The clamd-wrapper script (not part of upstream) contains the follow commands in the reload() function:

killproc -p ${CLAMD_PIDFILE} $procname -SIGHUP  || rc=$?
killproc -p ${CLAMD_PIDFILE} $procname -SIGUSR2 || rc=$?

However, these commands will always fail, because clamd-wrapper (properly) uses /bin/sh (instead of /bin/bash) for the shebang line, and when bash is invoked as /bin/sh instead of /bin/bash, for at least x86_64, the built-in kill() function does not support the SIG prefix for signal names:

$ ( /bin/bash -c 'kill -HUP $$' )
Hangup

$ ( /bin/sh -c 'kill -HUP $$' )
Hangup

$ ( /bin/bash -c 'kill -SIGHUP $$' )
Hangup

$ ( /bin/sh -c 'kill -SIGHUP $$' )
/bin/sh: line 0: kill: SIGHUP: invalid signal specification

Because the reload() function always fails, /usr/sbin/clamav-notify-servers always silently fails.

Arguably, this is a bug in bash... but traditionally, the "kill" program hasn't used the "SIG" prefix for signal names. (Perhaps there is a standard somewhere that defines this?)

At any rate, regardless of whether the behavior of bash is changed, for maximum portability (and more importantly, to avoid breakage), clamd-wrapper should not use the "SIG" prefix.

(I'm filing this bug against rawhide, but it affects all Fedora/EPEL releases.)