Elsevier

Research in Veterinary Science

Volume 133, December 2020, Pages 251-261
Research in Veterinary Science

Diagnosis and molecular typing of Enterocytozoon bieneusi: the significant role of domestic animals in transmission of human microsporidiosis

https://doi.org/10.1016/j.rvsc.2020.09.030Get rights and content

Highlights

  • Enterocytozoon bieneusi is commonly distributed in domestic animals worldwide.

  • E. bieneusi has a different genotype distribution pattern in various species of domestic animals.

  • The role of domestic animals in zoonotic transmission of E. bieneusi was assessed.

  • Host specificity and zoonotic potential of E. bieneusi vary among phylogenetic groups.

  • Additional genotyping data obtained from multiple hosts in the same areas are needed.

Abstract

Enterocytozoon bieneusi is an obligate intracellular fungus-like parasite with high genetic diversity among mammalian and avian hosts. Based on polymorphism analysis of the ribosomal internal transcribed spacer (ITS), nearly 500 genotypes were identified within E. bieneusi. Those genotypes form several genetic groups that exhibit phenotypic differences in host specificity and zoonotic potential and probably have varying public health implications. Some of the genotypes in Group 1 (e.g., D, EbpC, and Type IV) and Group 2 (e.g., BEB4, BEB6, I, and J) are the most common ones that infect a variety of hosts including humans and thus are of public health importance. By contrast, those genotypes in other genetic groups (Groups 3–11) are mostly restricted to the hosts from which they were originally isolated, which would have unknown or limited impacts on public health. Advances on diagnosis and molecular typing of E. bieneusi are introduced in this review. Genotype distribution pattern of E. bieneusi in major domestic animal groups (pigs, cattle, sheep, goats, cats, and dogs), the role of those animals in zoonotic transmission of microsporidiosis, and food and water as potential vehicles for transmission are interpreted here as well. This review highlights the importance of including more genetic or epidemiological data obtained in the same geographical areas and using more reliable genetic markers to analyze the actual extent of host specificity in E. bieneusi, for the purpose of fully appreciating zoonotic risks of those domestic animals in close contacts with men and enhancing our understanding of the modes of transmission.

Introduction

Nearly 1,500 microsporidian species in over 200 genera have thus far been reported in a broad range of eukaryotes; most of those species appear well adapted to specific hosts but some have wide host ranges and present serious public health problems (Stentiford et al., 2016; Vavra and Lukes, 2013; Weiss and Becnel, 2014). Microsporidia form an ancestral branch within fungi (Heitman, 2010; James et al., 2013), recent genomic evidences support the organisms might be true fungi (Quandt et al., 2017). Of the 17 microsporidian species known as human pathogens, Enterocytozoon bieneusi is the most prevalent one that infects the gastrointestinal tract and causes parasitic diarrhea mainly in immune-deficient individuals (Li et al., 2019c; Matos et al., 2012; Weiss and Becnel, 2014). E. bieneusi has strong host dependence probably due to its reduced genome (~6 megabases in length estimated) lacking key genes necessary for self-energy production (Akiyoshi et al., 2009; Keeling and Corradi, 2011; Keeling et al., 2010). E. bieneusi is typically transmitted through the fecal-oral route; the lifecycle of this organism begins with the ingestion of environmentally resistant spores by susceptible human and animal subjects, followed by host cell invasion via the cross-pierced polar tube, intracellular replication, mature spore release, and a new circulation in uninfected host (Li et al., 2019c). The repeated detection of E. bieneusi in humans, nonhuman mammals, birds, food, and water implies the likelihood of occurrence of zoonotic, foodborne, and waterborne transmission (Decraene et al., 2012; Galvan et al., 2013; Guo et al., 2014; Hu et al., 2014; Huang et al., 2017; Jedrzejewski et al., 2007; Lee, 2008; Li et al., 2012; Li et al., 2019c; Santin and Fayer, 2011).

Basic researches on biology and pathogenicity of E. bieneusi have been greatly hampered due to its quite small-sized structure and the lack of sustainable in vitro culture method (Visvesvara, 2002), while there have been important global advances in molecular epidemiology in recent years. Those concerned with genomic DNA isolation, PCR amplification, polymorphic analysis of the amplicons, genotype determination, and phylogenetic analysis of E. bieneusi strains from various sources are particularly notable. This review briefly introduces the achievements on diagnosis and molecular typing of E. bieneusi, summarizes genotypes identified thus far in major domestic animal groups around the world, examines phylogenetic patterns and phenotypic profiles of those genotypes, and evaluates the role of those usual animals in zoonotic transmission of this ubiquitous parasite.

Section snippets

Diagnosis

The most recognizable life stage of E. bieneusi is the spore, yet diagnosis by routine microscopy is often missed as the spore is very small in size, around 1μm. In addition, the identification of E. bieneusi spores in stools is often affected by interfering substances such as debris, bacteria, fungi, and some other common mammalian microsporidia, notably Encephalitozoon spp. (Garcia, 2002; Schwartz et al., 1994; Weber et al., 1994). Several staining techniques have been developed to diagnose

Genotyping and phylogeny

In contrast to traditional techniques, molecular typing of microorganisms generally allows a more detailed and comprehensive analysis of the structure of microbe populations. A more precise identification of microbe strains and a more reliable assessment of their prevalence and geographical distribution in various hosts became possible. Comparison of DNA sequences through phylogenetic analysis makes possible to assess the genetic relationships between isolates. As mentioned above, early

Potential zoonotic origins

Both domestic and wild mammals can host human-pathogenic E. bieneusi genotypes (Li et al., 2019c). Although the focus of this review is on the former, the role of wildlife in the epidemiology of E. bieneusi should not be neglected. In many cases, domestic and wild animals share the same outdoor areas in both urban and rural environments, so that interspecies transmission of zoonotic genotypes may occur during their interactions with each other (Dashti et al., 2020). Livestock animals including

Potential transmission routes

A foodborne outbreak of E. bieneusi infection in persons visiting a hotel in Sweden was inferred to be associated with consumption of cheese sandwiches and salad; the isolates were later typed as genotype C (Decraene et al., 2012). Genotype C may originate from fecal pollution by humans as its host range has so far been exclusively confined to humans as evaluated before (Li et al., 2019c). The occurrence of E. bieneusi spores in retail fresh food produce like berries, sprouts, and green-leafed

Conclusions and perspectives

In conclusion, zoonotic transmissibility of E. bieneusi has been explained in detail here, and the possible presence of foodborne and waterborne spore dispersal has been discussed as well. The distribution preference, phylogenetic pattern, and host specificity of E. bieneusi genotypes and the associated zoonotic implications varied a lot among different species of domestic animals (Fig. 1). Almost all the domestic animals investigated here can be the hosts of three of the most important

Acknowledgements

This work is funded by the Natural Science Fund of Heilongjiang Province for Excellent Young Scholars, grant number YQ2020C010.

References (204)

  • S. Jamshidi et al.

    Microsporidia in household dogs and cats in Iran; a zoonotic concern

    Vet. Parasitol.

    (2012)
  • J. Jurankova et al.

    Enterocytozoon bieneusi in bovine viral diarrhea virus (BVDV) infected and noninfected cattle herds

    Res. Vet. Sci.

    (2013)
  • M.A. Lallo et al.

    Encephalitozoon and Enterocytozoon (Microsporidia) spores in stool from pigeons and exotic birds: microsporidia spores in birds

    Vet. Parasitol.

    (2012)
  • W. Li et al.

    Prevalence and genetic characteristics of Cryptosporidium, Enterocytozoon bieneusi and Giardia duodenalis in cats and dogs in Heilongjiang province, China

    Vet. Parasitol.

    (2015)
  • W. Li et al.

    Host specificity of Enterocytozoon bieneusi and public health implications

    Trends Parasitol.

    (2019)
  • W. Li et al.

    Potential impacts of host specificity on zoonotic or interspecies transmission of Enterocytozoon bieneusi

    Infect. Genet. Evol.

    (2019)
  • J. Li et al.

    Occurrence, molecular characterization and predominant genotypes of Enterocytozoon bieneusi in dairy cattle in Henan and Ningxia, China

    Parasit. Vectors

    (2016)
  • N. Abe et al.

    Molecular survey of Enterocytozoon bieneusi in a Japanese porcine population

    Vector Borne and Zoonotic Dis.

    (2010)
  • N. Abe et al.

    Molecular evidence of Enterocytozoon bieneusi in Japan

    J. Vet. Med. Sci.

    (2009)
  • I. Accoceberry et al.

    Production of monoclonal antibodies directed against the microsporidium Enterocytozoon bieneusi

    J. Clin. Microbiol.

    (1999)
  • D.E. Akiyoshi et al.

    Genomic survey of the non-cultivatable opportunistic human pathogen, Enterocytozoon bieneusi

    PLoS Pathog.

    (2009)
  • O. Alfa Cisse et al.

    Evaluation of an immunofluorescent-antibody test using monoclonal antibodies directed against Enterocytozoon bieneusi and Encephalitozoon intestinalis for diagnosis of intestinal microsporidiosis in Bamako (Mali)

    J. Clin. Microbiol.

    (2002)
  • R. Banerjee et al.

    Recent advances in nanoparticle-based lateral flow immunoassay as a point-of-care diagnostic tool for infectious agents and diseases

    Analyst

    (2018)
  • A. Bart et al.

    Frequent occurrence of human-associated microsporidia in fecal droppings of urban pigeons in amsterdam, the Netherlands

    Appl. Environ. Microbiol.

    (2008)
  • L. Ben Ayed et al.

    Survey and genetic characterization of wastewater in Tunisia for Cryptosporidium spp., Giardia duodenalis, Enterocytozoon bieneusi, Cyclospora cayetanensis and Eimeria spp

    J. Water Health

    (2012)
  • J.D. Bishop et al.

    Sensitivity enhancement in lateral flow assays: a systems perspective

    Lab Chip

    (2019)
  • Breitenmoser, A.C., Mathis, A., Burgi, E., Weber, R., Deplazes, P., 1999. High prevalence of Enterocytozoon bieneusi in...
  • M.A. Buckholt et al.

    Prevalence of Enterocytozoon bieneusi in swine: an 18-month survey at a slaughterhouse in Massachusetts

    Appl. Environ. Microbiol.

    (2002)
  • I. Bukreyeva et al.

    Enterocytozoon bieneusi microsporidiosis in stem cell transplant recipients treated with fumagillin1

    Emerg. Infect. Dis.

    (2017)
  • U. Cetinkaya et al.

    Investigation of the presence of Encephalitozoon intestinalis and Enterocytozoon bieneusi in bone marrow transplant patients by IFA-MAbs method

    Mikrobiyoloji Bulteni

    (2015)
  • R.M. Chalmers et al.

    Comparison of diagnostic sensitivity and specificity of seven Cryptosporidium assays used in the UK

    J. Med. Microbiol.

    (2011)
  • Y. Chang et al.

    Molecular characterization of Giardia duodenalis and Enterocytozoon bieneusi isolated from Tibetan sheep and Tibetan goats under natural grazing conditions in Tibet

    J. Eukaryot. Microbiol.

    (2020)
  • H.W. Cheng et al.

    Municipal wastewater treatment plants as removal systems and environmental sources of human-virulent microsporidian spores

    Parasitol. Res.

    (2011)
  • H.W. Cheng et al.

    Determining potential indicators of Cryptosporidium oocysts throughout the wastewater treatment process

    Water Sci. Technol.

    (2012)
  • S. Coupe et al.

    Detection of Cryptosporidium, Giardia and Enterocytozoon bieneusi in surface water, including recreational areas: a one-year prospective study

    FEMS Immunol. Med. Microbiol.

    (2006)
  • D. Dado et al.

    Detection of zoonotic intestinal parasites in public parks of Spain. Potential epidemiological role of microsporidia

    Zoonoses Public Health

    (2012)
  • A. Dashti et al.

    Occurrence and genetic diversity of Enterocytozoon bieneusi (Microsporidia) in owned and sheltered dogs and cats in Northern Spain

    Parasitol. Res.

    (2019)
  • A. Dashti et al.

    Enterocytozoon bieneusi (Microsporidia): Identification of novel genotypes and evidence of transmission between sympatric wild boars (Sus scrofa ferus) and Iberian pigs (Sus scrofa domesticus) in Southern Spain

    Transbound. Emerg. Dis.

    (2020)
  • F. David et al.

    Detection and species identification of intestinal microsporidia by polymerase chain reaction in duodenal biopsies from human immunodeficiency virus-infected patients

    J. Infect. Dis.

    (1996)
  • V. Decraene et al.

    First reported foodborne outbreak associated with microsporidia, Sweden, October 2009

    Epidemiol. Infect.

    (2012)
  • M. Delrobaei et al.

    Molecular detection and genotyping of intestinal microsporidia from stray dogs in Iran

    Iran. J. Parasitol.

    (2019)
  • B. Dengjel et al.

    Zoonotic potential of Enterocytozoon bieneusi

    J. Clin. Microbiol.

    (2001)
  • P. Deplazes et al.

    Molecular epidemiology of Encephalitozoon cuniculi and first detection of Enterocytozoon bieneusi in faecal samples of pigs

    J. Eukaryot. Microbiol.

    (1996)
  • S.E. Dowd et al.

    Confirmation of the human-pathogenic microsporidia Enterocytozoon bieneusi, Encephalitozoon intestinalis, and Vittaforma corneae in water

    Appl. Environ. Microbiol.

    (1998)
  • R. Fayer et al.

    Enterocytozoon bieneusi in mature dairy cattle on farms in the eastern United States

    Parasitol. Res.

    (2007)
  • R. Fayer et al.

    Detection of concurrent infection of dairy cattle with Blastocystis, Cryptosporidium, Giardia, and Enterocytozoon by molecular and microscopic methods

    Parasitol. Res.

    (2012)
  • D.P. Fedorko et al.

    Identification of microsporidia in stool specimens by using PCR and restriction endonucleases

    J. Clin. Microbiol.

    (1995)
  • Y. Feng et al.

    Zoonotic potential and molecular epidemiology of Giardia species and giardiasis

    Clin. Microbiol. Rev.

    (2011)
  • Y. Feng et al.

    Development of a multilocus sequence typing tool for high-resolution genotyping of Enterocytozoon bieneusi

    Appl. Environ. Microbiol.

    (2011)
  • Y. Feng et al.

    Prevalence and genotypic identification of Cryptosporidium spp., Giardia duodenalis and Enterocytozoon bieneusi in pre-weaned dairy calves in Guangdong, China

    Parasit. Vectors

    (2019)
  • Cited by (0)

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