Biological Station Rybachy of the Zoological Institute, Russian Academy of Sciences, Kaliningrad Region, 238535, Rybachy, Russia.
Nature Research Centre, Akademijos 2, LT-09412, Vilnius 21, Lithuania.
Malar J. 2021 Feb 10;20(1):82. doi: 10.1186/s12936-021-03588-3.
Avian malaria parasites are microorganisms parasitizing erythrocytes and various tissues of the birds; they are common and distributed worldwide. These parasites are known to infect birds of different taxa and be the cause of the deaths of birds in the wild and in captivity. The species of parasites with the ability to colonize new territories and infect local non-migratory birds are of particular interest. This scenario is likely in temperate zones of Europe, because of climate change and its contribution in spreading vectors of southern origin, which can be involved in the transmission of malaria parasites. In the present study, a tropical Plasmodium parasite from a naturally infected long-distance migrant bird was isolated and tested for its ability to develop in common species of mosquitoes and European short-distance migrant birds.
Plasmodium sp. (pFANTAIL01) was isolated on the Curonian spit of the Baltic sea coast from the naturally infected Common rosefinch, Carpodacus erythrinus in June 2019. The parasite was described based on the morphological features of its blood stages, the partial mitochondrial cytochrome b gene and development after experimental infection of birds and mosquitoes. The parasite was inoculated into Eurasian siskins, Carduelis spinus. Parasitaemia, haematocrit and weight of birds were monitored. At the end of the survey, internal organs were collected to study exoerythrocytic stages of this parasite. Experimental infection of mosquitoes Culex pipiens form molestus and Culex quinquefasciatus was applied to study sporogonic development of the parasite.
Based on morphological features, the parasite was described as a new species, Plasmodium collidatum n. sp., and attributed to subgenus Novyella. It was revealed that the obtained pFANTAIL01 lineage is a generalist parasite infecting a wide range of avian hosts and most likely is transmitted in South and Southeast (SE) Asia and Oceania. In Europe, this strain was recorded only in adult migratory birds wintering in South Asia. This parasite developed high parasitaemia in experimentally infected siskins and caused 25 % mortality. Exoerythrocytic stages of pFANTAIL01 were found in the lungs, liver, spleen and kidney of the deceased birds. Sporogonic development did not occur in Cx. pipiens form molestus and Cx. quinquefasciatus mosquitoes.
Plasmodium collidatum is a highly virulent for Eurasian siskin and completes its development in these birds, which can be considered as a potential vertebrate host if the transmission of the infection starts occurring in Europe and temperate zones.
禽疟原虫是一种寄生在鸟类红细胞和各种组织中的微生物，广泛分布于世界各地。这些寄生虫已知会感染不同分类群的鸟类，并导致野生和圈养鸟类死亡。能够在新领地定殖并感染当地非迁徙鸟类的寄生虫物种尤其令人关注。这种情况在欧洲的温带地区很可能发生，因为气候变化及其对南方起源的传播媒介的贡献，这些媒介可能参与疟原虫的传播。在本研究中，从自然感染的长途迁徙候鸟身上分离出一种热带疟原虫，并测试其在常见的蚊子和欧洲短程迁徙鸟类中发育的能力。
2019 年 6 月，从波罗的海沿岸库尔斯沙嘴的自然感染的普通朱雀（ Carpodacus erythrinus ）中分离出疟原虫（ pFANTAIL01 ）。该寄生虫是根据其血液阶段的形态特征、部分线粒体细胞色素 b 基因和对鸟类和蚊子的实验感染后的发育情况来描述的。将寄生虫接种到欧亚红额丝雀（ Carduelis spinus ）中。监测鸟类的寄生虫血症、血细胞比容和体重。在调查结束时，收集内脏器官以研究该寄生虫的外红细胞期。应用实验感染致倦库蚊（ Culex pipiens form molestus ）和三带喙库蚊（ Culex quinquefasciatus ）来研究寄生虫的孢子生殖发育。
根据形态特征，该寄生虫被描述为一个新物种，即 Collidatum 疟原虫（ Plasmodium collidatum ）n. sp.，并归属于 Novyella 亚属。研究表明，获得的 pFANTAIL01 谱系是一种寄生虫，可感染广泛的鸟类宿主，可能在南亚和东南亚（SE）和大洋洲传播。在欧洲，这种菌株仅在冬季在南亚的迁徙候鸟中被记录。该寄生虫在实验感染的欧亚红额丝雀中引起高寄生虫血症，并导致 25%的死亡率。在死亡鸟类的肺、肝、脾和肾中发现了 pFANTAIL01 的外红细胞期。致倦库蚊和三带喙库蚊中未发生孢子生殖发育。
Collidatum 疟原虫对欧亚红额丝雀具有高度毒力，并在这些鸟类中完成发育，如果这种感染的传播开始在欧洲和温带地区发生，这些鸟类可以被视为潜在的脊椎动物宿主。
