University of Pennsylvania, Biology Department, 433 S University Ave, 301 Leidy Labs, Philadelphia, PA 19104, USA.
New York State Department of Health, Bureau of Communicable Disease Control, Empire State Plaza, Corning Tower Building, Room 651, P.O. Box 509, Albany, NY 12201-0509, USA.
Int J Parasitol. 2021 Mar;51(4):311-320. doi: 10.1016/j.ijpara.2020.10.002. Epub 2020 Dec 24.
Many species have experienced dramatic changes in both geographic range and population sizes in recent history. Increases in the geographic range or population size of disease vectors have public health relevance as these increases often precipitate the emergence of infectious diseases in human populations. Accurately identifying environmental factors affecting the biogeographic patterns of vector species is a long-standing analytical challenge, stemming from a paucity of data capturing periods of rapid changes in vector demographics. We systematically investigated the occurrence and abundance of nymphal Ixodes scapularis ticks at 532 sampling locations throughout New York State (NY), USA, between 2008 and 2018, a time frame that encompasses the emergence of diseases vectored by these ticks. Analyses of these field-collected data demonstrated a range expansion into northern and western NY during the last decade. Nymphal abundances increased in newly colonised areas, while remaining stable in areas with long-standing populations over the last decade. These trends in the geographic range and abundance of nymphs correspond to both the geographic expansion of human Lyme disease cases and increases in incidence rates. Analytic models fitted to these data incorporating time, space, and environmental factors, accurately identified drivers of the observed changes in nymphal occurrence and abundance. These models accounted for the spatial and temporal variation in the occurrence and abundance of nymphs and can accurately predict nymphal population patterns in future years. Forecasting disease risk at fine spatial scales prior to the transmission season can influence both public health mitigation strategies and individual behaviours, potentially impacting tick-borne disease risk and subsequently human disease incidence.
许多物种在最近的历史中经历了地理范围和种群规模的剧烈变化。病媒生物地理范围或种群规模的增加与公共卫生有关，因为这些增加通常会引发人类群体中的传染病。准确识别影响病媒生物生物地理模式的环境因素是一个长期存在的分析挑战，这源于缺乏捕捉病媒生物人口快速变化时期的数据。我们系统地调查了 2008 年至 2018 年期间美国纽约州（NY）532 个采样点的幼虫硬蜱（Ixodes scapularis）的发生和丰度，这段时间涵盖了这些蜱传播疾病的出现。对这些实地采集数据的分析表明，在过去十年中，硬蜱向北和向西扩展到了 NY 的北部和西部。在新殖民地区，幼虫丰度增加，而在过去十年中人口长期稳定的地区则保持稳定。幼虫地理范围和丰度的这些趋势与人类莱姆病病例的地理扩张以及发病率的增加相对应。将时间、空间和环境因素纳入这些数据的分析模型准确地确定了观察到的幼虫发生和丰度变化的驱动因素。这些模型解释了幼虫发生和丰度的空间和时间变化，并能准确预测未来几年幼虫的种群模式。在传播季节之前，在精细的空间尺度上预测疾病风险可以影响公共卫生缓解策略和个人行为，从而潜在地影响蜱传疾病风险和随后的人类疾病发病率。
