The Anomy Sanitizer is what most people would call “an email virus scanner”. That description is not totally accurate, but it does cover one of the more important jobs that the sanitizer can do for you - it can scan email attachments for viruses.

It is a rather old piece of software (the last 1.76 release is dated 2006), but it is still included in Debian 11 Bullseye and it can perform rather sofisticated email processing as a simple filter operation.

I use it as a personal mail filter in GNU/Linux mail servers, because it can be activated on a per-user basis, by the Local Delivery Agent called by Postfix. The LDA can be as simple as procmail or the more complex Dovecot LDA with Pigeonhole Sieve Interpreter.