#Pandemic #vaccination #strategies and #influenza severe outcomes during the influenza #H1N1pdm09 pandemic and the post-pandemic influenza season: the Nordic experience (@eurosurveillanc, abstract)

[Source: Eurosurveillance, full page: (LINK). Abstract, edited.]

Eurosurveillance, Volume 21, Issue 16, 21 April 2016 / Surveillance and outbreak report

Pandemic vaccination strategies and influenza severe outcomes during the influenza A(H1N1)pdm09 pandemic and the post-pandemic influenza season: the Nordic experience

JG Cuesta 1 7 , P Aavitsland 2 , H Englund 3 , Ó Gudlaugsson 4 , SH Hauge 5 , O Lyytikäinen 6 , G Sigmundsdóttir 4 , A Tegnell 3 , M Virtanen 6 , the Nordic influenza comparison group 8 , TG Krause 1

Author affiliations: 1. Statens Serum Institut, Copenhagen, Denmark; 2. Epidemi, Kristiansand, Norway; 3. Public Health Agency Sweden, Stockholm, Sweden; 4. Centre for Health Security and Communicable Disease Control, Reykjavik, Iceland; 5. Norwegian Institute of Public Health, Oslo, Norway; 6. National Institute for Health and Welfare, Helsinki, Finland; 7. European Programme for Intervention Epidemiology Training (EPIET), European; Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden.; 8. The Nordic influenza comparison group members are listed at the end of the article

Correspondence: Julita Gil Cuesta (giljulita@gmail.com)

Citation style for this article: Cuesta JG, Aavitsland P, Englund H, Gudlaugsson Ó, Hauge SH, Lyytikäinen O, Sigmundsdóttir G, Tegnell A, Virtanen M, the Nordic influenza comparison group, Krause TG. Pandemic vaccination strategies and influenza severe outcomes during the influenza A(H1N1)pdm09 pandemic and the post-pandemic influenza season: the Nordic experience. Euro Surveill. 2016;21(16):pii=30208. DOI: http://dx.doi.org/10.2807/1560-7917.ES.2016.21.16.30208

Received:14 April 2015; Accepted:03 December 2015

 

Abstract

During the 2009/10 influenza A(H1N1)pdm09 pandemic, the five Nordic countries adopted different approaches to pandemic vaccination. We compared pandemic vaccination strategies and severe influenza outcomes, in seasons 2009/10 and 2010/11 in these countries with similar influenza surveillance systems. We calculated the cumulative pandemic vaccination coverage in 2009/10 and cumulative incidence rates of laboratory confirmed A(H1N1)pdm09 infections, intensive care unit (ICU) admissions and deaths in 2009/10 and 2010/11. We estimated incidence risk ratios (IRR) in a Poisson regression model to compare those indicators between Denmark and the other countries. The vaccination coverage was lower in Denmark (6.1%) compared with Finland (48.2%), Iceland (44.1%), Norway (41.3%) and Sweden (60.0%). In 2009/10 Denmark had a similar cumulative incidence of A(H1N1)pdm09 ICU admissions and deaths compared with the other countries. In 2010/11 Denmark had a significantly higher cumulative incidence of A(H1N1)pdm09 ICU admissions (IRR: 2.4; 95% confidence interval (CI): 1.9–3.0) and deaths (IRR: 8.3; 95% CI: 5.1–13.5). Compared with Denmark, the other countries had higher pandemic vaccination coverage and experienced less A(H1N1)pdm09-related severe outcomes in 2010/11. Pandemic vaccination may have had an impact on severe influenza outcomes in the post-pandemic season. Surveillance of severe outcomes may be used to compare the impact of influenza between seasons and support different vaccination strategies.

Keywords: Research; Abstracts; Pandemic Influenza; Vaccines; H1N1pdm09.

——

Advertisements

The influence of #corticosteroid #treatment on the #outcome of #influenza #H1N1pdm09 -related critical illness (Crit Care, abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Crit Care. 2016 Mar 30;20(1):75.

The influence of corticosteroid treatment on the outcome of influenza A(H1N1pdm09)-related critical illness.

Delaney JW1,2, Pinto R3, Long J3, Lamontagne F4, Adhikari NK1,5, Kumar A6,7,8,9, Marshall JC10, Cook DJ11, Jouvet P12, Ferguson ND1,13,14,15,16, Griesdale D17, Burry LD18, Burns KE1,19, Hutchison J20, Mehta S1,13,18, Menon K21, Fowler RA22,23; Canadian Critical Care Trials Group H1N1 Collaborative.

Author information: 1Interdepartmental Division of Critical Care Medicine, Department of Medicine, University of Toronto, Toronto, ON, Canada. 2Rouge Valley Health System, Scarborough, ON, Canada.  3Sunnybrook Hospital, Toronto, ON, Canada. 4Centre de recherche clinique Étienne-Le Bel, Université de Sherbrooke, Sherbrooke, PQ, Canada. 5Department of Critical Care Medicine, Sunnybrook Hospital, 2075 Bayview Avenue, Room D478, Toronto, ON, M4N 3M5, Canada. 6Section of Critical Care Medicine, Department of Internal Medicine, Faculty of Health Sciences, College of Medicine, University of Manitoba, Winnipeg, MB, Canada. 7Section of Infectious Diseases, Department of Internal Medicine, Faculty of Health Sciences, College of Medicine, University of Manitoba, Winnipeg, MB, Canada. 8Department of Medical Microbiology, Faculty of Health Sciences, College of Medicine, University of Manitoba, Winnipeg, MB, Canada. 9Department of, Faculty of Health Sciences, College of Medicine, University of Manitoba, Winnipeg, MB, Canada. 10St. Michael’s Hospital, University of Toronto, Toronto, ON, Canada. 11St. Joseph’s Hospital, McMaster University, Hamilton, ON, Canada. 12CHU Sainte Justine, Université de Montréal, Montréal, PQ, Canada. 13Department of Medicine, University of Toronto, Toronto, ON, Canada. 14Department of Physiology, University of Toronto, Toronto, ON, Canada. 15Division of Respirology, Department of Medicine, University Health Network and Mount Sinai Hospital, Toronto, ON, Canada. 16Critical Care Program, Department of Medicine, University Health Network and Mount Sinai Hospital, Toronto, ON, Canada. 17Vancouver General Hospital, University of British Columbia, Vancouver, BC, Canada. 18Mount Sinai Hospital, University of Toronto, Toronto, ON, Canada. 19Division of Critical Care, St. Michael’s Hospital, University of Toronto, Toronto, ON, Canada. 20Hospital for Sick Children, University of Toronto, Toronto, ON, Canada. 21Children’s Hospital of Eastern Ontario, University of Ottawa, Ottawa, ON, Canada. 22Interdepartmental Division of Critical Care Medicine, Department of Medicine, University of Toronto, Toronto, ON, Canada. rob.fowler@sunnybrook.ca. 23Department of Critical Care Medicine, Sunnybrook Hospital, 2075 Bayview Avenue, Room D478, Toronto, ON, M4N 3M5, Canada. rob.fowler@sunnybrook.ca.

 

Abstract

BACKGROUND:

Patients with 2009 pandemic influenza A(H1N1pdm09)-related critical illness were frequently treated with systemic corticosteroids. While observational studies have reported significant corticosteroid-associated mortality after adjusting for baseline differences in patients treated with corticosteroids or not, corticosteroids have remained a common treatment in subsequent influenza outbreaks, including avian influenza A(H7N9). Our objective was to describe the use of corticosteroids in these patients and investigate predictors of steroid prescription and clinical outcomes, adjusting for both baseline and time-dependent factors.

METHODS:

In an observational cohort study of adults with H1N1pdm09-related critical illness from 51 Canadian ICUs, we investigated predictors of steroid administration and outcomes of patients who received and those who did not receive corticosteroids. We adjusted for potential baseline confounding using multivariate logistic regression and propensity score analysis and adjusted for potential time-dependent confounding using marginal structural models.

RESULTS:

Among 607 patients, corticosteroids were administered to 280 patients (46.1 %) at a median daily dose of 227 (interquartile range, 154-443) mg of hydrocortisone equivalents for a median of 7.0 (4.0-13.0) days. Compared with patients who did not receive corticosteroids, patients who received corticosteroids had higher hospital crude mortality (25.5 % vs 16.4 %, p = 0.007) and fewer ventilator-free days at 28 days (12.5 ± 10.7 vs 15.7 ± 10.1, p < 0.001). The odds ratio association between corticosteroid use and hospital mortality decreased from 1.85 (95 % confidence interval 1.12-3.04, p = 0.02) with multivariate logistic regression, to 1.71 (1.05-2.78, p = 0.03) after adjustment for propensity score to receive corticosteroids, to 1.52 (0.90-2.58, p = 0.12) after case-matching on propensity score, and to 0.96 (0.28-3.28, p = 0.95) using marginal structural modeling to adjust for time-dependent between-group differences.

CONCLUSIONS:

Corticosteroids were commonly prescribed for H1N1pdm09-related critical illness. Adjusting for only baseline between-group differences suggested a significant increased risk of death associated with corticosteroids. However, after adjusting for time-dependent differences, we found no significant association between corticosteroids and mortality. These findings highlight the challenges and importance in adjusting for baseline and time-dependent confounders when estimating clinical effects of treatments using observational studies.

PMID: 27036638 [PubMed – as supplied by publisher]

Keywords: Research; Abstracts; H1N1pdm09; Seasonal Influenza; Corticosteroids.

——

#Effectiveness of seasonal #influenza #vaccine in preventing laboratory-confirmed influenza in primary care in the #UK: 2015/16 mid-season results (@eurosurveillanc, abstract)

[Source: Eurosurveillance, full page: (LINK). Abstract, edited.]

Eurosurveillance, Volume 21, Issue 13, 31 March 2016 / Research article

Effectiveness of seasonal influenza vaccine in preventing laboratory-confirmed influenza in primary care in the United Kingdom: 2015/16 mid-season results

R Pebody 1 , F Warburton 1 , J Ellis 1 , N Andrews 1 , A Potts 2 , S Cottrell 3 , J Johnston 4 , A Reynolds 2 , R Gunson 5 , C Thompson 1 , M Galiano 1 , C Robertson 6 , D Mullett 7 , N Gallagher 4 , M Sinnathamby 1 , I Yonova 7 8 , C Moore 3 , J McMenamin 2 , S de Lusignan 7 8 , M Zambon 1

Author affiliations: 1. Public Health England, London, United Kingdom; 2. Health Protection Scotland, Glasgow, United Kingdom; 3. Public Health Wales, Cardiff, United Kingdom; 4. Public Health Agency Northern Ireland, Belfast, United Kingdom; 5. West of Scotland Specialist Virology Centre, Glasgow, United Kingdom; 6. University of Strathclyde, Glasgow, United Kingdom; 7. University of Surrey, Guildford, United Kingdom; 8. Royal College of General Practitioners, Research and Surveillance Centre, London, United Kingdom

Correspondence: Richard Pebody (richard.pebody@phe.gov.uk)

Citation style for this article: Pebody R, Warburton F, Ellis J, Andrews N, Potts A, Cottrell S, Johnston J, Reynolds A, Gunson R, Thompson C, Galiano M, Robertson C, Mullett D, Gallagher N, Sinnathamby M, Yonova I, Moore C, McMenamin J, de Lusignan S, Zambon M. Effectiveness of seasonal influenza vaccine in preventing laboratory-confirmed influenza in primary care in the United Kingdom: 2015/16 mid-season results. Euro Surveill. 2016;21(13):pii=30179. DOI: http://dx.doi.org/10.2807/1560-7917.ES.2016.21.13.30179

Received:26 February 2016; Accepted:30 March 2016

 

Abstract

In 2015/16, the influenza season in the United Kingdom was dominated by influenza A(H1N1)pdm09 circulation. Virus characterisation indicated the emergence of genetic clusters, with the majority antigenically similar to the current influenza A(H1N1)pdm09 vaccine strain. Mid-season vaccine effectiveness (VE) estimates show an adjusted VE of 41.5% (95% confidence interval (CI): 3.0–64.7) against influenza-confirmed primary care consultations and of 49.1% (95% CI: 9.3–71.5) against influenza A(H1N1)pdm09. These estimates show levels of protection similar to the 2010/11 season, when this strain was first used in the seasonal vaccine.

Keywords: Research; Abstracts; Seasonal Influenza; Vaccines; H1N1pdm09; UK.

—–

The #infection of #turkeys and #chickens by #reassortants derived from #H1N1pdm09 and #avian #H9N2 #influenza viruses (Sci Rep., abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Sci Rep. 2015 Jun 1;5:10130. doi: 10.1038/srep10130.

The infection of turkeys and chickens by reassortants derived from pandemic H1N1 2009 and avian H9N2 influenza viruses.

Sun H1, Kong W1, Liu L1, Qu Y1, Li C1, Shen Y1, Zhou Y1, Wang Y1, Wu S1, Pu J1, Liu J1, Sun Y1.

 

Abstract

Outbreaks of pandemic H1N1 2009 (pH1N1) in turkeys have been reported in several countries. Co-infection of pH1N1 and avian H9N2 influenza viruses in turkeys provide the opportunity for their reassortment, and novel reassortant viruses might further be transmitted to other avian species. However, virulence and transmission of those reassortant viruses in poultry remain unclear. In the present study, we generated 16 single-gene reassortant influenza viruses including eight reassortants on the pH1N1 background by individual replacement with a corresponding gene segment from H9N2 and eight reassortants on the H9N2 background replaced individually with corresponding gene from pH1N1, and characterized reassortants viruses in turkeys and chickens. We found that the pH1N1 virus dramatically increased its infectivity and transmissibility in turkeys and chickens after introducing any gene (except for PB2) from H9N2 virus, and H9N2 virus acquired single gene (except for HA) of pH1N1 almost did not influence its replication and transmission in turkeys and chickens. Additionally, 13 reassortant viruses transmitted from turkeys to chickens. Our results indicate that turkeys and chickens are susceptible to pH1N1-H9N2 reassortant viruses, and mixing breeding of different avian species would facilitate the transmission of these reassortant viruses.

PMID: 26030097 [PubMed – indexed for MEDLINE] PMCID: PMC4603695 Free PMC Article

Keywords: Research; Abstracts; H1N1pdm09; H9N2; Reassortant Strain; Avian Influenza.

——-

#Characteristic #aminoacid #changes of #influenza #H1N1pdm09 #virus PA protein enhance #H7N9 viral #polymerase activity (Virus Genes, abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Virus Genes. 2016 Mar 15. [Epub ahead of print]

Characteristic amino acid changes of influenza A(H1N1)pdm09 virus PA protein enhance A(H7N9) viral polymerase activity.

Liu J1, Huang F1,2, Zhang J1, Tan L1, Lu G2, Zhang X3, Zhang H1.

Author information: 1Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, 74 Zhongshan 2nd Road, Guangzhou, 510080, Guangdong, China. 2Department of Respiration, Affiliated Guangzhou Women and Children’s Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, Guangdong, China. 3Institute of Human Virology, Key Laboratory of Tropical Disease Control of Ministry of Education, Zhongshan School of Medicine, Sun Yat-sen University, 74 Zhongshan 2nd Road, Guangzhou, 510080, Guangdong, China. zhxu22@mail.sysu.edu.cn.

 

Abstract

Human coinfection with a novel H7N9 influenza virus and the 2009 pandemic A(H1N1) influenza virus, H1N1pdm09, has recently been reported in China. Because reassortment can occur during coinfection, it is necessary to clarify the effects of gene reassortment between these two viruses. Among the viral ribonucleoprotein complex (vRNP) genes, only the PA gene of H1N1pdm09 enhances the avian influenza viral polymerase activity. Based on a phylogenetic analysis, we show a special evolutionary feature of the H1N1pdm09 PA gene, which clustered with those of the novel H7N9 virus and related H9N2 viruses, rather than in the outgroup as the H1N1pdm09 genes do on the phylogenetic trees of other vRNP genes. Using a minigenome system of the novel H7N9 virus, we further demonstrate that replacement of its PA gene significantly enhanced its polymerase activity, whereas replacement of the other vRNP genes reduced its polymerase activity. We also show that the residues of PA evolutionarily conserved between H1N1pdm09 and the novel H7N9 virus are associated with attenuated or neutral polymerase activity. The mutations associated with the increased activity of the novel H7N9 polymerase are characteristic of the H1N1pdm09 gene, and are located almost adjacent to the surface of the PA protein. Our results suggest that the novel H7N9 virus has more effective PB1, PB2, and NP genes than H1N1pdm09, and that H1N1pdm09-like PA mutations enhance the novel H7N9 polymerase function.

KEYWORDS: H7N9; Influenza A virus; Mutation; PA; Polymerase activity; Reassortment

PMID: 26980671 [PubMed – as supplied by publisher]

Keywords: Research; Abstracts; Avian Influenza; Seasonal Influenza; H1N1pdm09; H7N9.

——

#Age and #gender adjusted comparison of #clinical #features between severe cases infected with #H7N9 and #H1N1pdm influenza A in #Jiangsu Province, #China (PLoS One, abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

PLoS One. 2015 Mar 27;10(3):e0120999. doi: 10.1371/journal.pone.0120999. eCollection 2015.

Age and gender adjusted comparison of clinical features between severe cases infected with H7N9 and H1N1pdm influenza A in Jiangsu Province, China. [      ]

Huo X1, Xu K1, Dai Q1, Qi X1, Yu H1, Bao C1.

Author information: 1Department of Acute Infectious Disease, Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, China, 210009.

 

Abstract

BACKGROUND:

Influenza H7N9 and H1N1pdm can cause severe human infections. It is important to investigate the distinguishing clinical features between these two diseases. Several studies have compared the differences in general, however, age and gender adjusted comparisons may be more useful and informative to the health professionals.

METHODS:

A total of 184 severe H1N1pdm patients and 37 severe H7N9 patients from Jiangsu Province were included in this analysis to perform age and gender adjusted comparison of clinical features.

RESULTS:

After adjusting age and gender, no significant differences in chronic medical conditions or treatment were found between severely ill patients with H7N9 and H1N1pdm. Severely ill patients with H7N9 had significantly longer interval from onset of illness to neuraminidase inhibitor treatment and to death. They were more likely to have complications such as acute respiratory distress syndrome (ARDS), liver and renal dysfunctions, and had a significantly higher risk of death.

CONCLUSION:

Our results suggests that age and gender should be adjusted as important confounding factors when comparing the clinical features between severe H7N9 and H1N1pdm patients to avoid any misunderstanding regarding the differences between these two diseases particularly in terms of clinical severity and prognosis.

PMID: 25815732 [PubMed – indexed for MEDLINE]

PMCID: PMC4376887 Free PMC Article

Keywords: Research; Abstracts; Avian Influenza; Seasonal Influenza; H1N1pdm09; H7N9; Human; China; Jiangsu.

——-

Highly Predictive #Model for a Protective #Immune #Response to the #H1N1pdm09 #Influenza #Strain after Seasonal #Vaccination (PLoS One, #abstract)

[Source: PLoS One, full page: (LINK). Abstract, edited.]

Open Access / Peer-reviewed / Research Article

Highly Predictive Model for a Protective Immune Response to the A(H1N1)pdm2009 Influenza Strain after Seasonal Vaccination [      ]

Karsten Jürchott,  Axel Ronald Schulz,  Cecilia Bozzetti,  Dominika Pohlmann,  Ulrik Stervbo,  Sarah Warth,  Julia Nora Mälzer,  Julian Waldner,  … Brunhilde Schweiger,  Sven Olek

Published: March 8, 2016  / DOI: 10.1371/journal.pone.0150812

Abstract

Understanding the immune response after vaccination against new influenza strains is highly important in case of an imminent influenza pandemic and for optimization of seasonal vaccination strategies in high risk population groups, especially the elderly. Models predicting the best sero-conversion response among the three strains in the seasonal vaccine were recently suggested. However, these models use a large number of variables and/or information post- vaccination. Here in an exploratory pilot study, we analyzed the baseline immune status in young (<31 years, N = 17) versus elderly (≥50 years, N = 20) donors sero-negative to the newly emerged A(H1N1)pdm09 influenza virus strain and correlated it with the serological response to that specific strain after seasonal influenza vaccination. Extensive multi-chromatic FACS analysis (36 lymphocyte sub-populations measured) was used to quantitatively assess the cellular immune status before vaccination. We identified CD4+ T cells, and amongst them particularly naive CD4+ T cells, as the best correlates for a successful A(H1N1)pdm09 immune response. Moreover, the number of influenza strains a donor was sero-negative to at baseline (NSSN) in addition to age, as expected, were important predictive factors. Age, NSSN and CD4+ T cell count at baseline together predicted sero-protection (HAI≥40) to A(H1N1)pdm09 with a high accuracy of 89% (p-value = 0.00002). An additional validation study (N = 43 vaccinees sero-negative to A(H1N1)pdm09) has confirmed the predictive value of age, NSSN and baseline CD4+ counts (accuracy = 85%, p-value = 0.0000004). Furthermore, the inclusion of donors at ages 31–50 had shown that the age predictive function is not linear with age but rather a sigmoid with a midpoint at about 50 years. Using these results we suggest a clinically relevant prediction model that gives the probability for non-protection to A(H1N1)pdm09 influenza strain after seasonal multi-valent vaccination as a continuous function of age, NSSN and baseline CD4 count.

______

Citation: Jürchott K, Schulz AR, Bozzetti C, Pohlmann D, Stervbo U, Warth S, et al. (2016) Highly Predictive Model for a Protective Immune Response to the A(H1N1)pdm2009 Influenza Strain after Seasonal Vaccination. PLoS ONE 11(3): e0150812. doi:10.1371/journal.pone.0150812

Editor: Sang-Moo Kang, Georgia State University, UNITED STATES

Received: February 10, 2015; Accepted: February 20, 2016; Published: March 8, 2016

Copyright: © 2016 Jürchott et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Data Availability: All relevant data are within the paper and its Supporting Information files.

Funding: This work was funded by the following sources: Bundesministerium für Bildung und Forschung; http://www.bmbf.de/; Gerontosys Program (BMBF) – Primage. Project: KJ, AS, US, SO, AG, NB, AT, AUN. Bundesministerium für Bildung und Forschung; http://www.bmbf.de/; e:Med Program (BMBF) – e:Kid. Project: NB, AUN. EFRE grant “ProFit”: NB. Epiontis GmbH: SO. The funding organizations (BMBF and EFRE) had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript and only provided financial support in the form of authors’ salaries and/or research materials. Epiontis GmbH provided support in the form of salaries for authors (SO), but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of this author (SO) are articulated in the ‘author contributions’ section.

Competing interests: Epiontis GmbH provided support in the form of salaries for authors (SO), but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The authors have no further competing interests to declare relating to employment, consultancy, patents, products in development, marketed products or others. The commercial affiliation with Epiontis GmbH does not alter the authors’ adherence to PLOS ONE policies on sharing data and materials.

Keywords: Research; Abstracts; Seasonal Influenza; Vaccines; H1N1pdm09.

——