I'd ignore it. Having leaked a few (less than a million, I'm sure) SNMP 'gets' because I fat-fingered a subnet mask, or let a traceroute-based discovery routine go awry, or was just plain curious...
What do folk do about persistent SNMP probers?
...I'd ignore it.
And then next week we have ten folk hammering every two minutes. And the
next week we have twenty. ... No thanks.
randy