Fire blight is caused by the Erwinia Amylovora bacteria. It attacks the trees of fruits with pips such as apples and pears and related ornamental and wild plants. Fire blight was introduced into Europe (Great Britain) in 1957 and can be found in nearly all European states. It was observed for the first time in Switzerland in 1989. In the German speaking cantons of St-Gall, Thurgovia and Lucerne a few orchards have already been badly affected.
In French speaking Switzerland, fire blight has also been detected but to a lesser extent, mainly in ornamental plants.
It is a quarantine disease, which must be notified to the cantonal phytosanitary service.
Fire blight is now so significant that the Agroscope ACW Wädenswil station has established a specific working group that has responsibility for popularization, forecasting, laboratory analysis and research.