well I have a different point of view. I got Bitten by a large white tail(I found the spider and chatted briefly to it ) in my bed on my left ankle. It got worse and ulcerated for maybe 2 years, then went away slowly.
I had given up alcohol and I believe that helped. 10 years later I have been drinking again and the ulceration has erupted painfully and badly. Large and ugly. Info For those who are interested.
I also have a friend whose white tail bite gave him kidney failure and a mild heart attack as well as an ulcer larger than a dinner plate. Nasty little creepy crawlers.