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1.
Croat Med J ; 63(5): 490-494, 2022 Oct 31.
Artículo en Inglés | MEDLINE | ID: covidwho-2092263

RESUMEN

Acquired antibodies against factor II (prothrombin) are rare and most commonly associated with severe liver disease or vitamin K antagonist treatment. In very rare cases, these antibodies and associated hypoprothrombinemia are found in patients with lupus anticoagulant (LAC), an antiphospholipid antibody that inhibits phospholipid-dependent coagulation tests. This uncommon entity, called lupus anticoagulant-hypoprothrombinemia syndrome (LAHPS), may cause both severe, life-threatening bleeding and a predisposition to thrombosis. Coronavirus disease 2019 (COVID-19) is associated with a variety of coagulation abnormalities and an increased risk of thrombosis. Bleeding may occur, but it is less common than thromboembolism and has mostly been described in association with the severity of the disease and anticoagulation treatment in hospitalized patients, rarely in the post-acute phase of the disease. We report on a case of an 80-year-old man who developed LAHPS with prothrombin antibodies and severe bleeding after COVID-19.


Asunto(s)
Síndrome Antifosfolípido , COVID-19 , Hipoprotrombinemias , Masculino , Humanos , Anciano de 80 o más Años , Hipoprotrombinemias/complicaciones , Inhibidor de Coagulación del Lupus , COVID-19/complicaciones , Protrombina , Susceptibilidad a Enfermedades/complicaciones , Síndrome Antifosfolípido/complicaciones , Hemorragia/etiología
2.
Elife ; 112022 08 09.
Artículo en Inglés | MEDLINE | ID: covidwho-2067161

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOCs) have been key drivers of new coronavirus disease 2019 (COVID-19) pandemic waves. To better understand variant epidemiologic characteristics, here we apply a model-inference system to reconstruct SARS-CoV-2 transmission dynamics in South Africa, a country that has experienced three VOC pandemic waves (i.e. Beta, Delta, and Omicron BA.1) by February 2022. We estimate key epidemiologic quantities in each of the nine South African provinces during March 2020 to February 2022, while accounting for changing detection rates, infection seasonality, nonpharmaceutical interventions, and vaccination. Model validation shows that estimated underlying infection rates and key parameters (e.g. infection-detection rate and infection-fatality risk) are in line with independent epidemiological data and investigations. In addition, retrospective predictions capture pandemic trajectories beyond the model training period. These detailed, validated model-inference estimates thus enable quantification of both the immune erosion potential and transmissibility of three major SARS-CoV-2 VOCs, that is, Beta, Delta, and Omicron BA.1. These findings help elucidate changing COVID-19 dynamics and inform future public health planning.


Asunto(s)
COVID-19 , Pandemias , COVID-19/epidemiología , Susceptibilidad a Enfermedades , Humanos , Estudios Retrospectivos , SARS-CoV-2 , Sudáfrica/epidemiología , Estados Unidos
3.
Emerg Infect Dis ; 28(11): 2171-2180, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: covidwho-2054897

RESUMEN

We examined racial/ethnic disparities for COVID-19 seroconversion and hospitalization within a prospective cohort (n = 6,740) in the United States enrolled in March 2020 and followed-up through October 2021. Potential SARS-CoV-2 exposure, susceptibility to COVID-19 complications, and access to healthcare varied by race/ethnicity. Hispanic and Black non-Hispanic participants had more exposure risk and difficulty with healthcare access than white participants. Participants with more exposure had greater odds of seroconversion. Participants with more susceptibility and more barriers to healthcare had greater odds of hospitalization. Race/ethnicity positively modified the association between susceptibility and hospitalization. Findings might help to explain the disproportionate burden of SARS-CoV-2 infections and complications among Hispanic/Latino/a and Black non-Hispanic persons. Primary and secondary prevention efforts should address disparities in exposure, vaccination, and treatment for COVID-19.


Asunto(s)
COVID-19 , Adulto , Estados Unidos/epidemiología , Humanos , COVID-19/epidemiología , Etnicidad , SARS-CoV-2 , Pandemias , Susceptibilidad a Enfermedades , Estudios Prospectivos , Blancos
4.
Sci Rep ; 12(1): 16105, 2022 Sep 27.
Artículo en Inglés | MEDLINE | ID: covidwho-2050524

RESUMEN

In this paper, we propose a mathematical model to describe the influence of the SARS-CoV-2 virus with correlated sources of randomness and with vaccination. The total human population is divided into three groups susceptible, infected, and recovered. Each population group of the model is assumed to be subject to various types of randomness. We develop the correlated stochastic model by considering correlated Brownian motions for the population groups. As the environmental reservoir plays a weighty role in the transmission of the SARS-CoV-2 virus, our model encompasses a fourth stochastic differential equation representing the reservoir. Moreover, the vaccination of susceptible is also considered. Once the correlated stochastic model, the existence and uniqueness of a positive solution are discussed to show the problem's feasibility. The SARS-CoV-2 extinction, as well as persistency, are also examined, and sufficient conditions resulted from our investigation. The theoretical results are supported through numerical/graphical findings.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiología , COVID-19/prevención & control , Simulación por Computador , Susceptibilidad a Enfermedades/epidemiología , Humanos , Procesos Estocásticos , Vacunación
5.
J Math Biol ; 85(4): 36, 2022 Sep 20.
Artículo en Inglés | MEDLINE | ID: covidwho-2048225

RESUMEN

The Susceptible-Infectious-Recovered (SIR) equations and their extensions comprise a commonly utilized set of models for understanding and predicting the course of an epidemic. In practice, it is of substantial interest to estimate the model parameters based on noisy observations early in the outbreak, well before the epidemic reaches its peak. This allows prediction of the subsequent course of the epidemic and design of appropriate interventions. However, accurately inferring SIR model parameters in such scenarios is problematic. This article provides novel, theoretical insight on this issue of practical identifiability of the SIR model. Our theory provides new understanding of the inferential limits of routinely used epidemic models and provides a valuable addition to current simulate-and-check methods. We illustrate some practical implications through application to a real-world epidemic data set.


Asunto(s)
Enfermedades Transmisibles , Epidemias , Enfermedades Transmisibles/epidemiología , Brotes de Enfermedades , Susceptibilidad a Enfermedades/epidemiología , Modelos Epidemiológicos , Humanos
6.
Sci Rep ; 12(1): 15688, 2022 09 20.
Artículo en Inglés | MEDLINE | ID: covidwho-2036895

RESUMEN

An Adaptive Susceptible-Infected-Removed-Vaccinated (A-SIRV) epidemic model with time-dependent transmission and removal rates is constructed for investigating the dynamics of an epidemic disease such as the COVID-19 pandemic. Real data of COVID-19 spread is used for the simultaneous identification of the unknown time-dependent rates and functions participating in the A-SIRV system. The inverse problem is formulated and solved numerically using the Method of Variational Imbedding, which reduces the inverse problem to a problem for minimizing a properly constructed functional for obtaining the sought values. To illustrate and validate the proposed solution approach, the present study used available public data for several countries with diverse population and vaccination dynamics-the World, Israel, The United States of America, and Japan.


Asunto(s)
COVID-19 , COVID-19/epidemiología , COVID-19/prevención & control , Susceptibilidad a Enfermedades/epidemiología , Modelos Epidemiológicos , Humanos , Modelos Biológicos , Pandemias/prevención & control , Vacunación/métodos
7.
Endocrinology ; 163(11)2022 10 11.
Artículo en Inglés | MEDLINE | ID: covidwho-2021399

RESUMEN

Several observational studies have confirmed the relationship between thyroid hormones and coronavirus disease 2019 (COVID-19), but this correlation remains controversial. We performed a two-sample Mendelian randomization (MR) analysis based on the largest publicly available summary datasets. Summary statistics with 49 269 individuals for free thyroxine (FT4) and 54 288 for thyroid stimulating hormone (TSH) were used as exposure instruments. Genome-wide association studies of susceptibility (cases = 38 984; controls = 1 644 784), hospitalization (cases: 9986 = controls = 1 877 672), and very severe disease (cases = 5101; controls = 1 383 241) of COVID-19 were used as the outcome. We used the inverse-variance weighted (IVW) method as the primary analysis, and utilized MR-Egger regression, weighted median, and robust adjusted profile score (RAPS) for sensitivity analysis. Genetic predisposition to higher serum levels of FT4 within the normal range was negatively associated with the risk of COVID-19 hospitalization (odds ratio [OR] = 0.818; 95% CI, 0.718-0.932; P = 2.6 × 10-3) and very severe disease (OR = 0.758; 95% CI, 0.626-0.923; P = 5.8 × 10-3), but not susceptibility. There is no evidence that genetically predicted circulating TSH levels are associated with COVID-19 susceptibility and severity risk. Neither apparent pleiotropy nor heterogeneity were detected in the sensitivity analysis. In summary, we found that higher FT4 levels may reduce the risk of COVID-19 severity, suggesting that thyroid function testing may be required for patients with COVID-19.


Asunto(s)
COVID-19 , Glándula Tiroides , COVID-19/diagnóstico , Susceptibilidad a Enfermedades , Estudio de Asociación del Genoma Completo , Humanos , Análisis de la Aleatorización Mendeliana/métodos , Glándula Tiroides/fisiopatología , Tirotropina , Tiroxina
8.
PLoS One ; 17(9): e0273945, 2022.
Artículo en Inglés | MEDLINE | ID: covidwho-2009714

RESUMEN

The COVID-19 pandemic has had medical, economic and behavioral implications on a global scale, with research emerging to indicate that it negatively impacted the population's mental health as well. The current study utilizes longitudinal data to assess whether the pandemic led to an increase in depression and anxiety across participants or whether a diathesis-stress model would be more appropriate. An international group of 218 participants completed measures of depression, anxiety, rumination and distress intolerance at two baselines six months apart as well as during the onset of the COVID-19 pandemic exactly 12 months later. Contrary to expectations, depression, rumination, and distress intolerance were at equivalent levels during the pandemic as they were at baseline. Anxiety was reduced by a trivial degree (d = .10). Furthermore, a comparison of quantitative explanatory models indicated that symptom severity and pandemic-related environmental stressors predicted pandemic-related distress. Pandemic-related distress did not predict symptom severity. These findings underscore the necessity of longitudinal designs and diathesis-stress models in the study of mental health during the COVID-19 pandemic. They also emphasize that individuals with higher rates of baseline psychopathology are as particularly at risk for higher levels of distress in response to disaster-related stressors.


Asunto(s)
COVID-19 , Pandemias , Ansiedad/epidemiología , Ansiedad/psicología , COVID-19/epidemiología , Depresión/epidemiología , Depresión/psicología , Susceptibilidad a Enfermedades , Humanos , Estudios Longitudinales
9.
Proc Natl Acad Sci U S A ; 119(35): e2122851119, 2022 08 30.
Artículo en Inglés | MEDLINE | ID: covidwho-2001002

RESUMEN

Disease transmission prediction across wildlife is crucial for risk assessment of emerging infectious diseases. Susceptibility of host species to pathogens is influenced by the geographic, environmental, and phylogenetic context of the specific system under study. We used machine learning to analyze how such variables influence pathogen incidence for multihost pathogen assemblages, including one of direct transmission (coronaviruses and bats) and two vector-borne systems (West Nile Virus [WNV] and birds, and malaria and birds). Here we show that this methodology is able to provide reliable global spatial susceptibility predictions for the studied host-pathogen systems, even when using a small amount of incidence information (i.e., [Formula: see text] of information in a database). We found that avian malaria was mostly affected by environmental factors and by an interaction between phylogeny and geography, and WNV susceptibility was mostly influenced by phylogeny and by the interaction between geographic and environmental distances, whereas coronavirus susceptibility was mostly affected by geography. This approach will help to direct surveillance and field efforts providing cost-effective decisions on where to invest limited resources.


Asunto(s)
Animales Salvajes , Enfermedades Transmisibles Emergentes , Susceptibilidad a Enfermedades , Animales , Animales Salvajes/parasitología , Animales Salvajes/virología , Enfermedades de las Aves/epidemiología , Enfermedades de las Aves/transmisión , Quirópteros/virología , Enfermedades Transmisibles Emergentes/epidemiología , Enfermedades Transmisibles Emergentes/transmisión , Enfermedades Transmisibles Emergentes/veterinaria , Coronavirus , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/transmisión , Infecciones por Coronavirus/veterinaria , Bases de Datos Factuales , Ambiente , Monitoreo Epidemiológico , Geografía , Interacciones Huésped-Patógeno , Incidencia , Aprendizaje Automático , Malaria/epidemiología , Malaria/transmisión , Malaria/veterinaria , Filogenia , Medición de Riesgo , Fiebre del Nilo Occidental/epidemiología , Fiebre del Nilo Occidental/transmisión , Fiebre del Nilo Occidental/veterinaria , Virus del Nilo Occidental
10.
Sci Rep ; 12(1): 9706, 2022 06 11.
Artículo en Inglés | MEDLINE | ID: covidwho-1984420

RESUMEN

Recurrent updates in non-pharmaceutical interventions (NPIs) aim to control successive waves of the coronavirus disease 2019 (COVID-19) but are often met with low adherence by the public. This study evaluated the effectiveness of gathering restrictions and quarantine policies based on a modified Susceptible-Exposed-Infectious-Hospitalized-Recovered (SEIHR) model by incorporating cross-boundary travellers with or without quarantine to study the transmission dynamics of COVID-19 with data spanning a nine-month period during 2020 in Hong Kong. The asymptotic stability of equilibria reveals that the model exhibits the phenomenon of backward bifurcation, which in this study is a co-existence between a stable disease-free equilibrium (DFE) and an endemic equilibrium (EE). Even if the basic reproduction number ([Formula: see text]) is less than unity, this disease cannot be eliminated. The effect of each parameter on the overall dynamics was assessed using Partial Rank Correlation Coefficients (PRCCs). Transmission rates (i.e., [Formula: see text] and [Formula: see text]), effective contact ratio [Formula: see text] between symptomatic individuals and quarantined people, and transfer rate [Formula: see text] related to infection during quarantine were identified to be the most sensitive parameters. The effective contact ratios between the infectors and susceptible individuals in late July were found to be over twice as high as that in March of 2020, reflecting pandemic fatigue and the potential existence of infection during quarantine.


Asunto(s)
COVID-19 , Pandemias , Número Básico de Reproducción , COVID-19/epidemiología , Susceptibilidad a Enfermedades , Fatiga/epidemiología , Humanos , Pandemias/prevención & control , Cuarentena
11.
Sci Rep ; 12(1): 9641, 2022 06 10.
Artículo en Inglés | MEDLINE | ID: covidwho-1984413

RESUMEN

After more than 6 million deaths worldwide, the ongoing vaccination to conquer the COVID-19 disease is now competing with the emergence of increasingly contagious mutations, repeatedly supplanting earlier strains. Following the near-absence of historical examples of the long-time evolution of infectious diseases under similar circumstances, models are crucial to exemplify possible scenarios. Accordingly, in the present work we systematically generalize the popular susceptible-infected-recovered model to account for mutations leading to repeatedly occurring new strains, which we coarse grain based on tools from statistical mechanics to derive a model predicting the most likely outcomes. The model predicts that mutations can induce a super-exponential growth of infection numbers at early times, which self-amplify to giant infection waves which are caused by a positive feedback loop between infection numbers and mutations and lead to a simultaneous infection of the majority of the population. At later stages-if vaccination progresses too slowly-mutations can interrupt an ongoing decrease of infection numbers and can cause infection revivals which occur as single waves or even as whole wave trains featuring alternative periods of decreasing and increasing infection numbers. This panorama of possible mutation-induced scenarios should be tested in more detailed models to explore their concrete significance for specific infectious diseases. Further, our results might be useful for discussions regarding the importance of a release of vaccine-patents to reduce the risk of mutation-induced infection revivals but also to coordinate the release of measures following a downwards trend of infection numbers.


Asunto(s)
COVID-19 , Enfermedades Transmisibles , Susceptibilidad a Enfermedades , Humanos , Mutación , Vacunación
12.
Trends Immunol ; 43(8): 640-656, 2022 08.
Artículo en Inglés | MEDLINE | ID: covidwho-1972143

RESUMEN

Tuberculosis (TB), the world's deadliest bacterial infection, afflicts more human males than females, with a male/female (M/F) ratio of 1.7. Sex disparities in TB prevalence, pathophysiology, and clinical manifestations are widely reported, but the underlying biological mechanisms remain largely undefined. This review assesses epidemiological data on sex disparity in TB, as well as possible underlying hormonal and genetic mechanisms that might differentially modulate innate and adaptive immune responses in males and females, leading to sex differences in disease susceptibility. We consider whether this sex disparity can be extended to the efficacy of vaccines and discuss novel animal models which may offer mechanistic insights. A better understanding of the biological factors underpinning sex-related immune responses in TB may enable sex-specific personalized therapies for TB.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Animales , Susceptibilidad a Enfermedades , Femenino , Humanos , Inmunidad , Masculino , Tuberculosis/genética
13.
PLoS One ; 17(7): e0272019, 2022.
Artículo en Inglés | MEDLINE | ID: covidwho-1963043

RESUMEN

Coronavirus disease (COVID-19), caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), is currently spreading globally. To overcome the COVID-19 pandemic, preclinical evaluations of vaccines and therapeutics using K18-hACE2 and CAG-hACE2 transgenic mice are ongoing. However, a comparative study on SARS-CoV-2 infection between K18-hACE2 and CAG-hACE2 mice has not been published. In this study, we compared the susceptibility and resistance to SARS-CoV-2 infection between two strains of transgenic mice, which were generated in FVB background mice. K18-hACE2 mice exhibited severe weight loss with definitive lethality, but CAG-hACE2 mice survived; and differences were observed in the lung, spleen, cerebrum, cerebellum, and small intestine. A higher viral titer was detected in the lungs, cerebrums, and cerebellums of K18-hACE2 mice than in the lungs of CAG-hACE2 mice. Severe pneumonia was observed in histopathological findings in K18-hACE2, and mild pneumonia was observed in CAG-hACE2. Atrophy of the splenic white pulp and reduction of spleen weight was observed, and hyperplasia of goblet cells with villi atrophy of the small intestine was observed in K18-hACE2 mice compared to CAG-hACE2 mice. These results indicate that K18-hACE2 mice are relatively susceptible to SARS-CoV-2 and that CAG-hACE2 mice are resistant to SARS-CoV-2. Based on these lineage-specific sensitivities, we suggest that K18-hACE2 mouse is suitable for highly susceptible model of SARS-CoV-2, and CAG-hACE2 mouse is suitable for mild susceptible model of SARS-CoV-2 infection.


Asunto(s)
COVID-19 , Neumonía , Enzima Convertidora de Angiotensina 2/genética , Animales , Atrofia/patología , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades/patología , Humanos , Pulmón/patología , Ratones , Ratones Endogámicos , Ratones Transgénicos , Pandemias , Peptidil-Dipeptidasa A , Neumonía/patología , SARS-CoV-2
14.
Infect Dis Poverty ; 11(1): 72, 2022 Jun 21.
Artículo en Inglés | MEDLINE | ID: covidwho-1962900

RESUMEN

BACKGROUND: The coronavirus disease 2019 (COVID-19) epidemic, considered as the worst global public health event in nearly a century, has severely affected more than 200 countries and regions around the world. To effectively prevent and control the epidemic, researchers have widely employed dynamic models to predict and simulate the epidemic's development, understand the spread rule, evaluate the effects of intervention measures, inform vaccination strategies, and assist in the formulation of prevention and control measures. In this review, we aimed to sort out the compartmental structures used in COVID-19 dynamic models and provide reference for the dynamic modeling for COVID-19 and other infectious diseases in the future. MAIN TEXT: A scoping review on the compartmental structures used in modeling COVID-19 was conducted. In this scoping review, 241 research articles published before May 14, 2021 were analyzed to better understand the model types and compartmental structures used in modeling COVID-19. Three types of dynamics models were analyzed: compartment models expanded based on susceptible-exposed-infected-recovered (SEIR) model, meta-population models, and agent-based models. The expanded compartments based on SEIR model are mainly according to the COVID-19 transmission characteristics, public health interventions, and age structure. The meta-population models and the agent-based models, as a trade-off for more complex model structures, basic susceptible-exposed-infected-recovered or simply expanded compartmental structures were generally adopted. CONCLUSION: There has been a great deal of models to understand the spread of COVID-19, and to help prevention and control strategies. Researchers build compartments according to actual situation, research objectives and complexity of models used. As the COVID-19 epidemic remains uncertain and poses a major challenge to humans, researchers still need dynamic models as the main tool to predict dynamics, evaluate intervention effects, and provide scientific evidence for the development of prevention and control strategies. The compartmental structures reviewed in this study provide guidance for future modeling for COVID-19, and also offer recommendations for the dynamic modeling of other infectious diseases.


Asunto(s)
COVID-19 , Epidemias , COVID-19/epidemiología , Susceptibilidad a Enfermedades , Predicción , Humanos , Salud Pública , SARS-CoV-2
17.
Sci Rep ; 12(1): 11855, 2022 07 25.
Artículo en Inglés | MEDLINE | ID: covidwho-1960495

RESUMEN

The coronavirus disease 2019 (COVID-19), caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), remains to spread worldwide. COVID-19 is characterized by the striking high mortality in elderly; however, its mechanistic insights remain unclear. Systemic thrombosis has been highlighted in the pathogenesis of COVID-19, and lung microangiopathy in association with endothelial cells (ECs) injury has been reported by post-mortem analysis of the lungs. Here, we experimentally investigated the SARS-CoV-2 infection in cultured human ECs, and performed a comparative analysis for post-infection molecular events using early passage and replicative senescent ECs. We found that; (1) SARS-CoV-2 infects ECs but does not replicate and disappears in 72 hours without causing severe cell damage, (2) Senescent ECs are highly susceptible to SARS-CoV-2 infection, (3) SARS-CoV-2 infection alters various genes expression, which could cause EC dysfunctions, (4) More genes expression is affected in senescent ECs by SARS-CoV-2 infection than in early passage ECs, which might causes further exacerbated dysfunction in senescent ECs. These data suggest that sustained EC dysfunctions due to SARS-CoV-2 infection may contribute to the microangiopathy in the lungs, leading to deteriorated inflammation and thrombosis in COVID-19. Our data also suggest a possible causative role of EC senescence in the aggravated disease in elder COVID-19 patients.


Asunto(s)
COVID-19 , Trombosis , Anciano , Susceptibilidad a Enfermedades/metabolismo , Células Endoteliales/metabolismo , Humanos , SARS-CoV-2 , Trombosis/patología
18.
J Prev Med Hyg ; 63(1): E12-E18, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: covidwho-1955101

RESUMEN

Background: The COVID-19 pandemic has become a grave threat to public health. Along with vaccination, preventive behaviors are still an important part in controlling in controlling the COVID-19 pandemic. The present study aimed to investigate health beliefs and sample characteristics associated with COVID-19 preventive health behaviors among an Iranian sample. Preventive behaviors are still an important part in controlling in controlling the COVID-19 pandemic. Methods: This is a cross-sectional study, using a multi-stage randomized sampling method. Participants (N = 250 males and 236 females) were recruited from health centers in Saveh, Iran. Self-administered questionnaires included sociodemographic information, health behaviors, and constructs associated with the Health Beliefs Model (HBM). Data were analyzed using independent t-tests, analysis of variance, and multiple regression with significance level set at α ≤ 0.05. Results: Perceived disease susceptibility (ß = 0.44, P< 0.001), self-efficacy to enact preventative behaviors (ß = 0.24, P < 0.01), education (ß = 0.20, P < 0.001), non-smoking status (ß = 0.14, P < 0.01), marital status (ß = 0.10, P < 0.03), and perceived barriers to disease preventative behaviors (ß = -0.10, P < 0.04) were important predictors of prevention practices for COVID-19, and accounted for 61.4% (adjusted R2) of the variance associated with preventive behavior for COVID-19. Conclusion: As there is accepted therapy for COVID-19, it is especially important to control COVID-19 through behavior change. Results indicate that two behavioral constructs that have the most impact on prevention are perceived disease susceptibility and self-efficacy. Therefore, public health initiatives are needed to enhance perceived susceptibility to the disease and improve self-efficacy to perform preventative behaviors in spite of perceived barriers.


Asunto(s)
COVID-19 , COVID-19/prevención & control , Estudios Transversales , Susceptibilidad a Enfermedades , Femenino , Humanos , Irán/epidemiología , Masculino , Pandemias/prevención & control , Encuestas y Cuestionarios
19.
Int J Infect Dis ; 122: 300-306, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: covidwho-1945191

RESUMEN

OBJECTIVES: COVID-19 vaccination in Japan started on February 17, 2021. Because the timing of vaccination and the risk of severe COVID-19 greatly varied with age, the present study aimed to monitor the age-specific fractions of the population who were immune to SARS-CoV-2 infection after vaccination. METHODS: Natural infection remained extremely rare, accounting for less than 5% of the population by the end of 2021; thus, we ignored natural infection-induced immunity and focused on vaccine-induced immunity. We estimated the fraction of the population immune to infection by age group using vaccination registry data from February 17, 2021, to October 17, 2021. We accounted for two important sources of delay: (i) reporting delay and (ii) time from vaccination until immune protection develops. RESULTS: At the end of the observation period, the proportion of individuals still susceptible to SARS-CoV-2 infection substantially varied by age and was estimated to be ≥90% among people aged 0-14 years, in contrast to approximately 20% among the population aged ≥65 years. We also estimated the effective reproduction number over time using a next-generation matrix while accounting for differences in the proportion immune to infection by age. CONCLUSION: The COVID-19 immune landscape greatly varied by age, and a substantial proportion of young adults remained susceptible. Vaccination contributed to a marked decrease in the reproduction number.


Asunto(s)
COVID-19 , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19 , Susceptibilidad a Enfermedades , Humanos , Japón/epidemiología , SARS-CoV-2 , Vacunación , Adulto Joven
20.
Medicina (Kaunas) ; 58(7)2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: covidwho-1938900

RESUMEN

Background and Objectives: Starting in early December 2019, the novel Coronavirus Disease (COVID-19) from infection with COVID-19 has caused a global pandemic. Many aspects of its pathogenesis and related clinical consequences are still unclear. Early diagnosis and dynamic monitoring of prognostic factors are essential to improve the ability to manage COVID-19 infection. This study aimed to provide an account of the role played by vitamins C and D on the onset, progression and severity of COVID-19. Clinical features and infection-related risk factors are also briefly discussed. Material and Methods: In March 2022, the main online databases were accessed. All the articles that investigate the possible role of vitamins C and D on COVID-19 susceptibility, severity and progression were considered. Results: The current evidence on vitamin C and D supplementation in patients with COVID-19 infection is inconsistent and controversial. In some studies, vitamins were used as coadjuvant of a formal experimental therapy, while in others as main treatment. Ethnicity and hospital setting (inpatient/outpatient) were also variable. Moreover, there was no consensus between studies in administration protocol: high heterogeneity in dosage, administration, and duration of the treatment were evident. Finally, some studies administered vitamins pre- and/or during COVID infection, in patients with different risk factors and infection severity. Conclusions: While waiting to develop a targeted, safe and effective therapy, it is important to investigate individual predisposition and proper disease management. Concluding, available data on the use of nutraceuticals in COVID-19 are inconsistent. However, there is a lack of evidence-based guidelines which recommend vitamin C and D supplementation in patients with COVID-19, and results from high quality randomised controlled trials (RCTs) are inconsistent. Current investigations so far are mostly observational, and include a relatively small sample size which can lead to biased results. Large-scale multicentre studies are therefore needed.


Asunto(s)
Ácido Ascórbico , COVID-19 , Vitamina D , Vitaminas , Ácido Ascórbico/uso terapéutico , COVID-19/terapia , Susceptibilidad a Enfermedades , Humanos , Pandemias , SARS-CoV-2 , Vitamina D/uso terapéutico , Vitaminas/uso terapéutico
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