INTRODUCTION: This report describes a 2011 seasonal influenza B outbreak in a metropolitan primary school in Australia with 179 students. METHODS: Epidemiological, microbiological and environmental investigations were undertaken. A retrospective cohort study was conducted using a questionnaire that included demographic data, details of illness, chronic health conditions and vaccination status. Influenza-like illness (ILI) was defined as fever plus cough and/or sore throat. Analysis of ILI was undertaken with the χ(2) test and Fisher's exact test. RESULTS: Seventy-two questionnaire respondents (75%) reported illness during the outbreak - 43 with ILI, giving an attack rate of 45%. There was no association between ILI and age or chronic lung disease. Six (6%) students were vaccinated against influenza before the outbreak; although four became ill, none satisfied the ILI case definition. Seven students were positive for influenza B including two confirmed as B/Brisbane/60/2008-like; one student was positive for rhinovirus and another for metapneumovirus. The recommended influenza vaccine matched the circulating influenza strains. DISCUSSION: This cohort study estimated a high ILI attack rate and demonstrated low influenza vaccine coverage within the setting of a primary school. Gastrointestinal symptoms, in addition to constitutional and respiratory symptoms, were common.
INTRODUCTION: This report describes a 2011 seasonal influenza B outbreak in a metropolitan primary school in Australia with 179 students. METHODS: Epidemiological, microbiological and environmental investigations were undertaken. A retrospective cohort study was conducted using a questionnaire that included demographic data, details of illness, chronic health conditions and vaccination status. Influenza-like illness (ILI) was defined as fever plus cough and/or sore throat. Analysis of ILI was undertaken with the χ(2) test and Fisher's exact test. RESULTS: Seventy-two questionnaire respondents (75%) reported illness during the outbreak - 43 with ILI, giving an attack rate of 45%. There was no association between ILI and age or chronic lung disease. Six (6%) students were vaccinated against influenza before the outbreak; although four became ill, none satisfied the ILI case definition. Seven students were positive for influenza B including two confirmed as B/Brisbane/60/2008-like; one student was positive for rhinovirus and another for metapneumovirus. The recommended influenza vaccine matched the circulating influenza strains. DISCUSSION: This cohort study estimated a high ILI attack rate and demonstrated low influenza vaccine coverage within the setting of a primary school. Gastrointestinal symptoms, in addition to constitutional and respiratory symptoms, were common.
Authors: Y Hirota; S Takeshita; S Ide; K Kataoka; A Ohkubo; S Fukuyoshi; K Takahashi; T Hirohata; M Kaji Journal: Int J Epidemiol Date: 1992-06 Impact factor: 7.196
Authors: Thi Thanh Le; Thu Hang Pham; Thi Hien Pham; Le Khanh Hang Nguyen; Co Thach Nguyen; Vu Mai Phuong Hoang; Thu Huong Tran; Vu Son Nguyen; Huong Giang Ngo; Quynh Mai Le Journal: Western Pac Surveill Response J Date: 2015-11-11