Table 2.

Summary of website content by theme, month and source

Month	Epidemic	Information, prevention & treatment	Uncertainty & Mistrust
News sites & press
Febr 2012	Influenza activity low; increase in other European countries; criteria for epidemic; identifying the type of influenza.	Difference between flu and common cold; symptoms of flu; possible complications of an infection; variants of virus; severity of influenza; health effects of vaccination; vaccinated women and higher birth weight; prevention and treatment.	Uncertainty about effectiveness of vaccination; difficulty of proving effectiveness; collaboration between science, politics and pharmaceutical industry; dangerous effects of vaccination; spreading illness; narcolepsy as effect of the pandemic (H1N1) vaccine in 2009.
March 2012	Epidemic in south of the Netherlands; presence of epidemic; recognition of the flu; effectiveness of flu shot; complications for risk groups; decreasing influenza activity.	Only 70% of employees stayed at home when sick, possibly because of the economic crisis; information about virus and vaccine; Google flu; prevention, treatment and vaccination as the only effective protection.	Narcolepsy; collaboration between science and the pharmaceutical industry.
April 2012	End of epidemic; criteria for epidemic identification.	One nursing home with 30% infections.	Narcolepsy; loss of vaccines as a result of inaccurate storage.
Social media
Febr 2012	South of Netherlands closer to epidemic threshold (links to news sites); epidemic present (user experiences/ perceptions).	Difference between stomach flu and seasonal flu, viral and bacterial infection; Prevention (e.g. vitamin C&D); effectiveness flu shot (user experience).	Uncertainty about effectiveness of vaccination; ineffectiveness flu shot (user experience + links to websites); advice against vaccination.
March 2012	Late onset epidemic (links to news sites); presence of epidemic (links to news sites + user experience).	40% Dutch people have flu each year; less flu-related absenteeism because of economic crisis; work overload in hospitals during epidemic; vitamin D metabolism and flu; prevention; effectiveness flu shot (own experience).	Possibility of getting flu despite flu shot; economic background vaccination; ineffectiveness of flu shot; dangerousness of flu shot (e.g. Alzheimer, narcolepsy); collaboration between science and pharmaceutical industry.
April 2012	Epidemic present (own experience); end of epidemic (links to news sites).	Numbers of deaths epidemic 2012 (link to website); decreasing work absenteeism; effectiveness of flu shot (own experience).	Possibility of getting flu despite flu shot; ineffectiveness + dangerousness of flu shot; hygiene in workplace as means of prevention; discussion about loss of vaccines as a result of inaccurate storage.