INTERESTING FACTS ABOUT NORTH AMERICA’S ONLY MARSUPIAL, THE OPOSSUM! I hope that after reading this, you might think more affectionately about this unique animal! 1. Natural immunity. Opossums are mostly immune to rabies, and in fact, they are eight times less likely to carry rabies compared to wild dogs. 2. Poison control. Opossums have superpowers against snakes. They have partial or total immunity to the venom produced by rattlesnakes, cottonmouths and other pit vipers. 3.