I know that I'm guilty in the past for Kissing fish after capture, and even tried before netting them (different story), but I carry an Antibacterial Gel I got from a Builders Equipment Supplier, to try to reduce the risks. Comes in handy for a couple of reasons. Working as a Store Detective, some of the scroats who we stopped were filthy (and I mean Disgusting), and it does also Kill the Weils disease bacteria.

All food is bagged and Pans etc are never left out out.
I've even got to the stage that my Baccy and Ciggie Papers are kept in the pocket of my combats rather than being left on my Tackle Box

I know that if I do ever get a Flu or Bad Cold I go straight to my Doctors or Local Emergency Clinic and explain the risks of Leptospirosis. Just about the first thing they always do is stick you on a 10 day course of Antibiotics, as opposed to the usual 7day and give you strict warnings that if any symptoms become worse to get back there or to A&E. Thank Goodness I have only ever had to go to A&E once when the flu progressed to a severe Headache. The nurses weren't too happy as they thought I was pulling a fast one, but once explained and they checked in the Big Black Book in the Nurses station were damn happy to keep me in for a nights observation.

Weils disease can be spread by many other rodents and animals, not just Rats.