This sort of malware problem only gets worse and has done over the last four or five years. The issue lies with the fact there are a large ammount of the general populous who have no common sense what so ever, and will blindly click on files contained within emails, download attachments, oblige in handing over vital personal banking details to fraudulent phishing websites ect.
Botnets are getting worse aswell because these users are not properly protected against such attacks or do not even know thier systems are compromised.
The answer to the whole problem is education, it's far to easy to start using a computer these days without actually knowing about any of these risks.
A good solution would be an advice leaflet which came with every new personal computer or laptop advising consumers on good internet practice and how to avoid becoming a victim of fraudsters.