Fire blight is the most devastating bacterial disease of apples and pears world wide.
It was first discovered in North America in the mid 1800's and spread to many parts of the world since 1900. The disease was first reported in New Zealand in 1919. It has not been reported in Australia prior to 1997. The disease is caused by a bacteria, Erwinia amylovora. Accurate identification of the bacterium can be difficult and requires specialised techniques including molecular diagnosis, consequently identification may take some time.