Occurrence and genetic characterization of Giardia duodenalis from captive nonhuman primates by multi-locus sequence analysis

Gastrointestinal Parasites in Non-Human Primates in Zoological Gardens in Northern Italy

Non-human primates (NHPs) host a variety of helminth and protist parasites that are able to cause infection in humans. Gastrointestinal parasites in NHPs living in two zoological gardens of Northern Italy were studied. An total of 96 faecal pools were collected from 26 groups of NHPs. The mini-Flotac method was applied to fecal samples to detect gastrointestinal helminthiases, while the detection of the protists Cryptosporidium spp., Blastocystis sp. and Giardia duodenalis was performed by targeting SSU rRNA through nested PCR and real-time PCR; they were further studied by sequencing the same gene for Blastocystis and βgiardine and triosephosphate isomerase (TPI) genes for Giardia. Twenty-two out of the 96 examined fecal pools (22.9%) were positive for one or more helminth species, including Hymenolepis diminuta, Trichurid, Capillariid and Strongylid eggs. All samples were negative for Cryptosporidium spp., while 16/26 (61.5%) animals were positive for G. duodenalis in the real-time PCR; the sequences obtained assigned them all to sub-assemblage BIV. Blastocystis sp. was detected in 22/26 of the NHPs (84.6%); molecular analyses attributed the isolates to ST 4, allele 92. Analyses of the feces of sympatric rats revealed the presence of the same allele, as well as of Hymenolepis diminuta eggs, raising concern about their role as parasite reservoirs in the facilities.

Diversity of gastrointestinal parasites and molecular characterization of Giardia duodenalis in free-living and captive howler monkeys (Alouatta guariba clamitans) in southern Brazil

Non-human primates (NHPs) are the group that most share infectious agents with humans due to their close taxonomic relationship. The southern brown howler monkeys (Alouatta guariba clamitans) are endemic primates from Brazil and Argentina's Atlantic Forest. This study aimed to investigate the presence of intestinal parasites in free-living (FL) and captive (CA) southern brown howler monkeys. Thirty-nine stool samples were collected in two areas in southern Brazil, 15 FL and 24 CA. Stool sediments obtained by centrifugal sedimentation technique were used for microscopic analysis and direct immunofluorescence assay and evaluated by molecular analysis through amplification and sequencing of TPI fragments. Intestinal parasites Giardia duodenalis, Cryptosporidium spp., and Trypanoxyuris minutus were detected at coproparasitological analysis. This is the first report of the presence of Cryptosporidium spp. in free-living howlers. The molecular characterization of G. duodenalis isolates indicated assemblage B for the first time found in free-living A. guariba clamitans. The high prevalence of G. duodenalis transmission in CA howler monkeys can be explained by direct contact with humans and frequent soil contact. The presence of a potentially zoonotic assemblage in these animals indicates that the process of fragmentation and cohabitation with humans and livestock affects the wildlife, thus indicating a need for eco-health measures.

Wild Animals in Captivity: An Analysis of Parasite Biodiversity and Transmission among Animals at Two Zoological Institutions with Different Typologies

We have conducted a 10-year-long coprological study of the animals housed in two zoological institutions (ZooAquarium and Faunia, Madrid, Spain) to assess the parasite biodiversity, prevalence, and their relation with host class, diet, and enclosure type (soil type and level of isolation from wild fauna). A total of 4476 faecal samples from 132 mammal species and 951 samples from 86 avian species were examined. The results indicated that only 12.8% of avian species had parasites at least once during the study period, whereas 62.1% of mammal species tested positive. Predominantly, protists (Entamoeba, flagellates, and ciliates) and nematodes (mainly Trichuris) were identified in the findings. Carnivorous species were primarily infected by nematodes, while herbivorous and omnivorous species were mainly infected by protists. The number of infected herbivorous and omnivorous species was significantly greater than carnivorous species. Differences were observed based on soil type (artificial, natural, mixed) and isolation level (isolated/accessible), but these differences were not statistically significant. Several parasites (Entamoeba spp., Giardia spp., Balantidoides coli, Trichuris spp.) could potentially be transmitted between humans and some mammals and birds. Regular animal analyses and a personnel health program in the institutions would minimise transmission risks between zoo animals, wildlife, and humans.

Single and Synergistic Effects of Fenbendazole and Metronidazole Against Subclinical Infection by Giardia duodenalis in Non-Human Primates in a Zoological Garden in Southern Italy

The aim of this study was to assess the single and synergistic effects of fenbendazole (Fenb) and metronidazole (Metro) for the treatment of Giardia duodenalis infection in different species of non-human primates (NHPs) housed in a zoological garden of southern Italy. Moreover, the study also aimed to better define the circulation of G. duodenalis zoonotic assemblages in NHP and the potential occurrence of zoonotic transmission between the staff from the zoo and NHP. Briefly, six species that belonged to four families (Lemuridae, Cercopithecidae, Atelidae, and Hylobatidae) of NHP and housed in six cages (CG) were identified as Giardia positive and divided into two groups. Group F (N = 16 animals) was treated with Fenb (50 mg/kg, every 24 h for 5 consecutive days) and Group M (N = 7 animals) was treated with Metro (25 mg/kg, two times a day for 5 consecutive days). After the first round of therapy, all the animals were retreated for 5 days by inverting the drugs in each group. On each sampling day [study days (SDs) 3–24], the samples were tested for the presence of Giardia cysts using the FLOTAC technique. Multiple fecal tests for the antigen detection of Giardia, such as rapid ELISA and direct immunofluorescence (IFA), were performed at each sampling point only on samples that resulted in positive for Giardia cysts with FLOTAC. The efficacy of Fenb ranged from 30 to 67% and for Metro ranged from 82 to 96%. The results showed the synergistic effects of Metro and Fenb (98–100%) over the combination of Fenb and Metro (52–90%) against the infection by Giardia in NHPs. The overall k agreement between FLOTAC and IFA was reached 0.858 (p = 0.0001). In contrast, all the samples had a negative antigen result when using ELISA. At molecular analysis, six samples were confirmed positive for Giardia by nested PCR. Only two positive samples were successfully sequenced that showed 100% of identity with assemblage B. All the samples from the humans included in the study resulted in negative for Giardia cysts. Overall, the study emphasizes the need for regular monitoring of Giardia infections in NHP housed in zoos by traditional diagnostic tools combined with molecular characterization of the parasite.

Giardia duodenalis in a clinically healthy population of captive zoo chimpanzees: Rapid antigen testing, diagnostic real-time PCR and faecal microbiota profiling

Giardia duodenalis is one of the most common intestinal parasites of humans, with a worldwide distribution. Giardia duodenalis has been reported in both wild and captive populations of non-human primates, namely chimpanzees. In this study we investigated an entire troop of clinically healthy chimpanzees (n = 21) for the presence of G. duodenalis and its association with faecal microbiota profile. Faecal samples (n = 26) were collected from the chimpanzee exhibit from a zoo in Sydney, Australia. Diagnosis of G. duodenalis was made using a Rapid Antigen Test (RAT) as a point-of-care-test and compared to a reference standard real-time PCR test. Approximately half of the chimpanzee faecal samples tested positive for G. duodenalis by both RAT (13/26, 50%) and real-time PCR (14/26, 53.85%). The RAT sensitivity was 85.7% (95% CI: 63.8%–96%) and specificity was 91.7% (95% CI: 68.3%–99%) when compared to the in-house real-time PCR. Genotyping of the samples revealed the presence of zoonotic assemblage B. Microscopic analysis revealed the presence of Troglodytella spp. (14/26), Balantioides sp. (syn. Balantidium sp.) (8/26) as well as Entamoeba spp. (3/26). Microbiota profile based on 16S rRNA gene sequencing revealed that the community was significantly different between G. duodenalis positive and negative samples if RAT results were taken into an account, but not real-time PCR diagnostics results. Proteobacteria and Chloroflexi were the significant features in the dataset that separated G. duodenalis positive and negative samples using LEfSe analysis. Being able to rapidly test for G. duodenalis in captive populations of primates assists in point-of-care diagnostics and may better identify animals with subclinical disease. Under the investigated conditions of the zoo setting, however, presence of G. duodenalis either detected by RAT or real-time PCR was not associated with clinically apparent disease in captive chimpanzees.

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Whole troop investigation of healthy captive chimpanzees for Giardia duodenalis.

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Whole chimpanzee troop faecal microbiota profiled.

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Diagnosing G. duodenalis with Rapid Antigen Test (RAT) as a point-of-care-test.

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Comparison of RAT and reference real-time PCR test.

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Presence of G. duodenalis assemblage B.

Intestinal Protists in Captive Non-human Primates and Their Handlers in Six European Zoological Gardens. Molecular Evidence of Zoonotic Transmission

We assessed the occurrence, genetic diversity, and zoonotic potential of four protozoan (Cryptosporidium spp., Entamoeba histolytica, Entamoeba dispar, Giardia duodenalis), one stramenopile (Blastocystis sp.), one microsporidia (Enterocytozoon bieneusi), and two ciliate (Balantioides coli, Troglodytella abrassarti) intestinal parasite or commensal protist species in captive non-human primates (NHP) and their zookeepers from six European zoological gardens in France (n = 1), Germany (n = 1), and Spain (n = 4). Faecal samples from NHP (n = 454) belonging to 63 species within 35 genera and humans (n = 70) were collected at two sampling periods in each participating institution between October 2018-August 2021. Detection and species identification was accomplished by PCR and Sanger sequencing of the ssu rRNA and/or ITS genes. Sub-genotyping analyses using specific markers were conducted on isolates positive for G. duodenalis (gdh, bg, tpi) and Cryptosporidium spp. (gp60). Overall, 41.0% (186/454) and 30.0% (21/70) of the faecal samples of NHP and human origin tested positive for at least one intestinal protist species, respectively. In NHP, Blastocystis sp. was the most prevalent protist species found (20.3%), followed by G. duodenalis (18.1%), E. dispar (7.9%), B. coli and T. abrassarti (1.5% each), and Cryptosporidium spp. and E. bieneusi (0.9% each). Occurrence rates varied largely among NHP host species, sampling periods, and zoological institutions. The predominant protist species found in humans was Blastocystis sp. (25.7%), followed by Cryptosporidium spp. (2.9%), E. dispar (1.4%), and G. duodenalis (1.4%). Sequencing of PCR-positive amplicons in human and/or NHP confirmed the presence of Cryptosporidium in six isolates (C. hominis: 66.7%, C. parvum: 33.3%), G. duodenalis in 18 isolates (assemblage A: 16.7%, assemblage B: 83.3%), Blastocystis in 110 isolates (ST1:38.2%, ST2:11.8%, ST3: 18.2%, ST4: 9.1%, ST5: 17.3%, ST8: 2.7%, ST13: 0.9%), and E. bieneusi in four isolates (CM18: 75.0%, Type IV: 25.0%). Zoonotic transmission events involving Blastocystis ST1-ST4 were identified in four zoological institutions. Zoonotic transmission of C. hominis was highly suspected, but not fully demonstrated, in one of them. Monitoring of intestinal protist species might be useful for assessing health status of captive NHP and their zookeepers, and to identify transmission pathways of faecal-orally transmitted pathogens.

Frequency of enteroparasites in Cebidae and Callitrichidae primates at the Zoológico de Cali, Colombia: zoonotic implications

Introduction: Enteroparasites can cause problems in animals kept under human care in zoos and shelters. Wild animals have low parasitic loads but when sheltered in closed places they can be higher and lead to clinical manifestations, which increases the cost of medical treatments and care. On the other hand, some enteroparasites can represent a potential risk of zoonotic infection for their animal keepers, visitors, and other zoo animals. In addition, they could affect recovery programs for endangered species. Objectives: To establish the presence and prevalence of potentially zoonotic enteroparasites in primates of the Cebidae and Callitrichidae families at the Zoológico de Cali from September to November, 2017. Materials and methods: We conducted a prospective cross-sectional study. Serial samples from 50 individuals belonging to seven species and two primate families were analyzed by ova and parasite test, flotation, and Kinyoun stain between September and November, 2017. Results: In order of frequency, the parasite genera found in the seven primate species evaluated were Blastocystis spp., Trichomonas spp., Giardia spp., Entamoeba spp., Strongyloides spp., Cyclospora sp., and Trichuris sp. Conclusions: At least six of the parasite genera found have potential zoonotic implications. It is necessary to establish what are the infection sources at the Zoológico de Cali and implement management protocols to reduce the risk of transmission to both humans and other animals in the collection. Additionally, we offer relevant information on the zoonotic potential of each of the enteroparasites found.

Occurrence and Genetic Diversity of Protist Parasites in Captive Non-Human Primates, Zookeepers, and Free-Living Sympatric Rats in the Córdoba Zoo Conservation Centre, Southern Spain

Little information is currently available on the epidemiology of parasitic and commensal protist species in captive non-human primates (NHP) and their zoonotic potential. This study investigates the occurrence, molecular diversity, and potential transmission dynamics of parasitic and commensal protist species in a zoological garden in southern Spain. The prevalence and genotypes of the main enteric protist species were investigated in faecal samples from NHP (n = 51), zookeepers (n = 19) and free-living rats (n = 64) by molecular (PCR and sequencing) methods between 2018 and 2019. The presence of Leishmania spp. was also investigated in tissues from sympatric rats using PCR. Blastocystis sp. (45.1%), Entamoeba dispar (27.5%), Giardia duodenalis (21.6%), Balantioides coli (3.9%), and Enterocytozoon bieneusi (2.0%) (but not Troglodytella spp.) were detected in NHP. Giardia duodenalis (10.5%) and Blastocystis sp. (10.5%) were identified in zookeepers, while Cryptosporidium spp. (45.3%), G. duodenalis (14.1%), and Blastocystis sp. (6.25%) (but not Leishmania spp.) were detected in rats. Blastocystis ST1, ST3, and ST8 and G. duodenalis sub-assemblage AII were identified in NHP, and Blastocystis ST1 in zookeepers. Giardia duodenalis isolates failed to be genotyped in human samples. In rats, four Cryptosporidium (C. muris, C. ratti, and rat genotypes IV and V), one G. duodenalis (assemblage G), and three Blastocystis (ST4) genetic variants were detected. Our results indicate high exposure of NHP to zoonotic protist species. Zoonotic transmission of Blastocysts ST1 was highly suspected between captive NHP and zookeepers.

Zoonotic assemblages of Giardia duodenalis in captive non-human primates from the largest zoo in Slovakia

Only a few studies based on multilocus characterization have been conducted on the molecular epidemiology of Giardia duodenalis in captive nonhuman primates (NHPs). The present article provides the first report on the occurrence of G. duodenalis in the ring-tailed lemur (Lemur catta) and barbary macaque (Macaca sylvanus) kept in the zoo in Košice, Slovakia. All samples were examined by flotation technique, with total prevalence of 17.4% (4/23). The microscopically positive samples were assayed by nested PCR and consecutively sequenced at β-giardin (bg), glutamate dehydrogenase (gdh) and triosephosphate isomerase (tpi) genes. Positive isolates were recognized as assemblage B and sub-assemblage BIV and subtype WB8 were confirmed. The identification and genotyping of this parasite in Slovakia, may help to better understand the epidemiological situation in Europe about the circulation of G. duodenalis zoonotic assemblages in NHPs.

Occurrence and multilocus genotyping of Giardia duodenalis in captive non-human primates from 12 zoos in China

Giardia duodenalis is a common enteric protozoan that infects a range of hosts including humans and other mammals. Multilocus genotyping of G. duodenalis in captive non-human primates (NHPs) from zoos in China is limited. In this study, we evaluated 302 NHP fecal samples collected from 32 different NHP species. The primates were from 12 zoos distributed across eight provinces and two municipalities (Chongqing and Beijing) of China. The overall infection rate was 8.3% (25/302). The six G. duodenalis-positive zoos and their infection rates were: Suzhou Zoo (40.0%, 4/10), Yangzhou Zoo (22.2%, 2/9), Dalian Zoo (16.7%, 4/24), Chengdu Zoo (12.8%, 6/47), Guiyang Forest Wildlife Zoo (12.1%, 7/58), and Changsha Zoo (4.7%, 2/43). Molecular analysis of three loci, beta-giardin (bg), triose phosphate isomerase (tpi), and glutamate dehydrogenase (gdh), showed high genetic heterogeneity, and seven novel subtypes (BIII-1, MB10-1, WB8-1, B14-1, MB9-1, DN7-1, and BIV-1) were detected within assemblage B. Additional analysis revealed 12 different assemblage B multilocus genotypes (MLGs), one known MLG and 11 novel MLGs. Based on phylogenetic analysis, 12 assemblage B MLGs formed two main clades, MLG-SW (10-12, 18) and MLG-SW (13, 14, 16, 17), the other four MLG-SW (15, 19, 20, 21) were scattered throughout the phylogenetic tree in this study. Using multilocus genotyping, this study expands our understanding of the occurrence of Giardia infection and genetic variation in Giardia in captive non-human primates from zoos in China.

Molecular epidemiology of giardiasis from a veterinary perspective

A total of eight Giardia species are accepted. These include: Giardia duodenalis (syn. Giardia intestinalis and Giardia lamblia), which infects humans and animals, Giardia agilis, Giardia ardeae, Giardia psittaci, Giardia muris, Giardia microti, Giardia peramelis and G. cricetidarum, which infect non-human hosts including amphibians, birds, rodents and marsupials. Giardia duodenalis is a species complex consisting of eight assemblages (A-H), with assemblages A and B the dominant assemblages in humans. Molecular studies to date on the zoonotic potential of Giardia in animals are problematic and are hampered by lack of concordance between loci. Livestock (cattle, sheep, goats and pigs) are predominantly infected with G. duodenalis assemblage E, which has recently been shown to be zoonotic, followed by assemblage A. In cats and dogs, assemblages A, B, C, D and F are commonly reported but relatively few studies have conducted molecular typing of humans and their pets and the results are contradictory with some studies support zoonotic transmission but the majority of studies suggesting separate transmission cycles. Giardia also infects a broad range of wildlife hosts and although much less well studied, host-adapted species as well as G. duodenalis assemblages (A-H) have been identified. Fish and other aquatic wildlife represent a source of infection for humans with Giardia via water contamination and/or consumption of undercooked fish and interestingly, assemblage B and A predominated in the two molecular studies conducted to date. Our current knowledge of the transmission dynamics of Giardia is still poor and the development of more discriminatory typing tools such as whole genome sequencing (WGS) of Giardia isolates is therefore essential.

Intestinal Parasites and the Occurrence of Zoonotic Giardia duodenalis Genotype in Captive Gibbons at Krabokkoo Wildlife Breeding Center, Thailand

Intestinal parasitic infections can have an impact on health and growth of wildlife. The current study aims were to determine the prevalence of intestinal parasites and to molecular characterize Giardia duodenalis and Cryptosporidium spp. in captive gibbons at Krabokkoo Wildlife Breeding Center, Thailand. Fifty-five gibbons, 2 agile- (Hylobates agilis), 38 lar- (Hylobates lar) and 15 pileated gibbons (Hylobates pileatus) were included in this study. Fecal samples were collected individually at Krabokkoo Wildlife Breeding Center, Chachoengsao province, eastern Thailand, in November 2013. Intestinal parasitic infections were examined by zinc sulfate centrifugation flotation and by a commercially available immunofluorescent assay (IFA) for detection of G. duodenalis and Cryptosporidium spp.. Polymerase chain reaction targeting the Giardia glutamate dehydrogenase (gdh), beta- giardin (bg), triose phosphate isomerase (tpi) genes, and the Cryptosporidium small subunit-rRNA and heat-shock protein (hsp70) following by DNA sequencing were performed on the IFA positive samples. The overall prevalence of intestinal parasitic infection in gibbons at Krabokkoo Wildlife Breeding Center was 12.7% (95%CI: 5.3–24.5), Strongyloides spp. eggs or larvae were present in all positive samples. Co-infections with G. duodenalis were detected in 1.8% (95%CI: 0.1–9.7) of the samples. Based on the sequencing results of the three genes, the IFA Giardia positive isolate typed as the zoonotic genotype B. Since the data reveals the occurrence of zoonotic Giardia genotype, good hygiene management is suggested to prevent the transmission of this pathogen from gibbon to human, and vice versa.

Giardia duodenalis in primates: Classification and host specificity based on phylogenetic analysis of sequence data

Giardia duodenalis colonizes the gastrointestinal tract of a wide range of hosts, including humans and other primates. It is grouped into eight different Assemblages and, beyond that, into a number of sub-Assemblages, defined ad hoc on the basis of genetic differences; these various groups are often considered to be associated with a specific restricted host range. The aim of this study was to use publicly available genotyping data to investigate the relatedness of human and non-human primate (NHP) Giardia isolates in order to evaluate the usefulness of current taxonomic classification and to assess whether there is potential for zoonotic transmission between humans and NHP. Our final data set consisted of sequence data from 165 isolates, 111 from NHP and 54 from humans. Assemblages were well defined, but sub-Assemblages across Assemblage B were not resolved. Although sub-Assemblages AI and AII were resolved, the terms were not found to capture any useful molecular or host/deme properties. In the phylogenetic tree, NHP isolates were scattered among human isolates across Assemblages A and B, and were even found in Assemblage E. We conclude that there does not appear to be significant molecular distinction between human and NHP Giardia isolates across these four molecular markers. Thus, on the basis of these markers, we cannot exclude a risk for zoonotic and anthropozoonotic transmission of Assemblages A and B isolates, irrespective of sub-Assemblage classification. We further evaluated the relative merit of the four genes used in genotyping studies. The tpi, gdh and bg genes gave relatively congruent tree topologies, but the SSU gene did not resolve Assemblages according to the current classification. Future genotyping efforts should aim for multilocus or whole-genome approaches and, in particular, use of the SSU gene as the sole marker should be avoided when possible.

Genetic variability and transcontinental sharing of Giardia duodenalis infrapopulations determined by glutamate dehydrogenase gene

Microevolutionary data of Giardia duodenalis sub-assemblages is a prerequisite for determining the invasion zoonotic patterns of the parasite. To infer transmission patterns that could not be differentiated by the phenotypic features, a population genetic investigation is crucial for the elucidation of the genetic structure of G. duodenalis among the continents. Forty G. duodenalis positive fecal samples were collected from different foci of Northwest Iran. The specimens were subjected to Trichrome staining and sucrose gradient flotation. DNA samples were extracted, amplified, and sequenced by targeting glutamate dehydrogenase (gdh) gene. The global gdh sequences of sub-assemblages AII and BIV retrieved from NCBI GenBank were analyzed to estimate diversity indices, neutrality indices, and gene migration tests. Sequencing analyses indicated various levels of genetic variability of sub-assemblages AII and BIV among the five continents. Sub-assemblage BIV had greater genetic variability (haplotype diversity: 0.975; nucleotide diversity: 0.04246) than sub-assemblage AII. The statistical Fst value demonstrated that the genetic structure of sub-assemblages AII and BIV are moderately differentiated between European-American populations (Fst: 0.05352-0.15182), whereas a significant differentiation was not seen among other geographical population pairs. We conclude that a high gene flow of G. duodenalis sub-assemblages AII and BIV is unequivocally sharing among the continents. The current findings strengthen our knowledge to assess the evolutionary patterns of G. duodenalis in endemic foci of the world and it will become the basis of public health policy to control human giardiasis.

Molecular characterisation of protist parasites in human-habituated mountain gorillas (Gorilla beringei beringei), humans and livestock, from Bwindi impenetrable National Park, Uganda

Background

Over 60 % of human emerging infectious diseases are zoonotic, and there is growing evidence of the zooanthroponotic transmission of diseases from humans to livestock and wildlife species, with major implications for public health, economics, and conservation. Zooanthroponoses are of relevance to critically endangered species; amongst these is the mountain gorilla (Gorilla beringei beringei) of Uganda. Here, we assess the occurrence of Cryptosporidium, Cyclospora, Giardia, and Entamoeba infecting mountain gorillas in the Bwindi Impenetrable National Park (BINP), Uganda, using molecular methods. We also assess the occurrence of these parasites in humans and livestock species living in overlapping/adjacent geographical regions.

Results

Diagnostic PCR detected Cryptosporidium parvum in one sample from a mountain gorilla (IIdA23G2) and one from a goat (based on SSU). Cryptosporidium was not detected in humans or cattle. Cyclospora was not detected in any of the samples analysed. Giardia was identified in three human and two cattle samples, which were linked to assemblage A, B and E of G. duodenalis. Sequences defined as belonging to the genus Entamoeba were identified in all host groups. Of the 86 sequence types characterised, one, seven and two have been recorded previously to represent genotypes of Cryptosporidium, Giardia, and Entamoeba, respectively, from humans, other mammals, and water sources globally.

Conclusions

This study provides a snapshot of the occurrence and genetic make-up of selected protists in mammals in and around BINP. The genetic analyses indicated that 54.6% of the 203 samples analysed contained parasites that matched species, genotypes, or genetic assemblages found globally. Seventy-six new sequence records were identified here for the first time. As nothing is known about the zoonotic/zooanthroponotic potential of the corresponding parasites, future work should focus on wider epidemiological investigations together with continued surveillance of all parasites in humans, other mammals, the environment, and water in this highly impoverished area.

Electronic supplementary material

The online version of this article (doi:10.1186/s13071-017-2283-5) contains supplementary material, which is available to authorized users.

Occurrence and molecular genotyping of Giardia duodenalis and Cryptosporidium spp. in wild mesocarnivores in Spain

There is a surprisingly scarce amount of epidemiological and molecular data on the prevalence, frequency, and diversity of the intestinal protozoan parasites Giardia duodenalis and Cryptosporidium spp. in wildlife in general and mesocarnivore species in particular. Consequently, the extent of the cyst/oocyst environmental contamination attributable to these wild host species and their potential implications for public veterinary health remain largely unknown. In this molecular epidemiological survey a total of 193 individual faecal samples from badgers (Meles meles, n=70), ferrets (Mustela putorius furo, n=2), genets (Genetta genetta, n=6), Iberian lynxes (Lynx pardinus, n=6), beech martens (Martes foina, n=8), mongooses (Herpestes ichneumon, n=2), otters (Lutra lutra, n=2), polecats (Mustela putorius, n=2), red foxes (Vulpes vulpes, n=87), wildcats (Felis silvestris, n=2), and wolves (Canis lupus, n=6) were obtained from road-killed, hunted, and accidentally found carcasses, and from camera-trap surveys or animals entering rescue shelters, during the period December 2003-April 2016. Investigated specimens were collected in five Spanish autonomous regions including Andalusia (n=1), Asturias (n=69), Basque Country (n=49), Castile-La Mancha (n=38), and Extremadura (n=36). The presence of cysts/oocysts was confirmed by PCR-based methods targeting the small subunit (ssu) ribosomal RNA gene of these parasite species. Genotyping of the obtained isolates were attempted at appropriate markers including the glutamate dehydrogenase (G. duodenalis) and the 60-kDa glycoprotein (C. parvum and C. ubiquitum) loci. Overall, G. duodenalis was detected in 8% (7/87) of red foxes, a single beech marten, and a single wolf, respectively. Cryptosporidium was identified in 3% (2/70) of badgers, 8% (7/87) of red foxes, a single genet, and a single mongoose, respectively. None of the nine G. duodenalis isolates generated could be genotyped at the assemblage/sub-assemblage level. Out of the nine Cryptosporidium isolates successfully characterized, three were identified as C. canis (one in a mongoose and two in red foxes), and three as C. parvum (one in a badger and three in red foxes). The remaining three isolates were assigned to C. felis (in a red fox), C. hominis (in a badger), and C. ubiquitum (in a red fox), respectively. Two additional Cryptosporidium isolates infecting a badger and a genet, respectively, were untypable. The red fox was confirmed as a suitable host of potentially zoonotic Cryptosporidium species, mainly C. parvum and C. ubiquitum. The high mobility and wide home range of red foxes, together with their increasing presence in urban and peri-urban settings, may led to the overlapping of sylvatic and domestic cycles of the parasite, and consequently, to an increased risk of cryptosporidiosis in production animals and humans. The detection of C. hominis oocysts in a badger raises the question of whether this finding represents a true infection or a sporadic event of mechanical passage of C. hominis oocyst of anthroponotic origin.

First report of zoonotic Cryptosporidium spp., Giardia intestinalis and Enterocytozoon bieneusi in golden takins (Budorcas taxicolor bedfordi)

Genetic study of Cryptosporidium spp., Giardia intestinalis and Enterocytozoon bieneusi at species/assemblage/genotype/subtype level facilitates understanding their mechanical transmissions and underpins their control. A total of 191 fresh faecal samples were collected from golden takins in China and examined using multilocus sequence typing (MLST). Cryptosporidium spp. was detected in 15 faecal samples (7.9%), including Cryptosporidium parvum (2/15) and Cryptosporidium andersoni (13/15). MLST tool identified C. andersoni subtypes (A1, A4, A4, A1) and (A4, A4, A4, A1), and C. parvum gp60 gene subtype IId A19G1. The prevalence of G. intestinalis infection was 8.9% (17/191) and assemblage analysis identified 14 assemblage E and three assemblage B. Intra-variations were observed at triose phosphate isomerase (tpi), beta giardin (bg) and glutamate dehydrogenase (gdh) loci within the assemblage E, showing seven, three and three new subtypes in respective locus. Ten and one multilocus genotypes (MLGs) were present in assemblages E and B, respectively. E. bieneusi infection was positive in 14.7% (28/191) of the examined specimens, with three genotypes known (BEB6, D and I) and four novel internal transcribed spacer (ITS) genotypes (TEB1-TEB4). The present study revealed, for the first time, the presence of zoonotic C. parvum IId A19G1, G. intestinalis assemblage B and E. bieneusi genotype D and four novel genotypes in golden takins in China. These findings expand the host range of three zoonotic pathogens and have important implications for controlling cryptosporidiosis, giardiasis and microsporidiosis in humans and animals.

Prevalence and molecular characterization of Cryptosporidium spp. and Giardia duodenalis in diarrhoeic patients in the Qikiqtani Region, Nunavut, Canada

Background

Although the prevalences of infection with the protozoan parasites Cryptosporidium spp. and Giardia duodenalis in humans appear to be relatively high in the Canadian North, their transmission patterns are poorly understood.

Objective

To determine the detection rate and the molecular characteristics of Cryptosporidium spp. and Giardia duodenalis in diarrhoeic patients in the Qikiqtani (Baffin Island) Region of Nunavut, Canada, in order to better understand the burden of illness and the potential mechanisms of transmission.

Study design/methods

Diarrhoeal stool specimens (n=108) submitted to the Qikiqtani General Hospital for clinical testing were also tested for the presence of Cryptosporidium spp. and Giardia duodenalis using epifluorescence microscopy and polymerase chain reaction (PCR). DNA sequencing and restriction fragment length polymorphism (RFLP) analyses were performed on PCR-positive specimens to determine the species, genotypes and sub-genotypes of the parasites.

Results

Cryptosporidium was detected in 15.7% of the diarrhoeic patients, while Giardia was detected in 4.6%. DNA sequencing of a fragment of the small subunit rRNA gene indicated that all of the Cryptosporidium amplicons had a 100% homology to C. parvum, and a gp60 assay showed that all aligned with C. parvum sub-genotype IIa. Microsatellite analysis revealed 3 cases of sub-genotype IIaA15G2R1, 2 of IIaA15G1R and 1 case each of sub-genotypes IIaA16G1R1 and IIaA15R1. For Giardia, results based on the amplification of both the 16S rRNA gene and the gdh gene were generally in agreement, and both DNA sequencing and RFLP demonstrated the presence of the G. duodenalis Assemblage B genotype.

Conclusions

Both C. parvum and G. duodenalis Assemblage B were present in human diarrhoeal stool specimens from Nunavut, which was suggestive of zoonotic transmission, although human-to-human transmission cannot be ruled out. To fully understand the public health significance of the different Cryptosporidium and Giardia species and genotypes in diarrhoeic patients, it will be imperative to establish the extent of genetic diversity within these parasites through comprehensive studies of the molecular epidemiology of cryptosporidiosis and giardiasis in the Nunavut region.

Multi-locus analysis of Giardia duodenalis from nonhuman primates kept in zoos in China: geographical segregation and host-adaptation of assemblage B isolates

Only a few studies based on single locus characterization have been conducted on the molecular epidemiology of Giardia duodenalis in nonhuman primates (NHPs). The present study was conducted to examine the occurrence and genotype identity of G. duodenalis in NHPs based on multi-locus analysis of the small-subunit ribosomal RNA (SSU rRNA), triose phosphate isomerase (tpi), glutamate dehydrogenase (gdh), and beta-giardin (bg) genes. Fecal specimens were collected from 496 animals of 36 NHP species kept in seven zoos in China and screened for G. duodenalis by tpi-based PCR. G. duodenalis was detected in 92 (18.6%) specimens from 18 NHP species, belonging to assemblage A (n=4) and B (n=88). In positive NHP species, the infection rates ranged from 4.8% to 100%. In tpi sequence analysis, the assemblage A included subtypes A1, A2 and one novel subtype. Multi-locus analysis of the tpi, gdh, and bg genes detected 11 (8 known and 3 new), 6 (3 known and 3 new) and 9 (2 known and 7 new) subtypes in 88, 47 and 35 isolates in assemblage B, respectively. Thirty-two assemblage B isolates with data at all three loci yielded 15 multi-locus genotypes (MLGs), including 2 known and 13 new MLGs. Phylogenetic analysis of concatenated sequences of assemblage B showed that MLGs found here were genetically different from those of humans, NHPs, rabbit and guinea pig in Italy and Sweden. It further indicated that assemblage B isolates in ring-tailed lemurs and squirrel monkeys might be genetically different from those in other NHPs. These data suggest that NHPs are mainly infected with G. duodenalis assemblage B and there might be geographical segregation and host-adaptation in assemblage B in NHPs.

Multilocus typing of Cryptosporidium spp. and Giardia duodenalis from non-human primates in China

Non-human primates (NHPs) are commonly infected with Cryptosporidium spp. and Giardia duodenalis. However, molecular characterisation of these pathogens from NHPs remains scarce. In this study, 2,660 specimens from 26 NHP species in China were examined and characterised by PCR amplification of 18S rRNA, 70kDa heat shock protein (hsp70) and 60kDa glycoprotein (gp60) gene loci for Cryptosporidium; and 1,386 of the specimens by ssrRNA, triosephosphate isomerase (tpi) and glutamate dehydrogenase (gdh) gene loci for Giardia. Cryptosporidium was detected in 0.7% (19/2660) specimens of four NHP species including rhesus macaques (0.7%), cynomolgus monkeys (1.0%), slow lorises (10.0%) and Francois' leaf monkeys (6.7%), belonging to Cryptosporidium hominis (14/19) and Cryptosporidium muris (5/19). Two C. hominis gp60 subtypes, IbA12G3 and IiA17 were observed. Based on the tpi locus, G. duodenalis was identified in 2.2% (30/1,386) of specimens including 2.1% in rhesus macaques, 33.3% in Japanese macaques, 16.7% in Assam macaques, 0.7% in white-headed langurs, 1.6% in cynomolgus monkeys and 16.7% in olive baboons. Sequence analysis of the three targets indicated that all of the Giardia-positive specimens belonged to the zoonotic assemblage B. Highest sequence polymorphism was observed at the tpi locus, including 11 subtypes: three known and eight new ones. Phylogenetic analysis of the subtypes showed that most of them were close to the so-called subtype BIV. Intragenotypic variations at the gdh locus revealed six types of sequences (three known and three new), all of which belonged to so-called subtype BIV. Three specimens had co-infection with C. hominis (IbA12G3) and G. duodenalis (BIV). The presence of zoonotic genotypes and subtypes of Cryptosporidium spp. and G. duodenalis in NHPs suggests that these animals can potentially contribute to the transmission of human cryptosporidiosis and giardiasis.

Molecular typing of Giardia duodenalis isolates from nonhuman primates housed IN a Brazilian zoo

Giardia infections in captive nonhuman primates (NHP) housed at a Brazilian zoo were investigated in order to address their zoonotic potential. Fresh fecal samples were collected from the floors of 22 enclosures where 47 primates of 18 different species were housed. The diagnosis of intestinal parasites after concentration by sedimentation and flotation methods revealed the following parasites and their frequencies: Giardia (18%); Entamoeba spp. (18%); Endolimax nana (4.5%); Iodamoeba spp. (4.5%); Oxyurid (4.5%) and Strongylid (4.5%). Genomic DNA extracted from all samples was processed by PCR methods in order to amplify fragments of gdh and tpi genes of Giardia. Amplicons were obtained from samples of Ateles belzebuth, Alouatta caraya, Alouatta fusca and Alouatta seniculus. Clear sequences were only obtained for the isolates from Ateles belzebuth (BA1), Alouatta fusca (BA2) and Alouatta caraya (BA3). According to the phenetic analyses of these sequences, all were classified as assemblage A. For the tpi gene, all three isolates were grouped into sub-assemblage AII (BA1, BA2 and BA3) whereas for the gdh gene, only BA3 was sub-assemblage AII, and the BA1 and BA2 were sub-assemblage AI. Considering the zoonotic potential of the assemblage A, and that the animals of the present study show no clinical signs of infection, the data obtained here stresses that regular coproparasitological surveys are necessary to implement preventive measures and safeguard the health of the captive animals, of their caretakers and of people visiting the zoological gardens.

Zoonotic potential of Giardia

Giardia duodenalis (syn. Giardia lamblia and Giardia intestinalis) is a common intestinal parasite of humans and mammals worldwide. Assessing the zoonotic transmission of the infection requires molecular characterization as there is considerable genetic variation within G. duodenalis. To date eight major genetic groups (assemblages) have been identified, two of which (A and B) are found in both humans and animals, whereas the remaining six (C to H) are host-specific and do not infect humans. Sequence-based surveys of single loci have identified a number of genetic variants (genotypes) within assemblages A and B in animal species, some of which may have zoonotic potential. Multi-locus typing data, however, has shown that in most cases, animals do not share identical multi-locus types with humans. Furthermore, interpretation of genotyping data is complicated by the presence of multiple alleles that generate "double peaks" in sequencing files from PCR products, and by the potential exchange of genetic material among isolates, which may account for the non-concordance in the assignment of isolates to specific assemblages. Therefore, a better understanding of the genetics of this parasite is required to allow the design of more sensitive and variable subtyping tools, that in turn may help unravel the complex epidemiology of this infection.

Population-based analyses of Giardia duodenalis is consistent with the clonal assemblage structure

Background

Giardia duodenalis is a common protozoan parasite of humans and animals. Genetic characterization of single loci indicates the existence of eight groups called assemblages, which differ in their host distribution. Molecular analyses challenged the idea that G. duodenalis is a strictly clonal diplomonad by providing evidence of recombination within and between assemblages. Particularly, inter-assemblage recombination events would complicate the interpretation of multi-locus genotyping data from field isolates: where is a host infected with multiple Giardia genotypes or with a single, recombined Giardia genotype.

Methods

Population genetic analyses on the single and multiple-locus level on an extensive dataset of G. duodenalis isolates from humans and animals were performed.

Results

Our analyses indicate that recombination between isolates from different assemblages are apparently very rare or absent in the natural population of Giardia duodenalis. At the multi-locus level, our statistical analyses are more congruent with clonal reproduction and can equally well be explained with the presence of multiple G. duodenalis genotypes within one field isolate.

Conclusions

We conclude that recombination between G. duodenalis assemblages is either very rare or absent. Recombination between genotypes from the same assemblage and genetic exchange between the nuclei of a single cyst needs further investigation.

Enteric protozoa in the developed world: a public health perspective

Several enteric protozoa cause severe morbidity and mortality in both humans and animals worldwide. In developed settings, enteric protozoa are often ignored as a cause of diarrheal illness due to better hygiene conditions, and as such, very little effort is used toward laboratory diagnosis. Although these protozoa contribute to the high burden of infectious diseases, estimates of their true prevalence are sometimes affected by the lack of sensitive diagnostic techniques to detect them in clinical and environmental specimens. Despite recent advances in the epidemiology, molecular biology, and treatment of protozoan illnesses, gaps in knowledge still exist, requiring further research. There is evidence that climate-related changes will contribute to their burden due to displacement of ecosystems and human and animal populations, increases in atmospheric temperature, flooding and other environmental conditions suitable for transmission, and the need for the reuse of alternative water sources to meet growing population needs. This review discusses the common enteric protozoa from a public health perspective, highlighting their epidemiology, modes of transmission, prevention, and control. It also discusses the potential impact of climate changes on their epidemiology and the issues surrounding waterborne transmission and suggests a multidisciplinary approach to their prevention and control.

Giardia--from genome to proteome

In this review, the current status of genomic and proteomic research on Giardia is examined in terms of evolutionary biology, phylogenetic relationships and taxonomy. The review also describes how characterising genetic variation in Giardia from numerous hosts and endemic areas has provided a better understanding of life cycle patterns, transmission and the epidemiology of Giardia infections in humans, domestic animals and wildlife. Some progress has been made in relating genomic information to the phenotype of Giardia, and as a consequence, new information has been obtained on aspects of developmental biology and the host-parasite relationship. However, deficiencies remain in our understanding of pathogenesis and host specificity, highlighting the limitations of currently available genomic datasets.