Post-hurricane Analysis of Citrus Canker Spread and Progress towards the Development of a Predictive Model to Estimate Disease Spread Due to Catastrophic Weather Events

Many factors have been involved in the spread of citrus canker (Xanthomonas axonopodis pv. citri); however, the 2004 hurricane season appears to have been one of the major factors leading to the widespread and numerous citrus canker infections discovered in late 2004 and 2005. Geospatially referenced citrus canker infection data from infections that were discovered after the 2004 hurricanes were examined in relation to wind and rain conditions experienced during the hurricanes and used to develop a predictive model to explain storm-related spread of citrus canker. The model incorporates a “threshold” concept for wind and rains that, in-effect, incorporates only biologically significant weather parameters in the calculations. When applied to three distinct areas of the state, the predictive model accounted for approximately 80% of the hurricane related and subsequent secondary spread of citrus canker over the next 14 months. Therefore, the use of the predictive model shows great promise a tool to predict disease spread as a result of extreme weather events and as a means of targeting resources for citrus canker survey and detection activities. Accepted for publication 11 May 2006. Published 22 August 2006.