This year I have a pretty heavy infestation of parasites(red sores) on my CPNBG and LMB but the BC seem to be parasite free.

My insurance agent came over yesterday to fish and we caught 26 BC and none had parasites. I wanted to show him the CPNBG and every 3rd fish I caught had them. Also about 25% of the LMB have them.

So how can one species avoid infestation?
Do the parasites/sores on the CPNBG & BC go away?