Geographic representativeness for sentinel influenza surveillance: implications for routine surveillance and pandemic preparedness.
OBJECTIVE
To review the guidelines for geographic representativeness applied to sentinel influenza surveillance as proposed in the Framework for an Australian Influenza Pandemic Plan (1999).


METHODS
The number of sentinel practices, participating general practitioners and their consultation rates per 100,000 population, by region, were described for the Victorian sentinel surveillance system for 2003 and 2004. Influenza-like illness rates per 1,000 consultations were calculated for all participating practices and for a subset of regular participators. Indicators of seasonal influenza activity, set according to predefined thresholds, were compared in the two groups.


RESULTS
During these two influenza seasons, a subset of approximately one-quarter (27%) of participating practices provided almost half (45%) of the patient swabs and detected the same level of influenza activity over two influenza seasons as all participating practices. However, this subset of GPs recorded only 0.3% of all GP consultations in Victoria in 2004.


CONCLUSIONS
There should be an updated, evidence-based strategy for interpandemic influenza based on the number of general practice consultations. Requirements for surveillance during various pandemic phases also need to be reviewed.
Clothier
Hazel
H
Victorian Infectious Diseases Reference Laboratory, 10 Wreckyn Street, North Melbourne, Victoria 3051.
Turner
Joy
J
Hampson
Alan
A
Kelly
Heath
H
D004189:Disaster Planning; D005843:Geography; D017408:Guidelines as Topic; D006801:Humans; D007251:Influenza, Human / Q000453:epidemiology*; D018571:Sentinel Surveillance; D014739:Victoria / Q000453:epidemiology