Nycteria and Polychromophilus parasite infections of bats in Central Gabon

Complete mitochondrial genome analyses confirm that bat Polychromophilus and ungulate Plasmodium constitute a distinct clade independent of other Plasmodium species

In recent phylogenetic studies, bat Polychromophilus and ungulate Plasmodium, two relatively understudied haemosporidian parasites within the Apicomplexa phylum, have often been overlooked. Instead, the focus has been primarily on haemosporidian parasites in primates, rodents, and birds. Several phylogenetic analyses of bat Polychromophilus have relied on limited datasets and short informative DNA sequences. As a result of these inherent limitations, the substantiation of their evolutionary stance has encountered a diminished degree of robust validation. This study successfully obtained complete mitochondrial genome sequences from 11 Polychromophilus parasites originating from Hipposideros gentilis and Myotis siligoensis bats for the first time. Additionally, the authors have sequenced the apicoplast caseinolytic protease C genes from Polychromophilus murinus and a potentially new Polychromophilus species. These mitochondrial genomes range in length from 5994 to 6001 bp and consist of three protein-coding genes (PCGs), seven small subunit ribosomal RNA genes (SSU rRNA), 12 large subunit ribosomal RNA genes (LSU rRNA), and seven miscellaneous RNA genes. Phylogenetic analyses using Bayesian Inference and Maximum Likelihood methods indicated robust support for the grouping of ungulate Plasmodium and bat Polychromophilus in a single clade separate from other Plasmodium spp., confirming previous reports, albeit with stronger evidence in this study. The divergence between Polychromophilus in bats and Plasmodium in ungulates occurred approximately 29.61 to 55.77 million years ago (Mya), with a node age estimated at 40.63 Mya. These findings highlight that the genus Plasmodium, which includes species found in ungulates, birds, reptiles, and other mammals, does not form a monophyletic group. By incorporating Polychromophilus in bats and Plasmodium in ungulates, this study contributes significantly to understanding the phylogenetic relationships within the Haemosporida order. It provides valuable insights into the evolutionary history and interconnections among these diverse parasites, thereby expanding knowledge in this field.

Vector-borne protozoan and bacterial pathogen occurrence and diversity in ectoparasites of the Egyptian Rousette bat

Bats are known reservoir hosts for a wide variety of parasites and pathogens, including bacteria and protozoans. Some of these pathogens are vector-borne, and although their role is poorly studied, ectoparasites may contribute significantly to their transmission. The aim of this study was to molecularly detect the presence of vector-borne microorganisms in bat-associated ectoparasites to explore their diversity and distribution in these insects. We tested the presence of Bartonella spp., Polychromophilus spp., and Trypanosoma spp. in bat flies and bat fleas collected from 56 Egyptian Rousette bats (Rousettus aegyptiacus), using conventional PCR. We found a high prevalence of 43.9% (47/107) of Bartonella spp. in bat flies, but a low prevalence of 6.6% (4/61) in bat fleas. Polychromophilus and Trypanosoma DNA were absent in both bat flies and bat fleas. Furthermore, we found novel gltA Bartonella sequences, as well as genotypes that are highly similar to recently described and potentially zoonotic ones. Our results show high diversity of Bartonella in bat flies, however, their role in pathogen transmission is still unknown and should be further explored.

Non-invasive investigation of Polychromophilus parasite infections in bat populations in Serbia using bat flies

BACKGROUND

Haemosporidian parasites of the genus Polychromophilus infect bats worldwide. They are vectored by obligate ectoparasitic bat flies of the family Nycteribiidae. Despite their global distribution, only five Polychromophilus morphospecies have been described to date. The two predominant species, Polychromophilus melanipherus and Polychromophilus murinus, are broadly distributed and mainly infect miniopterid and vespertilionid bats, respectively. In areas where species from different bat families aggregate together, the infection dynamics and ability of either Polychromophilus species to infect other host families is poorly characterized.

METHODS

We collected 215 bat flies from two bat species, Miniopterus schreibersii and Rhinolophus ferrumequinum, which sometimes form mixed clusters in Serbia. Miniopterus schreibersii is known to be frequently infected with P. melanipherus, whereas R. ferrumequinum has been observed to be incidentally infected with both Polychromophilus species. All flies were screened for Polychromophilus infections using a PCR targeting the haemosporidian cytb gene. Positive samples were subsequently sequenced for 579 bp of cytochrome b (cytb) and 945 bp of cytochrome oxidase subunit 1 (cox1).

RESULTS

Polychromophilus melanipherus DNA was detected at six out of nine sampling locations and in all three examined bat fly species collected from M. schreibersii (Nycteribia schmidlii, n = 21; Penicillidia conspicua, n = 8; Penicillidia dufourii, n = 3). Four and five haplotypes were found for cytb and cox1, respectively. Evidence for multiple Polychromophilus haplotypes was found in 15 individual flies. These results point to a high diversity of P. melanipherus parasites in Miniopterus hosts and efficient transmission throughout the study area. A single Phthiridium biarticulatum bat fly collected from R. ferrumequinum screened positive for P. melanipherus, but only yielded a partial cox1 sequence fragment. Nevertheless, this result suggests that secondary hosts (both bat and fly species) are regularly confronted with this parasite.

CONCLUSIONS

The results of this study provide new insights into the prevalence and distribution of Polychromophilus parasites in European bats and their nycteribiid vectors. The use of bat flies for the non-invasive investigation of Polychromophilus infections in bat populations has proven to be efficient and thus represents an alternative for large-scale studies of infections in bat populations without the need to invasively collect blood from bats.

Isolation and molecular characterization of Polychromophilus spp. (Haemosporida: Plasmodiidae) from the Asian long-fingered bat (Miniopterus fuliginosus) and Japanese large-footed bat (Myotis macrodactylus) in Japan

Bats (order, Chiroptera) account for more than one-fifth of all mammalian species in the world and are infected by various intra-erythrocytic parasites of the family Plasmodiidae (Apicomplexa: Haemosporida), including Polychromophilus Dionisi, 1899. Recent advance in the molecular characterization of haemosporidian isolates has enabled their accurate identification, particularly in the last decade. Studies are actively conducted in tropical regions, Europe, and Australia; however, data on haemosporidian infection in bats in Asian temperate areas, including Japan, remain limited. In this study, 75 bats of 4 species (Miniopterus fuliginosus, Myotis macrodactylus, Rhinolophus nippon, and Rhinolophus cornutus) were captured at three sites in western Japan (Yamaguchi Prefecture), and haemosporidian parasites were screened microscopically and molecularly via nested polymerase chain reaction (PCR) targeting the cytochrome b (cytb), cytochrome c oxidase subunit I (cox-1), apicoplast caseinolytic protease C (clpc), and nuclear elongation factor 2 (EF2) genes. The survey detected Polychromophilus melanipherus in 15 (40.5%) miniopterid bats (M. fuliginosus) and Polychromophilus murinus in 6 (46.2%) vespertilionid bats (M. macrodactylus), whereas none of the 25 rhinolophid bats (R. nippon and R. cornutus) was infected, indicating the robust host specificity for miniopterid (P. melanipherus) and vespertilionid (P. murinus) bats regardless of orthotopic nesting. The 15 Polychromophilus cytb sequences obtained from 11 miniopterid and 4 vespertilionid bats were classified into six cytb haplotypes (three for each species), showing no region-specific variation in a phylogenetic tree of Polychromophilus isolates in the Old World. Similarly, multiple haplotypes (seven for cox-1 and nine for clpc) and genotypes (three for EF2) were characterized for the Japanese isolates of Polychromophilus, and the results were consistent with those based on a haemosporidian cytb analysis. Bat flies (Nycteribia allotopa and another undetermined Nycteribia sp.) collected from the body surface of bats harbored Polychromophilus oocysts on the external surface of the midgut. This is the first study to report the isolation and molecular characterization of Polychromophilus spp. in miniopterid and vespertilionid bats in the temperate area of Asia (western Japan). Future studies should evaluate the global prevalence of haemosporidian infections in bats.

The evolution of primate malaria parasites: A study on the origin and diversification of Plasmodium in lemurs

Among the primate malaria parasites, those found in lemurs have been neglected. Here, six Plasmodium lineages were detected in 169 lemurs. Nearly complete mitochondrial genomes (mtDNA, ≈6Kb) and apicoplast loci (≈6Kb) were obtained from these parasites and other Haemosporida species. Plasmodium spp. in lemurs are a diverse clade that shares a common ancestor with other primate parasites from continental Africa. Time-trees for the mtDNA were estimated under different scenarios, and the origin of the lemur clade coincides with the proposed time of their host species' most recent common ancestor (Lemuridae-Indriidae). A time tree with fewer taxa was estimated with mtDNA + Apicoplast loci. Those time estimates overlapped but were younger and had narrower credibility intervals than those from mtDNA alone. Importantly, the mtDNA + Apicoplast estimates that the clade including the most lethal malaria parasite in humans, Plasmodium falciparum, may have originated with Homininae (African apes). Finally, the phylogenetic congruence of the lemurs and their parasites was explored. A statistically significant scenario identified four cospeciation, two duplications, four transfer (host-switches), and zero loss events. Thus, the parasite species sampled in lemurs seem to be radiating with their hosts.

Hepatocystis and Nycteria (Haemosporida) parasite infections of bats in the Central Region of Cameroon

Mammalian haemosporidian parasites are classified in ten genera, including Plasmodium, Hepatocystis and Nycteria. A high diversity of haemosporidian parasites has been described from bats, but our understanding of their prevalence, distribution and use of hosts remain fragmented. The haemosporidian parasites of bats in Cameroon have been largely understudied, but here, bats, sampled from different habitat types of the Central Region of Cameroon, were investigated for haemosporidian infections with a combination of microscopic and molecular phylogenetic analysis. An overall prevalence of 18.1% of haemosporidian infections was detected in a total of 155 investigated bats belonging to 14 bat species. For the first time Hepatocystis and Nycteria parasites were detected in bats from Cameroon and molecularly characterized. Hepatocystis infections were exclusively identified in the epauletted fruit bat host species Epomophorus pusillus with a high prevalence of 65.5%, whereas Nycteria infections could be detected in several hosts, namely: Doryrhina cyclops (60.0%), Rhinolophus landeri (20.0%) and one Nycteris grandis. This study unveils evidence that habitat types may play a role in transmission of Hepatocystis parasites on a local scale and it adds important information on the distribution and host specificity of the neglected haemosporidian genus Nycteria.

First Molecular Detection of Polychromophilus Parasites in Brazilian Bat Species

Blood parasites of the Haemosporida order, such as the Plasmodium spp. responsible for malaria, have become the focus of many studies in evolutionary biology. However, there is a lack of molecular investigation of haemosporidian parasites of wildlife, such as the genus Polychromophilus. Species of this neglected genus exclusively have been described in bats, mainly in Europe, Asia, and Africa, but little is known about its presence and genetic diversity on the American continent. Here, we investigated 406 bats from sites inserted in remnant fragments of the Atlantic Forest and Cerrado biomes and urbanized areas from southern Brazil for the presence of Polychromophilus species by PCR of the mitochondrial cytochrome b encoding gene. A total of 1.2% of bats was positive for Polychromophilus, providing the first molecular information of these parasites in Myotis riparius and Eptesicus diminutus, common vespertilionid bats widely distributed in different Brazilian biomes, and Myotis ruber, an endangered species. A Bayesian analysis was conducted to reconstruct the phylogenetic relationships between Polychromophilus recovered from Brazilian bats and those identified elsewhere. Sequences of Brazilian Polychromophilus lineages were placed with P. murinus and in a clade distinct from P. melanipherus, mainly restricted to bats in the family Vespertilionidae. However, the sequences were split into two minor clades, according to the genus of hosts, indicating that P. murinus and a distinct species may be circulating in Brazil. Morphological observations combined with additional molecular studies are needed to conclude and describe these Polychromophilus species.

Molecular characterization of Polychromophilus parasites of Scotophilus kuhlii bats in Thailand

Parasites of the haemosporidian genus Polychromophilus have exclusively been described in bats. These parasites belong to the diverse group of malaria parasites, and Polychromophilus presents the only haemosporidian taxon that infects mammalian hosts in tropical as well as in temperate climate zones. This study provides the first information of Polychromophilus parasites in the lesser Asiatic yellow bat (Scotophilus kuhlii) in Thailand, a common vespertilionid bat species distributed in South and Southeast Asia. The gametocyte blood stages of the parasites could not be assigned to a described morphospecies and molecular analysis revealed that these parasites might represent a distinct Polychromophilus species. In contrast to Plasmodium species, Polychromophilus parasites do not multiply in red blood cells and, thus, do not cause the clinical symptoms of malaria. Parasitological and molecular investigation of haemosporidian parasites of wildlife, such as the neglected genus Polychromophilus, will contribute to a better understanding of the evolution of malaria parasites.

The buffy coat method: a tool for detection of blood parasites without staining procedures

BACKGROUND

Blood parasites belonging to the Apicomplexa, Trypanosomatidae and Filarioidea are widespread in birds and have been studied extensively. Microscopical examination (ME) of stained blood films remains the gold standard method for the detection of these infections in birds, particularly because co-infections predominate in wildlife. None of the available molecular tools can detect all co-infections at the same time, but ME provides opportunities for this to be achieved. However, fixation, drying and staining of blood films as well as their ME are relatively time-consuming. This limits the detection of infected hosts during fieldwork when captured animals should be released soon after sampling. It is an obstacle for quick selection of donor hosts for parasite experimental, histological and other investigations in the field. This study modified, tested and described the buffy coat method (BCM) for quick diagnostics (~ 20 min/sample) of avian blood parasites.

METHODS

Blood of 345 birds belonging to 42 species was collected, and each sample was examined using ME of stained blood films and the buffy coat, which was examined after centrifugation in capillary tubes and after being transferred to objective glass slides. Parasite detection using these methods was compared using sensitivity, specificity, positive and negative predictive values and Cohen's kappa index.

RESULTS

Haemoproteus, Leucocytozoon, Plasmodium, microfilariae, Trypanosoma and Lankesterella parasites were detected. BCM had a high sensitivity (> 90%) and specificity (> 90%) for detection of Haemoproteus and microfilariae infections. It was of moderate sensitivity (57%) and high specificity (> 90%) for Lankesterella infections, but of low sensitivity (20%) and high specificity (> 90%) for Leucocytozoon infections. Trypanosoma and Plasmodium parasites were detected only by BCM and ME, respectively. According to Cohen's kappa index, the agreement between two diagnostic tools was substantial for Haemoproteus (0.80), moderate for Lankesterella (0.46) and fair for microfilariae and Leucocytozoon (0.28) infections.

CONCLUSIONS

BCM is sensitive and recommended as a quick and reliable tool to detect Haemoproteus, Trypanosoma and microfilariae parasites during fieldwork. However, it is not suitable for detection of species of Leucocytozoon and Plasmodium. BCM is a useful tool for diagnostics of blood parasite co-infections. Its application might be extended to studies of blood parasites in other vertebrates during field studies.

Survey of Hepatocystis parasites of fruit bats in the Amurum forest reserve, Nigeria, identifies first host record for Rousettus aegyptiacus

Parasites of the genus Hepatocystis are close relatives of Plasmodium that frequently infect epauletted fruit bats across West and East Africa. Our understanding of susceptible hosts and prevalence of infection of Hepatocystis remains fragmented. Non-invasive sampling of bat assemblages in representative habitats critically contribute to haemosporidian parasite distribution maps. Here, we report on a survey of Hepatocystis parasite infections in bats undertaken over two consecutive years in a protected area in Nigeria, where prevalence and diversity of bat-infecting haemosporidian parasites have not been studied. Microscopic examination of blood films in combination with PCR detection and sequencing revealed Hepatocystis infections with prevalences of 25% and 42% in the closely related epauletted fruit bats Epomophorus sp. and Micropteropus pusillus. For the first time, mature Hepatocystis gametocytes were identified in one Egyptian fruit bat (Rousettus aegyptiacus). This novel host record was confirmed by parasite and host genotyping and suggests that Hepatocystis parasites have a broader host distribution in African fruit bats than currently known.