[Epona]

It's never really been eradicated, it's endemic (ie. prevalent) in all parts of the world except Europe and Antarctica. Another epidemic is expected by the medical community.

Can be spread by coughing, sneezing, and even talking can shower someone with the Yersinia Pestis bacteria by an infected person, but this only occurs in the most serious cases. Symptoms: Swollen lymph nodes, high fever, delerium. As it's a bacteria it can be treated very effectively with antibiotics.

It also survives as spores in the ground for centuries. If they are inhaled they can cause the disease. Archaeologists excavating 16th and 17th century plague pits in Britain wear masks so they don't breath it in.