Almost 40 per cent of European teenagers are unconcerned by the risks of viruses and other threats when downloading music or video content, according to a survey by a security vendor.
"A quarter don't worry about internet security and a third rarely check to see if their security software is up to date," said a spokesman for McAfee.
"Worryingly, 21 per cent of these teenagers are entrusted by their family to keep the family PC secure."
While most teenagers understood and recognised the term 'virus', just over a third of European teenagers admitted that they do not scan downloaded files or email attachments before opening them.
A staggering 79 per cent of those questioned were unaware of phishing scams.
The study questioned 615 teenagers aged 13-17 across the UK, France, Germany, The Netherlands, Spain and Italy.
Britain came top for having the most security aware teens in Europe. Dutch teenagers were the most carefree with 52 per cent not worried about internet security when they go online.
The Dutch are also Europe's biggest file sharers, with three quarters regularly downloading from illegal file sharing sites.
McAfee's research reveals widespread ignorance among teenagers. Some 46 per cent are unaware that a breach could cause them to lose all their digitally archived items such as music and photos, and 43 per cent are oblivious that their PC could be controlled remotely.
"Teens are advanced and heavy internet users but, as this research shows, they do not fully appreciate the consequences of online threats," said Sarah Whipp, senior director of marketing at McAfee EMEA.
"Parents need to understand the potential risks of having their children online, whether this is lost or stolen personal content or their own personal safety online, and educate them how to use the internet responsibly and carefully."
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