Rabbits can be eaten safely any time of year, disposable rubber gloves are recommended for cleaning and don't eat any of the organs. The R month adage works pretty well along the northern Rockies, but in eastern WA we don't get frost until October or even later some years. Unfortunately, while the flea density does decrease later in the year/winter, that is more for plague, which is not often an issue in WA. A white-spotted liver or spleen should cause one to suspect an advanced case of tularemia, however, it can also be acquired from normal appearing asymptomatic animals.
There is almost nothing transmissible disease-wise to humans from upland game birds and big game species, however with other species - especially carnivores, rodents and bunnies - meat should be thoroughly cooked and blood borne pathogen sanitary protocols followed to prevent disease and parasite transmission. That means handling with gloves only until on the cooker.