Yup, raccoons faeces can spread several problems: Bayliscaris and other roundworms, Leptospira and some viruses. Airborne spreading rabies from faeces is very rare, but some cases were reported with bats in caves, so should be also a veeeery small probability with raccoons.

Droppings from crows and other birds can spread Parrot fever on the other hand.

Sun rays eliminate several of those problems, like Leptospira. Droppings in the garden should be more "clean" than in your attic.