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The demographic history, population structure, and intraspecific diversity of the Globe Skimmer dragonfly Pantala flavescens Fabricius in Peninsular Malaysia were characterized based on variation of the mitochondria-encoded cytochrome c oxidase subunit I (COI) sequences. A median-joining network of 94 taxa inferred 71 unique haplotypes across four distinct geographic regions (i.e., northern, southern, central, and eastern). The distribution of these haplotypes, however, revealed no apparent geographical pattern, indicating minimal population genetic structure and high gene flow among all populations. A Mantel test showed an absence of isolation by distance (IBD), no significant association between genetic distance and geographic distance was observed. Mismatch distribution and neutrality tests provided evidence of demographic expansion during the Pleistocene dating back to 190,000–260,000 years ago. Additionally, species delimitation analyses revealed two operational taxonomic units (OTUs) within so-called P. flavescens , one restricted to the isolate from Korea; and the other representing isolates from Malaysia, Japan, and India. The present DNA analyses reflect the impact of the Quaternary glaciation in shaping the current genetic diversity and genetic structure of P. flavescens in Peninsular Malaysia. [ABSTRACT FROM AUTHOR]

• A novel clade of bat-associated Bartonella was detected in Leptocyclopodia ferrari bat flies. • Both 16 S–23 S rRNA and gltA sequences exhibited < 95 % similarity to all previously reported Bartonella spp. • New insight into the diversity of bartonellae associated with bats worldwide. Bartonelloses are emerging infectious diseases that are common in humans and animals worldwide. Several Bartonella species associated with companion animals such as Bartonella henselae and Bartonella rochalimae are species with zoonotic implications and have become a global concern. Other Bartonella species associated with wild animals, however, remain underappreciated particularly in the developing regions of the world. To explore further on this neglected bacterial agent, Leptocyclopodia ferrari (Nycteribiidae) bat flies collected from Cynopterus brachyotis (Pteropodidae), an endemic fruit bat species in Southeast Asia, were molecularly examined for the presence of Bartonella. Both 16 S–23 S ribosomal RNA intergenic spacer region and citrate synthase gene sequences exhibited less than 95 % similarity to all previously reported Bartonella spp. Further phylogenetic analysis revealed a novel clade of this Bartonella sp. with high bootstrap support. The vectorial capacity of bat flies in transmitting this novel pathogen merits further investigation. [ABSTRACT FROM AUTHOR]

• This review summarizes the infections of Rickettsiae, including the newly discovered regional species in vectors, humans and animals in Southeaswt Asia. • Issues on some unidentified Rickettsiae that elicit immune responses and production of antibodies that were cross-reactive with the antigens used are discussed. • Knowledge gaps which required attention are also identified in this review. Rickettsioses are emerging, and re-emerging diseases caused by obligate intracellular arthropod-borne bacteria that infect humans and animals worldwide. Various rickettsiae such as Orientia, Rickettsia, Anaplasma and Ehrlichia have been circulated in companion, domesticated and wild animals through bites of infected ticks, fleas, lice or mites. This review summarizes the infections of rickettsiae, including the newly discovered regional species Rickettsia thailandii, Candidatus Rickettsia sepangensis, Candidatus Rickettsia johorensis, Candidatus Rickettsia laoensis, Candidatus Rickettsia mahosotii, Candidatus Rickettsia khammouanensis, Candidatus Anaplasma pangolinii, and other novel genotypes in vectors, humans and animals in Southeast Asia. Issues on some unidentified rickettsiae that elicit immune responses and production of antibodies that are cross-reactive with the antigens used are discussed. Knowledge gaps which required attention are also identified in this review. [ABSTRACT FROM AUTHOR]

Abstract Simulium pumatense sp. nov. is described from Vietnam, and is placed in the Simulium feuerborni species-group of the subgenus Simulium (Nevermannia) Enderlein. Its morphological characteristics include the relatively smaller numbers of the following three numerical features: inner teeth of the female mandible (15–18), minute conical processes (16) on the female cibarium, and male upper-eye facets (in 15 vertical columns and 16 horizontal rows). Keys are constructed to distinguish this species from four species of the same group in Vietnam. Our molecular analysis of the DNA barcoding COI gene shows that this species is most closely related to cytoform A of the S. feuerborni complex from Thailand. [ABSTRACT FROM AUTHOR]

The epidemiology of giardiasis in rural villages in Peninsular Malaysia was examined in the context of the One Health triad that encompasses humans, animals and environment (i.e. river water). A cross-sectional study was carried out among five rural communities in Malaysia to determine the prevalence of Giardia duodenalis in humans, animals and river water. Fecal samples collected from humans and animals were examined by light microscopy. Water was sampled from the rivers adjacent to the target communities and investigated for the occurrence of Giardia cysts. The isolated cysts were further genotyped targeting the glutamate dehydrogenase and triosephosphate isomerase genes. The overall prevalence of G. duodenalis was 6.7% (18/269) and 4.7% (8/169) among humans and animals, respectively. Giardia cysts (mean concentration range: 0.10–5.97 cysts/L) were also found in adjacent rivers at four out of the five villages examined. At Kemensah and Kuala Pangsun, Giardia cysts were isolated from humans [rate: 3.7% each (of 54 each)], animals [rates: 6.3% (of 62) and 11.3% (of 16), respectively] and river water [average concentration of 9 samples each: 0.83 ± 0.81 and 5.97 ± 7.00, respectively]. For both villages at Pos Piah and Paya Lebar, 12.2% (of 98) and 6.1% (of 33) of collected human samples were infected, respectively whilst none of the collected animals samples in these villages were found to be positive. The river water samples of these two villages were also contaminated (average concentration: 0.20 ± 0.35 (of 9) and 0.10 ± 0.19 (of 3), respectively). In conclusion, Giardia cysts were simultaneously observed in the human-animal-environment (i.e., river water) interfaces in at least two of five studied communities highlighting a vital need to improve understanding on the interplay of transmission dynamics, the role of infected humans and animals in contaminating the water sources and the role of water as a vehicle of disease transmission in these communities. Indeed, this study illustrates the One Health approach which is to recognize that the optimal health of humans are interconnected with the well-being of animals and their environment. [ABSTRACT FROM AUTHOR]

Vector-borne infections are persistent public health threats worldwide. In recent years, a number of mosquito-borne viruses have emerged or re-emerged to cause major disease outbreaks. Other vector-borne pathogens, however, remain understudied and much neglected especially in the developing regions of the world including Southeast Asia. In this study, the brown dog tick Rhipicephalus sanguineus sensu lato, cat louse Felicola subrostratus , and cat fleas Ctenocephalides felis and Ctenocephalides orientis collected from free-ranging cats and dogs in Malaysia were molecularly screened for the presence of Bartonella and Rickettsia bacteria, and Dipylidium tapeworm. Our results showed the presence of Bartonella clarridgeiea , Bartonella henselae (lineage Marseille and lineage Houston-1), and Rickettsia sp. in C. felis . We also detected Rickettsia asembonensis in C. orientis and R. sanguineus s.l. Additionally, this study provides the first documentation on a potentially new species of Dipylidium infecting F. subrostratus and C. felis . Our results highlight the role of ectoparasites from free-ranging animals including cats and dogs, in harboring multiple transmissible pathogens. [ABSTRACT FROM AUTHOR]

• High levels of genetic diversity and genetic differentiation were observed among three common species S. vanluni, S. cheongi and S.jeffreyi in Peninsular Malaysia. • All three species revealed an intermediate level of gene flow among the populations. • The expansion time of S. vanluni was estimated at about 233 112 years ago, followed by S. jeffreyi (232, 948 years ago) and S. cheongi (191, 845 years ago). The population genetic structures of S. vanluni, S. cheongi and S. jeffreyi were determined from mitochondria-encoded sequences of cytochrome c oxidase subunits I (COI) across different states in Peninsular Malaysia. High levels of genetic diversity and genetic differentiation were observed among three species. All three species revealed an intermediate level of gene flow among the populations. Negative values of Fu's Fs and low values of Raggedness index supported the hypothesis of population expansion in S. vanluni, S. cheongi and S. jeffreyi. [ABSTRACT FROM AUTHOR]

Blackflies (Diptera: Simuliidae) are ecologically and medically important insects but they have been understudied in Malaysia. Accordingly, a study on the temporal variation in diversity and community structure of preimaginal blackflies was conducted for the first time in Malaysia. A total of 865 preimaginal blackflies were collected in 120 samplings from five streams across three monsoon seasons from February 2018 until January 2019. Ten species were recorded and most frequently collected species were Simulium cheongi, Simulium vanluni and Simulium jeffreyi. Relatively common species were Simulium roslihashimi, Simulium tani complex and Simulium trangense. No significant changes of rainfall was observed between three monsoon seasons as well as the seasons with species and physiochemical parameters except acidity (pH) (P < 0.01). Species relative abundance was varied between seasons, as high value of Shannon index (H) was found in northeast monsoon and lowest in the southwest monsoon. Principal Component Analysis (PCA) of all stream variables revealed two PCs that accounted for 61.4% of the total variance of physicochemical characteristics. Regression analysis revealed that species richness was positively and significantly associated with wider, deeper, faster, low conductivity and larger streambed particle with less canopy cover. Forward logistic regression analysis on three frequently collected species (>20%) indicated that S. vanluni and S. jeffreyi were commonly associated with wider, deeper and fast-flowing streams with low conductivity and larger streambed particle. In contrast, S. cheongi was associated with smaller, slower and small streambed particle. This first extensive bimonthly study has uncovered the species community structure as well as the changes of stream physicochemical parameters over time although they were not greatly and significantly influenced by the monsoon seasons. Species distribution, richness and abundance, however, were highly determined by the stream width, depth and velocity, therefore, were vital in shaping diversity and community structure of preimaginal blackflies. [ABSTRACT FROM AUTHOR]

Abstract Simulium (Gomphostilbia) aziruni Takaoka, Hashim & Chen was described initially based only on a pupa and a mature larva collected from Peninsular Malaysia. Herein, we describe the morphological characters of the female of S. aziruni for the first time. It resembles those of the other members of the Simulium gombakense species-group by the genital fork with a distinct projection directed medioposteriorly from each arm and claw with a large basal tooth. Cytochrome c oxidase I (COI) barcoding analysis indicates that S. aziruni is the sister species of S. maleewongae , but both are distantly separated by a genetic distance of 4.9%. [ABSTRACT FROM AUTHOR]