The numbers of Hezbollah fighters differs wildly according to who you ask:
“Western officials and analysts believe it has roughly 6,000 to 8,000 fighters on the ground there.” http://foreignpolicy.com/2015/07/09/syrian-war-takes-rising-toll-on-hezbollah/
That is still most of them wounded or dead.
1,500 + 5,000 = 6,500
A force with casualties that high would no longer exist.