Browsing by Subject "Asymptomatic Infections"

Now showing 1 - 6 of 6
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    Age-related model for estimating the symptomatic and asymptomatic transmissibility of COVID-19 patients.
    (Biometrics, 2023-09) Tan, Jianbin; Shen, Ye; Ge, Yang; Martinez, Leonardo; Huang, Hui
    Estimation of age-dependent transmissibility of COVID-19 patients is critical for effective policymaking. Although the transmissibility of symptomatic cases has been extensively studied, asymptomatic infection is understudied due to limited data. Using a dataset with reliably distinguished symptomatic and asymptomatic statuses of COVID-19 cases, we propose an ordinary differential equation model that considers age-dependent transmissibility in transmission dynamics. Under a Bayesian framework, multi-source information is synthesized in our model for identifying transmissibility. A shrinkage prior among age groups is also adopted to improve the estimation behavior of transmissibility from age-structured data. The added values of accounting for age-dependent transmissibility are further evaluated through simulation studies. In real-data analysis, we compare our approach with two basic models using the deviance information criterion (DIC) and its extension. We find that the proposed model is more flexible for our epidemic data. Our results also suggest that the transmissibility of asymptomatic infections is significantly lower (on average, 76.45% with a credible interval (27.38%, 88.65%)) than that of symptomatic cases. In both symptomatic and asymptomatic patients, the transmissibility mainly increases with age. Patients older than 30 years are more likely to develop symptoms with higher transmissibility. We also find that the transmission burden of asymptomatic cases is lower than that of symptomatic patients.
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    Assessment of an Online Tool to Simulate the Effect of Pooled Testing for SARS-CoV-2 Detection in Asymptomatic and Symptomatic Populations.
    (JAMA network open, 2020-12) Polage, Christopher R; Lee, Mark J; Hubbard, Christopher; Rehder, Catherine; Cardona, Diana; Denny, Thomas; Datto, Michael B
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    Lower likelihood of cardiac procedures after acute coronary syndrome in patients with human immunodeficiency virus/acquired immunodeficiency syndrome.
    (Medicine, 2018-02) Clement, Meredith E; Lin, Li; Navar, Ann Marie; Okeke, Nwora Lance; Naggie, Susanna; Douglas, Pamela S
    Cardiovascular disease (CVD) is an increasing cause of morbidity and mortality in human immunodeficiency virus (HIV)-infected adults; however, this population may be less likely to receive interventions during hospitalization for acute coronary syndrome (ACS). The degree to which this disparity can be attributed to poorly controlled HIV infection is unknown.In this large cohort study, we used the National Inpatient Sample (NIS) to compare rates of cardiac procedures among patients with asymptomatic HIV-infection, symptomatic acquired immunodeficiency syndrome (AIDS), and uninfected adults hospitalized with ACS from 2009 to 2012. Multivariable analysis was used to compare procedure rates by HIV status, with appropriate weighting to account for NIS sampling design including stratification and hospital clustering.The dataset included 1,091,759 ACS hospitalizations, 0.35% of which (n = 3783) were in HIV-infected patients. Patients with symptomatic AIDS, asymptomatic HIV, and uninfected patients differed by sex, race, and income status. Overall rates of cardiac catheterization and revascularization were 53.3% and 37.4%, respectively. In multivariable regression, we found that relative to uninfected patients, those with symptomatic AIDS were less likely to undergo catheterization (odds ratio [OR] 0.48, confidence interval [CI] 0.43-0.55), percutaneous coronary intervention (OR 0.69, CI 0.59-0.79), and coronary artery bypass grafting (0.75, CI 0.61-0.93). No difference was seen for those with asymptomatic HIV relative to uninfected patients (OR 0.93, CI 0.81-1.07; OR 1.06, CI 0.93-1.21; OR 0.88, CI 0.72-1.06, respectively).We found that lower rates of cardiovascular procedures in HIV-infected patients were primarily driven by less frequent procedures in those with AIDS.
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    Temporal dynamics of host molecular responses differentiate symptomatic and asymptomatic influenza a infection.
    (PLoS Genet, 2011-08) Huang, Yongsheng; Zaas, Aimee K; Rao, Arvind; Dobigeon, Nicolas; Woolf, Peter J; Veldman, Timothy; Øien, N Christine; McClain, Micah T; Varkey, Jay B; Nicholson, Bradley; Carin, Lawrence; Kingsmore, Stephen; Kingsmore, Stephen; Woods, Christopher W; Ginsburg, Geoffrey S; Hero, Alfred O
    Exposure to influenza viruses is necessary, but not sufficient, for healthy human hosts to develop symptomatic illness. The host response is an important determinant of disease progression. In order to delineate host molecular responses that differentiate symptomatic and asymptomatic Influenza A infection, we inoculated 17 healthy adults with live influenza (H3N2/Wisconsin) and examined changes in host peripheral blood gene expression at 16 timepoints over 132 hours. Here we present distinct transcriptional dynamics of host responses unique to asymptomatic and symptomatic infections. We show that symptomatic hosts invoke, simultaneously, multiple pattern recognition receptors-mediated antiviral and inflammatory responses that may relate to virus-induced oxidative stress. In contrast, asymptomatic subjects tightly regulate these responses and exhibit elevated expression of genes that function in antioxidant responses and cell-mediated responses. We reveal an ab initio molecular signature that strongly correlates to symptomatic clinical disease and biomarkers whose expression patterns best discriminate early from late phases of infection. Our results establish a temporal pattern of host molecular responses that differentiates symptomatic from asymptomatic infections and reveals an asymptomatic host-unique non-passive response signature, suggesting novel putative molecular targets for both prognostic assessment and ameliorative therapeutic intervention in seasonal and pandemic influenza.
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    Transmission roles of symptomatic and asymptomatic COVID-19 cases: a modelling study.
    (Epidemiology and infection, 2022-09) Tan, Jianbin; Ge, Yang; Martinez, Leonardo; Sun, Jimin; Li, Changwei; Westbrook, Adrianna; Chen, Enfu; Pan, Jinren; Li, Yang; Cheng, Wei; Ling, Feng; Chen, Zhiping; Shen, Ye; Huang, Hui
    Coronavirus disease 2019 (COVID-19) asymptomatic cases are hard to identify, impeding transmissibility estimation. The value of COVID-19 transmissibility is worth further elucidation for key assumptions in further modelling studies. Through a population-based surveillance network, we collected data on 1342 confirmed cases with a 90-days follow-up for all asymptomatic cases. An age-stratified compartmental model containing contact information was built to estimate the transmissibility of symptomatic and asymptomatic COVID-19 cases. The difference in transmissibility of a symptomatic and asymptomatic case depended on age and was most distinct for the middle-age groups. The asymptomatic cases had a 66.7% lower transmissibility rate than symptomatic cases, and 74.1% (95% CI 65.9-80.7) of all asymptomatic cases were missed in detection. The average proportion of asymptomatic cases was 28.2% (95% CI 23.0-34.6). Simulation demonstrated that the burden of asymptomatic transmission increased as the epidemic continued and could potentially dominate total transmission. The transmissibility of asymptomatic COVID-19 cases is high and asymptomatic COVID-19 cases play a significant role in outbreaks.
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    Universal masking is an effective strategy to flatten the severe acute respiratory coronavirus virus 2 (SARS-CoV-2) healthcare worker epidemiologic curve.
    (Infection control and hospital epidemiology, 2020-12) Seidelman, Jessica L; Lewis, Sarah S; Advani, Sonali D; Akinboyo, Ibukunoluwa C; Epling, Carol; Case, Matthew; Said, Kristen; Yancey, William; Stiegel, Matthew; Schwartz, Antony; Stout, Jason; Sexton, Daniel J; Smith, Becky A