Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Comparative Study
. 2010 Jun 29:10:37.
doi: 10.1186/1472-6947-10-37.

Detecting the start of an influenza outbreak using exponentially weighted moving average charts

Stefan H Steiner  1 , Kristina Grant, Michael Coory, Heath A Kelly
Affiliations
Comparative Study

Detecting the start of an influenza outbreak using exponentially weighted moving average charts

Stefan H Steiner et al. BMC Med Inform Decis Mak. .

Abstract

Background: Influenza viruses cause seasonal outbreaks in temperate climates, usually during winter and early spring, and are endemic in tropical climates. The severity and length of influenza outbreaks vary from year to year. Quick and reliable detection of the start of an outbreak is needed to promote public health measures.

Methods: We propose the use of an exponentially weighted moving average (EWMA) control chart of laboratory confirmed influenza counts to detect the start and end of influenza outbreaks.

Results: The chart is shown to provide timely signals in an example application with seven years of data from Victoria, Australia.

Conclusions: The EWMA control chart could be applied in other applications to quickly detect influenza outbreaks.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Victorian Weekly Laboratory Notifications of Influenza 2002-2008 With Shewhart Chart Threshold of 6.5.
Figure 2
Figure 2
EWMA with λ = 0.5 Applied to Victoria Laboratory Notification Data.
Figure 3
Figure 3
Histogram and Time Series Plot of the Laboratory Notifications in the Baseline Period.
Figure 4
Figure 4
Plot of the Baseline Average Run Length (ARL) by the threshold h.
Figure 5
Figure 5
Plot of the Average Run Length (ARL) in weeks by the Size of the Outbreak.
Figure 6
Figure 6
Comparison of ARL for EWMA, MA(4) and Shewhart Methods Solid line: EWMA, dashed line: MA(4), dashed dot line: Shewhart.
See this image and copyright information in PMC

References

    1. Newall AT, Wood JG, Macintyre CR. Influenza-related hospitalisation and death in Australians aged 50 years and older. Vaccine. 2008;26(17):2135–41. doi: 10.1016/j.vaccine.2008.01.051. - DOI - PMC - PubMed
    1. Kelly H, Carville K, Grant K, Jacoby P, Tran T, Barr I. Estimation of influenza vaccine effectiveness from routine surveillance data. PLoS One. 2009;4(3):e5079. doi: 10.1371/journal.pone.0005079. - DOI - PMC - PubMed
    1. Montgomery DC. Introduction to Statistical Quality Control. 6. John Wiley and Sons, New York; 2008.
    1. Woodall WH. The Use of Control Charts in Health-Care and Public-Health Surveillance (with discussion) Journal of Quality Technology. 2006;38:89–134.
    1. Tsui K-L, Chiu W, Gierlich P, Goldsman D, Liu X, Maschek T. A review of healthcare, public health and syndromic surveillance. Quality Engineering. 2008 online 1st October. 2008;20(4):435–50.

Publication types