Parasitology Research

The impact of refugees on leishmaniasis in Turkey: a new Syrian/Turkish Leishmania tropica population structure described by multilocus microsatellite typing (MLMT) Abstract Turkey is one of the leishmaniasis endemic countries, and according to the recent reports, more than 45% of the cases were reported from the Southeastern part of Turkey. The disease is endemic in Syria with annually 25,000 cases, and it is emphasized by WHO that the actual number was estimated to be 2–5-fold higher than the reported numbers. Due to the civil war in Syria, more than seven million people were displaced and migrate to neighboring countries. The population structure of Leishmania tropica was investigated in the present study using clinical samples, which were obtained from Syrian patients residing in Turkey. Previously reported database was used to compare the results obtained in the present study. According to the multilocus microsatellite typing profiles, three populations (Şanlıurfa, Mediterranean, and Syrian/Turkish) were identified. Syrian/Turkish population, which is a new structure and identified for the first time in the present study, was comprised of clinical samples obtained from Syrian patients. The newly described population structure was homogeneous and solid comparing to previously identified population structures in Turkey. Further analyses revealed two sub-populations under the main Syrian/Turkish population structure. The findings of the present study revealed that the epidemiological status of leishmaniasis is more complicated than it is estimated. We believe that the data presented here will provide valuable information on the leishmaniasis epidemiology.

Serological and molecular investigation of selected parasitic pathogens in European brown hare ( Lepus europaeus ) in Greece: inferring the ecological niche of Toxoplasma gondii and Leishmania infantum in hares Abstract The occurrence of infection or exposure to Toxoplasma gondii, Neospora caninum, and Leishmania infantum was investigated in European brown hares (Lepus europaeus, EBH) hunter-harvested over two consecutive hunting seasons in northern and central Greece. Geographical information system was used along with the ecological niche model to define the geographical distribution of seropositive hares relative to environmental parameters and to identify high-risk areas for hare exposure. Molecular analysis showed that 3.8% and 9.6% of the examined hares were infected with N. caninum and L. infantum, respectively, while, 5.7%, 0.95%, and 12.4% of the hares tested positive for the presence of antibodies against T. gondii, N. caninum, and L. infantum respectively. None of the examined hares was polymerase chain reaction–positive for T. gondii. Mixed exposure against both T. gondii and L. infantum was found in 2.9% of the hares examined. Rainfall indices and land uses significantly influenced the exposure of hares to T. gondii and L. infantum. This is the first molecular and serological survey of protozoan pathogens in EBH in Greece. Furthermore, we report the environmental parameters related to hare seropositivity and present a risk map for hare exposure to T. gondii and L. infantum in northern and central Greece. The ecological niches of T. gondii and L. infantum in the hares presented herein could be applied to other regions with similar environmental and climatic conditions.

Eye fluke ( Tylodelphys clavata ) infection impairs visual ability and hampers foraging success in European perch Abstract Visual performance and environmental conditions can influence both behavioral patterns and predator-prey interactions of fish. Eye parasites can impair their host’s sensory performance with important consequences for the detection of prey, predators, and conspecifics. We used European perch (Perca fluviatilis) experimentally infected with the eye fluke Tylodelphys clavata and evaluated their feeding behavior and competitive ability under competition with non-infected conspecifics, in groups of four individuals, for two different prey species (Asellus aquaticus and Daphnia magna). To test whether the effect of T. clavata infection differs at different light conditions, we performed the experiments at two light intensities (600 and 6 lx). Foraging efficiency of perch was significantly affected by infection but not by light intensity. The distance at which infected fish attacked both prey species was significantly shorter in comparison to non-infected conspecifics. Additionally, infected fish more often unsuccessfully attacked A. aquaticus. Although the outcome of competition depended on prey species, there was a general tendency that non-infected fish consumed more of the available prey under both light intensities. Even though individual prey preferences for either A. aquaticus or D. magna were observed, we could not detect that infected fish change their prey preference to compensate for a reduced competitive foraging ability. As infection of T. clavata impairs foraging efficiency and competitive ability, infected fish would need to spend more time foraging to attain similar food intake as non-infected conspecifics; this presumably increases predation risk and potentially enhances transmission success to the final host.

Impacts of long-term insecticide treatment regimes on skdr and kdr pyrethroid resistance alleles in horn fly field populations Abstract We evaluated the effects of four different 6-year duration control strategies on the resistance levels and frequency of the pyrethroid target site resistance alleles, superkdr (skdr) and kdr, at four field populations of Haematobia irritans irritans (Linnaeus, 1758) (Diptera: Muscidae) in Louisiana, USA. Consecutive use of pyrethroid ear tags for 6 years caused a significant increase in the resistance ratio to pyrethroids as well as the frequencies of both skdr and kdrresistance alleles. After 3 years of consecutive use of pyrethroid ear tags, followed by 1 year with no treatment, and followed by 2 years with organophosphate ear tags, the resistance ratio for pyrethroid was not significantly affected, the %R-skdr significantly dropped while the %R-kdr allele remained relatively high and stable. Similar results were observed when pyrethroid ear tags were used for three consecutive years, followed by 1 year with no treatment, and followed by 2 years with endosulfan ear tags; however, this treatment resulted in a slight increase in the resistance ratio for pyrethroids. In a mosaic, the resistance ratio for pyrethroids showed a 2.5-fold increase but the skdr-kdrgenetic profiles did not change, as the %R alleles (skdr and kdr) remained low and stable through the 6 years. Lack of exposure to pyrethroid insecticides for 3 years significantly affected the skdr mutation but not the kdr mutation, preventing re-establishment of susceptibility to pyrethroids. SS-SR (skdr-kdr) individuals were responsible for the maintenance of the kdr mutation in two of the populations studied, and fitness cost seems to strongly affect the SR-RR genotype. None of the four treatment regimens evaluated in the study had satisfactory results for the management of kdr resistance alleles.

Evidence for camels ( Camelus bactrianus ) as the main intermediate host of Echinococcus granulosus sensu lato G6/G7 in Mongolia Abstract Cystic echinococcosis (CE), the parasitic disease caused by the larval stage of Echinococcus granulosus sensu lato (s.l.), is a global public health problem. In Mongolia, despite wide distribution of human CE, not enough information is available on the prevalence and molecular characterization of CE in livestock and its zoonotic linkage with human cases. We investigated the distribution of human CE cases and livestock population using statistical models to get insight into the zoonotic linkage. The incidence of human CE cases increased by a factor of 1.71 for one interquartile range increment in the density of the camel population. No significant association was observed with other livestock species. The samples collected from 96 camels and 15 goats in an endemic region showed a CE prevalence of 19.7% and 6.7%, respectively. All livestock CE were E. granulosus s.l. G6/G7 species of the E. granulosus s.l. complex. The genetic diversity was investigated using the haplotype network based on full cox1 gene analysis of the samples collected from livestock CE and nucleotide sequences previously reported from human CE and wild canids infection in Mongolia. Four haplotypes were identified within the livestock samples, two of which had not been previously reported. A common haplotype was identified among humans, camels, goats, and a wolf, all of which were within the same geographical area. A mixed infection of E. granulosus s.l. G6/G7 with different haplotypes in the intermediate host was identified. To the best of our knowledge, this is the most comprehensive description of the current epidemiological situation of CE in Mongolia with substantial evidence that camels might be the main intermediate host of E. granulosus s.l. G6/G7 in Mongolia. Moreover, our result presents the first report in the country to provide insight into the prevalence of E. granulosus s.l. G6/G7 in livestock.

In vitro and in vivo anti-parasitic activity of biogenic antimony sulfide nanoparticles on Leishmania major (MRHO/IR/75/ER) Abstract The aims of this study were to produce biogenic antimony sulfide nanoparticles (NPs) using Serratia marcescens (S. marcescens) and investigate the potential anti-leishmanial effects of these NPs on Leishmania major (L. major) (MRHO/IR/75/ER) in both in vitro and in vivo experiments. Biogenic antimony sulfide NPs were synthesized through intracellular biological methods using S. marcescens. The efficiency of various concentrations of antimony sulfide NPs was assessed using in vitro experiments on amastigotes of L. major at various times post-infection. In vivo experiments were carried out in BALB/c mice inoculated subcutaneously with 2 × 106L. major promastigotes (MHROM/IR/75/ER) and treated with antimony sulfide NPs (70 μg/mL, tropically), meglumine antimoniate (glucantime) as positive control and sterile phosphate-buffered saline (PBS, pH 7.4) as vehicle control. Results of in vitro experiments revealed that the anti-leishmanial activity increased when the antimony sulfide NPs concentration increased. The IC50 (50% inhibitory concentration) of antimony sulfide NPs against amastigotes was calculated as 62.5 μg/mL. In in vivo experiments, the average size of lesions significantly decreased to 8.6 ± 2.7 mm2 in mice inoculated with L. major promastigotes and treated with antimony sulfide NPs, compared with that in the negative control group (P = 0.015). Furthermore, results showed that antimony sulfide NPs significantly decreased the parasite load in the test group, compared with the negative control group (P = 0.001). Various concentrations of antimony sulfide NPs showed a great anti-leishmanial efficiency against L. major (MRHO/IR/75/ER), with the greatest efficiency shown by a concentration of 62.5 μg/mL in in vitro and in vivo experiments.

Quill mite infestation of rock ptarmigan Lagopus muta (Aves: Phasianidae) in relation to year and host age, sex, body condition, and density Abstract A total of 1209 ptarmigan were examined for Mironovia lagopus, including 721 juvenile birds (ca. 3 months old) and 488 adult birds (15 months or older). A total of 88 birds or 7.3% (n = 1209, 95% cl 5.9–8.9%) were infested with M. lagopus. There was an age difference in prevalence of infection, and more adults (10.7%, n = 488, 95% cl 8.2–13.7%) than juveniles (5.0%, n = 721, 95% cl 3.6–6.8%) were infested. There was a significant age effect in the mean intensity index, and adult birds had more advanced infestations compared with juvenile birds. There were no significant changes in either the interannual prevalence of infection or the mean intensity index of infection. Of the feather types inspected, there was no age-related difference in selection of feathers, nor was there any preference of mites for any one of the inspected feather types. Body dispersants were all adult females. There was an age-related difference in mean intensities of infection of body dispersants; it was higher in adult birds. The methods used to determine presence or absence of M. lagopus were not 100% accurate especially for juvenile hosts, and this at least partly explains the difference in prevalence among age groups. There was no relationship between host body condition or host density and infection by M. lagopus.

Motility and cytoskeletal organisation in the archigregarine Selenidium pygospionis (Apicomplexa): observations on native and experimentally affected parasites Abstract Representatives of Apicomplexa perform various kinds of movements that are linked to the different stages of their life cycle. Ancestral apicomplexan lineages, including gregarines, represent organisms suitable for research into the evolution and diversification of motility within the group. The vermiform trophozoites and gamonts of the archigregarine Selenidium pygospionis perform a very active type of bending motility. Experimental assays and subsequent light, electron, and confocal microscopic analyses demonstrated the fundamental role of the cytoskeletal proteins actin and tubulin in S. pygospionis motility and allowed us to compare the mechanism of its movement to the gliding machinery (the so-called glideosome concept) described in apicomplexan zoites. Actin-modifying drugs caused a reduction in the movement speed (cytochalasin D) or stopped the motility of archigregarines completely (jasplakinolide). Microtubule-disrupting drugs (oryzalin and colchicine) had an even more noticeable effect on archigregarine motility. The fading and disappearance of microtubules were documented in ultrathin sections, along with the formation of α-tubulin clusters visible after the immunofluorescent labelling of drug-treated archigregarines. The obtained data indicate that subpellicular microtubules most likely constitute the main motor structure involved in S. pygospionis bending motility, while actin has rather a supportive function.

Population genetics of the invasive Asian bush mosquito Aedes japonicus (Diptera, Culicidae) in Germany—a re-evaluation in a time period of separate populations merging Abstract The Asian bush mosquito Aedes japonicus, endemic to East Asia, is one of the most expansive mosquito species in the world and has as yet established in 15 countries of Europe. Within Germany, the species has been spreading tremendously during the last years, and its four once geographically isolated populations were on the verge of merging in 2017. To reveal relationships and carry-over ways between the various populations, and thus, migration and displacement routes, the genetic make-up of Ae. japonicus from ten different locations throughout its German distribution area was investigated. For this purpose, a part of the mitochondrial DNA (nad4 gene) of collected specimens was sequenced and seven loci of short tandem repeats (microsatellites) were genotyped. When related to similar genetic studies carried out between 2012 and 2015, the results suggest that admixtures had since occurred, but no complete genetic mixture of populations had taken place. At the time of sampling for the present study, the western collection sites were still uniform in their genetic make-up; however, a carry-over of individuals from the southeastern to the northern and southwestern German populations was determined. Further introductions from abroad are possible. In summary, the genetic diversity of Ae. japonicus in Germany had grown considerably, thus increasing ecological variability and adaptability of the species. At this point (10 years after the first detection), it is not possible anymore to draw conclusions on the origins of the populations.

Monunguis streblida (Neothrombidiidae) in Brazil and its parasitic relationships with dipteran ectoparasites ( Anastrebla and Trichobius ) of bats Abstract The mite species Monunguis streblida Wharton, 1938 (Neothrombidiidae) is reported in association with dipteran ectoparasites (Streblidae) of Brazilian bats for the first time. A 1-year study of two populations of the bat Anoura geoffroyi Gray, 1838 in caves in the state of Minas Gerais, Brazil, found them to be parasitized by four species of streblids, three of which were parasitized by M. streblida. Three hundred and thirty-two individuals of M. streblida were collected in association with 135 individuals of Anastrebla modestini Wenzel, 1966, two individuals of A. caudiferae Wenzel, 1976, and two individuals of Trichobius sp. (dugesii complex). The predominant association of M. streblidawith A. modestini suggests a preference for this host for the larvae of this mite. Fluctuations in the abundance of mites were found to accompany seasonal cycles and fluctuations in the abundance of their main host, with the mites being more abundant in months with higher temperatures and greater rainfall. The present work represents the first formal record of the occurrence of M. streblida in South America, increasing its range of occurrence southward by more than 5000 km.