Global search

Find data and evidence

Type at least 2 characters. Use arrow keys to review and Enter to open.

Peer reviewedOpen accessInfluenza

The Epidemiology of Interpandemic and Pandemic Influenza in Vietnam, 2007–2010

American Journal of Epidemiology·

Peter Horby, Le Quynh Mai, Annette Fox, Pham Quang Thai, Nguyen Thi Thu Yen, Le Thi Thanh, Nguyen Le Khanh Hang, Tran Nhu Duong, Dang Dinh Thoang, Jeremy Farrar, Marcel Wolbers, Nguyen Tran Hien

DOI
10.1093/aje/kws121
PMID
22411862
PMCID
PMC3353138
OpenAlex
W2104725412
Study type
Cohort study
Publisher
Oxford University Press (OUP)
Article type
journal-article
Integrity
current

Why this research matters now

The observed heterogeneity in age-specific infection risk by subtype and season may affect the potential impact of school-based interventions such as school closure and childhood vaccination programs on influenza transmission in tropical regions like Vietnam.

01

Structured evidence summary

Research question

The study examined the epidemiology of influenza infection across interpandemic and pandemic periods in a tropical setting, addressing infection risk by age, sex, season, and viral subtype.

Study design

Prospective household-based cohort study with active influenza surveillance and intermittent seroprevalence surveys conducted in Vietnam from December 2007 to April 2010, yielding 1,793 person-seasons of observation.

Population and setting

Community-dwelling households in Vietnam, with primary analysis focused on individuals aged 5 years and older.

Main findings

Age- and sex-standardized seasonal influenza infection risk in persons 5 years and older ranged from 17.0% to 26.4% across three surveillance seasons. The highest infection risk (41.8% per season) occurred in children aged 5-9 years. Multiple infections with different viral types or subtypes within a single season were documented in 27 individuals, and reinfection with the same subtype across seasons occurred in 22 individuals. Age-specific infection risk varied by viral subtype and season.

Public-health relevance

The observed heterogeneity in age-specific infection risk by subtype and season may affect the potential impact of school-based interventions such as school closure and childhood vaccination programs on influenza transmission in tropical regions like Vietnam.

Important limitations

This summary relies on the supplied single-article abstract and metadata. Complete assessment of study limitations, including sampling methods, loss to follow-up, case ascertainment sensitivity, generalizability beyond the study site, and potential confounding requires review of the full published article.

GIDS interpretation

This cohort study provides baseline epidemiologic data on influenza transmission patterns in a tropical community setting. The classifier links identify the article as relevant to influenza surveillance, transmission dynamics, vaccination strategy, and climate-related disease patterns in Vietnam. Such prospective cohort data may inform disease modeling and intervention planning but should not be interpreted as reflecting current or emerging outbreak activity.

02

Related GIDS surveillance

Literature context does not validate, explain, or change a surveillance signal. Exact and contextual relationships are shown separately.

03

Evidence relationships

This article has 14 auditable classifier relationships to diseases, places, topics, and study design.

about diseaseaddresses topicaddresses topicaddresses topicaddresses topicevaluates interventionhas pathogen typestudied instudied population settingstudies pathogenstudies populationstudies populationstudies populationuses study design