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Student Life


BMJ 2004; 329 doi: (Published 01 September 2004) Cite this as: BMJ 2004;329:0409342
  1. Jon Simmons, research fellow in health informatics in plastic surgery1,
  2. Mark Lloyd, research fellow in health informatics in plastic surgery1,
  3. Helen McEvoy, research fellow in health informatics in plastic surgery1,
  4. Peter Butler, consultant plastic surgeion1,
  5. Simon Whithey, consultant plastic surgeion1
  1. 1Department of Plastic and Reconstructive Surgery, Royal Free Hospital, London

Did you know that your computer is at risk from infection with Trojan horses, viruses, and worms? Mark Lloyd and colleagues clarify the confusing names given to computer threats and offer practical advice on how to vaccinate your personal computer from cyberattack

Has your computer ever “crashed” unexpectedly just as you were sending an important assignment two minutes before the deadline? Have you ever found your internet access getting slower and slower and then disconnecting when you least expect it? Have you ever clicked on the “ignore” or “update later” button when your computer has recommended that you update your antivirus software? Your computer could be ill due to an infection with a virus, worm, or Trojan horse. Cyberdeath is increasing, and computer intensive care units at retail chain PC World are unable to cope with the number of admissions made on a daily basis.

Time bomb

Computer security has been compromised by a lack of foresight, resulting in a timebomb ready to explode when threats such as viruses and worms invade a system, wreaking havoc. McAfee, an antivirus software company, estimates that the next big outbreak could result in 2.2 million office days lost in downtime. Another report estimates that the next big computer virus attack in the United Kingdom could cost £2.1bn ($3.9bn; a3.1bn).1

What is a computer virus? What does it mean when your antivirus software spots a Trojan horse? How can you get rid of worms? The world of computer bugs has become littered with terms that create panic and confusion in most computer users.


Trojan horses; as popular then as they are today

Trojan horses

In cybermythology, once upon a time there was hacker who used a computer program that was malicious and destructive and hidden in an email (Trojan horse) to gain entrance to a PC and …

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