Institut Pasteur de Madagascar, Antananarivo 101, BP 1274, Ambatofotsikely, Madagascar.
Faculté des Sciences, Université d'Antananarivo, BP 706, Antananarivo 101, Antananarivo, Madagascar.
Malar J. 2021 Mar 20;20(1):157. doi: 10.1186/s12936-021-03696-0.
Numerous studies have been undertaken to advance knowledge of apicomplexan parasites infecting vertebrates, including humans. Of these parasites, the genus Plasmodium has been most extensively studied because of the socio-economic and public health impacts of malaria. In non-human vertebrates, studies on malaria or malaria-like parasite groups have been conducted but information is far from complete. In Madagascar, recent studies on bat blood parasites indicate that three chiropteran families (Miniopteridae, Rhinonycteridae, and Vespertilionidae) are infected by the genus Polychromophilus with pronounced host specificity: Miniopterus spp. (Miniopteridae) harbour Polychromophilus melanipherus and Myotis goudoti (Vespertilionidae) is infected by Polychromophilus murinus. However, most of the individuals analysed in previous studies were sampled on the western and central portions of the island. The aims of this study are (1) to add new information on bat blood parasites in eastern Madagascar, and (2) to highlight biotic and abiotic variables driving prevalence across the island.
Fieldworks were undertaken from 2014 to 2016 in four sites in the eastern portion of Madagascar to capture bats and collect biological samples. Morphological and molecular techniques were used to identify the presence of haemosporidian parasites. Further, a MaxEnt modelling was undertaken using data from Polychromophilus melanipherus to identify variables influencing the presence of this parasite RESULTS: In total, 222 individual bats belonging to 17 species and seven families were analysed. Polychromophilus infections were identified in two families: Miniopteridae and Vespertilionidae. Molecular data showed that Polychromophilus spp. parasitizing Malagasy bats form a monophyletic group composed of three distinct clades displaying marked host specificity. In addition to P. melanipherus and P. murinus, hosted by Miniopterus spp. and Myotis goudoti, respectively, a novel Polychromophilus lineage was identified from a single individual of Scotophilus robustus. Based on the present study and the literature, different biotic and abiotic factors are shown to influence Polychromophilus infection in bats, which are correlated based on MaxEnt modelling.
The present study improves current knowledge on Polychromophilus blood parasites infecting Malagasy bats and confirms the existence of a novel Polychromophilus lineage in Scotophilus bats. Additional studies are needed to obtain additional material of this novel lineage to resolve its taxonomic relationship with known members of the genus. Further, the transmission mode of Polychromophilus in bats as well as its potential effect on bat populations should be investigated to complement the results provided by MaxEnt modelling and eventually provide a comprehensive picture of the biology of host-parasite interactions.
为了增进对感染脊椎动物（包括人类）的顶复门寄生虫的了解，已经开展了许多研究。在这些寄生虫中，疟原虫属的研究最为广泛，因为疟疾对社会经济和公共卫生造成了影响。在非人类脊椎动物中，已经开展了关于疟疾或类似疟疾寄生虫群的研究，但信息远不完整。在马达加斯加，最近对蝙蝠血液寄生虫的研究表明，有三个蝙蝠科（长翼蝠科、蹄蝠科和蝙蝠科）被变色嗜人菌属感染，宿主特异性明显：长翼蝠科的微型蝠属（Miniopteridae）携带变色嗜人菌属黑色素体和毛腿蝠属（Myotis goudoti）（蝙蝠科）被变色嗜人菌属鼠耳蝠属感染。然而，以前的研究中分析的大多数个体都是在岛屿的西部和中部采集的。本研究的目的是：（1）增加马达加斯加东部蝙蝠血液寄生虫的新信息；（2）突出驱动整个岛屿寄生虫流行的生物和非生物变量。
从 2014 年至 2016 年，在马达加斯加东部的四个地点进行实地调查，以捕获蝙蝠并收集生物样本。使用形态学和分子技术来确定血孢子虫寄生虫的存在。此外，使用变色嗜人菌属黑色素体的数据进行了最大熵建模，以确定影响这种寄生虫存在的变量。
共分析了 222 只属于 17 种和 7 科的蝙蝠个体。在两个科中发现了变色嗜人菌属感染：长翼蝠科和蝙蝠科。分子数据表明，寄生在马达加斯加蝙蝠上的变色嗜人菌属形成了一个单系群，由三个具有明显宿主特异性的不同分支组成。除了分别由微型蝠属和毛腿蝠属寄生的变色嗜人菌属黑色素体和变色嗜人菌属鼠耳蝠属外，还从单个毛腿蝠属个体中鉴定出一种新的变色嗜人菌属谱系。基于本研究和文献，不同的生物和非生物因素被证明会影响蝙蝠中的变色嗜人菌属感染，这些因素基于最大熵模型相互关联。
本研究提高了对感染马达加斯加蝙蝠的变色嗜人菌属血液寄生虫的现有认识，并证实了在毛腿蝠属蝙蝠中存在一种新型变色嗜人菌属谱系。需要进一步的研究来获得这种新型谱系的其他材料，以解决其与该属已知成员的分类关系。此外，还应研究变色嗜人菌在蝙蝠中的传播方式及其对蝙蝠种群的潜在影响，以补充最大熵模型提供的结果，并最终提供宿主-寄生虫相互作用生物学的全面图景。
