Pest risk analysis - organisms or pathways?

Pest risk analysis is central to determining both country risks from potential biotic threats and identifying the nature and scale of measures the country puts in place to address the identified threat. International Plant Protection Convention procedures, described in International Standards for Phytosanitary Measures No. 11, are the basis for pest risk analysis and recognise three elements; initiation, pest risk assessment and pest risk management. Among the components of the initiation phase, the decision on whether to base the pest risk analysis on a pest or a pathway for movement of a pest is fundamental. However, it must be recognised that the two are inextricably linked, although the tendency to concentrate on the pest is dominant. A pest-based approach has the advantage of focus on a named organism but, increasingly, there is recognition that other pest organisms that might be associated with the same pathway will tend to be missed. Such a ‘list-based ’ approach has been valuable in raising awareness and in tackling recognised threats, but it is probably true to state that most pest-based pest risk analyses have been retrospective and only initiated when a pest has actually been found in a new geographic area. It is, therefore, important to recognise that a range of organisms in addition to those on a phytosanitary list can move along a given pathway. This suggests the need for a more generic approach to risk mitigation of high-risk pathways so that organisms not on current phytosanitary lists are accounted for. In this context, live plants for planting pose the greatest threats and the greatest challenge in development of effective phytosanitary measures. In