avast scan:
Files Tested: 5984
Detected: 5647
Nice, huh?
A total of detection rate: 94,36%. Not bad at all..
Submit the rest to avast!.. but first check if they are real malware with other scanners (per example: Malwarebytes) before the process of submit.
By the way, it was a quick scan? If not, which one?
And did you use default settings?