Dataset Information

Distribution of influenza virus types by age using case-based global surveillance data from twenty-nine countries, 1999-2014.

ABSTRACT:

Background

Influenza disease burden varies by age and this has important public health implications. We compared the proportional distribution of different influenza virus types within age strata using surveillance data from twenty-nine countries during 1999-2014 (N=358,796 influenza cases).

Methods

For each virus, we calculated a Relative Illness Ratio (defined as the ratio of the percentage of cases in an age group to the percentage of the country population in the same age group) for young children (0-4 years), older children (5-17 years), young adults (18-39 years), older adults (40-64 years), and the elderly (65+ years). We used random-effects meta-analysis models to obtain summary relative illness ratios (sRIRs), and conducted meta-regression and sub-group analyses to explore causes of between-estimates heterogeneity.

Results

The influenza virus with highest sRIR was A(H1N1) for young children, B for older children, A(H1N1)pdm2009 for adults, and (A(H3N2) for the elderly. As expected, considering the diverse nature of the national surveillance datasets included in our analysis, between-estimates heterogeneity was high (I²>90%) for most sRIRs. The variations of countries' geographic, demographic and economic characteristics and the proportion of outpatients among reported influenza cases explained only part of the heterogeneity, suggesting that multiple factors were at play.

Conclusions

These results highlight the importance of presenting burden of disease estimates by age group and virus (sub)type.

SUBMITTER: Caini S

PROVIDER: S-EPMC5994061 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Publications

Distribution of influenza virus types by age using case-based global surveillance data from twenty-nine countries, 1999-2014.

Caini Saverio S Spreeuwenberg Peter P Kusznierz Gabriela F GF Rudi Juan Manuel JM Owen Rhonda R Pennington Kate K Wangchuk Sonam S Gyeltshen Sonam S Ferreira de Almeida Walquiria Aparecida WA Pessanha Henriques Cláudio Maierovitch CM Njouom Richard R Vernet Marie-Astrid MA Fasce Rodrigo A RA Andrade Winston W Yu Hongjie H Feng Luzhao L Yang Juan J Peng Zhibin Z Lara Jenny J Bruno Alfredo A de Mora Doménica D de Lozano Celina C Zambon Maria M Pebody Richard R Castillo Leticia L Clara Alexey W AW Matute Maria Luisa ML Kosasih Herman H Nurhayati Puzelli Simona S Rizzo Caterina C Kadjo Herve A HA Daouda Coulibaly C Kiyanbekova Lyazzat L Ospanova Akerke A Mott Joshua A JA Emukule Gideon O GO Heraud Jean-Michel JM Razanajatovo Norosoa Harline NH Barakat Amal A El Falaki Fatima F Huang Sue Q SQ Lopez Liza L Balmaseda Angel A Moreno Brechla B Rodrigues Ana Paula AP Guiomar Raquel R Ang Li Wei LW Lee Vernon Jian Ming VJM Venter Marietjie M Cohen Cheryl C Badur Selim S Ciblak Meral A MA Mironenko Alla A Holubka Olha O Bresee Joseph J Brammer Lynnette L Hoang Phuong Vu Mai PVM Le Mai Thi Quynh MTQ Fleming Douglas D Séblain Clotilde El-Guerche CE Schellevis François F Paget John J

BMC infectious diseases 20180608 1

<h4>Background</h4>Influenza disease burden varies by age and this has important public health implications. We compared the proportional distribution of different influenza virus types within age strata using surveillance data from twenty-nine countries during 1999-2014 (N=358,796 influenza cases).<h4>Methods</h4>For each virus, we calculated a Relative Illness Ratio (defined as the ratio of the percentage of cases in an age group to the percentage of the country population in the same age grou ...[more]

PMID: 29884140

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Dataset Information

Distribution of influenza virus types by age using case-based global surveillance data from twenty-nine countries, 1999-2014.

Background

Methods

Results

Conclusions

Publications

Distribution of influenza virus types by age using case-based global surveillance data from twenty-nine countries, 1999-2014.

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