Forecasting parasite sharing under climate change.

Species are shifting their distributions in response to climate change. This geographic reshuffling may result in novel co-occurrences among species, which could lead to unseen biotic interactions, including the exchange of parasites between previously isolated hosts. Identifying potential new host-parasite interactions would improve forecasting of disease emergence and inform proactive disease surveillance. However, accurate predictions of future cross-species disease transmission have been hampered by the lack of a generalized approach and data availability. Here, we propose a framework to predict novel host-parasite interactions based on a combination of niche modelling of future host distributions and parasite sharing models. Using the North American ungulates as a proof of concept, we show this approach has high cross-validation accuracy in over 85% of modelled parasites and find that more than 34% of the host-parasite associations forecasted by our models have already been recorded in the literature. We discuss potential sources of uncertainty and bias that may affect our results and similar forecasting approaches, and propose pathways to generate increasingly accurate predictions. Our results indicate that forecasting parasite sharing in response to shifts in host geographic distributions allow for the identification of regions and taxa most susceptible to emergent pathogens under climate change. This article is part of the theme issue 'Infectious disease macroecology: parasite diversity and dynamics across the globe'.

Rickettsia amblyommatis isolated from Amblyomma mixtum (Acari: Ixodida) from two sites in Panama.

Rickettsia amblyommatis is widely distributed in the Americas, and has been reported to infect different species of ticks within its distribution. In Panama, R. amblyommatis is the most common Rickettsia and its presence was molecularly detected in nine species of ticks and one flea species. This work described the isolation of R. amblyommatis in Vero cells by shell vial technique, from Amblyomma mixtum ticks collected from a captive tapir from Gamboa (Colon province), and a horse from El Valle de Antón (Cocle province). These represent the first isolations of R. amblyommatis in Panama.

Phylogenetics, patterns of genetic variation and population dynamics of Trypanosoma terrestris support both coevolution and ecological host-fitting as processes driving trypanosome evolution.

BACKGROUND: A considerable amount of evidence has favored ecological host-fitting, rather than coevolution, as the main mechanism responsible for trypanosome divergence. Nevertheless, beyond the study of human pathogenic trypanosomes, the genetic basis of host specificity among trypanosomes isolated from forest-inhabiting hosts remains largely unknown. METHODS: To test possible scenarios on ecological host-fitting and coevolution, we combined a host capture recapture strategy with parasite genetic data and studied the genetic variation, population dynamics and phylogenetic relationships of Trypanosoma terrestris, a recently described trypanosome species isolated from lowland tapirs in the Brazilian Pantanal and Atlantic Forest biomes. RESULTS: We made inferences of T. terrestris population structure at three possible sources of genetic variation: geography, tapir hosts and 'putative' vectors. We found evidence of a bottleneck affecting the contemporary patterns of parasite genetic structure, resulting in little genetic diversity and no evidence of genetic structure among hosts or biomes. Despite this, a strongly divergent haplotype was recorded at a microgeographical scale in the landscape of Nhecolândia in the Pantanal. However, although tapirs are promoting the dispersion of the parasites through the landscape, neither geographical barriers nor tapir hosts were involved in the isolation of this haplotype. Taken together, these findings suggest that either host-switching promoted by putative vectors or declining tapir population densities are influencing the current parasite population dynamics and genetic structure. Similarly, phylogenetic analyses revealed that T. terrestris is strongly linked to the evolutionary history of its perissodactyl hosts, suggesting a coevolving scenario between Perissodactyla and their trypanosomes. Additionally, T. terrestris and T. grayi are closely related, further indicating that host-switching is a common feature promoting trypanosome evolution. CONCLUSIONS: This study provides two lines of evidence, both micro- and macroevolutionary, suggesting that both host-switching by ecological fitting and coevolution are two important and non-mutually-exclusive processes driving the evolution of trypanosomes. In line with other parasite systems, our results support that even in the face of host specialization and coevolution, host-switching may be common and is an important determinant of parasite diversification.

A new species of Kiluluma Skrjabin, 1916 (Nematoda: Strongyloidea) from the white rhinoceros, Ceratotherium simum (Burchell) from South Africa.

A new species of Kiluluma Skrjabin, 1916, Kiluluma ornata n. sp., is described from the intestine of the white rhinoceros Ceratotherium simum (Burchell) from South Africa. The new species is virtually identical with a species described as Kiluluma sp., but not named due to a paucity of material then available. The new species most closely resembles K. solitaria Thapar, 1924 and K. ceratotherii Beveridge & Jabbar, 2013, in the possession of an undulating anterior margin of the buccal capsule but differs in the leaf crown elements which have bulbous, lip-like expansions, which are lacking in K. solitaria and K. ceratotherii.

Migratory behaviour predicts greater parasite diversity in ungulates.

Long-distance animal movements can increase exposure to diverse parasites, but can also reduce infection risk through escape from contaminated habitats or culling of infected individuals. These mechanisms have been demonstrated within and between populations in single-host/single-parasite interactions, but how long-distance movement behaviours shape parasite diversity and prevalence across host taxa is largely unknown. Using a comparative approach, we analyse the parasite communities of 93 migratory, nomadic and resident ungulate species. We find that migrants have higher parasite species richness than residents or nomads, even after considering other factors known to influence parasite diversity, such as body size and host geographical range area. Further analyses support a novel 'environmental tracking' hypothesis, whereby migration allows parasites to experience environments favourable to transmission year-round. In addition, the social aggregation and large group sizes that facilitate migration might increase infection risk for migrants. By contrast, we find little support for previously proposed hypotheses, including migratory escape and culling, in explaining the relationship between host movement and parasitism in mammals at this cross-species scale. Our findings, which support mechanistic links between long-distance movement and increased parasite richness at the species level, could help predict the effects of future environmental change on parasitism in migratory animals.

Accurate identification of Anopheles gambiae Giles trophic preferences by MALDI-TOF MS.

The determination of the trophic preferences of the Anopheles gambiae Giles (Diptera: Culicidae) is a decisive parameter for the monitoring and the prevention of malaria risk transmission. Currently, arthropod blood feeding sources are identified using immunological or molecular biology traditional techniques. Despite the effectiveness of these methods, they present several limitations, and notably, they are time-consuming and costly techniques. A recent study demonstrated that MALDI-TOF MS could be a useful tool for the identification of blood meal origins in freshly engorged mosquitoes. However, the limited number of blood vertebrate species tested to date, did not allow an assessment of the efficiency of MALDI-TOF MS in distinguishing blood MS spectra among close host species, such as humans versus primates. Therefore, in the present study, blood from ten distinct vertebrate host species, including four domestic species, four wild species, and two primates, was selected to control the reliability of MALDI-TOF MS based identification. Host blood species-specific MS profiles, up to 24h post-feeding in engorged Anopheles abdomens, were confirmed. Blind tests underlined the high specificity of MS spectra for the recognition of each host species, preventing misidentification. Nevertheless, an accurate analysis of the results from MS spectra queried against the MS database revealed that the reliability of identification is directly linked to the comprehensiveness of the MS reference database. Finally, the rapidity, the low-cost reagents, the simplicity of data analysis, and the accuracy of the tool for blood origin determination, make this proteomic strategy a promising complementary method for the elucidation of host/vector interactions.

Tziminema unachi n. gen., n. sp. (Nematoda: Strongylidae: Strongylinae) parasite of Baird's tapir Tapirus bairdii from Mexico.

A new genus and species of nematode, Tziminema unachi n. gen., n. sp. is described from the caecum and colon of Baird's tapir Tapirus bairdii (Gill, 1865), found dead in the Reserva de la Biósfera El Triunfo, Chiapas State, in the Neotropical realm of Mexico. Tziminema n. gen. differs from the other nine genera included in the Strongylinae by two main characteristics: having 7-9 posteriorly directed tooth-like structures at the anterior end of the buccal capsule, and the external surface of the buccal capsule being heavily striated. Phylogenetic analyses of the DNA sequences of the mitochondrial cytochrome c oxidase and nuclear DNA, including a partial sequence of the internal transcribed spacer 1, 5.8S and a partial sequence of the internal transcribed spacer 2 of the new taxon, confirmed its inclusion in Strongylinae and its rank as a new genus.

Remarkable richness of trypanosomes in tsetse flies (Glossina morsitans morsitans and Glossina pallidipes) from the Gorongosa National Park and Niassa National Reserve of Mozambique revealed by fluorescent fragment length barcoding (FFLB).

Trypanosomes of African wild ungulates transmitted by tsetse flies can cause human and livestock diseases. However, trypanosome diversity in wild tsetse flies remains greatly underestimated. We employed FFLB (fluorescent fragment length barcoding) for surveys of trypanosomes in tsetse flies (3086) from the Gorongosa National Park (GNP) and Niassa National Reserve (NNR) in Mozambique (MZ), identified as Glossina morsitans morsitans (GNP/NNR=77.6%/90.5%) and Glossina pallidipes (22.4%/9.5%). Trypanosomes were microscopically detected in 8.3% of tsetse guts. FFLB of gut samples revealed (GNP/NNR): Trypanosoma congolense of Savannah (27%/63%), Kilifi (16.7%/29.7%) and Forest (1.0%/0.3%) genetic groups; T. simiae Tsavo (36.5%/6.1%); T. simiae (22.2%/17.7%); T. godfreyi (18.2%/7.0%); subgenus Trypanozoon (20.2%/25.7%); T. vivax/T. vivax-like (1.5%/5.2%); T. suis/T. suis-like (9.4%/11.9%). Tsetse proboscises exhibited similar species composition, but most prevalent species were (GNP/NNR): T. simiae (21.9%/28%), T. b. brucei (19.2%/31.7%), and T. vivax/T. vivax-like (19.2%/28.6%). Flies harboring mixtures of trypanosomes were common (~ 64%), and combinations of more than four trypanosomes were especially abundant in the pristine NNR. The non-pathogenic T. theileri was found in 2.5% while FFLB profiles of unknown species were detected in 19% of flies examined. This is the first report on molecular diversity of tsetse flies and their trypanosomes in MZ; all trypanosomes pathogenic for ungulates were detected, but no human pathogens were detected. Overall, two species of tsetse flies harbor 12 species/genotypes of trypanosomes. This notable species richness was likely uncovered because flies were captured in wildlife reserves and surveyed using the method of FFLB able to identify, with high sensitivity and accuracy, known and novel trypanosomes. Our findings importantly improve the knowledge on trypanosome diversity in tsetse flies, revealed the greatest species richness so far reported in tsetse fly of any African country, and indicate the existence of a hidden trypanosome diversity to be discovered in African wildlife protected areas.

Detection of Leishmania (V) guyanensis in Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) collected from Pecari tajacu.

INTRODUCTION: Previous studies identified the presence of Leishmania infantum in Rhipicephalus sanguineus and indicated the possibility that it could transmit leishmaniasis to a variety of hosts. OBJECTIVE: To identify parasites of Leishmania (Viannia) spp. in ticks collected from wild animals in an endemic area for leishmaniasis. MATERIALS AND METHODS: We performed 81 individual DNA extractions from ticks collected from three Tapirus terrestris and three Pecari tajacu in Madre de Dios, Perú. Ticks were taxonomically identified and they were subsequently prepared to identify Leishmania (Viannia) spp. kDNA by PCR and the species of Leishmania by HRM-PCR. RESULTS: Leishmania (Viannia) kDNA was detected in three wild ticks of the species R. microplus, collected from a collard peccary (P. tajacu) hunted in the forests of Madre de Dios. The HRM-PCR showed that one of the positive samples had a kDNA curve compatible with L. (V) guyanensis. CONCLUSION: The results showed the presence of L. (V) guyanensis DNA in R. microplus possibly acquired after biting a collarde peccary. Therefore, it is important to design future studies to clarify R. microplus involvement in the transmission of leishmaniasis.

Detección de Leishmania (V) guyanensis en ejemplares de Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) recolectados en pecaríes de collar (Pecari tajacu) / Detection of Leishmania (V) guyanensis in Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) collected from Pecari tajacu

Resumen Introducción. En estudios previos se detectó la presencia de Leishmania infantum en Rhipicephalus sanguineus, lo cual planteaba la posibilidad de que R. sanguineus transmitiera la leishmaniasis a una variedad de huéspedes. Objetivo. Identificar Leishmania (Viannia) spp. en garrapatas recolectadas en animales silvestres de una zona endémica para leishmaniasis. Materiales y métodos. Se hicieron 81 extracciones individuales de ADN en las garrapatas recogidas de tres tapires o dantas (Tapirus terrestres) y tres pecaríes de collar (Pecari tajacu) cazados en Madre de Dios, Perú. Las garrapatas recolectadas se identificaron taxonómicamente y se prepararon para la identificación del cinetoblasto (kDNA) de Leishmania (Viannia) spp. mediante reacción en cadena de la polimerasa (PCR), así como de la especie de Leishmania mediante PCR de fusión de alta resolución (High Resolution Melt, HRM). Resultados. Se detectó el kDNA de Leishmania (V) spp. en tres garrapatas silvestres de R. (Boophilus) microplus, Canestrini, 1888, recolectadas en un pecarí de collar cazado en la selva de Madre de Dios. El análisis mediante HRM-PCR evidenció que una de las muestras positivas de kDNA tenía una curva compatible con L. (V) guyanensis. Conclusión. Los resultados evidenciaron la presencia de ADN de L. (V) guyanensis en R. (Boophilus) microplus, probablemente adquirida después de picar al pecarí. Es importante hacer nuevos estudios para aclarar la participación de R. (Boophilus) microplus en la transmisión de la leishmaniasis.

Abstract Introduction: Previous studies identified the presence of Leishmania infantum in Rhipicephalus sanguineus and indicated the possibility that it could transmit leishmaniasis to a variety of hosts. Objective: To identify parasites of Leishmania (Viannia) spp. in ticks collected from wild animals in an endemic area for leishmaniasis. Materials and methods: We performed 81 individual DNA extractions from ticks collected from three Tapirus terrestris and three Pecari tajacu in Madre de Dios, Perú. Ticks were taxonomically identified and they were subsequently prepared to identify Leishmania (Viannia) spp. kDNA by PCR and the species of Leishmania by HRM-PCR. Results: Leishmania (Viannia) kDNA was detected in three wild ticks of the species R. microplus, collected from a collard peccary (P. tajacu) hunted in the forests of Madre de Dios. The HRM-PCR showed that one of the positive samples had a kDNA curve compatible with L. (V) guyanensis. Conclusion: The results showed the presence of L. (V) guyanensis DNA in R. microplus possibly acquired after biting a collarde peccary. Therefore, it is important to design future studies to clarify R. microplus involvement in the transmission of leishmaniasis.

New insights from Gorongosa National Park and Niassa National Reserve of Mozambique increasing the genetic diversity of Trypanosoma vivax and Trypanosoma vivax-like in tsetse flies, wild ungulates and livestock from East Africa.

BACKGROUND: Trypanosoma (Duttonella) vivax is a major pathogen of livestock in Africa and South America (SA), and genetic studies limited to small sampling suggest greater diversity in East Africa (EA) compared to both West Africa (WA) and SA. METHODS: Multidimensional scaling and phylogenetic analyses of 112 sequences of the glycosomal glyceraldehyde phosphate dehydrogenase (gGAPDH) gene and 263 sequences of the internal transcribed spacer of rDNA (ITS rDNA) were performed to compare trypanosomes from tsetse flies from Gorongosa National Park and Niassa National Reserve of Mozambique (MZ), wild ungulates and livestock from EA, and livestock isolates from WA and SA. RESULTS: Multidimensional scaling (MDS) supported Tvv (T. vivax) and TvL (T. vivax-like) evolutionary lineages: 1) Tvv comprises two main groups, TvvA/B (all SA and WA isolates plus some isolates from EA) and TvvC/D (exclusively from EA). The network revealed five ITS-genotypes within Tvv: Tvv1 (WA/EA isolates), Tvv2 (SA) and Tvv3-5 (EA). EA genotypes of Tvv ranged from highly related to largely different from WA/SA genotypes. 2) TvL comprises two gGAPDH-groups formed exclusively by EA sequences, TvLA (Tanzania/Kenya) and TvLB-D (MZ). This lineage contains more than 11 ITS-genotypes, seven forming the lineage TvL-Gorongosa that diverged from T. vivax Y486 enough to be identified as another species of the subgenus Duttonella. While gGAPDH sequences were fundamental for classification at the subgenus, major evolutionary lineages and species levels, ITS rDNA sequences permitted identification of known and novel genotypes. CONCLUSIONS: Our results corroborate a remarkable diversity of Duttonella trypanosomes in EA, especially in wildlife conservation areas, compared to the moderate diversity in WA. Surveys in wilderness areas in WA may reveal greater diversity. Biogeographical and phylogenetic data point to EA as the place of origin, diversification and spread of Duttonella trypanosomes across Africa, providing relevant insights towards the understanding of T. vivax evolutionary history.

Description of a new species of Ixodes Latreille, 1795 (Acari: Ixodidae) and redescription of I. lasallei Méndez & Ortiz, 1958, parasites of agoutis and pacas (Rodentia: Dasyproctidae, Cuniculidae) in Central and South America.

Ixodes bocatorensis n. sp. (Acari: Ixodidae), is described based on adults ex agoutis (Rodentia: Dasyproctidae), pacas (Rodentia: Cuniculidae) and "tapir and sloth" (Perissodactyla: Tapiridae and Pilosa) from Colombia, Panama and Venezuela. Adults of I. bocatorensis n. sp. are similar to those of I. lasallei Méndez & Ortiz, 1958 but can be distinguished by the scutum dimensions, punctation pattern, gnathosoma and palpi measurements and their ratios, basis capituli anterior angle and shape of the spur of palpal segment I ventrally. For comparative purposes the female of I. lasallei is redescribed and the true male of this species is described for the first time. Studied adults of I. lasallei were found on agoutis, pacas and ocelot (Carnivora: Felidae) in Colombia, Peru and Venezuela.

First description of the male and redescription of the female of Ixodes tapirus Kohls, 1956 (Acari: Ixodidae), a parasite of tapirs (Perissodactyla: Tapiridae) from the mountains of Colombia, Costa Rica and Panama.

The male of Ixodes tapirus Kohls, 1956 (Acari: Ixodidae) is described for the first time and the female is redescribed in greater detail. Adults of I. tapirus are similar to those of Ixodes guatemalensis Kohls, 1956, Ixodes lasallei Méndez & Ortiz, 1958, Ixodes montoyanus Cooley, 1944 and Ixodes venezuelensis Kohls, 1953 but can be distinguished by their overall size, the amount of sclerotisation of the conscutum and accessory plates, the shape of the scutum, the number of punctations and their pattern on the conscutum and scutum, the depth of the punctations on the basis capituli dorsally, the shape and size of the porose areas and the size and shape of the auriculae. Adults of I. tapirus were collected from tapirs and vegetation in the mountains of Colombia, Panama and recorded from Costa Rica for the first time.

Parasites of domestic and wild animals in South Africa. XLIX. Ticks (Acari: Ixodidae) infesting white and black rhinoceroses in southern Africa.

The objectives of the study were to determine the species composition of ticks infesting white and black rhinoceroses in southern Africa as well as the conservation status of those tick species that prefer rhinos as hosts. Ticks were collected opportunistically from rhinos that had been immobilised for management purposes, and 447 white rhinoceroses (Ceratotherium simum) and 164 black rhinoceroses (Diceros bicornis) were sampled in South Africa, 61 black rhinos in Namibia, 18 white and 12 black rhinos in Zimbabwe, and 24 black rhinos in Zambia. Nineteen tick species were recovered, of which two species, Amblyomma rhinocerotis and Dermacentor rhinocerinus, prefer rhinos as hosts. A. rhinocerotis was collected only in the northeastern KwaZulu-Natal reserves of South Africa and is endangered, while D. rhinocerinus is present in these reserves as well as in the Kruger National Park and surrounding conservancies. Eight of the tick species collected from the rhinos are ornate, and seven species are regularly collected from cattle. The species present on rhinos in the eastern, moister reserves of South Africa were amongst others Amblyomma hebraeum, A. rhinocerotis, D. rhinocerinus, Rhipicephalus maculatus, Rhipicephalus simus and Rhipicephalus zumpti, while those on rhinos in the Karoo and the drier western regions, including Namibia, were the drought-tolerant species, Hyalomma glabrum, Hyalomma rufipes, Hyalomma truncatum and Rhipicephalus gertrudae. The species composition of ticks on rhinoceroses in Zambia differed markedly from those of the other southern African countries in that Amblyomma sparsum, Amblyomma tholloni and Amblyomma variegatum accounted for the majority of infestations.

Gyrostigma rhinocerontis (Diptera: Oestridae, Gasterophilinae) in white rhinoceroses (Ceratotherium simum) imported from South Africa: occurrence in Itatiba, São Paulo, Brazil / Gyrostigma rhinocerontis (Diptera: Oestridae, Gasterophilinae) em rinocerontes-brancos (Ceratotherium simum) importados da África do Sul: ocorrência em Itatiba, São Paulo

Fly larvae from the Gasterophilinae subfamily of the Oestridae family are parasites of domestic (equine) and wild (rhinos and equine) odd-hoofed ungulates (Perissodactyla). The gastric parasite of African Rhinos is Gyrostigma rhinocerontis (formerly Gyrostigma pavesii), which in its larva phase can be found in the feces of their hosts and can reach 40mm length. The adult is the largest fly in Africa, reaching 41mm long, with 71-mm wingspan. The Gyrostigma genus does not occur naturally in Brazil. There is one previous report of the occurrence of its larvae in the feces of a white rhino brought from South Africa in the 1990's, which was housed in a zoo located in Rio Grande do Sul. The present paper furnishes data from a zoo of the city of Itatiba, São Paulo state, Brazil, where Gyrostigma rhinocerontis larvae were found in 2005 in the feces of a group of white rhinos (Ceratotherium simum) legally imported from South Africa. The rhinos were kept in a breeding and preservation farm. This paper also reports the measures taken to control the case and avoid the dissemination of the parasite, calling attention to the fact of globalization, which allows international and intercontinental transit of wild animals with potential risks of adaptation of exotic parasites to new ecosystems.(AU)

As larvas dos dípteros da subfamília Gasterophilinae da família Oestridae parasitam ungulados perissodáctilos, tanto domésticos (equídeos) quanto selvagens (rinocerontes e equídeos). O parasito gástrico dos rinocerontes africanos é Gyrostigma rhinocerontis (anteriormente Gyrostigma pavesii), que na fase larval pode ser encontrada nas fezes dos hospedeiros, e chega a medir 40mm de comprimento. O adulto é a maior mosca daquele continente, atingindo até 41mm de comprimento, e envergadura de 71 mm. O gênero Gyrostigma não ocorre naturalmente no Brasil, onde anteriormente existia somente um relato do achado de larvas, nas fezes de um rinoceronte-branco oriundo da África do Sul nos anos 90 do século XX, e albergado num zoológico localizado no Rio Grande do Sul. Este artigo apresenta dados sobre o achado, em um zoológico no município de Itatiba, Estado de São Paulo, Brasil, de larvas de Gyrostigma rhinocerontis nas fezes de um grupo de rinocerontes-brancos (Ceratotherium simum) importados legalmente da África do Sul, onde eram mantidos em uma fazenda de preservação com criação manejada, em 2005. São relatadas também as medidas tomadas para controle do caso e prevenção da disseminação do parasito, e se discutem os riscos da globalização, que viabiliza o trânsito internacional e intercontinental de animais selvagens, com riscos potenciais de adaptação de parasitos exóticos a novos ecossistemas.(AU)

Three Novel Haplotypes of Theileria bicornis in Black and White Rhinoceros in Kenya.

Piroplasms, especially those in the genera Babesia and Theileria, have been found to naturally infect rhinoceros. Due to natural or human-induced stress factors such as capture and translocations, animals often develop fatal clinical piroplasmosis, which causes death if not treated. This study examines the genetic diversity and occurrence of novel Theileria species infecting both black and white rhinoceros in Kenya. Samples collected opportunistically during routine translocations and clinical interventions from 15 rhinoceros were analysed by polymerase chain reaction (PCR) using a nested amplification of the small subunit ribosomal RNA (18S rRNA) gene fragments of Babesia and Theileria. Our study revealed for the first time in Kenya the presence of Theileria bicornis in white (Ceratotherium simum simum) and black (Diceros bicornis michaeli) rhinoceros and the existence of three new haplotypes: haplotypes H1 and H3 were present in white rhinoceros, while H2 was present in black rhinoceros. No specific haplotype was correlated to any specific geographical location. The Bayesian inference 50% consensus phylogram recovered the three haplotypes monophyleticly, and Theileria bicornis had very high support (BPP: 0.98). Furthermore, the genetic p-uncorrected distances and substitutions between T. bicornis and the three haplotypes were the same in all three haplotypes, indicating a very close genetic affinity. This is the first report of the occurrence of Theileria species in white and black rhinoceros from Kenya. The three new haplotypes reported here for the first time have important ecological and conservational implications, especially for population management and translocation programs and as a means of avoiding the transport of infected animals into non-affected areas.

Host density drives macroparasite abundance across populations of a critically endangered megaherbivore.

What determines the abundance of parasites is a central question within epidemiology. Epidemiological models predict that density-dependent transmission has a principal influence on parasite abundance. However, this mechanism is seldom tested in macroparasites, perhaps because multiple, comparable populations of the same host-parasite relationship are rare. We test the influence of a range of factors on parasite abundance across 18 populations of black rhinoceros (Diceros bicornis) in South Africa. Here we show that host density strongly predicts parasite abundance at the population level for both directly and indirectly transmitted parasites. All other models were not supported. The surprising influence of a single key factor, host density, within a complex ecological system demonstrates the validity of simple epidemiological models. Establishing this previously assumed relationship between host density and parasite abundance has major implications for disease control and parasite ecology. For instance, it is central to the idea of population density thresholds for parasitism, below which a parasite would become extinct. Density-dependent transmission is also essential for calculations of the basic reproductive number, and the hypothesis that parasites may regulate host population size.

Epidemiology of Theileria bicornis among black and white rhinoceros metapopulation in Kenya.

BACKGROUND: A huge effort in rhinoceros conservation has focused on poaching and habitat loss as factors leading to the dramatic declines in the endangered eastern black rhinoceros (Diceros bicornis michaeli) and the southern white rhinoceros (Ceratotherium simum simum). Nevertheless, the role disease and parasite infections play in the mortality of protected populations has largely received limited attention. Infections with piroplasmosis caused by Babesia bicornis and Theileria bicornis has been shown to be fatal especially in small and isolated populations in Tanzania and South Africa. However, the occurrence and epidemiology of these parasites in Kenyan rhinoceros is not known. RESULTS: Utilizing 18S rRNA gene as genetic marker to detect rhinoceros infection with Babesia and Theileria, we examined blood samples collected from seven rhinoceros populations consisting of 114 individuals of black and white rhinoceros. The goal was to determine the prevalence in Kenyan populations, and to assess the association of Babesia and Theileria infection with host species, age, sex, location, season and population mix (only black rhinoceros comparing to black and white rhinoceros populations). We did not detect any infection with Babesia in the sequenced samples, while the prevalence of T. bicornis in the Kenyan rhinoceros population was 49.12% (56/114). White rhinoceros had significantly higher prevalence of infection (66%) compared to black rhinoceros (43%). The infection of rhinoceros with Theileria was not associated with animal age, sex or location. The risk of infection with Theileria was not higher in mixed species populations compared to populations of pure black rhinoceros. CONCLUSION: In the rhinoceros studied, we did not detect the presence of Babesia bicornis, while Theileria bicornis was found to have a 49.12% prevalence with white rhinoceros showing a higher prevalence (66%) comparing with black rhinoceros (43%). Other factors such as age, sex, location, and population mix were not found to play a significant role.

Sharing schistosomes: the elephant schistosome Bivitellobilharzia nairi also infects the greater one-horned rhinoceros (Rhinoceros unicornis) in Chitwan National Park, Nepal.

Because the digenetic trematode fauna of Nepal is poorly known, we began to search for schistosomes in and around Chitwan National Park (CNP) of southern Nepal. Both domestic and wild Indian elephants (Elephus maximus) are present, and we found one of two dung samples from wild elephants and 1 of 22 (4.5%) dung samples from domestic elephants to be positive for schistosome eggs. The morphology of the eggs and both cox1 and 28S sequences derived from the eggs/miracidia were consistent with Bivitellobilharzia nairi, reported here for the first time from Nepal. Also, 7 of 14 faecal samples from the Asian or greater one-horned rhinoceros (Rhinoceros unicornis) contained viable eggs indistinguishable from those of B. nairi. This identification was confirmed by comparison with both cox1 and 28S sequences from B. nairi eggs/miracidia derived from Nepalese and Sri Lankan elephants. This represents the first sequence-verified identification of a schistosome from any species of rhinoceros, and the first verified occurrence of a representative of Bivitellobilharzia (a genus of 'elephant schistosomes') in mammals other than elephants. Our work suggests that elephants and rhinos share B. nairi in CNP, even though these two members of the 'charismatic megafauna' belong to unrelated mammalian families. Their shared life style of extensive contact with freshwater habitats likely plays a role, although the snail intermediate host and mode of definitive host infection for B. nairi have yet to be documented. This report also supports Bivitellobilharzia as a monophyletic group and its status as a distinct genus within Schistosomatidae.

Morphological and molecular characterization and phylogenetic relationships of a new species of trypanosome in Tapirus terrestris (lowland tapir), Trypanosoma terrestris sp. nov., from Atlantic Rainforest of southeastern Brazil.

BACKGROUND: The Lowland tapir (Tapirus terrestris) is the largest Brazilian mammal and despite being distributed in various Brazilian biomes, it is seriously endangered in the Atlantic Rainforest. These hosts were never evaluated for the presence of Trypanosoma parasites. METHODS: The Lowland tapirs were captured in the Brazilian southeastern Atlantic Rainforest, Espírito Santo state. Trypanosomes were isolated by hemoculture, and the molecular phylogeny based on small subunit rDNA (SSU rDNA) and glycosomal-3-phosphate dehydrogenase (gGAPDH) gene sequences and the ultrastructural features seen via light microscopy and scanning and transmission electron microscopy are described. RESULTS: Phylogenetic trees using combined SSU rDNA and gGAPDH data sets clustered the trypanosomes of Lowland tapirs, which were highly divergent from other trypanosome species. The phylogenetic position and morphological discontinuities, mainly in epimastigote culture forms, made it possible to classify the trypanosomes from Lowland tapirs as a separate species. CONCLUSIONS: The isolated trypanosomes from Tapirus terrestris are a new species, Trypanosoma terrestris sp. n., and were positioned in a new Trypanosoma clade, named T. terrestris clade.