Taxonomic, geographic, and diversity trends for exotic plant pests in recent biosurveillance articles

Some plant protection organizations use biosurveillance to identify heightened risks from exotic plant pests or generally inform safeguarding. Biosurveillance programs typically focus on individual species but accumulate useful trend data over time. We extracted information from 1,612 articles from PestLens, which has collected open-source reports about plant pests exotic to the USA since 2007. The extracted information included scientific name, pest type (nine categories), and reporting country. We analyzed the data to identify trends and evaluate the diversity of pest reports. An average month had 12.4 total articles, with six on insects, two on fungi, and one each on bacteria, nematodes, plants, and viruses. Insects made up 45 percent of all articles, followed by fungi at 19 percent. Fifty-four percent of articles referenced Asian (31.2 percent) and European (23.2) countries, followed by North America (16.3, but this diminished over time). Regional reporting varied substantially over time, but Asian articles particularly increased over time. The mean annual number of unique genera reported increased over time, while mean annual articles per genus decreased. Thus, rather than some problematic pests being repeatedly mentioned, more novel pests were being reported upon over time. We identified high reporting periods for some pests and tested count-based formulas derived from those patterns on the entire dataset. Applying these formulas at periodic intervals (e.g., quarterly) might help identify less obvious threats. Although often looked at on a case-by-case basis, collected biosurveillance data had significant potential to be used periodically for trend analysis and assessment.