Enterocytozoon bieneusi (E. bieneusi), which is one of the most common microsporidia, has been identified as an important obligate intracellular pathogen that commonly colonizes in a variety of animal species and humans worldwide, including humans. In this study, the statistical analyses of E. bieneusi infection and prevalence were performed to clarify the relationship between different genotypes in different countries. The databases Chinese National Knowledge Infrastructure (CNKI), VIP Chinese Journal Database, Wanfang Data, PubMed, Web of Science and ScienceDirect were used for data collection. The research data were subjected to subgroup, univariate regression, and correlation, to reveal factors related to the high prevalence of E. bieneusi. A total of, 34 of the 498 articles published before April 2022 met the inclusion criteria. The global prevalence of E. bieneusi in pigs was 37.69% (5175/12672). The prevalence of E. bieneusi in nursery pigs was 58.87% (588/946). In developing countries and Asia, the highest prevalence of E. bieneusi in pigs were 37.62% (4752/11645) and 40.14% (4715/11345), respectively. Moreover, humans and pigs have been found to be infected with the same genotype of E. bieneusi in some cases, as evidenced by the consolidation of genotype information. The results showed that pigs are susceptible to E. bieneusi during the nursery period. The prevalence of E. bieneusi is high in developing countries, and its genotype prevalence varies in each country. Thus, it is essential to strengthen the health inspection of vulnerable groups and customs quarantine inspection.

Blastocystis sp., Enterocytozoon bieneusi, and Giardia duodenalis are three common zoonotic intestinal parasites, and cattle are important hosts of these three intestinal protozoa. In this study, 1632 fecal samples were collected from dairy farms in Heilongjiang Province, China, and screened for Blastocystis sp., E. bieneusi, and G. duodenalis using polymerase chain reaction. Of these, 149 (9.13%) were positive for three zoonotic pathogens, including 104 (6.40%), 22 (1.35%), and 23 (1.41%) for Blastocystis sp., E. bieneusi, and G. duodenalis, respectively. Based on partial SSU rRNA gene sequencing analysis, 104 positive samples of Blastocystis sp. were found, and a total of nine known subtypes were identified, including ST10 (61), ST3 (18), ST14 (6), ST26 (7), ST24 (3), ST25 (2), ST1 (2), ST5 (2), and ST21 (1). Among these, three subtypes (ST1, ST3, and ST5) were recognized as zoonotic subtypes, and two subtypes (ST10 and ST14) were specific to animals. All 23 Giardia duodenalis-positive samples belonged to assemblage E (n = 23) based on sequenced beta-giardin (bg) and triosephosphate isomerase (tpi) genes. Three known genotypes of E. bieneusi, namely J (n = 9), I (n = 6), and BEB4 (n = 7), were identified by sequence analysis of the internal transcriptional spacer region gene. Our study provides basic data for prevention and control in Heilongjiang Province; however, further research is required to better understand the prevalence and public health significance of these pathogens in the Heilongjiang region.

BACKGROUND: The aim of this study was to identify Enterocytozoon bieneusi and Encephalitozoon spp. in fecal samples of HIV + /AIDS and cancer patients undergoing chemotherapy, and comparing the results to healthy individuals in Mazandaran province, north of Iran.
METHODS: Stool samples were collected from 50 HIV + /AIDS patients, 50 cancer patients, and 50 healthy samples referred to medical centers in north of Iran. Stool samples were kept in 2.5% potassium dichromate at 4 °C, and stained by modified trichrome for light microscopy examination. The multiplex/nested-PCR targeted the small subunit ribosomal RNA (SSU rRNA) gene. To characterize genotypes, the nested PCR products sequenced by Bioneer Company and was subjected to phylogenetic analyses.
RESULTS: Ten of 50 samples (20%) of HIV + /AIDS patients, 5 of 50 samples (10%) of cancer patients, and 1 of healthy individuals (2%) were microscopically positive. From 50 HIV + / AIDS patients, E. bieneusi and Encephalitozoon spp. were detected in 10 (20%) and 6 (12%) cases, respectively. Furthermore, among cancer patients, 7 (14%) and 2 (4%) cases were E. bieneusi and Encephalitozoon spp., respectively. Out of 50 samples of healthy individuals, only 3 (6%) cases of E. bieneusi were observed. The genotypes D and M were detected among positive samples of E. bieneusi.
CONCLUSIONS: E. bieneusi and then Encephalitozoon spp. are common intestinal microsporidia in HIV + /AIDS patients and cancer patients undergoing chemotherapy in Mazandaran province. E. bieneusi genotype D seems to be the predominant genotype in Mazandaran province. Due to the considerable prevalence of intestinal microsporidia, physicians are advised to pay more attention to this opportunistic infection in high-risk groups.

Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi are significant parasitic gastrointestinal pathogens with global distribution in humans and domestic animals, including calves. The main symptoms of calf infection are severe diarrhea, dehydration, growth retardation, and sometimes even death. To date, there has been limited information on the prevalence of Cryptosporidium spp., G. duodenalis, and E. bieneusi infections in calves in Ningxia, China, especially between diarrheic and non-diarrheic calves. A total of 438 fecal samples were collected from diarrheic (201) and non-diarrheic (237) calves in Ningxia. PCR and DNA sequencing were used to find the prevalence of Cryptosporidium spp. at 46.8% (205/438), G. duodenalis at 16.9% (74/438), and E. bieneusi at 10.0% (44/438). The prevalence of Cryptosporidium spp. infection in diarrheic and non-diarrheic calves was 54.0% (128/237) and 38.3% (77/201), respectively, and statistical analysis showed a positive correlation between the prevalence of Cryptosporidium spp. infection and calf diarrhea (p < 0.01). However, in this study, there was no statistical correlation between the prevalence of G. duodenalis infection as well as E. bieneusi infection and calf diarrhea (p > 0.05). Furthermore, four known Cryptosporidium species were successfully identified by comparing them with SSU rRNA gene sequences, including C. parvum, C. bovis, C. ryanae, and C. andersoni. In addition, all 74 G. duodenalis-positive samples were identified as assemblage E by comparative analysis of bg gene sequences. Among the 44 E. bieneusi-positive samples sequenced in the present study, 4 distinct E. bieneusi genotypes were successfully identified by comparative analysis of ITS sequences, including 3 known genotypes (J, BEB4, and N) and 1 novel genotype, the latter of which was identified and designated as NX1. These findings indicated that the high genetic diversity and complex population structures of Cryptosporidium spp., G. duodenalis, and E. bieneusi in Ningxia diarrhea calves and non-diarrhea calves, which provide new data for understanding the epidemiological status of Cryptosporidium spp., G. duodenalis, and E. bieneusi in Ningxia calves.

Enterocytozoon bieneusi is the most common microsporidian pathogen in farm animals and humans. Although several spore wall proteins (SWPs) of other human-pathogenic microsporidia have been identified, SWPs of E. bieneusi remain poorly characterized. In the present study, we identified the sequences of three E. bieneusi SWPs from whole genome sequence data, expressed them in Escherichia coli, generated a monoclonal antibody (mAb) against one of them (EbSWP1), and used the mAb in direct immunofluorescence detection of E. bieneusi spores in fecal samples. The amino acid sequence of EbSWP1 shares some identity to EbSWP2 with a BAR2 domain, while the sequence of EbSWP3 contains a MICSWaP domain. No cross-reactivity among the EbSWPs was demonstrated using the polyclonal antibodies generated against them. The mAb against EbSWP1 was shown to react with E. bieneusi spores in fecal samples. Using chromotrope 2R staining-based microscopy as the gold standard, the sensitivity and specificity of the direct immunofluorescence for the detection of E. bieneusi were 91.4 and 73.7%. Data generated from the study could be useful in the characterization of E. bieneusi and immunological detection of the pathogen.

BACKGROUND: Captive wild animals in zoos infected with Cryptosporidium spp., Giardia duodenalis, Enterocytozoon bieneusi, and Blastocystis sp. can be sources of zoonotic infections and diseases. Therefore, to investigate the distribution of these pathogens in captive wild animals of zoos in Henan, China, a total of 429 fresh fecal samples were collected from six zoos in Henan, China. The infection rates of Cryptosporidium spp., G. duodenalis, E. bieneusi, and Blastocystis sp. were determined by PCR analysis of corresponding loci. Positive results for Cryptosporidium (C. parvum and C. hominis) were subtyped based on the (gp60) gene.
RESULTS: The overall prevalence was 43.1% (185/429), and the prevalence of Cryptosporidium, Giardia duodenalis, Enterocytozoon bieneusi, and Blastocystis sp. were 2.8% (12/429), 0.5% (2/429), 20.8% (89/429), and 19.1% (82/429), respectively. Five Cryptosporidium species, namely, C. hominis, C. parvum, C. muris, C. andersoni, and C. macropodum, were identified in this study. Cryptosporidium parvum was further subtyped as IIdA19G1. Two Giardia duodenalis assemblages (A and E) were also identified. A total of 20 Enterocytozoon bieneusi genotypes were detected, including 18 known (BEB6, D, HND-1, CD7, SDD1, Henan-IV, KIN-1, CHK1, Peru8, Henan-V, CHG11, CHG-1, CHS9, CHG21, Type-IV, CHC9, CM5, and CHB1) and 2 novel genotypes (CHWD1 and CHPM1). A total of nine subtypes of Blastocystis sp. (ST1, ST2, ST3, ST5, ST6, ST7, ST10, ST13, and ST14) were identified in captive wild animals in zoos in the present study. Cryptosporidium andersoni, nine Enterocytozoon bieneusi genotypes, and five Blastocystis subtypes were here first identified in new hosts.
CONCLUSIONS: Our study has expanded the host ranges of these four pathogens. The data indicate that animals in zoos can commonly be infected with these four zoonotic pathogens, and animals in zoos are potential sources of zoonotic infections in humans.

BACKGROUND: Enterocytozoon bieneusi, a common opportunistic fungal pathogen, has a wide range of hosts. Limited epidemiological data on E. bieneusi intestinal infections in companion animals (dogs and cats) in China exists. In this study, fecal samples (651 from dogs and 389 from cats) in Guangzhou city, Guangdong Province, China, were collected, and the ribosomal internal transcribed (ITS) spacer region from the DNA extracted from them was Polymerase Chain Reaction (PCR)-amplified and sequenced.
RESULTS: Based on the sequencing data, E. bieneusi was identified in the fecal samples collected from 149 (22.9%) and 79 (20.3%) dogs and cats. Of the factors investigated, poor living conditions appeared to be the major risk factor for contracting the pathogen. Eleven E. bieneusi genotypes, six known (PtEb IX, GD1, D, CD9, EbpC, I) and five novel (designated here as GD2- GD6), were found in dogs. Eight genotypes, six known (PtEb IX, GD1, D, CD9, EbpC, Type IV) and two novel (GD2 and GC1), were identified in cats. Genotype PtEb IX was most common in both dogs and cats, followed by genotype GD1.
CONCLUSIONS: Although PtEb IX was the most common E. bieneusi genotype in dogs, this is the first report of this genotype dominating in cats. The same genotype distribution of the pathogen between the two different companion animals species in the same geographic area indicates that inter-species transmission is probable. The widespread existence of zoonotic E. bieneusi genotypes (D, EbpC, Type IV) in companion animals indicates that they are potential sources of environmental contamination and infections in humans.

Enterocytozoon bieneusi is an emerging zoonotic intestinal pathogen that infects humans and various animal species. Here, we aimed to determine the infection rate and genetic characteristics of E. bieneusi from bamboo rats from different regions of China using nested polymerase chain reaction-based amplification of the internal transcribed spacer region of the rRNA gene. A total of 435 bamboo rats fecal samples were collected from individual tank from Guangdong, Hunan, Jiangxi, Chongqing, and Guangxi, southeastern China. E. bieneusi was detected on 22 tanks (5.1%, 22/435), with a higher infection rate being observed among samples from Guangdong Province (10.9%, 5/46) compared with those from Hunan (9.3%, 10/107), Jiangxi (6.7%, 6/90), Chongqing (2.0%, 1/50), and Guangxi (0%, 0/142) (P < .01). Six genotypes were identified, including four known genotypes (D, EbpA, J, and PigEBITS7) and two novel genotypes (named BR1 and BR2). Of these, zoonotic genotype D was the most prevalent in the present study (n = 17). Phylogenetic analysis revealed that genotypes D, EbpA, and PigEBITS7 were clustered into Group 1, while genotypes J, BR1, and BR2 were clustered into Group 2. To our knowledge, this is the first report of E. bieneusi in bamboo rats. The identification of zoonotic genotype D as the predominant genotype in bamboo rats suggests that these animals represent a potential zoonotic risk for the transfer of the pathogen in China.

To assess the prevalence and molecular characteristics of Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi in grazing adult sheep from Xinjiang Uygur Autonomous Region, China, 318 fecal samples were collected and screened for the presence of these parasites by polymerase chain reaction. The overall infection rate for the three pathogens was 13.5% (43/318), with observed individual infection rates of 0.9% (3/318), 7.5% (24/318), and 6.3% (20/318) for Cryptosporidium spp., G. duodenalis, and E. bieneusi, respectively. Three Cryptosporidium species were identified amongst the samples, including C. xiaoi (n = 1), C. ubiquitum (n = 1), and C. parvum (n = 1), with gp60-based subtyping analysis identifying C. parvum as subtype IIdA15G1 and C. ubiquitum as subtype XIIa. Eight E. bieneusi genotypes were identified based on internal transcribed spacer region sequencing, including six known (BEB6, CHG1, CHG3, CHS3, CHS8, and COS-I) and two novel (designated XJS1 and XJS2) genotypes. All G. duodenalis-positive samples were identified as assemblage E based on small subunit rRNA (n = 24) and gdh (n = 10) gene sequence analysis. These data support the occurrence of host adaptation by Cryptosporidium spp., G. duodenalis, and E. bieneusi in sheep, and the zoonotic risk may posed by these parasites in Xinjiang, China.

Cryptosporidium spp., Giardia duodenalis, and Enterocytozoon bieneusi are globally ubiquitous pathogens. However, little is known about the occurrence and distribution of Cryptosporidium spp., G. duodenalis, and E. bieneusi in Tibetan sheep. In the present study, fecal specimens of 177 Tibetan sheep were examined by nested PCR. 4.5% (n = 8), 1.7% (n = 3) and 34.5% (n = 61) of the Tibetan sheep were positive for Cryptosporidium spp., G. duodenalis, and E. bieneusi, respectively. Cryptosporidium ubiquitum was the only species found by small subunit (SSU) rRNA-based PCR, and subtyping of C. ubiquitum (n = 6) by 60-kDa glycoprotein (gp60) revealed that all positive isolates belonged to zoonotic XIIa subtype 2. Multilocus genotyping at the SSU rRNA and β-giardin (bg) genes suggested that three G. duodenalis positive specimens belonged to assemblage E. Sequences analysis of internal transcribed spacer (ITS) gene characterized four E. bieneusi genotypes which all belonged to Group 2, one novel CGS1 (n = 3), and three known: CM7 (n = 34), BEB6 (n = 22), and CHS3 (n = 2). We employed multilocus sequence typing (MLST) using three microsatellites (MS1, MS3 and MS7), one minisatellite (MS4), and sequence analysis of MLST yielded 3, 2, 2 and 2 genotypes at the MS1, MS3, MS4, and MS7 loci, respectively, forming 4 MLGs. Our findings elucidate the occurrence and distribution of three zoonotic pathogens in Tibetan sheep in China. More subsequent and detailed data are required to better understand the transmission of Cryptosporidium spp., G. duodenalis, and E. bieneusi in sheep.