aiming to provide some reference for domestic and international medical institutions.


Assuntos
Gerenciamento Clínico , Transmissão de Doença Infecciosa/prevenção & controle , Serviço Hospitalar de Emergência/estatística & dados numéricos , Absenteísmo , Transmissão de Doença Infecciosa/estatística & dados numéricos , Educação Continuada/métodos , Serviço Hospitalar de Emergência/organização & administração , Hospitais Gerais/organização & administração , Hospitais Gerais/estatística & dados numéricos , Humanos , Controle de Infecções/métodos , Controle de Infecções/normas , Controle de Infecções/tendências , Pandemias/prevenção & controle , Pandemias/estatística & dados numéricos , Admissão e Escalonamento de Pessoal/tendências , Inquéritos e Questionários
19.
Sensors (Basel) ; 20(17)2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32887338

RESUMO

COVID-19 has shown a relatively low case fatality rate in young healthy individuals, with the majority of this group being asymptomatic or having mild symptoms. However, the severity of the disease among the elderly as well as in individuals with underlying health conditions has caused significant mortality rates worldwide. Understanding this variance amongst different sectors of society and modelling this will enable the different levels of risk to be determined to enable strategies to be applied to different groups. Long-established compartmental epidemiological models like SIR and SEIR do not account for the variability encountered in the severity of the SARS-CoV-2 disease across different population groups. The objective of this study is to investigate how a reduction in the exposure of vulnerable individuals to COVID-19 can minimise the number of deaths caused by the disease, using the UK as a case study. To overcome the limitation of long-established compartmental epidemiological models, it is proposed that a modified model, namely SEIR-v, through which the population is separated into two groups regarding their vulnerability to SARS-CoV-2 is applied. This enables the analysis of the spread of the epidemic when different contention measures are applied to different groups in society regarding their vulnerability to the disease. A Monte Carlo simulation (100,000 runs) along the proposed SEIR-v model is used to study the number of deaths which could be avoided as a function of the decrease in the exposure of vulnerable individuals to the disease. The results indicate a large number of deaths could be avoided by a slight realistic decrease in the exposure of vulnerable groups to the disease. The mean values across the simulations indicate 3681 and 7460 lives could be saved when such exposure is reduced by 10% and 20% respectively. From the encouraging results of the modelling a number of mechanisms are proposed to limit the exposure of vulnerable individuals to the disease. One option could be the provision of a wristband to vulnerable people and those without a smartphone and contact-tracing app, filling the gap created by systems relying on smartphone apps only. By combining very dense contact tracing data from smartphone apps and wristband signals with information about infection status and symptoms, vulnerable people can be protected and kept safer.


Assuntos
Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Transmissão de Doença Infecciosa/estatística & dados numéricos , Modelos Teóricos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Saúde Pública/métodos , Quarentena/organização & administração , Populações Vulneráveis , Busca de Comunicante/métodos , Infecções por Coronavirus/epidemiologia , Surtos de Doenças/prevenção & controle , Diretrizes para o Planejamento em Saúde , Necessidades e Demandas de Serviços de Saúde , Humanos , Controle de Infecções/métodos , Controle de Infecções/organização & administração , Controle de Infecções/estatística & dados numéricos , Invenções/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Serviços Preventivos de Saúde/métodos , Serviços Preventivos de Saúde/organização & administração , Serviços Preventivos de Saúde/normas , Saúde Pública/estatística & dados numéricos , Administração em Saúde Pública/métodos , Quarentena/métodos , Quarentena/estatística & dados numéricos , Reino Unido/epidemiologia , Populações Vulneráveis/estatística & dados numéricos
20.
Prev Chronic Dis ; 17: E109, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32945766

RESUMO

INTRODUCTION: In response to the coronavirus disease 2019 (COVID-19) pandemic, New York City closed all nonessential businesses and restricted the out-of-home activities of residents as of March 22, 2020. This order affected different neighborhoods differently, as stores and workplaces are not randomly distributed across the city, and different populations may have responded differently to the out-of-home restrictions. This study examines how the business closures and activity restrictions affected COVID-19 testing results. An evaluation of whether such actions slowed the spread of the pandemic is a crucial step in designing effective public health policies. METHODS: Daily data on the fraction of COVID-19 tests yielding a positive result at the zip code level were analyzed in relation to the number of visits to local businesses (based on smartphone location) and the number of smartphones that stayed fixed at their home location. The regression model also included vectors of fixed effects for the day of the week, the calendar date, and the zip code of residence. RESULTS: A large number of visits to local businesses increased the positivity rate of COVID-19 tests, while a large number of smartphones that stayed at home decreased it. A doubling in the relative number of visits increases the positivity rate by about 12.4 percentage points (95% CI, 5.3 to 19.6). A doubling in the relative number of stay-at-home devices lowered it by 2.0 percentage points (95% CI, -2.9 to -1.2). The business closures and out-of-home activity restrictions decreased the positivity rate, accounting for approximately 25% of the decline observed in April and May 2020. CONCLUSION: Policy measures decreased the likelihood of positive results in COVID-19 tests. These specific policy tools may be successfully used when comparable health crises arise in the future.


Assuntos
Betacoronavirus/isolamento & purificação , Técnicas de Laboratório Clínico , Comércio/legislação & jurisprudência , Controle de Doenças Transmissíveis , Infecções por Coronavirus , Transmissão de Doença Infecciosa , Pandemias , Pneumonia Viral , Técnicas de Laboratório Clínico/métodos , Técnicas de Laboratório Clínico/estatística & dados numéricos , Controle de Doenças Transmissíveis/instrumentação , Controle de Doenças Transmissíveis/métodos , Controle de Doenças Transmissíveis/estatística & dados numéricos , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Transmissão de Doença Infecciosa/prevenção & controle , Transmissão de Doença Infecciosa/estatística & dados numéricos , Humanos , Cidade de Nova Iorque/epidemiologia , Pandemias/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Formulação de Políticas , Gestão da Saúde da População , Saúde Pública/métodos , Saúde Pública/estatística & dados numéricos , Medição de Risco/métodos , Smartphone/estatística & dados numéricos , Distância Social
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