FluCAN 2009: initial results from sentinel surveillance for adult influenza and pneumonia in eight Australian hospitals
Kelly, PM and Kotsimbos, T and Reynolds, A and Wood-Baker, R and Hancox, B and Brown, SGA and Holmes, M and Simpson, G and Bowler, S and Waterer, G and Irving, LB and Jenkins, C and Thompson, PJ and Cheng, AC, FluCAN 2009: initial results from sentinel surveillance for adult influenza and pneumonia in eight Australian hospitals, Medical Journal of Australia, 194, (4) pp. 169-174. ISSN 0025-729X (2011) [Refereed Article]
Objective: To describe the epidemiology of adult patients hospitalised with influenza
or pneumonia during a pandemic season in a sentinel network in Australia.
Design, participants and setting: Prospective case series of adult hospital admissions
to eight acute care general public hospitals (Influenza Complications Alert Network
[Flu CAN] sentinel hospitals) in six Australian jurisdictions, 1 July to 4 December 2009.
Main outcome measures: Demographic, clinical and outcome measures in patients
admitted with laboratory-confirmed pandemic (H1N1) 2009 influenza in the sentinel
hospitals compared with data from national notifications and intensive care unit (ICU)
surveillance; admissions for influenza and pneumonia over time in each jurisdiction.
Results: During 190 hospital-weeks of observation, there were 538 influenza
admissions. Of these, 465 patients (86.4%) had the pandemic strain, representing
9.3% of total admissions with pandemic (H1N1) 2009 influenza (n = 4992) recorded
nationally in 2009. Of these patients, 250/465 (53.8%) were women, 67/453 (14.8%)
were Indigenous, and the median age was 46 years (interquartile range, 29–58 years).
Comorbidities were present in 354/464 patients (76.3%), and 40 were pregnant (30.3%
of women aged 15–49 years). FluCAN reported that 102 patients (21.9%) were admitted
to ICUs, and of patients admitted to hospital, 26 (5.6%) died. FluCAN results were very
similar to national notification data and published ICU admissions data. Of those who
were followed to 30 days after discharge, 30 (6.5%) were readmitted. Of 1468 patients
hospitalised with pneumonia, 718 (48.9%) were tested for influenza and 163 (11.1%) were
co-infected with the pandemic strain.
Conclusions: Sentinel surveillance systems can provide important and reliable
information in a timely fashion and can monitor changes in severity of influenza during a pandemic season.