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 11799
Belgium 3924
Portugal 1720
Italy 4287
Great Britain 4002
Sweden 3559
Germany 179
Austria 482
Switzerland 660
France 6215
Spain 995
Ireland 293
Denmark 1294
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 (since 2003), 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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Archived results

Previous results from Flusurvey

Last year's Flusurvey reveal that on average, people suffering from a flu-like illness loses the equivalent to two days of healthy life. Although most people recover from flu, it can make people feel very unwell and reduce their quality of life while they are ill. By combining this information with the length of illness reported, Anton Camacho, a Flusurvey researcher at the London School of Hygiene and Tropical Medicine has shown that having flu is equivalent to losing two days of healthy life. The research also established that the amount of healthy life lost to flu increased with age, severity of the symptoms and if the participant was a smoker. This research will be published later this flu season, but to see preliminary data, please see the file below, presented at The Lancet Public Health Conference, November 2013 at the Institute of Child Health 

2013/14 Flusurvey

Below you can see what influenced Flusurvey participant's chances of reporting a flu-like illness for the 2013-2014 flu season. Factors in green were protective against flu-like illness.  Factors in red increased the risk. Factors in blue showed no association with reporting a flu-like illness.

Week 10

Below you can see that reports of flu-like illness have increased in all age groups in the last week. This indicates that we might be seeing the start of a flu like illness across the UK. We'll monitor this closely and check back see whether it increases next week!

Here's how flu rates are looking amongst participants this week (week 11)


Where do Flusurvey participants come from?

The figure below shows where Flusurvey participants are based. London, the South, and the East are well represented, but we would like to get a larger proportion from the North, Northern Ireland and Wales.  We'd also like to have more children involved, please tell your friends!

In the twenty first week of last year's flu season, rates of flu-like illness were low.  The highest rates of flu like illness were in the North East, Southwest,  East Midlands, and Scotland. there were almost no cases in Wales so it is difficult to say what is going on there.

This figure shows the age distribution of all our participants by region for 2012-2013.   


These results show that there was no increased chance of reporting a flu-like illness in 2012-2013 in participants who took public transport as compared to participants who did not take public transport.  This finding was the same all across Europe.

The graph above compares two cohorts of individuals from 2012-2013: those who had the flu vaccine last season (blue) and those who didn't (red). To create this graph, we divided our participants into these two groups ("cohorts"), anonymously matching someone who was vaccinated with someone else who wasn't but was of the same age group and gender and had the same underlying health condition status. The weekly percentage reporting ILI is shown for both these groups. We would expect the two lines to diverge only when there is flu around (since we wouldn't expect the vaccine to protect against any ILI not caused by flu). This figure shows that vaccinated individuals were less likely to report ILI, especially during the peak of the flu season.

Weekly incidence of flu-like illness last year (2012-2013 flu season)

This figure shows the pattern of flu-like illness reported by Flusurvey participants in 2012/3. The grey shading shows the school holidays. Over the season you can see the peaks in illness, and the effect that school holidays had on stopping the epidemic. The bottom graph shows % positivity of cases of lab confirmed flu (data provided by the Respiratory DataMart System is a laboratory surveillance tool to monitor influenza and other respiratory viruses based on collated lab results from a network of Public Health England (PHE) and NHS laboratories in England. Respiratory swabs from primary and secondary care are tested for a variety of viruses using real time polymerase chain reaction (RT-PCR) assays. Weekly results are published in the PHE National Influenza Report /)

Will it be a bad flu year?

Last year there was very little flu around.  Here you can track how much flu-like illness our participants are reporting last year (2013/4) compared to the previous year (2012/3).  It looks like there was a very mild season last year.

Manflu - a myth!

The figure below shows the distribution of reported health scores in healthy participants, participants with colds, and participants with influenza-like illness (ILI) last year. Scores reported by men are in blue, by women in pink. It's clear that people with ILI report lower health than people with cold symptoms or no symptoms, but the scores are not noticeably different for men and women. We haven't found any evidence that men are likely to report feeling worse when they're ill; if anything, women seem to report lower health scores.

Flu-like illness around Europe, 2011-12

attack rate by country

Weekly incidence of flu-like illness last year (2012-2013 flu season)

This figure shows flu-like illness last year (2011-2012) as reported on the various Flusurvey sites across Europe. It shows that even in a season considered very low-flu, still nearly 30% of people reported some flu-like illness. There wasn't much difference between countries. Generally children had the highest rates of flu, and elderly the lowest. What will the picture be like this year? Help us to find out! (Archived 29/11/12)

Country codes: BE=Belgium; IT=Italy; NL=The Netherlands; PT=Portugal; SE=Sweden; UK=United Kingdom; FR=France