Evaluation of Nowcasting for Detecting and Predicting Local Influenza Epidemics, Sweden, 2009-2014

Emerg Infect Dis. 2018 Oct;24(10):1868-1873. doi: 10.3201/eid2410.171940.

Abstract

The growing availability of big data in healthcare and public health opens possibilities for infectious disease control in local settings. We prospectively evaluated a method for integrated local detection and prediction (nowcasting) of influenza epidemics over 5 years, using the total population in Östergötland County, Sweden. We used routine health information system data on influenza-diagnosis cases and syndromic telenursing data for July 2009-June 2014 to evaluate epidemic detection, peak-timing prediction, and peak-intensity prediction. Detection performance was satisfactory throughout the period, except for the 2011-12 influenza A(H3N2) season, which followed a season with influenza B and pandemic influenza A(H1N1)pdm09 virus activity. Peak-timing prediction performance was satisfactory for the 4 influenza seasons but not the pandemic. Peak-intensity levels were correctly categorized for the pandemic and 2 of 4 influenza seasons. We recommend using versions of this method modified with regard to local use context for further evaluations using standard methods.

Keywords: Sweden; epidemiology; evaluation research; human influenza; infectious disease; influenza; nowcasting; signal detection analysis; surveillance; viruses.

Publication types

  • Historical Article
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Epidemics
  • History, 21st Century
  • Humans
  • Influenza A Virus, H1N1 Subtype
  • Influenza A Virus, H3N2 Subtype
  • Influenza A virus / classification
  • Influenza A virus / genetics
  • Influenza, Human / epidemiology*
  • Influenza, Human / history
  • Influenza, Human / virology
  • Population Surveillance
  • Sweden / epidemiology