Kim Younjung, Métras Raphaëlle
Sorbonne Université, INSERM, Institut Pierre Louis d'Épidémiologie et de Santé Publique (IPLESP) Paris France.
Ecol Evol. 2025 Apr 23;15(4):e71128. doi: 10.1002/ece3.71128. eCollection 2025 Apr.
, a tick vector of the severe fever with thrombocytopenia syndrome (SFTS) virus, has long been established in parts of East Asia and Oceania but is now rapidly expanding in the eastern US, raising significant concerns about its further domestic and international spread. In this study, we mapped the spatial expansion risk of in North America and Europe by training a habitat suitability model with its occurrence data from East Asia and Oceania. Our model incorporated ecologically relevant predictors for tick survival, which have been neglected in previous habitat suitability modeling for this species. Specifically, we employed temperature, relative humidity, saturation deficit, precipitation, and vegetation level as predictors, with the first three distinguishing between tick questing and non-questing seasons to account for their varying impacts on tick survival during periods of activity and dormancy. The best-fitting model included seasonal saturation deficit and temperature as predictors along with vegetation, with the threshold values of saturation deficit and temperature for suitability closely aligning with existing literature. Spatial projections based on the best-fitting model most closely delineated the current boundaries of occurrences in the eastern US. In contrast, for the western US, where no has been detected yet, the model predicted only a few isolated coastal areas as suitable. This finding contrasts with earlier studies, which projected extensive suitable areas along the coast and extending inland. In Europe, the model also identified limited suitability, mainly confined to coastal areas of southern Europe. In conclusion, by incorporating meteorological predictors that account for seasonal tick activity, our findings reshape the understanding of spatial expansion risk in western North America and Europe, underscoring the need for refined and targeted surveillance strategies.
作为严重发热伴血小板减少综合征（SFTS）病毒的蜱虫媒介，长期以来在东亚和大洋洲部分地区存在，但目前正在美国东部迅速扩张，引发了对其在国内和国际进一步传播的重大担忧。在本研究中，我们通过利用来自东亚和大洋洲的分布数据训练栖息地适宜性模型，绘制了其在北美和欧洲的空间扩张风险图。我们的模型纳入了与蜱虫生存相关的生态预测因子，而这些因子在该物种先前的栖息地适宜性建模中被忽视了。具体而言，我们采用温度、相对湿度、饱和差、降水量和植被水平作为预测因子，前三个因子用于区分蜱虫的搜寻季节和非搜寻季节，以说明它们在活动期和休眠期对蜱虫生存的不同影响。最佳拟合模型包括季节性饱和差、温度以及植被作为预测因子，饱和差和温度的适宜性阈值与现有文献密切吻合。基于最佳拟合模型的空间预测最准确地描绘了美国东部目前的分布边界。相比之下，在美国西部尚未检测到该蜱虫的地区，模型仅预测了少数几个孤立的沿海地区适宜其生存。这一发现与早期研究不同，早期研究预测沿海地区及内陆有广泛的适宜区域。在欧洲，该模型也确定适宜区域有限，主要局限于南欧沿海地区。总之，通过纳入考虑蜱虫季节性活动的气象预测因子，我们的研究结果重塑了对北美西部和欧洲该蜱虫空间扩张风险的认识，强调了制定精确且有针对性的监测策略的必要性。
