Department of Entomology, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA.
Illinois Natural History Survey, University of Illinois Urbana-Champaign, Champaign, IL 61820, USA.
J Med Entomol. 2022 Sep 14;59(5):1625-1635. doi: 10.1093/jme/tjac091.
In the United States, the Gulf Coast tick (Amblyomma maculatum Koch) is a species of growing medical and veterinary significance, serving as the primary vector of the pathogenic bacterium, Rickettsia parkeri (Rickettsiales: Rickettsiaceae), in humans and the apicomplexan parasite, Hepatozoon americanum, in canines. Ongoing reports of A. maculatum from locations outside its historically reported distribution in the southeastern United States suggest the possibility of current and continuing range expansion. Using an ecological niche modeling approach, we combined new occurrence records with high-resolution climate and land cover data to investigate environmental drivers of the current distribution of A. maculatum in the United States. We found that environmental suitability for A. maculatum varied regionally and was primarily driven by climatic factors such as annual temperature variation and seasonality of precipitation. We also found that presence of A. maculatum was associated with open habitat with minimal canopy cover. Our model predicts large areas beyond the current distribution of A. maculatum to be environmentally suitable, suggesting the possibility of future northward and westward range expansion. These predictions of environmental suitability may be used to identify areas at potential risk for establishment and to guide future surveillance of A. maculatum in the United States.
在美国，海湾岸蜱（Amblyomma maculatum Koch）是一种具有日益重要的医学和兽医意义的物种，它是人类病原体帕克立克次体（Rickettsiales：Rickettsiaceae）和犬类中顶复门寄生虫赫氏巴贝斯虫（Hepatozoon americanum）的主要传播媒介。不断有报道称，海湾岸蜱出现在其历史分布范围之外的美国东南部以外的地区，这表明其当前和持续的分布范围可能正在扩大。本研究采用生态位模型方法，将新的出现记录与高分辨率气候和土地覆盖数据相结合，以研究美国海湾岸蜱当前分布的环境驱动因素。研究发现，海湾岸蜱的环境适宜性存在区域差异，主要受气候因素影响，如年温差和降水季节性。研究还发现，海湾岸蜱的存在与最小冠层覆盖的开阔生境有关。我们的模型预测，目前海湾岸蜱分布范围之外的大片区域在环境上是适宜的，这表明未来可能会向北和向西扩展其分布范围。这些环境适宜性的预测结果可用于识别可能有建立种群风险的区域，并指导未来在美国对海湾岸蜱的监测。
