First detection and genetic characterisation of Enterocytozoon bieneusi in wild deer in Melbourne's water catchments in Australia

First molecular detection and characterization of Enterocytozoon bieneusi different genotypes in human patients from Italy

Enterocytozoon bieneusi is one of the 17 microsporidian species pathogenic to humans in low and high-income countries, inducing both symptomatic and asymptomatic intestinal infections, independently of the immunological condition of the infected individual. Faecal-oral transmission occurs in a broad hosts range, including several animal species, but the parasite's zoonotic potential remains still unclear. Few studies are available in Italy regarding E. bieneusi presence in humans and no data on its genetic variability are so far reported. In this investigation, through the ITSr RNA sequences analysis, we provided the first E. bieneusi molecular characterization from symptomatic patients in Italy. Faecal samples from 410 patients sent for routine analyses to the Unit of Parasitology, Policlinico Tor Vergata, Rome, and resulted positive for E. bieneusi to a cartridge-based molecular test for qualitative detection (Novodiag® Stool Parasites assay), were collected. DNA was extracted, endpoint PCR performed and then sequences obtained for 3/410 patients (0.7 %). Genotype A (N = 1), genotype C (N = 1) and genotype K (N = 1) were identified, all belonging to phylogenetic Group 1. One patient (identified as genotype A) showed positivity to the same genotype previously characterized after a two-month period. Additional investigations are required, within a One Health framework, to review the importance of a zoonotic potential linked to E. bieneusi in human populations, animals and environmental reservoirs worldwide.

Occurrence and Genetic Diversity of the Zoonotic Enteric Protozoans and Enterocytozoon bieneusi in Père David's Deer (Elaphurus davidianus) from Beijing, China

Cryptosporidium spp., Blastocystis, Giardia duodenalis, Balantioides coli, Pentatrichomonas hominis, and Enterocytozoon bieneusi are enteric protozoan parasites and fungal species in humans and animals. Père David's deer is an endangered species in China, but the prevalence of enteric protozoans in this species still needs to be further studied. Thus, we investigated the prevalence and genetic diversity of zoonotic parasites in Père David's deer during the period of 2018-2021. Among the 286 fecal samples collected from Père David's deer in the Nanhaizi Nature Reserve, 83 (29.0%) were positive for Blastocystis, 70 (24.5%) were positive for E. bieneusi, while other protozoan parasites were negative. Based on a phylogenetic analysis, three Blastocystis subtypes (ST10, ST14, and ST21) and ten E. bieneusi genotypes (Genotype D, MWC_d1, HLJD-V, Peru6, BEB6, BJED-I to BJED-I V) were identified. In addition, the Blastocystis subtype ST14 and the E. bieneusi genotype D and Peru6 were first detected in Père David's deer. Our study first reports the presence of two enteric protozoans in Père David's deer during a 4-year active surveillance and provides more information about zoonotic subtypes/genotypes of Blastocystis and E. bieneusi in deer.

Epidemiological-clinical profile and mortality in patients coinfected with Trypanosoma cruzi/HIV: experience from a Brazilian reference center

BACKGROUND

The recent urbanization of Chagas disease (CD) has contributed to a greater risk of coexistence with human immunodeficiency virus (HIV) and AIDS.

METHODS

This retrospective observational study included patients who were followed at INI-Fiocruz between July 1986 and October 2021. All patients underwent an assessment protocol that included sociodemographic profile, epidemiological history, and clinical evaluation. Descriptive data analyses included reports of the medians and frequencies of variables of interest. Differences in medians between groups were tested using the Mann-Whitney U test. Differences in frequency were tested using Fisher's exact test.

RESULTS

Among 2201 patients, 11 (0.5%) were identified with Trypanosoma cruzi/HIV coinfection. Of these, 63.6% were women with a median age of 51.0 years old. Two patients had the indeterminate form of CD, six had the cardiac form, two had the digestive form and one had the cardio-digestive form. Half of the patients were undergoing antiretroviral treatment at the time of coinfection diagnosis with a median CD4+ count of 350 cells/μL and a viral load of 1500 copies/μL. Four patients underwent a xenodiagnosis test at coinfection diagnosis, which all yielded positive results; two of them presented high parasitemia under the risk of reactivation. Prophylaxis for CD reactivation was administered to four patients; two with ketoconazole and two with benznidazole. Six patients died after a median follow-up of 22.5 months, with AIDS being the most common cause of death. Only one case of reactivation was observed.

CONCLUSIONS

Early diagnosis and prompt treatment of CD reactivation dramatically reduced mortality. Identification of Trypanosoma cruzi/HIV co-infection is crucial to planning a close follow-up of coinfected patients.

Zoonotic Enterocytozoon bieneusi genotypes in free-ranging and farmed wild ungulates in Spain

Microsporidia comprises a diverse group of obligate, intracellular, and spore-forming parasites that infect a wide range of animals. Among them, Enterocytozoon bieneusi is the most frequently reported species in humans and other mammals and birds. Data on the epidemiology of E. bieneusi in wildlife is limited. Hence, E. bieneusi was investigated in eight wild ungulate species present in Spain (genera Ammotragus, Capra, Capreolus, Cervus, Dama, Ovis, Rupicapra, and Sus) by molecular methods. Faecal samples were collected from free-ranging (n = 1058) and farmed (n = 324) wild ungulates from five Spanish bioregions. The parasite was detected only in red deer (10.4%, 68/653) and wild boar (0.8%, 3/359). Enterocytozoon bieneusi infections were more common in farmed (19.4%, 63/324) than in wild (1.5%, 5/329) red deer. Eleven genotypes were identified in red deer, eight known (BEB6, BEB17, EbCar2, HLJD-V, MWC_d1, S5, Type IV, and Wildboar3) and three novel (DeerSpEb1, DeerSpEb2, and DeerSpEb3) genotypes. Mixed genotype infections were detected in 15.9% of farmed red deer. Two genotypes were identified in wild boar, a known (Wildboar3) and a novel (WildboarSpEb1) genotypes. All genotypes identified belonged to E. bieneusi zoonotic Groups 1 and 2. This study provides the most comprehensive epidemiological study of E. bieneusi in Spanish ungulates to date, representing the first evidence of the parasite in wild red deer populations worldwide. Spanish wild boars and red deer are reservoir of zoonotic genotypes of E. bieneusi and might play an underestimated role in the transmission of this microsporidian species to humans and other animals.

Molecular detection and characterization of Enterocytozoon bieneusi in captive alpine musk deer (Moschus chrysogaster) in Central and Eastern of Gansu Province, China

The most ubiquitously diagnosed microsporidian species in animals and humans is Enterocytozoon bieneusi (E. bieneusi). In this case, this work aimed to probe the occurrence and genotypes of this pathogen in captive alpine musk deer (Moschus chrysogaster) in Gansu Province, China. After fecal sample collection (n = 201) from three farms in Gansu, the internal transcribed spacer (ITS) region of the rRNA gene was probed by PCR for detection and genotyping of E. bieneusi. The infection rate of E. bieneusi in alpine musk deer was 6.0% (12/201), with 0% (0/36), 7.7% (5/65) and 7.0% (7/100) in farms 1 to 3, respectively. The infection rate of E. bieneusi in young alpine musk deer (3.2%; 1/31) is lower than that of adults (6.5%; 11/170), with no evident significant differences between age groups (P > 0.05). Three known genotypes D (n = 8), EbpA (n = 3) and BEB6 (n = 1) were identified by sequence analysis. This is the first such scrutiny of E. bieneusi infection in alpine musk deer in China as per our knowledge. Genotypes D and EbpA were common in humans and animals that is suggestive of the plausible zoonotic role in E. bieneusi transmission by alpine musk deer.

Molecular Epidemiology and Genetic Diversity of Enterocytozoon bieneusi in Cervids from Milu Park in Beijing, China

Simple Summary

Enterocytozoon bieneusi is the most prevalent microsporidian species that can cause significant intestinal diseases in both humans and animals worldwide. This study investigated the overall E. bieneusi prevalence of 21.9% (47/215) in captive and free-ranging deer species in Beijing, China. Thirteen E. bieneusi genotypes including six known and seven novel genotypes were identified. These resources will provide the insights to understand the veterinary and public health and the transmission dynamics between animal environments and human ones.

Abstract

Enterocytozoon bieneusi is the most prevalent microsporidian species that can cause zoonotic diseases in humans and animals. Despite receiving increasing attention in relation to domestic animals, there has been limited information on the infection burden of E. bieneusi in cervids. Altogether, 215 fecal samples collected from four deer species in Beijing, China were examined by nested- Polymerase Chain Reaction (PCR)targeting the internal transcribed spacer (ITS) region. The overall prevalence of E. bieneusi in deer was 21.9% (47/215), with 30.0% (24/80) in Pere David’s deer, 27.3% (15/55) in fallow deer, 12.5% (5/40) in sika deer, and 7.5% (3/40) in Chinese water deer. Thirteen E. bieneusi genotypes were identified, including six known (HLJD-V, MWC_d1, BEB6, CGC2, JLD-XV, and HND-I) and seven novel genotypes (BJED-I to BJED-V, BJFD, and BJCWD). A phylogenetic analysis showed that 38.3% of the isolates belonged to zoonotic Group 1. In addition, E. bieneusi infection was first detected in fallow deer and Chinese water deer, which could act as potential zoonotic reservoirs. Our findings suggest that E. bieneusi circulates in deer and might be of importance to public health.

Chronic Infections in Mammals Due to Microsporidia

Microsporidia are pathogenic organism related to fungi. They cause infections in a wide variety of mammals as well as in avian, amphibian, and reptilian hosts. Many microsporidia species play an important role in the development of serious diseases that have significant implications in human and veterinary medicine. While microsporidia were originally considered to be opportunistic pathogens in humans, it is now understood that infections also occur in immune competent humans. Encephalitozoon cuniculi, Encephalitozoon intestinalis, and Enterocytozoon bieneusi are primarily mammalian pathogens. However, many other species of microsporidia that have some other primary host that is not a mammal have been reported to cause sporadic mammalian infections. Experimental models and observations in natural infections have demonstrated that microsporidia can cause a latent infection in mammalian hosts. This chapter reviews the published studies on mammalian microsporidiosis and the data on chronic infections due to these enigmatic pathogens.

Wildlife Is a Potential Source of Human Infections of Enterocytozoon bieneusi and Giardia duodenalis in Southeastern China

Wildlife is known to be a source of high-impact pathogens affecting people. However, the distribution, genetic diversity, and zoonotic potential of Cryptosporidium, Enterocytozoon bieneusi, and Giardia duodenalis in wildlife are poorly understood. Here, we conducted the first molecular epidemiological investigation of these three pathogens in wildlife in Zhejiang and Shanghai, China. Genomic DNAs were derived from 182 individual fecal samples from wildlife and then subjected to a nested polymerase chain reaction–based sequencing approach for detection and characterization. Altogether, 3 (1.6%), 21 (11.5%), and 48 (26.4%) specimens tested positive for Cryptosporidium species, E. bieneusi, and G. duodenalis, respectively. Sequence analyses revealed five known (BEB6, D, MJ13, SC02, and type IV) and two novel (designated SH_ch1 and SH_deer1) genotypes of E. bieneusi. Phylogenetically, novel E. bieneusi genotype SH_deer1 fell into group 6, and the other genotypes were assigned to group 1 with zoonotic potential. Three novel Cryptosporidium genotypes (Cryptosporidium avian genotype V-like and C. galli-like 1 and 2) were identified, C. galli-like 1 and 2 formed a clade that was distinct from Cryptosporidium species. The genetic distinctiveness of these two novel genotypes suggests that they represent a new species of Cryptosporidium. Zoonotic assemblage A (n = 36) and host-adapted assemblages C (n = 1) and E (n = 7) of G. duodenalis were characterized. The overall results suggest that wildlife act as host reservoirs carrying zoonotic E. bieneusi and G. duodenalis, potentially enabling transmission from wildlife to humans and other animals.

FIRST REPORT OF ENTEROCYTOZOON BIENEUSI FROM AN AFRICAN LION (PANTHERA LEO) IN A ZOO IN THE REPUBLIC OF KOREA

Enterocytozoon bieneusi is the most common species of microsporidia that infects humans and animals worldwide. However, no information is available on E. bieneusi infection among zoo animals in the Republic of Korea (ROK). Here, we investigated the prevalence of E. bieneusi among animals kept in zoos and the zoonotic potential of the E. bieneusi identified. E. bieneusi was detected only in one African lion (Panthera leo) with diarrhea, using PCR and sequencing analysis of the internal transcribed spacer (ITS) of the rRNA gene. A phylogenetic analysis based on the ITS gene showed that the lion isolate was classified into a novel genotype KPL belonging to Group 2. The KPL genotype identified in this study differed from genotype I in 6 nucleotides and from genotype I-like in 3 nucleotides, respectively, indicating that Group 2 has the capacity to infect a wide range of hosts. This is the first report of the presence of E. bieneusi in an African lion housed in a zoo in the ROK. Further investigation is necessary to study E. bieneusi infection among zoo animals in various regions and to determine the transmission route, in order to control E. bieneusi infection.

Enterocytozoon bieneusi of animals-With an 'Australian twist'

Enterocytozoon bieneusi is a microsporidian microorganism that causes intestinal disease in animals including humans. E. bieneusi is an obligate intracellular pathogen, typically causing severe or chronic diarrhoea, malabsorption and/or wasting. Currently, E. bieneusi is recognised as a fungus, although its exact classification remains contentious. The transmission of E. bieneusi can occur from person to person and/or animals to people. Transmission is usually via the faecal-oral route through E. bieneusi spore-contaminated water, environment or food, or direct contact with infected individuals. Enterocytozoon bieneusi genotypes are usually identified and classified by PCR-based sequencing of the internal transcribed spacer region (ITS) of nuclear ribosomal DNA. To date, ~600 distinct genotypes of E. bieneusi have been recorded in ~170 species of animals, including various orders of mammals and reptiles as well as insects in >40 countries. Moreover, E. bieneusi has also been found in recreational water, irrigation water, and treated raw- and waste-waters. Although many studies have been conducted on the epidemiology of E. bieneusi, prevalence surveys of animals and humans are scant in some countries, such as Australia, and transmission routes of individual genotypes and related risk factors are poorly understood. This article/chapter reviews aspects of the taxonomy, biology and epidemiology of E. bieneusi; the diagnosis, treatment and prevention of microsporidiosis; critically appraises the naming system for E. bieneusi genotypes as well as the phylogenetic relationships of these genotypes; provides new insights into the prevalence and genetic composition of E. bieneusi populations in animals in parts of Australia using molecular epidemiological tools; and proposes some areas for future research in the E. bieneusi/microsporidiosis field.

Ecological and public health significance of Enterocytozoon bieneusi

Enterocytozoon bieneusi, a fungus-like protist parasite, causes symptomatic and asymptomatic intestinal infections in terrestrial animals and is also abundant in the environment. This parasite has been isolated from a variety of host types including humans, livestock, companion animals, birds, and wildlife, as well as the natural and urban environments including drinking source water, coastal water, recreational water, wastewater, vegetables in retail markets, and raw milk on farms. E. bieneusi exhibits high genetic diversity among host species and environmental sources and at least 500 genotypes have been identified thus far. Since its discovery in AIDS patients in 1985, scientists across the world have worked to demonstrate the natural history and public health potential of this pathogen. Here we review molecular typing studies on E. bieneusi and summarize relevant data to identify the potential sources of human and nonhuman infections and environmental contamination. This review also discusses the possible transmission routes of E. bieneusi and the associated risk factors, and advocates the importance of the One Health approach to tackle E. bieneusi infections.

Detection of Intestinal Parasites and Genetic Characterization of Enterocytozoon bieneusi in Hedgehogs from China

Microsporidia are a group of unicellular and opportunistic intestinal parasites in which Enterocytozoon bieneusi is a frequent species causing microsporidial infections in humans. Many domesticated and wild animals have been shown to be hosts of E. bieneusi and other microsporidia. The role of hedgehogs in the ecology of microsporidia is unclear; therefore, we investigated the prevalence and genetic diversity of E. bieneusi, Cryptosporidium, and Blastocystis spp. in hedgehogs (Erinaceus amurensis) collected from Hubei Province in Central China. PCR amplification of the internal transcribed spacer region of the ribosomal DNA indicated that 9.8% (4/41) hedgehogs were positive to E. bieneusi, but none (0/41) was positive to Cryptosporidium and Blastocystis spp. Phylogenetic analysis showed the strains detected from the hedgehogs belong to four novel genotypes (EA1-EA4), which were most closely related to type IV of group 1c. This study demonstrated that hedgehogs are hosts of E. bieneusi and may play a role in the transmission of E. bieneusi to humans in the process of being caught and slaughtered.

Enterocytozoon bieneusi genotypes in farmed goats and sheep in Ningxia, China

Enterocytozoon bieneusi is reported to be a common microsporidian of humans and animals in various countries. However, scarce information on E. bieneusi has been recorded in farmed goats and sheep in China. As such, we undertook molecular epidemiological investigation of E. bieneusi in farmed goats (Capra aegagrus hircus) and sheep (Ovis aries) in Ningxia, China. A total of 660 genomic DNAs were extracted from individual faecal samples from famed goats (n = 300) and sheep (n = 360), and then tested using a nested PCR-based sequencing approach employing internal transcribed spacer (ITS) of nuclear ribosomal DNA as the genetic marker. Enterocytozoon bieneusi was detected in 237 of all 660 (36%) faecal samples from goats (n = 89) and sheep (n = 148). Correlation analyses revealed that E. bieneusi positive rates were significantly associated with age-groups, seasons and locations (P < 0.05). The analysis of ITS sequence data revealed the presentation of eight known genotypes (BEB6, CD6, CHG1, CHG3, CHG5, CHS8, CM7 and SX1). Phylogenetic analysis of ITS sequence data sets showed that they clustered within Group 2, showing zoonotic potential. These findings suggested that goats and sheep in Ningxia harbor zoonotic genotypes of E. bieneusi and may have a significant risk for zoonotic transmission. Further insight into the epidemiology of E. bieneusi in farmed animals, water and the environment from other areas in China will be important to have an informed position on the public health significance of microsporidiosis caused by this microbe.

First identification and genotyping of Enterocytozoon bieneusi and Encephalitozoon spp. in pet rabbits in China

Background

Microsporidia are common opportunistic parasites in humans and animals, including rabbits. However, only limited epidemiology data concern about the prevalence and molecular characterization of Enterocytozoon bieneusi and Encephalitozoon spp. in rabbits. This study is the first detection and genotyping of Microsporidia in pet rabbits in China.

Results

A total of 584 faecal specimens were collected from rabbits in pet shops from four cities in Sichuan province, China. The overall prevalence of microsporidia infection was 24.8% by nested PCR targeting the internal transcribed spacer (ITS) region of E. bieneusi and Encephalitozoon spp. respectively. E. bieneusi was the most common species (n = 90, 15.4%), followed by Encephalitozoon cuniculi (n = 34, 5.8%) and Encephalitozoon intestinalis (n = 16, 2.7%). Mixed infections (E. bieneusi and E. cuniculi) were detected in five another rabbits (0.9%). Statistically significant differences in the prevalence of microsporidia were observed among different cities (χ² = 38.376, df = 3, P < 0.01) and the rabbits older than 1 year were more likely to harbour microsporidia infections (χ² = 9.018, df = 2, P < 0.05). Eleven distinct genotypes of E. bieneusi were obtained, including five known (SC02, I, N, J, CHY1) and six novel genotypes (SCR01, SCR02, SCR04 to SCR07). SC02 was the most prevalent genotype in all tested cities (43.3%, 39/90). Phylogenetic analysis showed that these genotypes were clustered into group 1–3 and group 10. Meanwhile, two genotypes (I and II) were identified by sequence analysis of the ITS region of E. cuniculi.

Conclusion

To the best of our knowledge, this is the first report of microsporidia infection in pet rabbits in China. Genotype SC02 and four novel genotypes were classified into potential zoonotic group 1, suggesting that pet rabbits may cause microsporidiosis in humans through zoonotic transmissions. These findings provide preliminary reference data for monitoring microsporidia infections in pet rabbits and humans.

Enterocytozoon bieneusi in donkeys from Xinjiang, China: prevalence, molecular characterization and the assessment of zoonotic risk

Background

Enterocytozoon bieneusi, a zoonotic pathogen, has the potential to infect both immunocompromised and immunocompetent humans. It is found in large number of animals; however, not much is known regarding its prevalence in equine animals, particularly donkeys. This is the first molecular epidemiological evaluation of E. bieneusi in 178 free-ranging donkeys from five countrysides; and 502 farmed donkeys from 18 farms in 12 cities of Xinjiang, China by Nested PCR.

Results

E. bieneusi was detected in 2.5% (17/680) donkeys, with 2.6% (13/502) in farmed and 2.2% (4/178) in free-ranging ones. Sequence analysis identified eight ITS genotypes, all belonging to zoonotic Groups 1 or 2, including six known genotypes: horse1 (n = 5), D (n = 3), NCD-2 (n = 3), BEB6 (n = 2), BEB4 (n = 1), and NIAI (n = 1); and two new genotypes: XJD1 (n = 1) and XJD2 (n = 1).

Conclusions

This is the first report confirming the presence of E. bieneusi in donkeys in Xinjiang, China, and indicates the possibility of zoonotic transmission of this pathogenic parasite.

Evidence for Zoonotic Potential of Enterocytozoon bieneusi in Its First Molecular Characterization in Captive Mammals at Bangladesh National Zoo

To determine the occurrence and genotypes of Enterocytozoon bieneusi in captive mammals at Bangladesh National Zoo and to assess their zoonotic significance, 200 fecal samples from 32 mammalian species were examined using a nested PCR and sequencing of internal transcribed spacer (ITS) gene. Enterocytozoon bieneusi was detected in 16.5% (33/200) of the samples. Seven different ITS genotypes were identified, including two known genotypes (D and J) and five new ones (BAN4 to BAN8). Genotype D was the most common genotype being observed in 19 isolates. In phylogenetic analysis, four genotypes (D, BAN4, BAN5, and BAN6), detected in 30 isolates (90.9%), belonged to Group 1 having zoonotic potential. The sequence of genotype J found in a Malayan pangolin was clustered in so-called ruminant-specific Group 2. The other two genotypes BAN7 and BAN8 were clustered in primate-specific Group 5. To our knowledge, this is the first report of molecular characterization of E. bieneusi in Bangladesh, particularly in captive-bred wildlife in this country. The potentially zoonotic genotypes of E. bieneusi are maintained in zoo mammals that may transmit among these animals and to the humans through environmental contamination or contact.

Molecular detection of Cryptosporidium and Enterocytozoon bieneusi in dairy calves and sika deer in four provinces in Northern China

The protistan pathogens Cryptosporidium and Enterocytozoon bieneusi can cause significant intestinal diseases in animals and humans. However, limited information is available regarding prevalence and molecular characterization of Cryptosporidium and E. bieneusi in ruminants in Northern China. In this study, the overall prevalence of Cryptosporidium and E. bieneusi was 19.3% (62/321) and 28.97% (93/321) in dairy calves and 1.10% (9/818) and 13.57% (111/818) in sika deer (Cervus nippon) in four provinces in Northern China, respectively. The prevalence of Cryptosporidium and E. bieneusi in different factor groups was various. Five Cryptosporidium species/genotypes were identified, of which C. parvum, C. ryanae, C. bovis, and C. andersoni were only found in dairy calves, and only Cryptosporidium deer genotype was found in sika deer. Moreover, J, I, and BEB4 ITS genotypes of E. bieneusi were found in dairy calves, and six known genotypes (JLD-III, JLD-IX, JLD-VII, EbpC, BEB6, and I) and ten novel genotypes (namely LND-I and JLD-XV to JLD-XXIII) were found in sika deer in this study. Cryptosporidium parvum and E. bieneusi genotype J were identified as the predominant species/genotypes in dairy calves, whereas the predominance of Cryptosporidium spp. and E. bieneusi in sika deer was Cryptosporidium deer genotype and BEB6, respectively. The present study reported the prevalence and genotypes of Cryptosporidium and E. bieneusi in dairy calves and sika deer in four provinces in northern China. The present findings also suggest that investigated dairy calves and sika deer may play an important role in the transmission of E. bieneusi and Cryptosporidium to humans and other animals, and also in an effort to better understand the epidemiology of these enteric pathogens in China.

Molecular characterization of Cryptosporidium and Enterocytozoon bieneusi in Père David's deer (Elaphurus davidianus) from Shishou, China

Cryptosporidium and Enterocytozoon bieneusi are important intestinal pathogens that infect humans and various animals. Few reports are available regarding the infections of the two pathogens in Père David's deer. In this study, polymerase chain reaction (PCR) confirmed Cryptosporidium infection in two (1.6%) and E. bieneusi in 45 (35.2%) of 128 fecal samples collected from Père David's deer in the National Nature Reserve of Shishou, Hubei Province, China. C. parvum (n = 1) and Cryptosporidium deer genotype (n = 1) were identified using the small subunit rRNA (SSU rRNA) gene. The C. parvum was further subtyped as IIdA20G1 by sequencing analysis of the 60-kDa glycoprotein (gp60) gene. The identity of E. bieneusi was confirmed by an internal transcribed spacer (ITS) gene; the HLJD-V (n = 42) and MWC_d1 (n = 3) genotypes were identified, with the former clustering in group 2 and the latter in group 1. These data suggest that the Père David's deer were infected with host-specific and/or zoonotic genotypes of these pathogens, implicating Père David's deer could be a potential source of human Cryptosporidium infection.

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C. parvum subtype IIdA20G1 was firstly identified in Pere David's deer.

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Genotypes HLJD-V and MWC_d1 were detected from 45 E. bieneusi-positive samples.

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The present study implicated Père David's deer could be a potential source of human infection.

Molecular Detection and Genotyping of Enterocytozoon bieneusi in Racehorses in China

Enterocytozoon bieneusi is a widely distributed human and animal pathogen. However, few data are available on the distribution of E. bieneusi genotypes in racehorses. In this study, 621 fecal specimens were collected from racehorses at 17 equestrian clubs in 15 Chinese cities. E. bieneusi was detected via nested polymerase chain reaction (PCR) amplification of the internal transcribed spacer (ITS) gene. The overall infection rate of E. bieneusi was 4.8% (30/621). Statistically significant differences were found in the prevalence of this parasite among the equestrian clubs (χ² = 78.464, df = 16, p < 0.01) and age groups (χ² = 23.686, df = 1, p < 0.01), but no sex bias was found among the racehorses for the E. bieneusi infections (χ² = 1.407, df = 2, p > 0.05). Ten E. bieneusi genotypes were identified, including seven known genotypes (EbpC, EbpA, Peru6, horse1, horse2, CAF1, and TypeIV) and three novel genotypes (HBH-1, SXH-1, and BJH-1). Phylogenetic analysis showed that EbpC, EbpA, Peru6, horse2, CAF1, TypeIV, BJH-1, and SXH-1 belonged to Group 1 of E. bieneusi, HBH-1 belonged to Group 2, and horse2 belonged to Group 6. Our findings advance the current knowledge of E. bieneusi prevalence and genotypes in racehorses in China.

New genotypes and molecular characterization of Enterocytozoon bieneusi in pet birds in Southwestern China

Enterocytozoon bieneusi, a unicellular enteric microsporidian parasite, can infect humans and a wide range of animals throughout the world. Although E. bieneusi has been identified in many animals, there is no information regarding the genotypes of E. bieneusi in pet birds in China. Birds are important sources of emerging infectious diseases that affect humans, and immunosuppressed individuals can be exposed to potential zoonotic agents shed by birds. The aim of the present study was to determine the prevalence and genotypic diversity of E. bieneusi in pet birds, as well as assessed its zoonotic potential. A total of 387 fecal samples were collected from Psittaciformes (n = 295), Passeriformes (n = 67), and Galliformes (n = 16) from four pet markets in Sichuan province, Southwestern China. The overall prevalence of E. bieneusi in pet birds was 25.1% based on nested polymerase chain reaction analysis of the internal transcribed spacer (ITS) region of the ribosomal RNA (rRNA) gene (Psittaciformes, 21.7%; Passeriformes, 37.3%; Galliformes, 50.0%). Eight genotypes of E. bieneusi were identified, including five known genotypes (D, SC02, BEB6, CHB1, and MJ5) and three novel genotypes (SCB-I, SCB-II, and SCB-III). In phylogenetic analysis, genotypes D and SC02 and one novel genotype SCB-II were clustered within group 1, genotype BEB6 was classified within group 2, and the remaining genotypes (CHB1, MJ5, SCB-I, and SCB-III) clustered with group 10. To the best of our knowledge, this is the first report of E. bieneusi infection in pet birds in China. Genotypes D, SC02, and BEB6 that have been previously identified in humans, were found in pet birds in this study, suggesting that these pet birds can be a potential source of human microsporidiosis in China.

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This is the first to report the prevalence of E. bieneusi in pet birds in China.

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The overall prevalence of E. bieneusi was 25.1% (97/387) based on PCR analysis of the ITS region of the ribosomal RNA gene.

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Five known genotypes (D, SC02, BEB6, CHB1, and MJ5) and three novel genotypes (SCB-I, SCB-II, and SCB-III) were identified.

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This study will enrich the epidemiological data of E. bieneusi infection in China.

Enterocytozoon bieneusi genotypes in cats and dogs in Victoria, Australia

BACKGROUND

Enterocytozoon bieneusi is one of the commonest microsporidians contributing to human microsporidiosis, and is frequently found in animals in various countries. However, there is limited epidemiological information on this microorganism in Australia. Here, we undertook the first molecular epidemiological study of E. bieneusi in cats and dogs in Victoria.

RESULTS

Genomic DNAs were extracted from 514 individual faecal deposits from cats (n = 172) and dogs (n = 342) and then tested using PCR-based sequencing of the internal transcribed spacer (ITS) of nuclear ribosomal DNA. Four distinct genotypes (designated D, PtEb IX, VIC_cat1 and VIC_dog1) of E. bieneusi were identified in 20 of the 514 faecal samples (3.9%). Genotype D is known to have a broad host range (humans and other animals) and has a wide geographical distribution around the world. The identification of this genotype here suggests that companion animals might represent reservoir hosts that are able to transmit E. bieneusi infection to humans in Australia. A phylogenetic analysis of ITS sequence data revealed that the novel genotype VIC_cat1 is related to the known genotype type IV within Group 1, and the new genotype VIC_dog1 is linked to a contentious "Group 3", which includes genotypes reported previously in the published literature to represent Group 2 or 3.

CONCLUSIONS

A future, large-scale phylogenetic study of all known E. bieneusi genotypes, including VIC_dog1, should aid in clarifying their relationships and assignment to Groups, and in the identification of new genotypes, thus assisting epidemiological investigations.

Are molecular tools clarifying or confusing our understanding of the public health threat from zoonotic enteric protozoa in wildlife?

Emerging infectious diseases are frequently zoonotic, often originating in wildlife, but enteric protozoa are considered relatively minor contributors. Opinions regarding whether pathogenic enteric protozoa may be transmitted between wildlife and humans have been shaped by our investigation tools, and have led to oscillations regarding whether particular species are zoonotic or have host-adapted life cycles. When the only approach for identifying enteric protozoa was morphology, it was assumed that many enteric protozoa colonized multiple hosts and were probably zoonotic. When molecular tools revealed genetic differences in morphologically identical species colonizing humans and other animals, host specificity seemed more likely. Parasites from animals found to be genetically identical - at the few genes investigated - to morphologically indistinguishable parasites from human hosts, were described as having zoonotic potential. More discriminatory molecular tools have now sub-divided some protozoa again. Meanwhile, some infection events indicate that, circumstances permitting, some "host-specific" protozoa, can actually infect various hosts. These repeated changes in our understanding are linked intrinsically to the investigative tools available. Here we review how molecular tools have assisted, or sometimes confused, our understanding of the public health threat from nine enteric protozoa and example wildlife hosts (Balantoides coli - wild boar; Blastocystis sp. - wild rodents; Cryptosporidium spp. - wild fish; Encephalitozoon spp. - wild birds; Entamoeba spp. - non-human primates; Enterocytozoon bieneusi - wild cervids; Giardia duodenalis - red foxes; Sarcocystis nesbitti - snakes; Toxoplasma gondii - bobcats). Molecular tools have provided evidence that some enteric protozoa in wildlife may infect humans, but due to limited discriminatory power, often only the zoonotic potential of the parasite is indicated. Molecular analyses, which should be as discriminatory as possible, are one, but not the only, component of the toolbox for investigating potential public health impacts from pathogenic enteric protozoa in wildlife.

First report and multilocus genotyping of Enterocytozoon bieneusi from Tibetan pigs in southwestern China

Enterocytozoon bieneusi is a common intestinal pathogen in a variety of animals. While E. bieneusi genotypes have become better-known, there are few reports on its prevalence in the Tibetan pig. This study investigated the prevalence, genetic diversity, and zoonotic potential of E. bieneusi in the Tibetan pig in southwestern China. Tibetan pig feces (266 samples) were collected from three sites in the southwest of China. Feces were subjected to PCR amplification of the internal transcribed spacer (ITS) region. Enterocytozoon bieneusi was detected in 83 (31.2%) of Tibetan pigs from the three different sites, with 25.4% in Kangding, 56% in Yaan, and 26.7% in Qionglai. Prevalence varies according to age group, from 24.4% (age 0-1 years) to 44.4% (age 1-2 years). Four genotypes of E. bieneusi were identified: two known genotypes EbpC (n = 58), Henan-IV (n = 24) and two novel genotypes, SCT01 and SCT02 (one of each). We compare our results with a compilation of published results on the host range and geographical distribution of E. bieneusi genotypes in China. Phylogenetic analysis showed these four genotypes clustered to group 1 with zoonotic potential. Multilocus sequence typing (MLST) analysis of three microsatellites (MS1, MS3, MS7) and one minisatellite (MS4) was successful in 47, 48, 23 and 47 positive specimens and identified 10, 10, 5 and 5 genotypes at four loci, respectively. This study indicates the potential danger of E. bieneusi to Tibetan pigs in southwestern China, and offers basic advice for preventing and controlling infections.

Prevalence and genotypes of Enterocytozoon bieneusi in wildlife in Korea: a public health concern

Background

Enterocytozoon bieneusi is a unicellular microsporidian fungal pathogen that infects a broad range of animal hosts, including wild and domestic animals and humans. The infection burden of this parasite in wild animals in Korea is largely unknown. In this study, the occurrence and genotypes of E. bieneusi were investigated in wild animal populations in Korea.

Methods

A total of 157 fecal samples (97 from Korean water deer, 48 from raccoon dogs and 12 from other taxa) were collected from wild animals at five wildlife centers in Korea. Genomic DNA was extracted from the samples and screened by nested-PCR targeting the internal transcribed spacer (ITS) region of rRNA, followed by sequence analysis to determine the genotype(s) of E. bieneusi.

Results

The overall prevalence of E. bieneusi was 45.2% (71/157), with rates of 53.6% (52/97) in Korean water deer, 35.4% (17/48) in raccoon dogs and 16.7% (2/12) in other taxa. We detected seven ITS genotypes, including one known (genotype D) and six new genotypes (Korea-WL1–Korea-WL6). Phylogenetically, all detected genotypes clustered with counterparts belonging to group 1, which includes isolates from different animal hosts and humans, suggesting their zoonotic potential.

Conclusions

Our survey results indicate that E. bieneusi circulates widely in wild animals in Korea. These findings address the role of wildlife as a potential source of microsporidiosis in domestic animals and humans.

First report of Enterocytozoon bieneusi and Cryptosporidium spp. in peafowl (Pavo cristatus) in China

Enterocytozoon bieneusi and Cryptosporidium spp. are important pathogens causing diarrhea in humans and animals. However, few studies have been conducted on the infection of E. bieneusi and Cryptosporidium spp. in peafowl up to now. The purpose of the present study was to determine the prevalence and the involved genotypes of Cryptosporidium spp. and E. bieneusi in peafowl in Beijing and Jiangxi Province, China. In total, 258 peafowl fecal samples were collected. Overall, both Cryptosporidium spp. and E. bieneusi had the same prevalence, i.e. 6.59% (17/258). Higher infection rates of E. bieneusi and Cryptosporidium spp. were found in the adolescent peafowl. The prevalence of E. bieneusi in Beijing and Jiangxi Province was 5.23% and 8.57% respectively. For Cryptosporidium spp., the prevalence was 4.58% and 9.52% in Beijing and Jiangxi Province, respectively. Three zoonotic genotypes of E. bieneusi were confirmed, including two known genotypes, genotype Peru 6 and D, and one novel genotype, JXP1. Two avian specific species/genotypes of Cryptosporidium, Avian genotype Ⅲ and Goose genotype Ⅰ, were identified. To our knowledge, this is the first report of E. bieneusi and Cryptosporidium spp. occurrence in peafowl in China. The findings suggest that peafowl could be reservoirs of E. bieneusi and Cryptosporidium spp. which could be potentially transmitted to humans and other animals, and the present survey have implications for controlling E. bieneusi and Cryptosporidium spp. infection in peafowl.

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This is the first report of Enterocytozoon bieneusi and Cryptosporidium spp. in peafowl in China.

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The average infection rate was 6.59% and higher prevalence was found in the adolescent peafowl.

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Three zoonotic genotypes of E. bieneusi and 2 avian specific genotypes of Cryptosporidium were identified.

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This study will enrich the epidemiological data of E. bieneusi and Cryptosporidium spp. infection in China.

First cross-sectional, molecular epidemiological survey of Cryptosporidium, Giardia and Enterocytozoon in alpaca (Vicugna pacos) in Australia

BACKGROUND

Eukaryotic pathogens, including Cryptosporidium, Giardia and Enterocytozoon, have been implicated in neonatal diarrhoea, leading to marked morbidity and mortality in the alpaca (Vicugna pacos) and llama (Lama glama) around the world. Australia has the largest population of alpacas outside of South America, but very little is known about these pathogens in alpaca populations in this country. Here, we undertook the first molecular epidemiological survey of Cryptosporidium, Giardia and Enterocytozoon in V. pacos in Australia.

METHODS

A cross-sectional survey of 81 herds, comprising alpacas of 6 weeks to 26 years of age, were sampled from the six Australian states (Queensland, New South Wales, Victoria, South Australia, Tasmania and Western Australia) across the four seasons. PCR-based sequencing was employed, utilising genetic markers in the small subunit of the nuclear ribosomal RNA (SSU) and 60-kilodalton glycoprotein (gp60) genes for Cryptosporidium, triose-phosphate isomerase (tpi) gene for Giardia duodenalis and the internal transcribed spacer region (ITS) for Enterocytozoon bieneusi.

RESULTS

PCR-based analyses of 81 faecal DNA samples representing 1421 alpaca individuals detected Cryptosporidium, Giardia and/or Enterocytozoon on 15 farms in New South Wales, Victoria and South Australia, equating to 18.5% of all samples/herds tested. Cryptosporidium was detected on three (3.7%) farms, G. duodenalis on six (7.4%) and E. bieneusi on eight (9.9%) in two or all of these three states, but not in Queensland, Tasmania or Western Australia. Molecular analyses of selected faecal DNA samples from individual alpacas for Cryptosporidium, Giardia and/or Enterocytozoon consistently showed that alpacas of ≤ 6 months of age harboured these pathogens.

CONCLUSIONS

This first molecular investigation of Cryptosporidium, Giardia and Enterocytozoon in alpaca subpopulations in Australia has identified species and genotypes that are of likely importance as primary pathogens of alpacas, particularly young crias, and some genotypes with zoonotic potential. Although the prevalence established here in the alpaca subpopulations studied is low, the present findings suggest that crias are likely reservoirs of infections to susceptible alpacas and/or humans. Future studies should focus on investigating pre-weaned and post-weaned crias, and on exploring transmission patterns to establish what role particular genotypes play in neonatal or perinatal diarrhoea in alpacas and in zoonotic diseases in different states of Australia.

Molecular surveillance of Vittaforma-like microsporidia by a small-volume procedure in drinking water source in Taiwan: evidence for diverse and emergent pathogens

Vittaforma corneae belongs to microsporidia, which include over 1500 species of opportunistic obligate intracellular fungi infecting almost all known animal taxa. Although outbreaks of ocular infections caused by waterborne V. corneae have been reported in recent years, little is known about the occurrence of this pathogen in aquatic environments. In this study, 50 water samples from rivers and reservoirs around Taiwan in two seasons were analyzed to explore the presence of this pathogen in natural aquatic environments. A high detection rate of Vittaforma-like amplicons (94%; 47/50) was observed in the water samples when examined by nested PCR with primer pairs specific to the small ribosomal subunit (SSU) rRNA gene. After electrophoresis, many lanes showed multiband patterns with expected molecular weights. After confirmation by DNA sequencing and by sequence alignment in the NCBI database, we identified a variety of Vittaforma-like microsporidia with weak sequence similarity, with approximately 85% identity to V. corneae, thus indicating high diversity of microsporidia in aquatic environments. Phylogenetic analysis showed clear-cut microsporidian clade classification and indicated that the most Vittaforma-like microsporidia in this study belong to clade IV and cluster into four major groups. The first group is similar to the microsporidia associated with ocular microsporidiosis. The second group is associated with the diarrheal pathogens, whereas the third and fourth groups are a novel group and a zoonotic group, respectively. This study provides abundant sequencing information, which will be useful for future molecular biological studies on microsporidia. Because microsporidia are important pathogens of animals and humans, it is urgently necessary to determine via a survey whether there are species with potential threats that have not yet been revealed.

New operational taxonomic units of Enterocytozoon in three marsupial species

Background

Enterocytozoon bieneusi is a microsporidian, commonly found in animals, including humans, in various countries. However, there is scant information about this microorganism in Australasia. In the present study, we conducted the first molecular epidemiological investigation of E. bieneusi in three species of marsupials (Macropus giganteus, Vombatus ursinus and Wallabia bicolor) living in the catchment regions which supply the city of Melbourne with drinking water.

Methods

Genomic DNAs were extracted from 1365 individual faecal deposits from these marsupials, including common wombat (n = 315), eastern grey kangaroo (n = 647) and swamp wallaby (n = 403) from 11 catchment areas, and then individually tested using a nested PCR-based sequencing approach employing the internal transcribed spacer (ITS) and small subunit (SSU) of nuclear ribosomal DNA as genetic markers.

Results

Enterocytozoon bieneusi was detected in 19 of the 1365 faecal samples (1.39%) from wombat (n = 1), kangaroos (n = 13) and wallabies (n = 5). The analysis of ITS sequence data revealed a known (designated NCF2) and four new (MWC_m1 to MWC_m4) genotypes of E. bieneusi. Phylogenetic analysis of ITS sequence data sets showed that MWC_m1 (from wombat) clustered with NCF2, whereas genotypes MWC_m2 (kangaroo and wallaby), MWC_m3 (wallaby) and MWC_m4 (kangaroo) formed a new, divergent clade. Phylogenetic analysis of SSU sequence data revealed that genotypes MWC_m3 and MWC_m4 formed a clade that was distinct from E. bieneusi. The genetic distinctiveness of these two genotypes suggests that they represent a new species of Enterocytozoon.

Conclusions

Further investigations of Enterocytozoon spp. from macropods and other animals will assist in clarifying the taxonomy and epidemiology of these species in Australia and elsewhere, and in assessing the public health risk of enterocytozoonosis.

Electronic supplementary material

The online version of this article (10.1186/s13071-018-2954-x) contains supplementary material, which is available to authorized users.