Nature Research Centre, Akademijos 2, LT-08412, Lithuania.
Nature Research Centre, Akademijos 2, LT-08412, Lithuania; Biological Station Rybachy of Zoological Institute RAS, Rybachy 238535, Russian Federation.
Acta Trop. 2022 Feb;226:106247. doi: 10.1016/j.actatropica.2021.106247. Epub 2021 Nov 18.
Although co-infections and interactions of parasites are a very common phenomenon in the wild, information received from studies on avian Plasmodium spp. is scarce and fragmented due to its complex nature. Different interactions of parasites and domination of one parasite may have a detrimental effect on transmission success of another pathogen. Untangling these interactions and competitive behavior of malarial parasites may help understanding why some haemosporidian parasites are dominant in certain host species, while others are observed only occasionally. We investigated the development of Plasmodium relictum (genetic lineage GRW4) during single and co-infection with a closely related lineage SGS1, with the aim to determine whether co-infections affect parasite development and condition of experimentally infected Eurasian siskins (Spinus spinus). For the experimental study of these two closely related lineages, a new qPCR protocol was designed to accurately quantify the parasitemia, i.e. the amount of infected red blood cells, during the blood stages of each of the lineages. Our results show that during co-infection, GRW4 parasitemia was transient and disappeared from peripheral blood during acute increases of SGS1. Health parameters of infected birds did not differ between the GRW4 single infected group and the co-infection group. GRW4 induced infection was outcompeted and suppressed by the presence of the lineage SGS1, which is broadly transmitted in Northern Europe. This suggests that double infections and dominating lineages in the area may influence the transmission success of some avian Plasmodium parasites.
虽然寄生虫的合并感染和相互作用在野外是一种非常普遍的现象，但由于其复杂性，从鸟类疟原虫 spp. 的研究中获得的信息是稀缺和零散的。寄生虫的不同相互作用和一种寄生虫的优势可能对另一种病原体的传播成功产生不利影响。理清这些相互作用和疟原虫的竞争行为可能有助于理解为什么一些血孢子虫寄生虫在某些宿主物种中占优势，而其他寄生虫则很少观察到。我们研究了单感染和与密切相关的 SGS1 谱系共同感染时的 Plasmodium relictum（遗传谱系 GRW4）的发展，目的是确定合并感染是否会影响寄生虫的发育和实验感染的欧亚山雀（Spinus spinus）的状况。为了对这两个密切相关的谱系进行实验研究，设计了一种新的 qPCR 方案来准确量化每个谱系的血液阶段中的寄生虫血症，即受感染的红细胞数量。我们的结果表明，在共同感染期间，GRW4 的寄生虫血症是短暂的，并且在 SGS1 的急性增加期间从外周血液中消失。感染鸟类的健康参数在 GRW4 单一感染组和共同感染组之间没有差异。GRW4 诱导的感染被广泛传播于北欧的 SGS1 谱系所竞争和抑制。这表明该地区的双重感染和优势谱系可能会影响一些鸟类疟原虫寄生虫的传播成功。
