I Just Moved In Here & The Previous Owner Left

I just moved in here & the previous owner left her Feral 9wild cats) behind. One of the Momma cats has a whole in her side which is pussy. Someone told me it looks like a Brown recluse spider bit. I don't know what to do to help her. Do you have any ideas? I know she doesn't have any of her shots & has never been to a vet. I can not catch her or afford to take her to a vet. I love Tn. but people here don't seem to care about their animals. Can you help me help her??? Please ?