First molecular investigation of haemosporidian parasites in Thai bat species

Abstract

Malaria parasites in the phylum Apicomplexa (Order: Haemosporida) infect diverse vertebrates and invertebrate hosts. At least seven genera of haemosporidian parasites have been described to exclusively infect bats. Most of these parasites remain enigmatic with a poorly known host range. Here, we investigated 271 bats belonging to 21 species and seven families from six provinces of Thailand. Overall, 124 out of 271 bats (45.8%) were positive for haemosporidian parasites, while none had Plasmodium, based on microscopic examination of blood smears and PCR amplification. We obtained 19 distinct cytochrome b ( cytb ) nucleotide haplotypes of Hepatocystis from seven bat species (families: Craseonycteridae, Hipposideridae, Pteropodidae, and Rhinolophidae). Nycteria was found in four bat species (Craseonycteridae, Emballonuridae, Megadermatidae, and Pteropodidae) and Polychromophilus in two species (Emballonuridae, Vespertilionidae). Phylogenetic analysis inferred from cytb sequences placed Hepatocystis into 2 different clades. Most Hepatocystis infections were found in insectivorous bats and clustered together with a sequence from Hipposideros larvatus in Cambodia (in subclade 1a). A single sequence of Hepatocystis obtained from a frugivorous bat, Cynopterus brachyotis , was placed in the same clade with Hepatocystis from the same bat species previously reported in Malaysia (clade 2). Nycteria in these Thai bats were clearly separated from the African isolates previously reported in bats in the family Rhinolophidae. Polychromophilus murinus from Myotis siligorensis was placed in a distinct clade (clade 2) from Polychromophilus melanipherus isolated from Taphozous melanopogon (clade 1) . These results confirmed that at least two distinct species of Polychromophilus are found in Thailand . Collectively, Hepatocystis presented no host specificity. Although Megaderma spasma seemed to be infected by only Nycteria, its respective parasite does not show specificity to only a single bat host. Polychromophilus murinus and P. melanipherus seem to infect a narrower host range or are somehow restricted to bats in the families Vespertilionidae and Emballonuridae, respectively.

Host specificity of Hepatocystis infection in short-nosed fruit bats (Cynopterus brachyotis) in Singapore

“…Our results indicate that all six novel Hepatocystis sequences from Singapore bats ( C. brachyotis ) are phylogenetically clustered within clade 2 ( Fig. 2 ) and most related to two other Hepatocystis sequences (MT136146 and DQ396146) from the same bat species, C. brachyotis, as previously reported in Thailand and Malaysia ( Arnuphapprasert et al, 2020 ). They shared a high level of nucleotide similarity (99.7%–100%) and formed a strongly supported clade (BS ML = 100%).…”

“…Bat Hepatocystis infections have only been detected in species in the suborder Yinpterochiroptera, including members of the families Pteropodidae (fruit bats), Craseonycteridae (Kitti's hog-nosed bat), Hipposideridae (Old World leaf-nosed bats) and Rhinolophidae (horseshoe bats) ( Arnuphapprasert et al, 2020 ; Boundenga et al, 2018 ; Martinsen et al, 2008 ; Schaer et al, 2017 ). Short-nosed fruit bats ( C. brachyotis ) are pteropodids with previous Hepatocystis detections in Malaysia, Singapore, and Thailand ( Arnuphapprasert et al, 2020 ; Martinsen et al, 2008 ). Hepatocystis has also been detected in several Pteropus species (flying foxes), including an individual Pteropus hypomelanus in Malaysia ( Olival et al, 2007 ) and three species ( P. alecto , P. poliocephalus , and P. scapulatus ) in Australia ( Schaer et al, 2019 ).…”

“…Hepatocystis infections in bats from Southeast Asia were originally described using microscopy, with detection of Hepatocystis pteropi in Pteropus bats in Malaysia, an undescribed species of Hepatocystis from a Hipposideros bat in Malaysia and another parasite from Cynopterus brachyotis and C. horsfieldi bats in Indonesia ( Garnham, 1966 ; Masbar et al, 1981 ; Mialhe and Landau, 1977 ). Molecular studies have contributed to our understanding of bat Hepatocystis diversity in this region, with sequence data generated from parasites in Cambodia, Malaysia, Singapore, and Thailand ( Arnuphapprasert et al, 2020 ; Duval et al, 2007 ; Martinsen et al, 2008 ). However, little is known about bat blood parasite epidemiology in Singapore.…”

Molecular characterization of Polychromophilus parasites of Scotophilus kuhlii bats in Thailand

“…Therefore, we assume that the Polychromophilus parasites of S. kuhlii in Thailand do not represent the parasites detected in Asian hipposiderid hosts nor the Polychromophilus parasite reported from K. hardwickii in Cambodia. The phylogenetic analyses resulted in the placement of Polychromophilus of S. kuhlii outside the P. melanipherus and P. murinus clades, which also contain the two recently reported Polychromophilus parasites from Thailand (Arnuphapprasert et al ., 2020 ). The Polychromophilus parasites of S. kuhlii form a group with the Guinean Polychromophilus parasites that have been suggested to represent a distinct species (Schaer et al ., 2013 ; Rosskopf et al ., 2019 ).…”

“…Two morphological studies described Polychromophilus from hipposiderid bat species in Thailand and Malaysia (Eyles et al ., 1962 ; Landau et al ., 1984 ). One molecular study published a Polychromophilus sequence from the vespertilionid bat Kerivoula hardwickii in Cambodia and a recent study published two short cytochrome b sequences for P. murinus and P. melanipherus from Myotis siligorensis (Vespertilionidae) and Taphozous melanopogon (Emballonuridae) in Thailand (Duval et al ., 2007 ; Arnuphapprasert et al ., 2020 ). Here, data are presented from molecular investigations of Polychromophilus infections in the lesser Asiatic yellow bat ( Scotophilus kuhlii ) in Thailand that were originally reported as unidentified haemosporidian parasites in a preliminary morphological study on white blood cell counts of S. kuhlii (Chumnandee and Pha-obnga, 2018 ) and add important information to the phylogeny of these neglected parasites.…”