The fight against spam should include a complete set of measures to both protect users and counter the criminal organizations behind spam. The shutdown of the Pushdo and Cutwail botnets did not have a dramatic effect on the spam world, it did set off its own kind of chain reaction that impacted the volume of spam traffic over the autumn period. Law enforcement agencies in the Netherlands had struck several powerful blows against botnets comprised of computers infected with Bredolab. The most notable change in the geography of spam originated in the countries that were the recipients of the emails.”]
Source: https://securelist.com/a-short-sharp-shock-for-spam/36351/