First report on the molecular prevalence of Enterocytozoon bieneusi in horses in Turkey: genotype distributions and zoonotic potential

Occurrence and molecular characterization of Enterocytozoon bieneusi in water buffaloes (Bubalus bubalis) in Turkey

Microsporidia are obligate intracellular fungus-like parasites that infect humans and animals worldwide. However, there is limited epidemiological data on the occurrence and molecular diversity of microsporidia in buffaloes worldwide. In the present study, fecal samples of 300 water buffaloes (Bubalus bubalis) in Kayseri, Sivas, and Samsun provinces of Turkey were investigated using two nested PCR assays targeting the rRNA of E. bieneusi and Encephalitozoon spp. All the fecal samples from water buffalo were found to be negative for Encephalitozoon spp. PCR positive isolates of E. bieneusi were bidirectionally sequenced for genotyping and phylogenetic analyses. Enterocytozoon bieneusi was the only microsporidian species identified in 8 water buffaloes with an overall molecular prevalence of 2.7%. Two known genotypes, YNDCEB-90 (n = 5) and J (n = 3) were identified by ITS sequence analysis. The YNDCEB-90 and J genotypes fall into zoonotic Group 1 and 2 of E. bieneusi in the phylogenetic tree, respectively. These findings suggested that water buffalo in Turkey are harbouring zoonotic genotypes of E. bieneusi and may have a significant risk for zoonotic transmission to humans. This is the first report of detecting E. bieneusi genotypes J and YNDCEB-90 in water buffaloes. Further insight into the epidemiology of E. bieneusi in water buffaloes in different geographical areas in Turkey will be highly important to have determined the public health significance of this pathogen.

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.

Enterocytozoon bieneusi Genotypes and Infections in the Horses in Korea

Enterocytozoon bieneusi is a microsporidian pathogen. Recently, the equestrian population is increasing in Korea. The horse-related zoonotic pathogens, including E. bieneusi, are concerns of public health. A total of 1,200 horse fecal samples were collected from riding centers and breeding farms in Jeju Island and inland areas. Of the fecal samples 15 (1.3%) were PCR positive for E. bieneusi. Interestingly, all positive samples came from Jeju Island. Diarrhea and infection in foals were related. Two genotypes (horse1, horse2) were identified as possible zoonotic groups requiring continuous monitoring.

Molecular epidemiology and genotype/subtype distribution of Blastocystis sp., Enterocytozoon bieneusi, and Encephalitozoon spp. in livestock: concern for emerging zoonotic infections

Intestinal parasitic infections have high prevalence rate in many regions especially in developing countries. The aim of this study was to determine the presence and genotype/subtype of some intestinal protozoa in livestock in Iran. Stool samples were collected from cattle, sheep, chickens, and horses. The presence of targeted parasites was evaluated using real-time PCR. Genotyping/subtyping of positive samples was characterized using sequencing of the ITS and barcoding region, respectively. Blastocystis sp., 27.7% (48/173) and Enterocytozoon bieneusi 26.0% (45/173) were the most frequent protozoa followed by Encephalitozoon spp., 0.57% (1/173). Cryptosporidium spp. were not detected among samples. Encephalitozoon spp., was detected only in chickens 2.2% (1/45). A statistically correlation was seen between animals and the prevalence of targeted protozoa. E. bieneusi genotypes I (9/38; 23.68%), BEB6 (22/38; 57.89%), D (6/38; 15.79%), and horse1 (1/38; 2.63%) were detected among samples. A statistically significant correlation was seen between the genotypes and animals (P ≤ 0.05). Blastocystis sp., ST1 (1/45; 2.22%), ST5 3/45; 6.66%), ST7 (1/45; 2.22%), ST10 (24/45; 53.33%), and ST14 (16/45; 35.55%) were characterized among samples. There was no significant correlation between certain subtypes and animals (P = 0.173). The presence of zoonotic potential genotypes of E. bieneusi in animals and zoonotic potential subtypes ST1 and ST7 among our samples provide a clue about the transmission dynamic of E. bieneusi and Blastocystis sp. between animals–animals and humans–animals.

First genotyping of Enterocytozoon bieneusi in plateau pikas (Ochotona curzoniae) from the Qinghai Plateau, Northwest China

Enterocytozoon bieneusi is considered the most common microsporidian species and is frequently detected in humans and various animals worldwide. However, information on E. bieneusi infection in plateau pikas (Ochotona curzoniae) is somewhat limited. Therefore, this study was conducted to determine the infection status and genotype characteristics of E. bieneusi in plateau pikas in China. A total of 33 fresh fecal samples were collected from plateau pikas captured on the Qinghai Plateau. By PCR assay and DNA sequencing of the ITS gene, 5 (15.2%, 5/33) isolates were diagnosed as positive. Sequence analysis revealed the presence of one known sheep-derived genotype, CHS17 (4/5), and a novel E. bieneusi genotype, CHPP1 (1/5), with maximum shared identity with the CHS17 genotype. Phylogenetically, these isolates were clustered into subgroup 1i of zoonotic group 1 with genotypes CHS17 and CHN14 from plateau ruminants, but the new CHP1 genotype formed a cluster separate from those genotypes. This is the first report of E. bieneusi in plateau pikas. The findings suggested that these animals might be potential reservoirs of zoonotic E. bieneusi, and transmission of the pathogen between plateau pikas and sheep probably occurs in the region.

Global prevalence of microsporidia infection in cats: A systematic review and meta-analysis of an emerging zoonotic pathogen

Microsporidiosis in pet and stray cats is an emerging zoonotic threat with public health significance worldwide. However, the epidemiological patterns of feline microsporidiosis is still neglected around the world. Hence, current systematic review and meta-analysis aimed at characterizing the prevalence estimates and genotypes of microsporidian parasites among cats of the world. Several databases (PubMed, Web of Science, Scopus, and Google scholar) were systematically explored to find relevant studies. Evaluation of the weighted prevalences among included studies was done using random-effects model. Totally, 30 studies (34 datasets) reported from 19 countries were included in the present work. Microsporidia infection demonstrated higher prevalence rates using microscopy 29.7 % (19.7-42.2 %), followed by serology and molecular techniques with 11 % (4.6-24.2 %) and 8.2 % (5.9-11.4 %), respectively. Moreover, molecular data showed Enterocytozoon bieneusi as the most dominant reported species with 7.4 % (5.1-10.5 %). Also, investigations (11 studies) mostly isolated D genotype among all E. bieneusi genotypes. These results highlight cats as a potential reservoir for acquisition of microsporidia infection in humans, and surveillance programs should be implemented in high-risk areas.