Just when you thought maybe, just maybe, the war on spam had turned in our favor, spam levels are rising again. The shut down of spammer haven McColo resulted in a dramatic 75% drop in spam levels, but now spammers have recovered and resumed their endless assault on our inboxes. This is largely courtesy of the  Mega-D botnet, which has been brough back to life. Nearly 97 billion pieces of spam were sent on Tuesday alone, which is rapidly approaching the average of 153 billion spams per day being sent before McColo was shut down. Interestingly Srizbi and Rustock, once two of the largest botnets, haven’t been able to recover as nicely. Some experts think the cybercriminals who ran them have moved on to something bigger and better. Only time will tell.

Experts also believe that the successful rebirth of Mega-D is due to the restructuring and modification of its infection techniques, some of which appear to have been borrowed from Rustock. It’s not yet known if this means the criminals behind Rustock are now running Mega-D or if the Mega-D gang simply copied from them.

Mega-D, named after one of the fake pharmaceuticals it promotes in the spam it sends, is most known for the ubiquitous “sexual enhancement” and Viagra spams it pumps out.