Epidemiology and timing of seasonal influenza epidemics in the Asia-Pacific region, 2010-2017: implications for influenza vaccination programs.
Asia-Pacific
Epidemiology
FluNet
Influenza
Vaccination
Journal
BMC public health
ISSN: 1471-2458
Titre abrégé: BMC Public Health
Pays: England
ID NLM: 100968562
Informations de publication
Date de publication:
21 Mar 2019
21 Mar 2019
Historique:
received:
07
12
2018
accepted:
12
03
2019
entrez:
23
3
2019
pubmed:
23
3
2019
medline:
11
5
2019
Statut:
epublish
Résumé
Description of the epidemiology of influenza is needed to inform influenza vaccination policy. Here we examined influenza virus circulation in countries in the Asia-Pacific region and compared the timing of seasonal epidemics with the timing of influenza vaccination. Data were obtained from the World Health Organization (WHO) FluNet database for 2010-2017 for countries in the WHO Asia-Pacific region. Data from countries covering ≥5 consecutive seasons and ≥ 100 influenza positive cases per year were included. Median proportions of cases for each influenza virus type were calculated by country and season. The timing and amplitude of the epidemic peaks were determined by Fourier decomposition. Vaccination timing was considered appropriate for each country if it was recommended ≤4 months before the primary peak of influenza circulation. Seven hundred eleven thousand seven hundred thirty-four influenza cases were included from 19 countries. Peak circulation coincided with the winter seasons in most countries, although patterns were less clear in some countries in the inter-tropical area due to substantial secondary peaks. Influenza A/H3N2 dominated overall, but proportions of A and B strains varied by year and by country. Influenza B represented 31.4% of all cases. The WHO-recommended timing for influenza vaccination was appropriate in 12 countries. Vaccination timing recommendations were considered inappropriate in Laos, Cambodia, and Thailand, and were inconclusive for India, Sri Lanka, Singapore, and Vietnam due to unclear seasonality of influenza virus circulation. Influenza virus circulation varied considerably across the Asia-Pacific region with an unusually high burden of influenza B. The recommended timing for vaccination was appropriate in most countries, except for several countries with unclear seasonality, mainly located in the inter-tropical area.
Sections du résumé
BACKGROUND
BACKGROUND
Description of the epidemiology of influenza is needed to inform influenza vaccination policy. Here we examined influenza virus circulation in countries in the Asia-Pacific region and compared the timing of seasonal epidemics with the timing of influenza vaccination.
METHODS
METHODS
Data were obtained from the World Health Organization (WHO) FluNet database for 2010-2017 for countries in the WHO Asia-Pacific region. Data from countries covering ≥5 consecutive seasons and ≥ 100 influenza positive cases per year were included. Median proportions of cases for each influenza virus type were calculated by country and season. The timing and amplitude of the epidemic peaks were determined by Fourier decomposition. Vaccination timing was considered appropriate for each country if it was recommended ≤4 months before the primary peak of influenza circulation.
RESULTS
RESULTS
Seven hundred eleven thousand seven hundred thirty-four influenza cases were included from 19 countries. Peak circulation coincided with the winter seasons in most countries, although patterns were less clear in some countries in the inter-tropical area due to substantial secondary peaks. Influenza A/H3N2 dominated overall, but proportions of A and B strains varied by year and by country. Influenza B represented 31.4% of all cases. The WHO-recommended timing for influenza vaccination was appropriate in 12 countries. Vaccination timing recommendations were considered inappropriate in Laos, Cambodia, and Thailand, and were inconclusive for India, Sri Lanka, Singapore, and Vietnam due to unclear seasonality of influenza virus circulation.
CONCLUSIONS
CONCLUSIONS
Influenza virus circulation varied considerably across the Asia-Pacific region with an unusually high burden of influenza B. The recommended timing for vaccination was appropriate in most countries, except for several countries with unclear seasonality, mainly located in the inter-tropical area.
Identifiants
pubmed: 30898100
doi: 10.1186/s12889-019-6647-y
pii: 10.1186/s12889-019-6647-y
pmc: PMC6429768
doi:
Substances chimiques
Influenza Vaccines
0
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
331Références
Vaccine. 2008 Sep 12;26 Suppl 4:D45-8
pubmed: 19230159
BMC Public Health. 2012 Nov 15;12:982
pubmed: 23153033
Euro Surveill. 2013 Jan 31;18(5):null
pubmed: 23399423
Euro Surveill. 2013 Jan 31;18(5):null
pubmed: 23399424
Influenza Other Respir Viruses. 2013 Nov;7 Suppl 3:44-51
pubmed: 24215381
Western Pac Surveill Response J. 2013 Mar 03;4(3):51-9
pubmed: 24319615
J Med Virol. 2014 Jun;86(6):1017-25
pubmed: 24395730
Bull World Health Organ. 2014 May 1;92(5):318-30
pubmed: 24839321
Vaccine. 2015 Jan 1;33(1):246-51
pubmed: 24962752
Influenza Other Respir Viruses. 2015 Aug;9 Suppl 1:3-12
pubmed: 26256290
Vaccine. 2016 Apr 29;34(20):2371-7
pubmed: 27020713
PLoS One. 2016 Apr 27;11(4):e0153003
pubmed: 27119988
Vaccine. 2016 Oct 26;34(45):5400-5405
pubmed: 27646030
Clin Infect Dis. 2016 Dec 29;64(5):544-550
pubmed: 28039340
Vaccine. 2017 Feb 7;35(6):856-864
pubmed: 28081970
PLoS One. 2017 Mar 27;12(3):e0174592
pubmed: 28346498
Euro Surveill. 2017 Aug 31;22(35):null
pubmed: 28877844
Influenza Other Respir Viruses. 2018 May;12(3):383-411
pubmed: 29127742
Lancet. 2018 Mar 31;391(10127):1285-1300
pubmed: 29248255
Influenza Other Respir Viruses. 2018 May;12(3):344-352
pubmed: 29405575
PLoS One. 2018 Feb 21;13(2):e0193263
pubmed: 29466459
JAMA. 1998 Oct 21;280(15):1330-2
pubmed: 9794312