Influenza 2010–2011: Lessons from the 2009 pandemic

Ison, Michael G.; Lee, Nelson

doi:10.3949/ccjm.77a.10135

Cited by 32 publications

(59 citation statements)

References 82 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Typically, severe progressive influenza diseases occur in patients who are of advanced age and have pre-existing, immunocompromising conditions. In early 2009, a novel influenza A/H1N1 virus (pH1N1) emerged and rapidly caused a pandemic [1], [2], [3], [4]. It has been estimated that in some populations, up to 20–40% of individuals were affected, and had resulted in excessive hospitalizations and deaths [1], [2], [4].…”

Section: Introductionmentioning

confidence: 99%

“…In early 2009, a novel influenza A/H1N1 virus (pH1N1) emerged and rapidly caused a pandemic [1], [2], [3], [4]. It has been estimated that in some populations, up to 20–40% of individuals were affected, and had resulted in excessive hospitalizations and deaths [1], [2], [4]. In the United States, 195,000–403,000 persons were hospitalized for severe pH1N1 infection, and 8,870–18,300 died by April 2010 [1], [2], [4], [5].…”

Section: Introductionmentioning

confidence: 99%

“…It has been estimated that in some populations, up to 20–40% of individuals were affected, and had resulted in excessive hospitalizations and deaths [1], [2], [4]. In the United States, 195,000–403,000 persons were hospitalized for severe pH1N1 infection, and 8,870–18,300 died by April 2010 [1], [2], [4], [5]. The pH1N1 virus has continued to co-circulate with the seasonal influenza viruses in the community [1], [3].…”

Section: Introductionmentioning

confidence: 99%

“…While most patients develop mild upper respiratory-tract infection with pH1N1, some may progress to develop severe lower respiratory-tract complications such as pneumonia [1], [2], [4], [5], [6]. In contrast to seasonal influenza, young adults and previously healthy individuals may also develop severe diseases [2], [4], [5], [6]. Among hospitalized adults, about 9–34% may require intensive care because of progressive respiratory failure, which can be associated with high mortality (14–46%); notably, some of the manifestations (e.g.…”

Section: Introductionmentioning

confidence: 99%

“…Among hospitalized adults, about 9–34% may require intensive care because of progressive respiratory failure, which can be associated with high mortality (14–46%); notably, some of the manifestations (e.g. ARDS, hemophagocytosis) are quite similar to those of H5N1 influenza [2], [4], [5], [6], [7], [8], [9].…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Cytokine Response Patterns in Severe Pandemic 2009 H1N1 and Seasonal Influenza among Hospitalized Adults

et al. 2011

Self Cite

View full text Add to dashboard Cite

BackgroundStudying cytokine/chemokine responses in severe influenza infections caused by different virus subtypes may improve understanding on pathogenesis.MethodsAdults hospitalized for laboratory-confirmed seasonal and pandemic 2009 A/H1N1 (pH1N1) influenza were studied. Plasma concentrations of 13 cytokines/chemokines were measured at presentation and then serially, using cytometric-bead-array with flow-cytometry and ELISA. PBMCs from influenza patients were studied for cytokine/chemokine expression using ex-vivo culture (Whole Blood Assay,±PHA/LPS stimulation). Clinical variables were prospectively recorded and analyzed.Results63 pH1N1 and 53 seasonal influenza patients were studied. pH1N1 patients were younger (mean±S.D. 42.8±19.2 vs 70.5±16.7 years), and fewer had comorbidities. Respiratory/cardiovascular complications were common in both groups (71.4% vs 81.1%), although severe pneumonia with hypoxemia (54.0% vs 28.3%) and ICU admissions (25.4% vs 1.9%) were more frequent with pH1N1. Hyperactivation of the proinflammatory cytokines IL-6, CXCL8/IL-8, CCL2/MCP-1 and sTNFR-1 was found in pH1N1 pneumonia (2–15 times normal) and in complicated seasonal influenza, but not in milder pH1N1 infections. The adaptive-immunity (Th1/Th17)-related CXCL10/IP-10, CXCL9/MIG and IL-17A however, were markedly suppressed in severe pH1N1 pneumonia (2–27 times lower than seasonal influenza; P−values<0.01). This pattern was further confirmed with serial measurements. Hypercytokinemia tended to be sustained in pH1N1 pneumonia, associated with a slower viral clearance [PCR-negativity: day 3–4, 55% vs 85%; day 6–7, 67% vs 100%]. Elevated proinflammatory cytokines, particularly IL-6, predicted ICU admission (adjusted OR 12.6, 95%CI 2.6–61.5, per log10unit increase; P = 0.002), and correlated with fever, tachypnoea, deoxygenation, and length-of-stay (Spearman's rho, P-values<0.01) in influenza infections. PBMCs in seasonal influenza patients were activated and expressed cytokines ex vivo (e.g. IL-6, CXCL8/IL-8, CCL2/MCP-1, CXCL10/IP-10, CXCL9/MIG); their ‘responsiveness’ to stimuli was shown to change dynamically during the illness course.ConclusionsA hyperactivated proinflammatory, but suppressed adaptive-immunity (Th1/Th17)-related cytokine response pattern was found in severe pH1N1 pneumonia, different from seasonal influenza. Cytokine/immune-dysregulation may be important in its pathogenesis.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Cytokine Response Patterns in Severe Pandemic 2009 H1N1 and Seasonal Influenza among Hospitalized Adults

et al. 2011

Self Cite

View full text Add to dashboard Cite

show abstract

A One-Step RT-PCR Array for Detection and Differentiation of Zoonotic Influenza Viruses H5N1, H9N2, and H1N1

Yao

Liu

LiJuan

et al. 2013

J. Clin. Lab. Anal.

View full text Add to dashboard Cite

The high sensitivity, rapidity, reproducibility, and specificity of this zoonotic influenza viruses rRT-PCR array has been verified as being sufficient to detect the presence of multiple zoonotic influenza viruses in a single assay. The zoonotic influenza viruses RT-PCR array might provide rapid identification of emergent zoonotic influenza viruses strains during influenza outbreaks and disease surveillance initiatives.

show abstract

Animal Models of Human Viral Diseases

Ruiz

Zumbrun

Nalca

2017

Animal Models for the Study of Human Disease

View full text Add to dashboard Cite

Influenza 2010–2011: Lessons from the 2009 pandemic

Abstract: Much was learned about the diagnosis, management, and pathogenesis of influenza from the 2009 pandemic of influenza A (H1N1). This knowledge can be applied to the management of people affected by seasonal infection and to future pandemics.

Cited by 32 publications

References 82 publications

Cytokine Response Patterns in Severe Pandemic 2009 H1N1 and Seasonal Influenza among Hospitalized Adults

Cytokine Response Patterns in Severe Pandemic 2009 H1N1 and Seasonal Influenza among Hospitalized Adults

A One-Step RT-PCR Array for Detection and Differentiation of Zoonotic Influenza Viruses H5N1, H9N2, and H1N1

Animal Models of Human Viral Diseases

Contact Info

Product

Resources

About