Although down in recent months, around 150bn spam messages are sent every day, up 280 per cent from the same time last year, according to the latest quarterly Secure Computing Internet Threats Report (PDF).

"This year we've seen the threat landscape change considerably with a 280 per cent rise in spam," said Mike Smart, senior product manager for Secure Computing in EMEA.

"Volumes peaked on 27 March with 185 billion spam messages being sent in just one day."

According to the report, adverts for male enhancement products still account for nearly four out of every 10 spam messages, followed by knock-offs and cheap prescription drugs.

In an attempt to appeal to wider audiences spammers are also moving into new languages. Previously almost all spam was in English, but now half of all spam is in other languages, with Japanese and German being popular alternatives.

The report also notes the changing pattern in the threat landscape, with many cyber-criminals turning to more sophisticated and blended attacks to help circumvent software defences and better educated users.

"What is also striking about the threat landscape is the huge growth in malicious websites and the top categories of sites with malicious reputations, including spam URLs, pornography and portal sites," added Smart.

Perpetrators are continuing to use pop culture and current events to entice end users into responding or clicking on links whose sole purpose is to download malware.

According to Secure Computing, although the attack vectors may be changing the ultimate goal is the same, namely financial gain.