Nejvíce citovaný článek - PubMed ID 29116455
Do habituation, host traits and seasonality have an impact on protist and helminth infections of wild western lowland gorillas?
Cestodes of the family Anoplocephalidae parasitize a wide range of usually herbivorous hosts including e.g. rodents, ungulates, primates, elephants and hyraxes. While in some hosts, the epidemiology of the infection is well studied, information is lacking in others. In this study of mountain gorillas in the Virunga Massif, an extensive sample set comprising adult cestodes collected via necropsies, proglottids shed in feces, and finally, fecal samples from both night nests and identified individuals were analysed. Anoplocephala gorillae was the dominant cestode species detected in night nest samples and individually known gorillas, of which only 1 individual hosted a Bertiella sp. It was shown that the 2 species can be distinguished through microscopy based on egg morphology and polymerase chain reaction (PCR) assays for diagnostics of both species were provided. Sequences of mitochondrial (cox 1) and nuclear (ITS1, 18S rDNA, 28S rDNA) markers were used to evaluate the phylogenetic position of the 2 cestodes detected in mountain gorillas. Both types of fecal samples, from night nests and from identified individuals, provided comparable information about the prevalence of anoplocephalid cestodes, although the analysis of samples collected from identified gorilla individuals showed significant intra-individual fluctuation of A. gorillae egg shedding within a short period. Therefore, multiple samples should be examined to obtain reliable data for wildlife health management programmes, especially when application of anthelmintic treatment is considered. However, while A. gorillae is apparently a common symbiont of mountain gorillas, it does not seem to impair the health of its host.
- Klíčová slova
- Anoplocephala, Anoplocephalidae, Bertiella, Gorilla beringei, Rwanda, mountain gorilla, parasite ecology, parasite epidemiology,
- MeSH
- Cestoda * genetika MeSH
- fylogeneze MeSH
- Gorilla gorilla * MeSH
- ribozomální DNA MeSH
- veřejné parky MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Rwanda epidemiologie MeSH
- Názvy látek
- ribozomální DNA MeSH
Primates are an important source of infectious disease in humans. Strongyloidiasis affects an estimated 600 million people worldwide, with a global distribution and hotspots of infection in tropical and subtropical regions. Recently added to the list of neglected tropical diseases, global attention has been demanded in the drive for its control. Through a literature review of Strongyloides in humans and non-human primates (NHP), we analysed the most common identification methods and gaps in knowledge about this nematode genus. The rise of molecular-based methods for Strongyloides detection is evident in both humans and NHP and provides an opportunity to analyse all data available from primates. Dogs were also included as an important host species of Strongyloides and a potential bridge host between humans and NHP. This review highlights the lack of molecular data across all hosts-humans, NHP and dogs-with the latter highly underrepresented in the database. Despite the cosmopolitan nature of Strongyloides, there are still large gaps in our knowledge for certain species when considering transmission and pathogenicity. We suggest that a unified approach to Strongyloides detection be taken, with an optimized, repeatable molecular-based method to improve our understanding of this parasitic infection. This article is part of the Theo Murphy meeting issue 'Strongyloides: omics to worm-free populations'.
- Klíčová slova
- Strongyloides, microscopy, molecular methods, primates,
- MeSH
- lidé MeSH
- opomíjené nemoci MeSH
- primáti MeSH
- psi MeSH
- Strongyloides * MeSH
- strongyloidiáza * epidemiologie veterinární diagnóza MeSH
- veřejné zdravotnictví MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- psi MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
The Virunga Massif mountain gorilla population has been periodically monitored since the early 1970s, with gradually increasing effort. The population declined drastically in the 1970s, but the numbers stabilized in the 1980s. Since then, the population has been steadily increasing within their limited habitat fragment that is surrounded by a dense human population. We examined fecal samples collected during the Virunga 2015-2016 surveys in monitored and unmonitored gorilla groups and quantified strongylid and tapeworm infections using egg counts per gram to determine environmental and host factors that shape these helminth infections. We showed that higher strongylid infections were present in gorilla groups with smaller size of the 500-m buffered minimum-convex polygon (MCP) of detected nest sites per gorilla group, but in higher gorilla densities and inhabiting vegetation types occurring at higher elevations with higher precipitation and lower temperatures. On the contrary, the impact of monitoring (habituation) was minor, detected in tapeworms and only when in the interaction with environmental variables and MCP area. Our results suggest that the Virunga mountain gorilla population may be partially regulated by strongylid nematodes at higher gorilla densities. New health challenges are probably emerging among mountain gorillas because of the success of conservation efforts, as manifested by significant increases in gorilla numbers in recent decades, but few possibilities for the population expansion due to limited amounts of habitat.
- Klíčová slova
- Environmental and host factors, Helminth infection, Mountain gorilla, Strongylid nematode, Tapeworm,
- Publikační typ
- časopisecké články MeSH
Human disturbance is an ongoing threat to many wildlife species, manifesting as habitat destruction, resource overuse, or increased disease exposure, among others. With increasing human: non-human primate (NHP) encounters, NHPs are increasingly susceptible to human-introduced diseases, including those with parasitic origins. As such, epidemiology of parasitic disease is becoming an important consideration for NHP conservation strategies. To investigate the relationship between parasite infections and human disturbance we studied yellow baboons (Papio cynocephalus) living outside of national park boundaries in western Tanzania, collecting 135 fresh faecal samples from nine troops occupying areas with varying levels of human disturbance. We fixed all samples in 10% formalin and later evaluated parasite prevalence and abundance (of isotrichid ciliates and Strongylida). We identified seven protozoan and four helminth taxa. Taxa showed varied relationships with human disturbance, baboon troop size and host age. In four taxa, we found a positive association between prevalence and troop size. We also report a trend towards higher parasite prevalence of two taxa in less disturbed areas. To the contrary, high levels of human disturbance predicted increased abundance of isotrichid ciliates, although no relationship was found between disturbance and Strongylida abundance. Our results provide mixed evidence that human disturbance is associated with NHP parasite infections, highlighting the need to consider monitoring parasite infections when developing NHP conservation strategies.
- MeSH
- cizopasní červi fyziologie MeSH
- ekosystém MeSH
- feces parazitologie MeSH
- gastrointestinální nemoci epidemiologie parazitologie MeSH
- helmintózy zvířat epidemiologie parazitologie MeSH
- lidé MeSH
- lidské činnosti statistika a číselné údaje MeSH
- nemoci opic epidemiologie parazitologie MeSH
- Papio cynocephalus parazitologie MeSH
- parazitární nemoci střev epidemiologie veterinární MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Tanzanie MeSH
BACKGROUND: Zoonotic diseases are a serious threat to both public health and animal conservation. Most non-human primates (NHP) are facing the threat of forest loss and fragmentation and are increasingly living in closer spatial proximity to humans. Humans are infected with soil-transmitted helminths (STH) at a high prevalence, and bidirectional infection with NHP has been observed. The aim of this study was to determine the prevalence, genetic diversity, distribution and presence of co-infections of STH in free-ranging gorillas, chimpanzees and other NHP species, and to determine the potential role of these NHP as reservoir hosts contributing to the environmental sustenance of zoonotic nematode infections in forested areas of Cameroon and Gabon. METHODS: A total of 315 faecal samples from six species of NHPs were analysed. We performed PCR amplification, sequencing and maximum likelihood analysis of DNA fragments of the internal transcribed spacer 2 (ITS2) nuclear ribosomal DNA to detect the presence and determine the genetic diversity of Oesophagostomum spp., Necator spp. and Trichuris spp., and of targeted DNA fragments of the internal transcribed spacer 1 (ITS1) to detect the presence of Ascaris spp. RESULTS: Necator spp. infections were most common in gorillas (35 of 65 individuals), but also present in chimpanzees (100 of 222 individuals) and in one of four samples from greater spot-nosed monkeys. These clustered with previously described type II and III Necator spp. Gorillas were also the most infected NHP with Oesophagostomum (51/65 individuals), followed by chimpanzees (157/222 individuals), mandrills (8/12 samples) and mangabeys (7/12 samples), with O. stephanostomum being the most prevalent species. Oesophagostomum bifurcum was detected in chimpanzees and a red-capped mangabey, and a non-classified Oesophagostomum species was detected in a mandrill and a red-capped mangabey. In addition, Ternidens deminutus was detected in samples from one chimpanzee and three greater spot-nosed monkeys. A significant relative overabundance of co-infections with Necator and Oesophagostomum was observed in chimpanzees and gorillas. Trichuris sp. was detected at low prevalence in a gorilla, a chimpanzee and a greater spot-nosed monkey. No Ascaris was observed in any of the samples analysed. CONCLUSIONS: Our results on STH prevalence and genetic diversity in NHP from Cameroon and Gabon corroborate those obtained from other wild NHP populations in other African countries. Future research should focus on better identifying, at a molecular level, the species of Necator and Oesophagostomum infecting NHP and determining how human populations may be affected by increased proximity resulting from encroachment into sylvatic STH reservoir habitats.
- Klíčová slova
- Africa, Faeces, Non-human primate, Phylogeny, Soil-transmitted helminths, Zoonosis,
- MeSH
- cizopasní červi klasifikace genetika izolace a purifikace MeSH
- divoká zvířata parazitologie MeSH
- DNA helmintů genetika MeSH
- feces parazitologie MeSH
- helmintózy zvířat epidemiologie přenos MeSH
- primáti klasifikace parazitologie MeSH
- půda parazitologie MeSH
- zoonózy epidemiologie parazitologie přenos MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Gabon epidemiologie MeSH
- Kamerun epidemiologie MeSH
- Názvy látek
- DNA helmintů MeSH
- půda MeSH
Conservation efforts have led to the recovery of the endangered mountain gorilla populations. Due to their limited potential for spatial expansion, population densities increased, which may alter the epidemiology of infectious diseases. Recently, clinical gastrointestinal illnesses linked to helminth infections have been recorded in both gorilla populations. To understand drivers and patterns of helminth infections we quantified strongylid and tapeworm infections across both Virunga Massif and Bwindi populations using fecal egg counts. We assessed the impact of age, sex, group size, season and spatial differences used as a proxy, which reflects observed variation in the occurrence of gastrointestinal problems, vegetation types, gorilla subpopulation growth and associated social structure on helminth infections. We revealed striking geographic differences in strongylid infections with higher egg counts mostly in areas with high occurrences of gastrointestinal disease. Increased helminth egg counts were also associated with decreasing group size in some areas. Observed spatial differences may reflect mutual effects of variations in subpopulation growth rates, gorilla social structure, and vegetation associated with altitude across mountain gorilla habitat. Helminth infection intensities in Virunga gorillas were lowest in the youngest and the oldest animals. Elucidating parasite infection patterns of endangered species with low genetic diversity is crucial for their conservation management.
- MeSH
- biologická variabilita populace * MeSH
- helmintózy zvířat epidemiologie parazitologie MeSH
- nemoci lidoopů diagnóza epidemiologie parazitologie MeSH
- veřejné parky MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
- Geografické názvy
- Kalifornie epidemiologie MeSH
We investigated intestinal trichomonads in western lowland gorillas, central chimpanzees and humans cohabiting the forest ecosystem of Dzanga-Sangha Protected Area in Central African Republic, using the internal transcribed spacer (ITS) region and SSU rRNA gene sequences. Trichomonads belonging to the genus Tetratrichomonas were detected in 23% of the faecal samples and in all host species. Different hosts were infected with different genotypes of Tetratrichomonas. In chimpanzees, we detected tetratrichomonads from 'novel lineage 2', which was previously reported mostly in captive and wild chimpanzees. In gorillas, we found two different genotypes of Tetratrichomonas. The ITS region sequences of the more frequent genotype were identical to the sequence found in a faecal sample of a wild western lowland gorilla from Cameroon. Sequences of the second genotype from gorillas were almost identical to sequences previously obtained from an anorexic French woman. We provide the first report of the presence of intestinal tetratrichomonads in asymptomatic, apparently healthy humans. Human tetratrichomonads belonged to the lineage 7, which was previously reported in domestic and wild pigs and a domestic horse. Our findings suggest that the ecology and spatial overlap among hominids in the tropical forest ecosystem has not resulted in exchange of intestinal trichomonads among these hosts.
- Klíčová slova
- Chimpanzee, Parabasalia, Tetratrichomonas, gorilla, human, transmission, trichomonads,
- MeSH
- feces parazitologie MeSH
- fylogeneze MeSH
- Gorilla gorilla parazitologie MeSH
- hostitelská specificita MeSH
- lidé MeSH
- nemoci lidoopů epidemiologie parazitologie MeSH
- Pan troglodytes parazitologie MeSH
- protozoální infekce zvířat epidemiologie parazitologie MeSH
- protozoální infekce epidemiologie parazitologie MeSH
- Trichomonadida klasifikace MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Středoafrická republika epidemiologie MeSH
Relationships between gastrointestinal parasites (GIPs) and the gastrointestinal microbiome (GIM) are widely discussed topics across mammalian species due to their possible impact on the host's health. GIPs may change the environment determining alterations in GIM composition. We evaluated the associations between GIP infections and fecal microbiome composition in two habituated and two unhabituated groups of wild western lowland gorillas (Gorilla g. gorilla) from Dzanga Sangha Protected Areas, Central African Republic. We examined 43 fecal samples for GIPs and quantified strongylid nematodes. We characterized fecal microbiome composition through 454 pyrosequencing of the V1-V3 region of the bacterial 16S rRNA gene. Entamoeba spp. infections were associated with significant differences in abundances of bacterial taxa that likely play important roles in nutrition and metabolism for the host, besides being characteristic members of the gorilla gut microbiome. We did not observe any relationships between relative abundances of several bacterial taxa and strongylid egg counts. Based on our findings, we suggest that there is a significant relationship between fecal microbiome and Entamoeba infection in wild gorillas. This study contributes to the overall knowledge about factors involved in modulating GIM communities in great apes.
- Klíčová slova
- Entamoeba, bacteria, fecal microbiome, lowland gorilla, parasite infection, strongylid nematodes,
- Publikační typ
- časopisecké články MeSH
Strongylid nematodes in large terrestrial herbivores such as great apes, equids, elephants, and humans tend to occur in complex communities. However, identification of all species within strongylid communities using traditional methods based on coproscopy or single nematode amplification and sequencing is virtually impossible. High-throughput sequencing (HTS) technologies provide opportunities to generate large amounts of sequence data and enable analyses of samples containing a mixture of DNA from multiple species/genotypes. We designed and tested an HTS approach for strain-level identification of gastrointestinal strongylids using ITS-2 metabarcoding at the MiSeq Illumina platform in samples from two free-ranging non-human primate species inhabiting the same environment, but differing significantly in their host traits and ecology. Although we observed overlapping of particular haplotypes, overall the studied primate species differed in their strongylid nematode community composition. Using HTS, we revealed hidden diversity in the strongylid nematode communities in non-human primates, more than one haplotype was found in more than 90% of samples and coinfections of more than one putative species occurred in 80% of samples. In conclusion, the HTS approach on strongylid nematodes, preferably using fecal samples, represents a time and cost-efficient way of studying strongylid communities and provides a resolution superior to traditional approaches.
- MeSH
- feces parazitologie MeSH
- genetická variace MeSH
- infekce hlísticemi řádu Strongylida genetika parazitologie MeSH
- koně genetika parazitologie MeSH
- nemoci koní genetika parazitologie MeSH
- rozptýlené repetitivní sekvence genetika MeSH
- Strongylida klasifikace genetika MeSH
- sympatrie MeSH
- taxonomické DNA čárové kódování * MeSH
- vysoce účinné nukleotidové sekvenování MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH