If you have 1000 PCs in your organisation, you can expect to get hit by a computer virus about 120 times this year.
So says the National Computer Security Association (NCSA) in its "1996 Computer Virus Prevalence Survey". According to the poll of 300 midsize and large companies and government agencies, the chances of encountering a virus today is about one in 100 PCs per month, about five to 10 times higher than early last year.
Occurrences of older viruses such as Form and Stealth have increased, but the most dramatic rise is for the Word.concept virus, a so-called "macro virus" that was unknown just a year ago. It infected 36% of the sites surveyed and was responsible for half of all virus encounters.
Word.concept rides in documents created by Microsoft's Word. Unlike other viruses, which typically load when a user boots from an infected floppy diskette, Word.concept macro code can travel as electronic mail. It can infect a PC when the document is opened.
"There is no question the No. 1 [virus] threat today is from macro viruses," says a security manager at a Fortune 100 manufacturer. He says his company, which he asked not to be named, had set up a very strong, centralised computer incident response office where users can go for help. That's lacking at many companies, he says.
The companies surveyed say three-quarters of viruses came from diskettes, and 15% came from unknown sources. Nine% of the viruses came from email attachments, which weren't a virus source before the creation of the Word.concept virus last year.
"Electronic mail and viruses weren't even an issue a year ago," says Peter Tippett, president of the NCSA in Carlisle, Pennsylvania. The NCSA estimates total losses in North America due to computer viruses last year at US$1 billion. They will amount to US$2 billion to US$3 billion this year, according to the NCSA.
In the survey, which was co-sponsored by Cheyenne Software in Roslyn Heights, New York, 97% of companies polled said they use antivirus software.
"Most companies say they own antivirus software for most of their machines," Tippett says. "But what this boils down to is, people aren't using it."
Another problem, Tippett says, is that often a PC is scanned for viruses only when it is booted, which allows it to become infected and pass along a virus to other machines between scans.
He says users should employ continuously running antivirus software, particularly to catch the new macro viruses.