Influenzanet is a system to monitor the activity of influenza-like-illness (ILI) with the aid of volunteers via the internet

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Developing the framework for an epidemic forecast infrastructure.

The Seventh Framework Programme (FP7) bundles all research-related EU initiatives.

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Participating countries and volunteers:

The Netherlands 12247
Belgium 3992
Portugal 2146
Italy 0
Great Britain 9790
Sweden 8761
Austria 554
Switzerland 160
France 5964
Spain 1012
Ireland 351
Denmark 2904
InfluenzaNet is a system to monitor the activity of influenza-like-illness (ILI) with the aid of volunteers via the internet. It has been operational in The Netherlands and Belgium (2003-2017), Portugal (since 2005) and Italy (since 2008), and the current objective is to implement InfluenzaNet in more European countries.

In contrast with the traditional system of sentinel networks of mainly primary care physicians coordinated by the European Influenza Surveillance Scheme (EISS), InfluenzaNet obtains its data directly from the population. This creates a fast and flexible monitoring system whose uniformity allows for direct comparison of ILI rates between countries.

Any resident of a country where InfluenzaNet is implemented can participate by completing an online application form, which contains various medical, geographic and behavioural questions. Participants are reminded weekly to report any symptoms they have experienced since their last visit. The incidence of ILI is determined on the basis of a uniform case definition.

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Incidence of Influenza-Like Illness in Europe during the season 2017-2018 (download as csv )

In this page, the incidence curve for each country is shown. 

The incidence is calculated as follows: number of Influenza-Like Illness cases for each week / the number of active participants for each week. 

A case of ILI is defined based on a the sudden onset of reported symptoms and at least one of the four systemic symptoms (this is the definition used by the European Centers for Disease Control):

  • Fever and/or chills
  • Feeling tired or exhausted
  • Headache
  • Muscle pain

And at least one of the three respiratory symptoms:

  • Cough
  • Sore throat
  • Shortness of breath (dyspnoea)

The incidence results for each country are then compared with the incidence data collected by the national sentinel-based surveillance and aggregated by the European Centers for Disease Control

disclaimer: the results in this page are still preliminar.