Format

Send to

Choose Destination
See comment in PubMed Commons below
J Clin Virol. 2011 Mar;50(3):235-9. doi: 10.1016/j.jcv.2010.11.012. Epub 2010 Dec 30.

Epidemiological investigation of an outbreak of pandemic influenza A (H1N1) 2009 in a boarding school: serological analysis of 1570 cases.

Author information

1
Guangzhou Center for Disease Control and Prevention, Zhongshan Road 3, No. 23, Guangzhou 510080, PR China.

Abstract

BACKGROUND:

A large number of 2009 pandemic influenza A (H1N1) infections were localized in school populations.

OBJECTIVES:

To describe the epidemiology, clinical features and risk factors associated with an outbreak that occurred at a vocational boarding school in Guangzhou, P.R. China.

STUDY DESIGN:

Data were collected prospectively and retrospectively through the use of on-site doctors and a post-outbreak survey and blood collection. The survey was used to confirm symptoms, and to investigate a series of flu-related factors such as dormitory conditions, health habits, vaccine history and population contact history. Blood samples were taken for serological analysis. Pandemic H1N1 infection was initially confirmed by a real-time RT-PCR assay. Following the identification of the outbreak by the Guangzhou CDC on September 4, cases were diagnosed symptomatically and retrospectively by serological analysis using the hemagglutination inhibition assay and a neutralization assay.

RESULTS:

The infection rate was 32% (505/1570) and the attack rate was 22.2% (349/1570). The asymptomatic infection rate was 9.9% (156/1570). Sharing a classroom (OR=2.17, 95% CI: 1.62-2.91) and dormitory space (OR=2.32, 95% CI: 1.84-2.93) was associated with higher rates of infection. Opening windows for ventilation was the only control measure that significantly protected against infection.

CONCLUSION:

Social isolation and quarantine should be used to prevent the spread of infection. Ventilation and a control of air flow between classrooms and dorms should be implemented as possible. School closures may be effective if implemented early.

PMID:
21195022
DOI:
10.1016/j.jcv.2010.11.012
[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center