Springer Andrea, Fichtel Claudia, Calvignac-Spencer Sébastien, Leendertz Fabian H, Kappeler Peter M
Behavioral Ecology and Sociobiology Unit, German Primate Center, Kellnerweg 4, 37077 Göttingen, Germany.
Project Group "Epidemiology of Highly Pathogenic Microorganisms", Robert-Koch-Institut, Seestraße 10, 13353 Berlin, Germany.
Int J Parasitol Parasites Wildl. 2015 Oct 20;4(3):385-95. doi: 10.1016/j.ijppaw.2015.10.006. eCollection 2015 Dec.
Hemoparasites can cause serious morbidity in humans and animals and often involve wildlife reservoirs. Understanding patterns of hemoparasite infections in natural populations can therefore inform about emerging disease risks, especially in the light of climate change and human disruption of natural ecosystems. We investigated the effects of host age, sex, host group size and season on infection patterns of Plasmodium sp., Babesia sp. and filarial nematodes in a population of wild Malagasy primates, Verreaux's sifakas (Propithecus verreauxi), as well as the effects of these infections on hematological variables. We tested 45 blood samples from 36 individuals and identified two species of Plasmodium, one species of Babesia and two species of filarial nematodes. Plasmodium spp. and Babesia sp. infections showed opposite patterns of age-dependency, with babesiosis being prevalent among young animals, while older animals were infected with Plasmodium sp. In addition, Babesia sp. infection was a statistically significant negative predictor of Plasmodium sp. infection. These results suggest that Plasmodium and Babesia parasites may interact within the host, either through cross-immunity or via resource competition, so that Plasmodium infections can only establish after babesiosis has resolved. We found no effects of host sex, host group size and season on hemoparasite infections. Infections showed high prevalences and did not influence hematological variables. This preliminary evidence supports the impression that the hosts and parasites considered in this study appear to be well-adapted to each other, resulting in persistent infections with low pathogenic and probably low zoonotic potential. Our results illustrate the crucial role of biodiversity in host-parasite relationships, specifically how within-host pathogen diversity may regulate the abundance of parasites.
血液寄生虫可导致人类和动物出现严重疾病，且常常涉及野生生物宿主。因此，了解自然种群中血液寄生虫感染模式有助于了解新出现的疾病风险，尤其是考虑到气候变化和人类对自然生态系统的破坏。我们调查了宿主年龄、性别、宿主群体规模和季节对野生马达加斯加灵长类动物维氏冕狐猴（Propithecus verreauxi）种群中疟原虫属、巴贝斯虫属和丝虫线虫感染模式的影响，以及这些感染对血液学变量的影响。我们检测了来自36只个体的45份血样，鉴定出两种疟原虫、一种巴贝斯虫和两种丝虫线虫。疟原虫属和巴贝斯虫属感染呈现出相反的年龄依赖性模式，巴贝斯虫病在幼龄动物中普遍存在，而老龄动物感染疟原虫属。此外，巴贝斯虫属感染是疟原虫属感染的一个具有统计学意义的负预测因子。这些结果表明，疟原虫和巴贝斯虫寄生虫可能在宿主体内相互作用，要么通过交叉免疫，要么通过资源竞争，因此疟原虫感染只能在巴贝斯虫病消退后才会发生。我们发现宿主性别、宿主群体规模和季节对血液寄生虫感染没有影响。感染的发生率很高，且不影响血液学变量。这一初步证据支持了这样一种观点，即本研究中所考虑的宿主和寄生虫似乎彼此适应良好，导致持续感染，致病性低，人畜共患病潜力可能也低。我们的结果说明了生物多样性在宿主 - 寄生虫关系中的关键作用，特别是宿主体内病原体多样性如何调节寄生虫的丰度。
