Didn’t know any of that about FB. Just looked up and on the University of Delaware site it says only Fireblight resistant pears should be grown in De. And it’s an Anjou, so not resistant. I have noticed before some (very minor amount) of leaves here and there that are dark and shriveled. I guess that might be FB. I guess I’ll not be doing any summer pruning.
With just a few scattered leaves, it’s most probably not FB.
While the tear is fresh, I’d prune off that torn stub with as close a proper thinning cut as you can with what is left. It will have much less exposed area to enclose.