General consensus amongst the security community appears to be that most Spam/hackers are US or Eastern Europe based, they simply use poorly defended legacy systems in (IT) developing countries to generate the stuff.
Most of China for example, still uses either XP or China’s dodgy XP ripoff. Very easy to zombie and built into a net.
Most of the SPAM we get certainly appears to originate from Eastern Asia whereas actual malicious emails containing either viruses (relatively rare) or phishing links (very common), come from and point back to the old Russian federation.