Hitman Pro is an "on demand" virus detection app that doesn't even require installation, so no risk of conflicting with other antivirus/antimalware software.
From the developer's product page:
"No setup needed
HitmanPro is a signature-less on-demand malware scanner of just 10 MB and does not need to be installed. It can be started directly from an USB Flash Drive, CD/DVD, or network attached storage. This is particularly useful in case of a ransomware infection or in situations where malware is manipulating the installed antivirus software and its updates".