The United States remained the largest source of spam in the world in the second quarter of 2010 according to a recent Sophos report that lists the top 12 spam-relaying countries in the world.

The company reports says the U.S. continues its reign as the king of spam, relaying more than 15.2% of unsolicited email, an increase from 13.1% in the first quarter of 2010.

While the United States is the top spam relaying country in the world, Europe has taken over the crown from Asia as the top spam relaying continent. More than a one third (35.0%) of the world’s unsolicited junk email was relayed by Europe during the quarter, up from 31.2% in the first quarter. Asia was the second worst spam contributor during the quarter at 30.9% followed by North America (18.9%), South America (11.5%) and Africa (2.5%).

“It’s sad to see spam relayed via compromised European computers on the rise – the UK, France, Italy and Poland have all crept up the rankings since the start of the year,” said Graham Cluley, senior technology consultant at Sophos.

Sophos says that spam now accounts for a staggering 97% of all email received by business email servers, putting both a strain on resources and accounting for a huge amount of time to lost productivity. Used largely as a method for selling counterfeit or illicit goods such as fake pharmaceuticals, luxury watches and false diplomas, virtually all spam comes from malware-infected computers (called botnets or zombies) that are controlled by cybercriminals.

The top 12 spam-relaying countries in the first quarter of 2010, according to Sophos were:
  • United States - 15.2%
  • India - 7.7%
  • Brazil - 5.5%
  • United Kingdom - 4.6%
  • South Korea - 4.2%
  • France - 4.1%
  • Germany - 4.0%
  • Italy - 3.5%
  • Russia - 2.8%
  • Vietnam - 2.7%
  • Poland - 2.5%
  • Romania- 2.3%

The dirty dozen accounted for 40.9% of all spam in the quarter.

Experts at Sophos arrived at their conclusions by examining spam messages it had received in the company's global network of spam traps during the second quarter of this year.

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