Do worse case scenario. If you get a disease, you get it. Not a whole lot you can do about it if you're "chosen" to get it. When I was on a ski lift in the summer, first time on a ski lift and afraid it was going to fall, etc. I eventually decided to just enjoy what was left of my life until it fell :-) So I started looking around, trying to spot deer, etc. instead of focusing so hard on what might happen in the future.