Kollars T M
Institute of Arthropodology and Parasitology, Georgia Southern University, Statesboro 30460, USA.
J Parasitol. 1996 Oct;82(5):707-10.
Fourteen species of small mammals were captured from July 1990 through August 1991 in Tennessee, from which 1,217 immature Dermacentor variabilis and 1 Ixodes dentatus were collected. Mammal species were given scores of importance (TS) as hosts to immature D. variabilis based on mean intensity and prevalence. The rice rat ranked the highest, with a TS = 5, followed by the golden mouse TS = 4, white-footed mouse TS = 3, pine vole TS = 2, cotton rat TS = 1, with the Norway rat, house mouse, and short-tailed shrew all having a TS = 0. Assigning a TS allows a quantitative method for differentiating and ranking small mammals as hosts for immature D. variabilis. Relative abundance of a species can also be important in determining D. variabilis populations, even with a low TS. The potential of Rocky Mountain spotted fever (RMSFP) to occur in an area was estimated using the total score of small mammal hosts in an area and multiplying the relative abundance of important host species. The RMSFP of a site, based only upon small mammal species composition and relative abundance of important host species, was an accurate estimate of adult D. variabilis infesting raccoons and opossums at that trap site (P < or = 0.001). A RMSFP of 1.61 is needed to produce an estimated 252 adults per ha (RMSF threshold) at 98% survival of engorged immature ticks (P < 0.001).
1990年7月至1991年8月期间，在田纳西州捕获了14种小型哺乳动物，从中收集到1217只未成熟的变异革蜱和1只齿突硬蜱。根据平均感染强度和感染率，将哺乳动物物种作为未成熟变异革蜱宿主的重要性给予评分（TS）。稻鼠得分最高，TS = 5，其次是金仓鼠TS = 4，白足鼠TS = 3，松田鼠TS = 2，棉鼠TS = 1，而褐家鼠、小家鼠和短尾鼩的TS均为0。赋予TS值提供了一种定量方法，用于区分小型哺乳动物并将其作为未成熟变异革蜱宿主进行排名。即使TS值较低，物种的相对丰度在确定变异革蜱种群数量方面也可能很重要。利用某一地区小型哺乳动物宿主的总分并乘以重要宿主物种的相对丰度，来估计落基山斑疹热（RMSFP）在该地区发生的可能性。仅基于小型哺乳动物物种组成和重要宿主物种的相对丰度，某一地点的RMSFP是对该诱捕地点感染浣熊和负鼠的成年变异革蜱数量的准确估计（P≤0.001）。要在饱血未成熟蜱98%存活的情况下，每公顷产生估计252只成年蜱（RMSF阈值），需要RMSFP为1.61（P < 0.001）。
