Tularemia is a bacteria spread via flea and tick bites. It is supposedly generally fatal to rabbits within 8-14 days. This means that if you have low temperatures for two weeks, any live bunnies should be uninfected, as any rabbits infected before the freeze will be deceased and the freeze inhibits the spread from animal to animal.
To prevent exposure, wear bug spray when in the woods to inhibit transfer from parasites. Wear gloves when handling game in order to prevent direct contamination from infected bunnies. Infected animals may (rarely) have open sores, white spots on the liver are also indicative of tularemia infection.
If thoroughly cooked, tularemia bacteria will be killed. Signs in humans show up within 3-5 days, and it can be treated with antibiotics. Signs in humans include sores on the skin, fever, lethargy, etc.
I used to go bunny hunting with a biologist, which is why I remember most of this stuff. The wikipedia page on Tularemia is fairly comprehensive.