Armadillos carry several things of note:

• They carry bacteria that can cause Hansen's disease (leprosy). Some armadillos in the southern United States naturally harbor the Mycobacterium leprae bacteria, which causes leprosy. Humans can acquire leprosy from handling armadillos or consuming their meat. Around 15-20% of armadillos in some areas like Florida carry this bacteria. The nine-banded armadillo is one known carrier.

• They can carry other diseases such as leptospirosis, salmonella, histoplasmosis, rabies (rarely), and tapeworms. These diseases can be transmitted primarily through contact with armadillo feces or their environment.

• Armadillos also carry insects, grubs, and other invertebrates in their diet, and use their claws for digging these from the soil, as well as for digging burrows.

So primarily, from a human concern perspective, the key "carrier" aspect is that armadillos can carry and transmit leprosy bacteria as well as other pathogens.