What is a virus?

A computer virus is a computer program, or segment of computer code, that has been created by someone to perform some malicious task on a computer when the instructions it contains are activated.

Some viruses will activate as soon as the infected file is opened, while others will lie dormant in the computer system until activated by a trigger, such as a specific date on the system clock, or the user performing a specific function like reading an email.

Viruses can be spread in a variety of ways:

• via email attachments
• resident on files on floppy disks or CDs
• downloaded from infected files sitting on websites on the Internet.

The best protection against computer viruses is to use anti-virus software that should be installed on your office and home computers, including laptops and notebooks. The anti-virus software should be updated regularly. Most anti-virus software includes free updates for licensed users that are available as automatic updates from the vendor website.  As new and powerful viruses are created almost daily, regular updating of your anti-virus software is essential to ensure your systems are protected from possible damage or infection.

Further Information

For more information on this security issue, you might like to look at the following

• Internet Industry Association's security portal website: http://www.security.iia.net.au/australian_resources/security_issues/viruses.html  
•  Internet Security Essentials Tip 2 - Install anti-virus software and keep it updated (89 kb)* 

*Source: Internet Security Essentials for Small Business, produced by DCITA.  For more information go to http://www.dcita.gov.au/communications_for_consumers/security/e-security/internet_security_essentials_for_small_business.

Where to go for commercial solutions and information

• Free-Firewall.org - www.free-firewall.org 
• McAfee - www.mcafee.com 
• Internet Security Systems - www.iss.net/netice 
• Symantec - www.symantec.com.au 
• Trend Micro - www.antivirus.com 
• ZoneAlarm - www.zonealarm.com

What to do

To protect your information and systems from virus attack:

• A virus scanning procedure should be documented, published communicated to all employees and enforced within the company.
• All desktop, laptop and notebook computers should have licensed and up-to-date anti-virus software installed.
• All internet email gateways and server points of access should have anti-virus scanning software installed.
• Documented processes and procedures should be available to all staff on what to do when a virus is detected or identified.
• System administrators must be alerted immediately to the presence of a virus in the system.  All infected files must be deleted or quarantined pending investigation of their source.

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