1) There is no active malware anymore.
2) Some of them are archived and some of them are system protected files or files stored in system restore points. You shouldn't worry about it.
3) If you can afford, then it is always good to pair your antivirus with antimalware solution like Zemana Anti-Malware. Antivirus products are generally good, but don't have a good remediation. That is where antimalware software can help you.