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

Saverio Caini (1) , Peter Spreeuwenberg (1) , Gabriela Kusznierz (2) , Juan Manuel Rudi (2) , Rhonda Owen (3) , Kate Pennington (4) , Sonam Wangchuk (5) , Sonam Gyeltshen (5) , Walquiria Aparecida Ferreira de Almeida (6) , Cláudio Maierovitch Pessanha Henriques (6) , Richard Njouom (7) , Marie-Astrid Vernet (7) , Rodrigo A Fasce (8) , Winston Andrade (8) , Hongjie Yu (9) , Luzhao Feng (10) , Juan Yang (10) , Zhibin Peng (10) , Jenny Lara (11) , Alfredo Bruno (12) , Domenica de Mora (12) , Celina de Lozano (13) , Maria Zambon (14) , Richard Pebody (14) , Leticia Le (15) , Alexey W Clara (16) , Maria Luisa Matute (17) , Herman Kosasih (18) , N Nurhayati (18) , Simona Puzelli (19) , Caterina Rizzo (19) , Herve A Kadjo (20) , Coulibaly Daouda (21) , Lyazzat Kiyanbekova (22) , Akerke Ospanova (22) , Joshua A Mott (23, 24) , Gideon O Emukule (23) , Jean-Michel Heraud (25) , Norosoa Harline Razanajatovo (25) , Amal Barakat (26) , Fatima El Falaki (26) , Sue Q Huang (27) , Liza Lopez (27) , Angel Balmaseda (28) , Brechla Moreno (29) , Ana Paula Rodrigues (30) , Raquel Guiomar (30) , Li Wei Ang (31) , Vernon Jian Ming Le (31) , Marietjie Venter (32, 33) , Cheryl Cohen (34, 35) , Selim Badur (36) , Meral A Ciblak (36) , Alla Mironenko (37) , Olha Holubka (37) , Joseph Bresee (38) , Lynnette Brammer (38) , Phuong Vu Mai Hoang (39) , Mai Thi Quynh Le (39) , Douglas Fleming (40) , Clotilde El-Guerche Séblain (41) , François Schellevis (1, 42) , John Paget (43) , Global Influenza B Study Group

1 Netherlands Institute for Health Services Research
2 Instituto Nacional de Enfermedades Respiratorias “Dr. Emilio Coni”
3 DHAISS - Department of Health and Ageing, Influenza Surveillance Section, Surveillance Branch, Office of Health Protection
4 DHAISS - Office of Health Protection, Woden, ACT, Australia
5 Ministry of Health [Bhoutan]
6 Ministry of Health [Brasília, Brazil]
7 Centre Pasteur du Cameroun
8 ISP - Instituto de Salud Pública de Chile
9 Chinese Centre for Disease Control and Prevention
10 Chinese Center for Disease Control and Prevention
11 Ministry of Health [Costa Rica]
12 INSPI - Instituto Nacional de Investigación en Salud Pública [Guayaquil, Ecuador]
13 MINSAL - Ministerio de Salud de El Salvador
14 Public Health England [London]
15 MSPAS - Ministerio de Salud Publica y Asistencia Social [Guatemala]
16 US Centers for Disease Control
17 SESAL - Ministry of Health [Honduras]
18 US Naval Medical Research Unit n°2
19 Istituto Superiore di Sanita [Rome]
20 Institut Pasteur de Côte d'Ivoire
21 INHP - Institut National d'Hygiène Publique [Côte d'Ivoire]
22 Astana Center of Sanitary Epidemiology Expertise
23 Centers for Disease Control and Prevention [Kenya]
24 USPHS - U.S. Public Health Service
25 IPM - Unité de Virologie [Antananarivo, Madagascar]
26 Ministry of Health [Morocco]
27 ESR - Institute of Environmental Science and Research
28 MINSA - Ministry of Health [Nicaragua]
29 National Influenza Center
30 INSA - Instituto Nacional de Saùde Dr Ricardo Jorge [Portugal]
31 Ministry of Health [Singapore]
32 Centers for Disease Control and Prevention
33 University of Pretoria [South Africa]
34 WITS - University of the Witwatersrand [Johannesburg]
35 NICD - National Institute for Communicable Diseases [Johannesburg]
36 Istanbul University
37 National Academy of Medical Sciences of Ukraine
38 CDC - Centers for Disease Control and Prevention [Atlanta]
39 NIHE - National Institute of Hygiene and Epidemiology [Hanoi, Vietnam]
40 Chercheur indépendant
41 Sanofi Pasteur [Lyon, France]
42 VU University Medical Center [Amsterdam]
43 Netherlands Institute for Health Services Research

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.

Keywords: Meta-analysis; Influenza; Influenza A virus; H3N2 subtype; Age distribution; H1N1 subtype; Influenza B virus

Domains: Life Sciences [q-bio]; Santé publique et épidémiologie; Life Sciences [q-bio]; Human health and pathology; Infectious diseases; Life Sciences [q-bio]; Human health and pathology; Emerging diseases; Life Sciences [q-bio]; Biochemistry, Molecular Biology; Molecular biology; Life Sciences [q-bio]; Microbiology and Parasitology; Virology

Saverio Caini, Peter Spreeuwenberg, Gabriela Kusznierz, Juan Manuel Rudi, Rhonda Owen, et al.. Distribution of influenza virus types by age using case-based global surveillance data from twenty-nine countries, 1999-2014. BMC Infectious Diseases, 2018, 18 (1), pp.269. ⟨10.1186/s12879-018-3181-y⟩. ⟨pasteur-01925131⟩