No evidence for man flu according to preliminary results from UK Flusurvey

London School of Hygiene & Tropical MedicineDec 19 2012

Preliminary results from the first month of the UK Flusurvey run by scientists at the London School of Hygiene & Tropical Medicine suggest there is no evidence for “man flu” and reveal that reports of flu-like illness are highest among children.

More than 4,000 people have signed up to the online health monitoring project since it launched a month ago.

Last week (week ending 16 December) the highest rates of flu were reported in the 0-18 age group, although the researchers running flusurvey.org.uk point out that this category has the lowest sample size of all the age groups (14%).

This ties in with evidence of an increase in flu in the 5-14 age group shown by the Health Protection Agency’s Weekly National Influenza Report of 13 December (GP consultation rate of 31.2 per 100,000 compared with 14.3 per 100,000 overall in England) and reports of outbreaks in schools.

Flusurvey data from previous years showed that people with children reported 14% more flu-like illness than people who did not have children.

With schools soon closing for the holidays, flu experts will be watching closely to see if reports of illness go up or down over the festive period.

Flusurvey researcher Professor John Edmunds, Head of the Department of Infectious Disease Epidemiology at the London School of Hygiene & Tropical Medicine, said: “Over Christmas we may be a bit more sociable than normal with drinks after work and parties but it’s difficult to say if this increases our risk of flu or not.

“If you look closely at GP reports of influenza-like-illness they sometimes level off or even decline a little over the Christmas holidays. This is probably because schools are closed, which will reduce virus transmission, or because some GP surgeries are closed so cases do not get reported.

“Reporting via Flusurvey will help us study these factors, especially as we are asking people to tell us how much social interaction they have had with other people each week. This should tell us whether our contacts really do change very much over the Christmas period, and whether that affects our risk.”

Among the other questions researchers want to explore is whether “man flu” exists.

While reports of seasonal flu are still at a low level, early analysis of data collected so far reveals that overall women report more flu-like symptoms than men – 11,200 per 100,000 women compared with 9,300 per 100,000 men.

Asked how they felt on a scale of 0-100 where 0 was the worst and 100 the best (the “man flu” question), the results showed the following:

• No difference between healthy men and women – the median score for both was 90
• No difference between men and women with cold symptoms (not influenza like illness) - median of 75 among women and 78 for men
• No difference between men and women who reported flu-like symptoms – median of 60 for both male and female participants

Dr Alma Adler, Research Fellow at the London School of Hygiene & Tropical Medicine, who is running the UK Flusurvey project, said: “The data are very preliminary and flu levels are still very low but overall the results suggest that contrary to what we expected to find, there is no such thing as man flu.

“The next step is to find out if there is a difference in perceived cause of illness – i.e. do men and women report this differently? For example, are men more likely to claim they have flu when they actually do not have symptoms consistent with flu.

“We appeal to people to take part in the Flusurvey to help us answer these questions and more and increase our understanding of seasonal flu.”

Other preliminary findings include:

• Last week the lowest incidence was in the over-65s
• Marginally more men (37.4%) versus women (35.7%) vaccinated
• This year there is higher incidence than the same time last year. This week - 16,000 per 100,000 (0-20 years); 9,000 per 100,000 (20-44) and 5,000 per 100,000 (45+) versus same time last year: 7,000 per 100,000 (0-20 year olds); 6,000 per 100,000 (20-44 year olds) and 4,000 per 100,000 (44+)

The annual UK Flusurvey aims to collect data from men and women of all ages around the country, in order to map trends as seasonal flu takes hold, enabling researchers to analyse how the virus spreads and who it affects. Anyone can take part in Flusurvey and it only takes a couple of minutes each week.

The online questionnaire at flusurvey.org.uk allows people to report their symptoms directly and the data are supplied to the Health Protection Agency’s national surveillance programmes.