Emerging or re-emerging bacterial zoonotic diseases: bartonellosis, leptospirosis, Lyme borreliosis, plague.

There are a whole series of emerging and re-emerging zoonotic diseases present in the Northern Hemisphere and the author describes four of them, namely, bartonellosis, leptospirosis, Lyme borreliosis and plague. Reasons for the emergence or re-emergence of such diseases are not clear, but factors such as human demographics, economic development and land use, international travel and commerce, and microbial adaptation, are thought to be involved. Control of emerging and re-emerging diseases has become a major challenge for the international community and it is important to disseminate information about diagnosis and control capabilities, particularly to people working in public health.