Computer viruses, worms and Internet security

SIR, – With the increasing popularity of the Internet in the profession, I write with a warning to colleagues who use it. I have watched the virus threat change over the decades I have been using Computers. It used to be that infected ‘floppies’ had to be swapped between computers. Such viruses were easy to counter, and you just had to be careful about the source of the discs you put in your computer. Nowadays, e-mail is the way to spread viruses, and anyone from the ‘newbie’ to the experienced expert can unwittingly infect their computer and those of others. E-mail is being used extensively to allow easy communication within veterinary communities and specialities which are otherwise geographically separated. It is perhaps as easy as a fax to prepare and send, but a single message can be sent to hundreds of recipients. Many of today's users are relative newcomers and unaware of the security issues affecting their computer, making them particularly vulnerable to virus infection, and a single infected user can, in the space of a few seconds, propagate the latest virus or worm to hundreds of colleagues internationally. ‘Happy99’ was sent around the world by people thinking it was a fireworks display. It was, but while it was showing the fireworks, it also used the computer's address book to send 50 copies of itself to others. The recent ‘Love Bug’ tricked people into thinking they had been sent a love letter. The worm attachment had a file name which fooled the more computersavvy users into activating it. More worrying is the oddly named KAK worm. This is an ‘Active X control’, which does not need express permission from the user - it can be activated by an HTML instruction within a formatted message; e-mail used to be plain text, but it can now be formatted just like a web page with programs which run when the page is read, and that is how this ‘worm’ spreads. Many viruses are aimed at PCs running Microsoft Windows. Viruses for other operating Systems, such as UNIX and Apple Macs, are much less common. These comments are mostly aimed at Windows users. Protection against viruses and worms requires a little knowledge, a little time, and a little care, but is easy to learn and to put in to practice. Care now can prevent a lot of time, hassle, data loss and, in some cases, international embarrassment later!