Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Heterogeneity in viral shedding among individuals with medically attended influenza A virus infection.

ABSTRACT: Compared with the average transmissibility of human influenza A virus, much less attention has been paid to the potential variability in its transmissibility. We considered viral shedding as a proxy for infectiousness and explored the heterogeneity of infectiousness among patients with medically attended seasonal influenza A virus infection. The analysis revealed that viral shedding is more heterogeneous in children than in adults. The top 20% most infectious children and adults were estimated to be responsible for 89%-96% and 78%-82%, respectively, of the total infectiousness in each age group. Further investigation is required to correlate the substantial variations in viral shedding with heterogeneity in actual transmissibility.

SUBMITTER: Lau LL

PROVIDER: S-EPMC3603536 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Heterogeneity in viral shedding among individuals with medically attended influenza A virus infection.

Lau Lincoln L H LL Ip Dennis K M DK Nishiura Hiroshi H Fang Vicky J VJ Chan Kwok-Hung KH Peiris J S Malik JS Leung Gabriel M GM Cowling Benjamin J BJ

The Journal of infectious diseases 20130204 8

Compared with the average transmissibility of human influenza A virus, much less attention has been paid to the potential variability in its transmissibility. We considered viral shedding as a proxy for infectiousness and explored the heterogeneity of infectiousness among patients with medically attended seasonal influenza A virus infection. The analysis revealed that viral shedding is more heterogeneous in children than in adults. The top 20% most infectious children and adults were estimated t ...[more]

PMID: 23382573

Similar Datasets

Influenza Vaccine Intention After a Medically Attended Acute Respiratory Infection.

Project description:Background. Little is known about vaccine intention behavior among patients recovering from a medically attended acute respiratory infection. Methods. Adults ? 18 years old with an acute respiratory infection in the 2014-2015, 2015-2016, and 2016-2017 influenza seasons were tested for influenza and completed surveys. Across seasons, unvaccinated participants were grouped into those who intended to receive the influenza vaccine in the following season (vaccine intention) and those who did not (no vaccine intention). In 2016-2017, participants were asked the reasons for their vaccination behavior. Results. Of the 837 unvaccinated participants, 308 (37%) intended to be vaccinated the next season. The groups did not differ in demographic or overall health factors. In logistic regression, non-Whites, those reporting wheezing or nasal congestion, and those receiving an antiviral prescription were more likely to be in the vaccine intention group. That group was significantly more likely to cite perceived behavioral control reasons for not being vaccinated (forgot), while the no vaccine intention group was significantly (p < .001) more likely to report knowledge/attitudinal reasons (side effects). Conclusion. Because influenza vaccine is given annually, adults must make a conscious decision to receive the vaccine each year. Understanding the factors related to vaccination behavior and intent can help shape interventions to improve influenza vaccination rates. A medical visit at the time of an acute respiratory illness, especially one in which the provider suspects influenza, as evidenced by an antiviral prescription, is an ideal opportunity to recommend influenza vaccine in the next season, to prevent a similar experience.

| S-EPMC6389426 | biostudies-literature

Burden of medically attended influenza in Norway 2008-2017.

Project description:BackgroundThe burden of influenza in Norway remains uncertain, and data on seasonal variations and differences by age groups are needed.ObjectiveTo describe number of patients diagnosed with influenza in Norway each season and the number treated in primary or specialist health care by age. Further, to compare the burden of seasonal influenza with the 2009-2010 pandemic outbreak.MethodsWe used Norwegian national health registries and identified all patients diagnosed with influenza from 2008 to 2017. We calculated seasonal rates, compared hospitalized patients with patients in primary care and compared seasonal influenza with the 2009-2010 pandemic outbreak.ResultsEach season, on average 1.7% of the population were diagnosed with influenza in primary care, the average rate of hospitalization was 48 per 100 000 population while the average number of hospitalized patients each season was nearly 2500. The number of hospitalized influenza patients ranged from 579 in 2008-2009 to 4973 in 2016-2017. Rates in primary care were highest among young adults while hospitalization rates were highest in patients 80 years and older and in children below 5 years. The majority of in-hospital deaths were in patients 70 years and older. Fewer patients were hospitalized during the 2009-2010 pandemic than in seasonal outbreaks, but during the pandemic, more people in the younger age groups were hospitalized and fatal cases were younger.ConclusionInfluenza causes a substantial burden in primary care and hospitals. In non-pandemic seasons, people above 80 years have the highest risk of influenza hospitalization and death.

| S-EPMC6468058 | biostudies-literature

Suptavumab for the Prevention of Medically Attended Respiratory Syncytial Virus Infection in Preterm Infants.

Project description:BackgroundRespiratory syncytial virus (RSV) is a major cause of childhood medically attended respiratory infection (MARI).MethodsWe conducted a randomized, double-blind, placebo-controlled phase 3 trial in 1154 preterm infants of 1 or 2 doses of suptavumab, a human monoclonal antibody that can bind and block a conserved epitope on RSV A and B subtypes, for the prevention of RSV MARI. The primary endpoint was proportion of subjects with RSV-confirmed hospitalizations or outpatient lower respiratory tract infection (LRTI).ResultsThere were no significant differences between primary endpoint rates (8.1%, placebo; 7.7%, 1-dose; 9.3%, 2-dose). Suptavumab prevented RSV A infections (relative risks, .38; 95% confidence interval [CI], .14-1.05 in the 1-dose group and .39 [95% CI, .14-1.07] in the 2-dose group; nominal significance of combined suptavumab group vs placebo; P = .0499), while increasing the rate of RSV B infections (relative risk 1.36 [95% CI, .73-2.56] in the 1-dose group and 1.69 [95% CI, .92-3.08] in the 2-dose group; nominal significance of combined suptavumab group vs placebo; P = .12). Sequenced RSV isolates demonstrated no suptavumab epitope changes in RSV A isolates, while all RSV B isolates had 2-amino acid substitution in the suptavumab epitope that led to loss of neutralization activity. Treatment emergent adverse events were balanced across treatment groups.ConclusionsSuptavumab did not reduce overall RSV hospitalizations or outpatient LRTI because of a newly circulating mutant strain of RSV B. Genetic variation in circulating RSV strains will continue to challenge prevention efforts.Clinical trials registrationNCT02325791.

| S-EPMC8653633 | biostudies-literature

Burden of medically attended influenza infection and cases averted by vaccination - United States, 2013/14 through 2015/16 influenza seasons.

Project description:BACKGROUND:In addition to preventing hospitalizations and deaths due to influenza, influenza vaccination programs can reduce the burden of outpatient visits for influenza. We estimated the incidence of medically-attended influenza at three geographically diverse sites in the United States, and the cases averted by vaccination, for the 2013/14 through 2015/16 influenza seasons. METHODS:We defined surveillance populations at three sites from the United States Influenza Vaccine Effectiveness Network. Among these populations, we identified outpatient visits laboratory-confirmed influenza via active surveillance, and identified all outpatient visits for acute respiratory illness from healthcare databases. We extrapolated the total number of outpatient visits for influenza from the proportion of surveillance visits with a positive influenza test. We combined estimates of incidence, vaccine coverage, and vaccine effectiveness to estimate outpatient visits averted by vaccination. RESULTS:Across the three sites and seasons, incidence of medically attended influenza ranged from 14 to 54 per 1000 population. Incidence was highest in children aged 6?months to 9?years (33 to 70 per 1000) and lowest in adults aged 18-49?years (21 to 27 per 1000). Cases averted ranged from 9 per 1000 vaccinees (Washington, 2014/15) to 28 per 1000 (Wisconsin, 2013/14). DISCUSSION:Seasonal influenza epidemics cause a considerable burden of outpatient medical visits. The United States influenza vaccination program has caused meaningful reductions in outpatient visits for influenza, even in years when the vaccine is not well-matched to the dominant circulating influenza strain.

| S-EPMC5843364 | biostudies-literature

Factors Associated With Prolonged Viral Shedding in Patients With Avian Influenza A(H7N9) Virus Infection.

Project description:BackgroundData are limited on the impact of neuraminidase inhibitor (NAI) treatment on avian influenza A(H7N9) virus RNA shedding.MethodsIn this multicenter, retrospective study, data were collected from adults hospitalized with A(H7N9) infection during 2013-2017 in China. We compared clinical features and A(H7N9) shedding among patients with different NAI doses and combination therapies and evaluated factors associated with A(H7N9) shedding, using Cox proportional hazards regression.ResultsAmong 478 patients, the median age was 56 years, 71% were male, and 37% died. The median time from illness onset to NAI treatment initiation was 8 days (interquartile range [IQR], 6-10 days), and the median duration of A(H7N9) RNA detection from onset was 15.5 days (IQR, 12-20 days). A(H7N9) RNA shedding was shorter in survivors than in patients who died (P < .001). Corticosteroid administration (hazard ratio [HR], 0.62 [95% confidence interval {CI}, .50-.77]) and delayed NAI treatment (HR, 0.90 [95% CI, .91-.96]) were independent risk factors for prolonged A(H7N9) shedding. There was no significant difference in A(H7N9) shedding duration between NAI combination treatment and monotherapy (P = .65) or between standard-dose and double-dose oseltamivir treatment (P = .70).ConclusionsCorticosteroid therapy and delayed NAI treatment were associated with prolonged A(H7N9) RNA shedding. NAI combination therapy and double-dose oseltamivir treatment were not associated with a reduced A(H7N9) shedding duration as compared to standard-dose oseltamivir.

| S-EPMC6679685 | biostudies-literature

Viral etiology of medically attended influenza-like illnesses in children less than five years old in Suzhou, China, 2011-2014.

Project description:Limited information is available on the non-influenza etiology and epidemiology of influenza-like illness (ILI) in China. From April 2011 to March 2014, we collected oropharyngeal swabs from children less than 5 years of age with symptoms of ILI who presented to the outpatient departments of Suzhou University Affiliated Children's Hospital (SCH). We used reverse transcription polymerase chain reaction (rt-PCR) or PCR to detect 11 respiratory viruses. Among 3,662 enrolled ILI patients, 1,292 (35.3%) tested positive for at least one virus. Influenza virus (16.9%) was detected most frequently (influenza A 7.4%, influenza B 9.5%), followed by respiratory syncytial virus (RSV) (5.6%), parainfluenza virus (PIV) types 1-4 (4.8%), human bocavirus (HBoV) (3.8%), human metapneumovirus (HMPV) (3.5%), and adenovirus (ADV) (3.0%). Co-infections were identified in 108 (2.9%) patients. Influenza virus predominantly circulated in January-March and June-July. The 2013-2014 winter peaks of RSV and influenza overlapped. Compared with other virus positive cases, influenza positive cases were more likely to present with febrile seizure, and RSV positive cases were more likely to present with cough and wheezing, and were most frequently diagnosed with pneumonia. These data provide a better understanding of the viral etiology of ILI among children less than 5 years of age in Suzhou, China. Influenza is not only the most frequently identified pathogen but it is also the only vaccine preventable illness among the 11 pathogens tested. Such findings suggest the potential value of exploring value of influenza vaccination among this influenza vaccination target group. J. Med. Virol. 88:1334-1340, 2016. © 2016 Wiley Periodicals, Inc.

| S-EPMC7166643 | biostudies-literature

Impact of Statins on Influenza Vaccine Effectiveness Against Medically Attended Acute Respiratory Illness.

Project description:BackgroundStatins have antiinflammatory effects that may impact vaccine-induced immune responses. We investigated the impact of statin therapy on influenza vaccine effectiveness (VE) against medically attended acute respiratory illness (MAARI).MethodsWe conducted a retrospective cohort study over nine influenza seasons using research databases of a large managed care organization in the United States. Influenza vaccination and statin prescription statuses of cohort members and MAARI cases were ascertained on a per-season basis. Incidence rate ratios (IRRs) of MAARI were estimated using Poisson regression and stratified by statin use. Using a ratio of ratios approach, we compared IRRs from periods during to IRRs from periods before influenza circulation and then used relative IRRs to compute VE.ResultsAfter adjustment for multiple prespecified covariates, the influenza VE against MAARI was lower among statin users than nonusers during periods of local (14.1% vs 22.9%; mean difference, 11.4%; 95% confidence interval [CI], -1.7% to 26.1%) and widespread (12.6% vs 26.2%; mean difference, 18.4%; 95% CI, 2.9%-36.2%) influenza circulation.ConclusionsIn this study, statin therapy was associated with reduced influenza VE against MAARI. Since many cases of MAARI are not caused by influenza, studies of the impact of statins on influenza VE against laboratory-confirmed influenza are needed.

| S-EPMC4799662 | biostudies-literature

Estimation of influenza- and respiratory syncytial virus-attributable medically attended acute respiratory infections in Germany, 2010/11-2017/18.

Project description:BACKGROUND:The burden of influenza in primary care is difficult to assess, since most patients with symptoms of a respiratory infection are not tested. The case definition of "medically attended acute respiratory infection" (MAARI) in the German physician sentinel is sensitive; however, it requires modelling techniques to derive estimates of disease attributable to influenza and respiratory syncytial virus (RSV). OBJECTIVES:The objective of this paper was to review and extend our previously published model in order to estimate the burden of RSV and the differential burden of the two influenza B lineages (Victoria, Yamagata) as well as both influenza A subtypes on primary care visits. METHODS:Data on MAARI and virological results of respiratory samples (virological sentinel) were available from 2010/11 until 2017/18. We updated the previously published generalized additive regression model to include RSV. RESULTS:We found that the proportion of MAARI due to RSV is substantial only in the 0-1- and 2-4-year-old age groups (0-1 years old: median 7.5%, range 4.0%-14.8%; 2-4 years old: median 6.5%, range 4.0%-10.3%); in the 0-1 years old age group, RSV leads in almost all seasons to a higher burden than any influenza type or subtype, but this is reversed in the age group 2-4 years old. CONCLUSIONS:We succeeded in rearranging our previously published model on MAARI to incorporate RSV as well as the two influenza B lineages (Victoria, Yamagata) in the time period 2010 to 2018.

| S-EPMC6692544 | biostudies-literature

Comparison of the Outcomes of Individuals With Medically Attended Influenza A and B Virus Infections Enrolled in 2 International Cohort Studies Over a 6-Year Period: 2009-2015.

Project description:BackgroundOutcome data from prospective follow-up studies comparing infections with different influenza virus types/subtypes are limited.MethodsDemographic, clinical characteristics and follow-up outcomes for adults with laboratory-confirmed influenza A(H1N1)pdm09, A(H3N2), or B virus infections were compared in 2 prospective cohorts enrolled globally from 2009 through 2015. Logistic regression was used to compare outcomes among influenza virus type/subtypes.ResultsOf 3952 outpatients, 1290 (32.6%) had A(H1N1)pdm09 virus infection, 1857 (47.0%) had A(H3N2), and 805 (20.4%) had influenza B. Of 1398 inpatients, 641 (45.8%) had A(H1N1)pdm09, 532 (38.1%) had A(H3N2), and 225 (16.1%) had influenza B. Outpatients with A(H1N1)pdm09 were younger with fewer comorbidities and were more likely to be hospitalized during the 14-day follow-up (3.3%) than influenza B (2.2%) or A(H3N2) (0.7%; P < .0001). Hospitalized patients with A(H1N1)pdm09 (20.3%) were more likely to be enrolled from intensive care units (ICUs) than those with A(H3N2) (11.3%) or B (9.8%; P < .0001). However, 60-day follow-up of discharged inpatients showed no difference in disease progression (P = .32) or all-cause mortality (P = .30) among influenza types/subtypes. These findings were consistent after covariate adjustment, in sensitivity analyses, and for subgroups defined by age, enrollment location, and comorbidities.ConclusionsOutpatients infected with influenza A(H1N1)pdm09 or influenza B were more likely to be hospitalized than those with A(H3N2). Hospitalized patients infected with A(H1N1)pdm09 were younger and more likely to have severe disease at study entry (measured by ICU enrollment), but did not have worse 60-day outcomes.

| S-EPMC5740982 | biostudies-literature

Viral shedding and clinical illness in naturally acquired influenza virus infections.

Project description:Volunteer challenge studies have provided detailed data on viral shedding from the respiratory tract before and through the course of experimental influenza virus infection. There are no comparable quantitative data to our knowledge on naturally acquired infections.In a community-based study in Hong Kong in 2008, we followed up initially healthy individuals to quantify trends in viral shedding on the basis of cultures and reverse-transcription polymerase chain reaction (RT-PCR) through the course of illness associated with seasonal influenza A and B virus infection.Trends in symptom scores more closely matched changes in molecular viral loads measured with RT-PCR for influenza A than for influenza B. For influenza A virus infections, the replicating viral loads determined with cultures decreased to undetectable levels earlier after illness onset than did molecular viral loads. Most viral shedding occurred during the first 2-3 days after illness onset, and we estimated that 1%-8% of infectiousness occurs prior to illness onset. Only 14% of infections with detectable shedding at RT-PCR were asymptomatic, and viral shedding was low in these cases.Our results suggest that "silent spreaders" (ie, individuals who are infectious while asymptomatic or presymptomatic) may be less important in the spread of influenza epidemics than previously thought.

| S-EPMC3060408 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data