Dataset Information

Epidemiological and virological characteristics of influenza B: results of the Global Influenza B Study.

ABSTRACT:

Introduction

Literature on influenza focuses on influenza A, despite influenza B having a large public health impact. The Global Influenza B Study aims to collect information on global epidemiology and burden of disease of influenza B since 2000.

Methods

Twenty-six countries in the Southern (n = 5) and Northern (n = 7) hemispheres and intertropical belt (n = 14) provided virological and epidemiological data. We calculated the proportion of influenza cases due to type B and Victoria and Yamagata lineages in each country and season; tested the correlation between proportion of influenza B and maximum weekly influenza-like illness (ILI) rate during the same season; determined the frequency of vaccine mismatches; and described the age distribution of cases by virus type.

Results

The database included 935 673 influenza cases (2000-2013). Overall median proportion of influenza B was 22·6%, with no statistically significant differences across seasons. During seasons where influenza B was dominant or co-circulated (>20% of total detections), Victoria and Yamagata lineages predominated during 64% and 36% of seasons, respectively, and a vaccine mismatch was observed in ≈25% of seasons. Proportion of influenza B was inversely correlated with maximum ILI rate in the same season in the Northern and (with borderline significance) Southern hemispheres. Patients infected with influenza B were usually younger (5-17 years) than patients infected with influenza A.

Conclusion

Influenza B is a common disease with some epidemiological differences from influenza A. This should be considered when optimizing control/prevention strategies in different regions and reducing the global burden of disease due to influenza.

SUBMITTER: Caini S

PROVIDER: S-EPMC4549097 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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Publications

Epidemiological and virological characteristics of influenza B: results of the Global Influenza B Study.

Caini Saverio S Huang Q Sue QS Ciblak Meral A MA Kusznierz Gabriela G Owen Rhonda R Wangchuk Sonam S Henriques Cláudio M P CM Njouom Richard R Fasce Rodrigo A RA Yu Hongjie H Feng Luzhao L Zambon Maria M Clara Alexey W AW Kosasih Herman H Puzelli Simona S Kadjo Herve A HA Emukule Gideon G Heraud Jean-Michel JM Ang Li Wei LW Venter Marietjie M Mironenko Alla A Brammer Lynnette L Mai Le Thi Quynh le TQ Schellevis François F Plotkin Stanley S Paget John J

Influenza and other respiratory viruses 20150801

<h4>Introduction</h4>Literature on influenza focuses on influenza A, despite influenza B having a large public health impact. The Global Influenza B Study aims to collect information on global epidemiology and burden of disease of influenza B since 2000.<h4>Methods</h4>Twenty-six countries in the Southern (n = 5) and Northern (n = 7) hemispheres and intertropical belt (n = 14) provided virological and epidemiological data. We calculated the proportion of influenza cases due to type B and Victori ...[more]

PMID: 26256290

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Dataset Information

Epidemiological and virological characteristics of influenza B: results of the Global Influenza B Study.

Introduction

Methods

Results

Conclusion

Publications

Epidemiological and virological characteristics of influenza B: results of the Global Influenza B Study.

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