The UK has been ranked third in a table of countries with highest levels of active malware after a new market assessment published today by PandaLabs.

Once again Taiwan is rated as the country with the most active malware universe (29%), followed by the US (26%) and the UK (25%).

According to researchers working at Panda Security’s anti-malware laboratory, some five million new threats have been detected over the last three months, making it a record quarter for hackers.

Use of Trojan malware has rocketed by 71%, which is now responsible for causing more than 37% of all computer infections. 

The numbers of PCs infected also showed a rise 15% quarter on quarter, Panda said.

Apparently, September showed the highest ratio of PCs infected with active malware, not only in the third quarter, but throughout the whole year with levels touching 16%.

PandaLabs said it had also detected major growth in the distribution of malware through social networks.

The company noted it had monitored new variants of the Koobface worm in circulation during this latest quarter. “These new variants not only used Myspace and Facebook to spread, but also Twitter by posting malicious links from infected users’ accounts,” Panda said.