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Magnolia Cardona

Bio: Magnolia Cardona is an academic researcher from Bond University. The author has contributed to research in topics: Medicine & Health care. The author has an hindex of 13, co-authored 41 publications receiving 1396 citations. Previous affiliations of Magnolia Cardona include University of Sydney & National Health and Medical Research Council.

Papers published on a yearly basis

Papers
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Journal ArticleDOI
11 Dec 2020
TL;DR: This work synthesizes all known cases of true asymptomatic coronavirus disease 2019 (COVID-19) and aims to synthesize all known avian influenza A viruses to help design mitigation measures against the pandemic.
Abstract: Background: Knowing the prevalence of true asymptomatic coronavirus disease 2019 (COVID-19) cases is critical for designing mitigation measures against the pandemic. We aimed to synthesize all avai...

532 citations

Journal ArticleDOI
TL;DR: Non-communicable and chronic diseases are the leading causes of death in this part of rural India and provides new insight into the rapid progression of epidemiological transition in rural India.
Abstract: Introduction: India is undergoing rapid epidemiological transition as a consequence of economic and social change. The pattern of mortality is a key indicator of the consequent health effects but up-to-date, precise, and reliable statistics are few, particularly in rural areas. Methods: Deaths occurring in 45 villages (population 180 162) were documented during a 12-month period in 2003-04 by multipurpose primary healthcare workers trained in the use of a verbal autopsy tool. Algorithms were used to define causes of death according to a limited list derived from the international classification of disease version 10. Causes were assigned by two independent physicians with disagreements resolved by a third. Results: A total of 1354 deaths were recorded with verbal autopsies completed for 98%. A specific underlying cause of death was assigned for 82% of all verbal autopsies done. The crude death rate was 7.5/1000 (95% confidence interval, 7.1-7.9). Diseases of the circulatory system were the leading causes of mortality (32%), with similar proportions of deaths attributable to ischaemic heart disease and stroke. Second was injury and external causes of mortality (13%) with one-third of these deaths attributable to deliberate self harm. Third were infectious and parasitic diseases (12%). Tuberculosis and intestinal conditions each caused one-third of deaths within this category. HIV was assigned as the cause for 2% of all deaths. The fourth and fifth leading causes of death were neoplasms (7%) and diseases of the respiratory system (5%). Conclusion: Non-communicable and chronic diseases are the leading causes of death in this part of rural India. The observed pattern of death is unlikely to be unique to these villages and provides new insight into the rapid progression of epidemiological transition in rural India.

308 citations

Journal ArticleDOI
TL;DR: Very high levels of diabetes have been reported in urban areas of India, but few data are available for rural regions where >70% of the population lives, suggesting rural India may soon experience the same epidemic of diabetes.
Abstract: Very high levels of diabetes have been reported in urban areas of India (1), but few data are available for rural regions where >70% of the population lives. Data from a new large-scale survey done in 2005 suggest rural India may soon experience the same epidemic of diabetes. A total of 4,535 individuals aged ≥30 years (response rate 81%, mean age 46.8 years) were sampled at random age and sex strata from 20 villages representative of Godavari, a developing rural area of Andhra Pradesh. Data were collected using a structured questionnaire and a …

143 citations

Posted ContentDOI
04 Jun 2020-medRxiv
TL;DR: Estimates of the prevalence of asymptomatic COVID-19 cases are lower than many highly publicized studies, but still substantial; further robust epidemiological evidence is urgently needed, including in sub-populations such as children, to better understand the importance of asylptomatic cases for driving spread of the pandemic.
Abstract: Background The prevalence of true asymptomatic COVID-19 cases is critical to policy makers considering the effectiveness of mitigation measures against the SARS-CoV-2 pandemic. We aimed to synthesize all available research on the asymptomatic rates and transmission rates where possible. Methods We searched PubMed, Embase, Cochrane COVID-19 trials, and Europe PMC (which covers pre-print platforms such as MedRxiv). We included primary studies reporting on asymptomatic prevalence where: (a) the sample frame includes at-risk population, and (b) there was sufficiently long follow up to identify pre-symptomatic cases. Meta-analysis used fixed effect and random effects models. We assessed risk of bias by combination of questions adapted from risk of bias tools for prevalence and diagnostic accuracy studies. Results We screened 998 articles and included nine low risk-of-bias studies from six countries that tested 21,035 at-risk people, of which 559 were positive and 83 were asymptomatic. Diagnosis in all studies was confirmed using a RT-qPCR test. The proportion of asymptomatic cases ranged from 4% to 41%. Meta-analysis (fixed effect) found that the proportion of asymptomatic cases was 15% (95% CI: 12% - 18%) overall; higher in non-aged care 16% (13% - 19%), and lower in long-term aged care 8% (3% - 18%). Four studies provided direct evidence of forward transmission of the infection by asymptomatic cases but suggested considerably lower rates than symptomatic cases. Discussion Our estimates of the prevalence of asymptomatic COVID-19 cases and asymptomatic transmission rates are lower than many highly publicized studies, but still sufficient to warrant policy attention. Further robust epidemiological evidence is urgently needed, including in sub-populations such as children, to better understand the importance of asymptomatic cases for driving spread of the pandemic. Funding OB is supported by NHMRC Grant APP1106452. PG is supported by NHMRC Australian Fellowship grant 1080042. KB was supported by NHMRC Fellowship grant 1174523. All authors had full access to all data and agreed to final manuscript to be submitted for publication. There was no funding source for this study.

133 citations

Journal ArticleDOI
TL;DR: The possibility of increasing cardiovascular risk factors and prevalence of vascular disease in areas of rural India represent a public health concern and larger and repeated epidemiological studies focusing on chronic diseases are required to inform treatment and prevention strategies suitable for use in these areas and other resource poor settings.

92 citations


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Journal ArticleDOI
25 Aug 2020-JAMA
TL;DR: This review discusses current evidence regarding the pathophysiology, transmission, diagnosis, and management of COVID-19, the novel severe acute respiratory syndrome coronavirus 2 pandemic that has caused a worldwide sudden and substantial increase in hospitalizations for pneumonia with multiorgan disease.
Abstract: Importance The coronavirus disease 2019 (COVID-19) pandemic, due to the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused a worldwide sudden and substantial increase in hospitalizations for pneumonia with multiorgan disease. This review discusses current evidence regarding the pathophysiology, transmission, diagnosis, and management of COVID-19. Observations SARS-CoV-2 is spread primarily via respiratory droplets during close face-to-face contact. Infection can be spread by asymptomatic, presymptomatic, and symptomatic carriers. The average time from exposure to symptom onset is 5 days, and 97.5% of people who develop symptoms do so within 11.5 days. The most common symptoms are fever, dry cough, and shortness of breath. Radiographic and laboratory abnormalities, such as lymphopenia and elevated lactate dehydrogenase, are common, but nonspecific. Diagnosis is made by detection of SARS-CoV-2 via reverse transcription polymerase chain reaction testing, although false-negative test results may occur in up to 20% to 67% of patients; however, this is dependent on the quality and timing of testing. Manifestations of COVID-19 include asymptomatic carriers and fulminant disease characterized by sepsis and acute respiratory failure. Approximately 5% of patients with COVID-19, and 20% of those hospitalized, experience severe symptoms necessitating intensive care. More than 75% of patients hospitalized with COVID-19 require supplemental oxygen. Treatment for individuals with COVID-19 includes best practices for supportive management of acute hypoxic respiratory failure. Emerging data indicate that dexamethasone therapy reduces 28-day mortality in patients requiring supplemental oxygen compared with usual care (21.6% vs 24.6%; age-adjusted rate ratio, 0.83 [95% CI, 0.74-0.92]) and that remdesivir improves time to recovery (hospital discharge or no supplemental oxygen requirement) from 15 to 11 days. In a randomized trial of 103 patients with COVID-19, convalescent plasma did not shorten time to recovery. Ongoing trials are testing antiviral therapies, immune modulators, and anticoagulants. The case-fatality rate for COVID-19 varies markedly by age, ranging from 0.3 deaths per 1000 cases among patients aged 5 to 17 years to 304.9 deaths per 1000 cases among patients aged 85 years or older in the US. Among patients hospitalized in the intensive care unit, the case fatality is up to 40%. At least 120 SARS-CoV-2 vaccines are under development. Until an effective vaccine is available, the primary methods to reduce spread are face masks, social distancing, and contact tracing. Monoclonal antibodies and hyperimmune globulin may provide additional preventive strategies. Conclusions and Relevance As of July 1, 2020, more than 10 million people worldwide had been infected with SARS-CoV-2. Many aspects of transmission, infection, and treatment remain unclear. Advances in prevention and effective management of COVID-19 will require basic and clinical investigation and public health and clinical interventions.

3,371 citations

Journal ArticleDOI
Marina Pollán1, Beatriz Pérez-Gómez1, Roberto Pastor-Barriuso1, Jesús Oteo1, Miguel A. Hernán2, Miguel A. Hernán3, Mayte Pérez-Olmeda1, Jose L Sanmartín, Aurora Fernández-García1, Aurora Fernández-García4, Israel Cruz1, Nerea Fernández de Larrea1, Marta Molina, Francisco Rodríguez-Cabrera1, Mariano Martín, Paloma Merino-Amador4, Jose León Paniagua1, Juan F Muñoz-Montalvo, Faustino Blanco, Raquel Yotti1, Rodrigo Gutiérrez Fernández, Saturnino Mezcua Navarro, Matías Salinero Hernández, Manuel Cuenca-Estrella, Pablo Fernández-Navarro, Ana Avellón, Giovanni Fedele, Jesús Oteo Iglesias, María Teresa Pérez Olmeda, Maria Elena Martinez, Francisco D. Rodríguez-Cabrera1, Susana Padrones Fernández, José Manuel Rumbao Aguirre, José M. Navarro Marí, Begoña Palop Borrás, Ana Belén Pérez Jiménez, Manuel Rodríguez-Iglesias, Ana María Calvo Gascón, María Luz Lou Alcaine, Ignacio Donate Suárez, Oscar Suárez Álvarez, Mercedes Rodríguez Pérez, Margarita Cases Sanchís, Carlos Javier Villafáfila Gomila, Lluis Carbo Saladrigas, Adoración Hurtado Fernández, Antonio Oliver, Elías Castro Feliciano, María Noemí González Quintana, José María Barrasa Fernández, María Araceli Hernández Betancor, Melisa Hernández Febles, Leopoldo Martín Martín, Luis-Mariano López López, Teresa Ugarte Miota, Inés De Benito Población, María Sagrario Celada Pérez, María Natalia Vallés Fernández, Tomás Maté Enríquez, Miguel Villa Arranz, Marta Domínguez-Gil González, Isabel Fernández-Natal, Gregoria Megías Lobón, Juan Luis Muñoz Bellido, Pilar Ciruela, Ariadna Mas i Casals, Maria Doladé Botías, M. Angeles Marcos Maeso, Dúnia Pérez del Campo, Antonio Félix de Castro, Ramón Limón Ramírez, Maria Francisca Elías Retamosa, Manuela Rubio González, María Sinda Blanco Lobeiras, Alberto Fuentes Losada, Antonio Aguilera, Germán Bou, Yolanda Caro, Noemí Marauri, Luis Miguel Soria Blanco, Isabel González, Montserrat Hernández Pascual, Roberto Alonso Fernández, Natalia Cabrera Castro, Aurora Tomás Lizcano, Cristóbal Ramírez Almagro, M. Hernández, Nieves Ascunce Elizaga, María Ederra Sanz, Carmen Ezpeleta Baquedano, Ana Bustinduy Bascaran, Susana Iglesias Tamayo, Luis Elorduy Otazua, Rebeca Benarroch Benarroch, Jesús Lopera Flores, Antonia Vázquez de la Villa 
TL;DR: In this paper, a nationwide population-based study aims to estimate the seroprevalence of SARS-CoV-2 infection in Spain at national and regional level.

1,435 citations

Journal Article
TL;DR: A new book enPDFd preventing chronic diseases a vital investment to read is offered, offering you a new book to read and helping you to love reading.
Abstract: Let's read! We will often find out this sentence everywhere. When still being a kid, mom used to order us to always read, so did the teacher. Some books are fully read in a week and we need the obligation to support reading. What about now? Do you still love reading? Is reading only for you who have obligation? Absolutely not! We here offer you a new book enPDFd preventing chronic diseases a vital investment to read.

1,432 citations

Journal ArticleDOI
TL;DR: It is suggested that most people who become infected with SARS-CoV-2 will not remain asymptomatic throughout the course of the infection, and combination prevention measures will continue to be needed.
Abstract: BACKGROUND There is disagreement about the level of asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We conducted a living systematic review and meta-analysis to address three questions: (1) Amongst people who become infected with SARS-CoV-2, what proportion does not experience symptoms at all during their infection? (2) Amongst people with SARS-CoV-2 infection who are asymptomatic when diagnosed, what proportion will develop symptoms later? (3) What proportion of SARS-CoV-2 transmission is accounted for by people who are either asymptomatic throughout infection or presymptomatic? METHODS AND FINDINGS We searched PubMed, Embase, bioRxiv, and medRxiv using a database of SARS-CoV-2 literature that is updated daily, on 25 March 2020, 20 April 2020, and 10 June 2020. Studies of people with SARS-CoV-2 diagnosed by reverse transcriptase PCR (RT-PCR) that documented follow-up and symptom status at the beginning and end of follow-up or modelling studies were included. One reviewer extracted data and a second verified the extraction, with disagreement resolved by discussion or a third reviewer. Risk of bias in empirical studies was assessed with an adapted checklist for case series, and the relevance and credibility of modelling studies were assessed using a published checklist. We included a total of 94 studies. The overall estimate of the proportion of people who become infected with SARS-CoV-2 and remain asymptomatic throughout infection was 20% (95% confidence interval [CI] 17-25) with a prediction interval of 3%-67% in 79 studies that addressed this review question. There was some evidence that biases in the selection of participants influence the estimate. In seven studies of defined populations screened for SARS-CoV-2 and then followed, 31% (95% CI 26%-37%, prediction interval 24%-38%) remained asymptomatic. The proportion of people that is presymptomatic could not be summarised, owing to heterogeneity. The secondary attack rate was lower in contacts of people with asymptomatic infection than those with symptomatic infection (relative risk 0.35, 95% CI 0.10-1.27). Modelling studies fit to data found a higher proportion of all SARS-CoV-2 infections resulting from transmission from presymptomatic individuals than from asymptomatic individuals. Limitations of the review include that most included studies were not designed to estimate the proportion of asymptomatic SARS-CoV-2 infections and were at risk of selection biases; we did not consider the possible impact of false negative RT-PCR results, which would underestimate the proportion of asymptomatic infections; and the database does not include all sources. CONCLUSIONS The findings of this living systematic review suggest that most people who become infected with SARS-CoV-2 will not remain asymptomatic throughout the course of the infection. The contribution of presymptomatic and asymptomatic infections to overall SARS-CoV-2 transmission means that combination prevention measures, with enhanced hand hygiene, masks, testing tracing, and isolation strategies and social distancing, will continue to be needed.

822 citations