We're still No. 1.

According to security software vendor Sophos, the U.S. leads the rest of the world in relaying annoying and potential dangerous emailed-based spam, accounting for more than 18 percent of all spam traffic in the fourth quarter.

That's almost three times more than the next closest spam-spewing country, India (6.9 percent), and five- to six-fold more than the bottom half of Sophos' Dirty Dozen list of nations responsible for 60 percent of all spam messages.


" The US's domination of the list underlines the continuing problem of computers being compromised by hackers in the country, allowing them to be remotely controlled for criminal purposes without the owners' knowledge," Sophos security researchers said in the report.

More concerning for enterprises and consumers regardless of their location is the sharp spike in malicious spam -- the type that immediately affects PCs or mobile devices or redirects people to malware-laden websites -- that now accounts for almost 5 percent of all email traffic.

Brazil sets the pace among South American malware and spam-producing countries and checked in third on the list at 5 percent. Russia and the UK followed at 4.6 percent and 4.5 percent, respectively, followed by France, Italy, South Korea, Germany, Vietnam, Romania and Spain.

The rest of the world accounted for just over 40 percent of all spam traffic in the quarter.

Sophos researchers said the escalating volume and sophistication of spam campaigns is a direct result of users' interest in or desire for most of the products offered. It estimates more than 36 million Americans purchased prescription drugs from unlicensed online sellers, giving spammers every reason to ramp up their operations.

And if it's not their thirst for Viagra or discounted Lipitor, it's greed that's keep these spam operations in business. Whether it's the lure of "free" Apple gift cards or some quick cash for completing a bogus questionnaire, there appears to be no end to Internet users' naiveté or negligence.

"Spam is certainly here to stay, however the motivations and the methods are continuing to change in order to reap the greatest rewards for the spammers," Graham Cluley, a senior technology consultant at Sophos, said in the report. "What's becoming even more prevalent is the mailing of links to poisoned web pages – victims are tricked into clicking a link in an email, and then led to a site that attacks their computer with exploits or attempts to implant fake anti-virus software."

By continent, Europe led the pack with 32.1 percent of all spam traffic, followed by Asia (31.9 percent), North America (22.4 percent), South America (10.3 percent) and Africa (2 percent).

Larry Barrett is a senior editor at InternetNews.com, the news service of Internet.com, the network for technology professionals.

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