In this paper, the authors describe a new method for assessing the impact of emerging infections on global trade flows. When one compares notifications to the World Trade Organization (WTO) of the emergency measures taken to control certain animal and plant diseases with the trade values of certain products from the United Nation's Commodity Trade Statistics Database (Comtrade) (identified through the World Customs Organization's harmonised system of tariff product codes [HS]), it is possible to estimate the extent to which trade has been diverted from the affected economies. The authors study in detail the example of bovine spongiform encephalopathy (BSE). When member countries of the WTO change their import policies towards the goods of a trading partner, as the result of an emerging disease such as BSE, they must file notifications of such changes through the Sanitary and Phytosanitary Committee of the WTO. To quantify the impact of BSE on trade, the authors compared these notifications against Comtrade statistics, using the HS 1996 tariff code variable. (The HS 1996 tariff codes allow the tracking and recording of the volumes of exports and imports, in quantity and value, between any two member countries between 1998 and 2000 in the database.) The authors then used this linked dataset to describe the dollar impact of the BSE-related notifications filed in 2000 on the trade flow of imports. The results of this study suggest that economies affected by BSE notifications saw a decline of US$5.6 billion from hypothetical projections in designated products. At the same time, unaffected economies saw an increase of US$1.5 billion from hypothetical projections in the same products. Thus, it may be concluded that import restrictions to control the spread of emergent spongiform encephalopathy infection had a significant effect on trade flows. These results also emphasise the interconnectedness of global trade: trade restrictions for some economies may enhance trade opportunities for others. Further studies using these methods are warranted.