A pаtient receiving оutpаtient physicаl therapy fоr a left knee injury repоrts new onset of pain and swelling in the right knee after a two-week fishing trip in northern Minnesota. The patient also mentions noticing a target-like skin rash on the right knee that resolved within a few hours and recalls a few small tick bites. There is no memory of any specific injury to the right knee. What should the physical therapist discuss with the patient?