Interesting article discusses many of the diseases that cross from animal to human populations--and vice versa. Thanks to Lori for the tip.
Origins of new diseases: Zoonotic pandemics come from bats, birds, monkeys, cows, and other animals. - Slate Magazine:
"Humans can also spread our own native microbes to other species. Recent studies have shown that humans have spread antibiotic-resistant strains of Staphylococcus aureus to many different species, including domestic chickens, pigs, and even chimpanzees and dolphins. We, too, are a walking biohazard."