Karbowiak Grzegorz, Biernat Beata, Szewczyk Tomasz, Sytykiewicz Hubert
Witold Stefański Institute of Parasitology, Polish Academy of Sciences, Twarda 51/55, 00-818 Warszawa, Poland.
Department of Tropical Parasitology, Institute of Maritime and Tropical Medicine, Medical University of Gdańsk, Powstania Styczniowego 9B, 81-519 Gdynia, Poland.
Ann Parasitol. 2015;61(4):221-8. doi: 10.17420/ap6104.11.
Tick-borne pathogens are common in the natural environment, but their occurrence has a focal character. They occur in the natural environment in the form of the enzootic sources of infection. The general components include the animal reservoir, amplifiers and the efficient vector. However, the particular role of components can differ depending on the pathogen, the host range and possible transmission routes. Animal reservoir of pathogen are vertebrate animals, being the hosts of pathogens. In Europe these are small or medium-sized mammals and sometimes birds that feed on the ground. The competence of an animal reservoir is determined by the ability to communicate the infection; long-term persistence of the pathogen in the host; long-duration of infectivity of the animal for ticks; a sufficient number of animals in the endemic region. Amplifiers for ticks are artiodactyls. They are hosts for nymphs and adult ticks, thereby making it possible for ticks to propagate and maintain the proper size of their population. Efficient vector for pathogen are ticks. The first characteristic feature of efficient vectors is feeding duration exceeding 24 hours; the high density of the tick population. The conditions necessary to consider ticks as efficient vectors are met in Central Europe by the Ixodes ricinus, Dermacentor reticulatus and D. marginatus ticks. There are the general differences in biology between Ixodes persulcatus complex ticks and Dermacentor ticks, affecting their different role and ability in pathogens spreading - the range of hosts; the ability to inhabiting of various environments and resistance to unfavourable conditions; the duration of larvae and nymphs activity. The combination of tick's biology, pathogen ability to transmission, and mammal hosts' competence, determines the particular role of larvae, nymphs and adults in pathogen circulation in the natural environment, as well as transmission to new hosts.
蜱传病原体在自然环境中很常见，但其发生具有局部性特征。它们以动物源性感染源的形式存在于自然环境中。一般组成部分包括动物宿主、扩增宿主和有效传播媒介。然而，各组成部分的具体作用可能因病原体、宿主范围和可能的传播途径而异。病原体的动物宿主是脊椎动物，即病原体的宿主。在欧洲，这些是中小型哺乳动物，有时也包括在地面觅食的鸟类。动物宿主的感染能力取决于传播感染的能力；病原体在宿主体内的长期持续存在；动物对蜱的感染性持续时间；流行地区有足够数量的动物。蜱的扩增宿主是偶蹄目动物。它们是若虫和成年蜱的宿主，从而使蜱得以繁殖并维持其种群的适当规模。病原体的有效传播媒介是蜱。有效传播媒介的第一个特征是取食时间超过24小时；蜱种群密度高。在中欧，蓖麻硬蜱、网纹革蜱和边缘革蜱满足将蜱视为有效传播媒介所需的条件。全沟硬蜱复合体蜱和革蜱在生物学上存在一般差异，这影响了它们在病原体传播中的不同作用和能力——宿主范围；栖息于各种环境的能力和对不利条件的抵抗力；幼虫和若虫的活动持续时间。蜱的生物学特性、病原体的传播能力以及哺乳动物宿主的感染能力相结合，决定了幼虫、若虫和成虫在自然环境中病原体传播以及向新宿主传播中的具体作用。
