Tilletia indica, the fungus that causes Karnal bunt of wheat, is listed as a I/AI quarantine pest for the European Union (EU) (Anon., 2000a). This means that it is considered absent from the EU, is potentially damaging and so its entry into the EU is banned. This listing was the result of a Pest Risk Analysis (PRA) (Sansford, 1996, 1998), which considered the potential for the pathogen to enter, establish and cause unacceptable impacts in the UK/EU following the first reports of the disease in the USA in 1996 (Ykema et al., 1996). This PRA was updated in 2004 (Sansford, 2004) and recently fully revised (Sansford et al., 2006) for the EU. This new EU-PRA continues to support the view that 

 T. indica  has the potential to enter, establish and cause unacceptable economic impacts throughout much of the wheat-growing area of the EU.

Two recent papers (Jones, 2007a,b) have challenged these tenets and the new EU-PRA.

In this letter, we summarise the work of a 4-year collaborative study and address the key points made by Jones (2007a,b) and refute his conclusions, particularly regarding (i) past opportunities for entry to Europe; (ii) the climatic requirements for the completion of the lifecycle of T. indica, leading to the disease Karnal bunt; (iii) inoculum thresholds; (iv) the potential economic damage caused by the disease in Europe; and (v) the cost of control. The full findings of the study can be accessed online (http://karnalpublic.pestrisk.net/) together with published accounts of teliospore survival and germination in Europe (Inman et al., 2008) and susceptibility of European wheat cultivars to T. indica  (Riccioni et al., 2008).