Barracuda Email Security Gateway
Proofpoint Email Security and Protection
Symantec Email Security.cloud
Cisco Email Security
FortiMail
Area 1 Security
Security Gateway
Paubox
Mac Internet Security X9
Malwarebytes
Panda Antivirus for Mac
Clam Xav (desktop)
Avira
CleanMyMac X
Microsoft Security Essentials
Sophos Home
Proofpoint Email Security and Protection - Learn about Proofpoint's email security solutions that protect organizations against threats such as email fraud, phishing, spam, bulk email, and viruses.
Malwarebytes - Malwarebytes protects you against malware, ransomware, and other advanced online threats that have made antivirus obsolete and ineffective. Free Anti-Malware & Malware .
Symantec Email Security.cloud - Symantec Email Security.cloud provides always-on, inbound and outbound email security against malware, targeted attacks, and advanced threats
Panda Antivirus for Mac - A bare bones malware and anti-virus scanner.
Cisco Email Security - Cisco Email Security protects against ransomware, business email compromise, spoofing, and phishing.
Clam Xav (desktop) - Specifically with Clam Xav Sentry configured to scan inserted disks.Please read global comments on this question for an explanation of why desktop apps are being recommended for virus detection on ios devices.