In Net::IMAP CPAN docs, did you see this:

* recent 
The number of messages with the \recent flag set.
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It is under the status $mailbox, @statusattrs heading. You may also want to look into Mail::IMAPClient. According to the docs, Mail::IMAPclient has a recent option as well.. Hope this helps you...

UPDATE: A bit more verbose in reply.

-- Can't never could do anything, so give me and inch, I'll make it a mile.