Molecular epidemiology of Blastocystis sp. in dogs housed in Italian rescue shelters

  • Alessia Libera GazzonisEmail author
  • Marianna Marangi
  • Sergio Aurelio Zanzani
  • Luca Villa
  • Annunziata Giangaspero
  • Maria Teresa Manfredi
Protozoology - Original Paper


Blastocystis is a ubiquitous protozoan with a wide range of hosts. In humans, its presence has been associated with gastrointestinal disorders, although its role as a pathogen still needs to be elucidated. Until now, 17 Blastocystis subtypes (STs) have been identified, with ST1–ST4 the most commonly found in humans. Among domestic animals, the same STs reported in humans have been detected in dogs. An epidemiological survey on dog kennels was carried out to evaluate the prevalence of Blastocystis and the STs involved. Overall, 99 faecal samples were collected from the rescue shelters. Blastocystis detection was performed through conventional barcoding PCR targeting the 1800-bp SSU-rDNA, followed by sequencing and phylogenetic analysis. Blastocystis DNA was found in 21 faecal samples (21.2%), and all samples were successfully sequenced and identified as ST3 in a unique monophyletic group. The presence of Blastocystis was reported for the first time in dogs from Italy, with the identification of ST3, the subtype most commonly found in humans.


Blastocystis Subtypes Dog Zoonosis Molecular epidemiology Genotyping 



Authors are grateful to the shelters’ personnel and volunteers for their help in the sample collection.

Compliance with ethical standards

The collection of biological samples from live animals was performed in the respect of animal welfare according to current legislation. The study was conducted with the approval of each of the involved shelter and the Institutional Animal Care and Use Committee of Università degli Studi di Milano (Permission OPBA_34_2017).

Conflict of interest

The authors declare that they have no conflict of interest.


  1. Alfellani MA, Stensvold CR, Vidal-Lapiedra A, Onuoha ES, Fagbenro-Beyioku AF, Clark CG (2013) Variable geographic distribution of Blastocystis subtypes and its potential implications. Acta Trop 126:11–18. CrossRefGoogle Scholar
  2. Angelici MC, Nardis C, Scarpelli R, Ade P (2018) Blastocystis hominis transmission by non-potable water: a case report in Italy. New Microbiol 41:173–177Google Scholar
  3. Belleza MLB, Reyes JCB, Tongol-Rivera PN, Rivera WL (2016) Subtype analysis of Blastocystis sp. isolates from human and canine hosts in an urban community in the Philippines. Parasitol Int 65:291–294. CrossRefGoogle Scholar
  4. Boorom KF, Smith H, Nimri L, Viscogliosi E, Spanakos G, Parkar U, Li LH, Zhou XN, Ok UZ, Leelayoova S, Jones MS (2008) Oh my aching gut: irritable bowel syndrome, Blastocystis, and asymptomatic infection. Parasit Vectors 1:40. CrossRefGoogle Scholar
  5. Caradonna T, Marangi M, Del Chierico F, Ferrari N, Reddel S, Bracaglia G, Normanno G, Putignani L, Giangaspero A (2017) Detection and prevalence of protozoan parasites in ready-to-eat packaged salads on sale in Italy. Food Microbiol 67:67–75. CrossRefGoogle Scholar
  6. Chabé M, Lokmer A, Ségurel L (2017) Gut protozoa: friends or foes of the human gut microbiota? Trends Parasitol 33:925–934. CrossRefGoogle Scholar
  7. Chapman S, Thompson C, Wilcox A et al (2009) What is your diagnosis? Rectal scraping from a dog with diarrhea. Vet Clin Pathol 38:59–62. CrossRefGoogle Scholar
  8. Clark CG, van der Giezen M, Alfellani MA, Stensvold CR (2013) Recent developments in Blastocystis research. Adv Parasitol 82:1-32.
  9. Elwakil HS, Hewedi IH (2010) Pathogenic potential of Blastocystis hominis in laboratory mice. Parasitol Res 107:685–689. CrossRefGoogle Scholar
  10. Goe AM, Heard DJ, Easley JR, Weeden AL, Childress AL, Wellehan JF (2016) Blastocystis sp. and Blastocystis ratti in a Brazilian porcupine (Coendou prehensilis) with diarrhea. J Zoo Wildl Med 47:640–644. CrossRefGoogle Scholar
  11. Lee IL, Tan TC, Tan PC, Nanthiney DR, Biraj MK, Surendra KM, Suresh KG (2012) Predominance of Blastocystis sp. subtype 4 in rural communities, Nepal. Parasitol Res 110:1553–1562. CrossRefGoogle Scholar
  12. Leelayoova S, Rangsin R, Taamasri P, Naaglor T, Thathaisong U, Mungthin M (2004) Evidence of waterborne transmission of Blastocystis hominis. Am J Trop Med Hyg 70:658–662CrossRefGoogle Scholar
  13. Leelayoova S, Siripattanapipong S, Thathaisong U, Naaglor T, Taamasri P, Piyaraj P, Mungthin M (2008) Drinking water: a possible source of Blastocystis spp. subtype 1 infection in schoolchildren of a rural community in central Thailand. Am J Trop Med Hyg 79:401–406CrossRefGoogle Scholar
  14. Mattiucci S, Crisafi B, Gabrielli S, Paoletti M, Cancrini G (2016) Molecular epidemiology and genetic diversity of Blastocystis infection in humans in Italy. Epidemiol Infect 144:635–646. CrossRefGoogle Scholar
  15. Meloni D, Sanciu G, Poirier P, El Alaoui H, Chabé M, Delhaes L, Dei-Cas E, Delbac F, Luigi Fiori P, Di Cave D, Viscogliosi E (2011) Molecular subtyping of Blastocystis sp. isolates from symptomatic patients in Italy. Parasitol Res 109:613–619. CrossRefGoogle Scholar
  16. Moe KT, Singh M, Howe J, Ho LC, Tan SW, Chen XQ, Ng GC, Yap EH (1997) Experimental Blastocystis hominis infection in laboratory mice. Parasitol Res 83:319–325. CrossRefGoogle Scholar
  17. Nagel R, Cuttell L, Stensvold CR, Mills PC, Bielefeldt-Ohmann H, Traub RJ (2012) Blastocystis subtypes in symptomatic and asymptomatic family members and pets and response to therapy. Intern Med J 42:1187–1195. CrossRefGoogle Scholar
  18. Noël C, Dufernez F (2005) Molecular phylogenies of Blastocystis isolates from different hosts: implications for genetic diversity, identification of species, and zoonosis. J Clin Microbiol 43:348–355. CrossRefGoogle Scholar
  19. Osman M, Bories J, El Safadi D, Poirel MT, Gantois N, Benamrouz-Vanneste S, Delhaes L, Hugonnard M, Certad G, Zenner L, Viscogliosi E (2015) Prevalence and genetic diversity of the intestinal parasites Blastocystis sp. and Cryptosporidium spp. in household dogs in France and evaluation of zoonotic transmission risk. Vet Parasitol 214:167–170. CrossRefGoogle Scholar
  20. Pakandl M (1991) Occurrence of Blastocystis sp. in pigs. Folia Parasitol (Praha) 38:297–301Google Scholar
  21. Parkar U, Traub RJ, Vitali S, Elliot A, Levecke B, Robertson I, Geurden T, Steele J, Drake B, Thompson RC (2010) Molecular characterization of Blastocystis isolates from zoo animals and their animal-keepers. Vet Parasitol 169:8–17. CrossRefGoogle Scholar
  22. Paulos S, Köster PC, de Lucio A, Hernández-de-Mingo M, Cardona GA, Fernández-Crespo JC, Stensvold CR, Carmena D (2018) Occurrence and subtype distribution of Blastocystis sp. in humans, dogs and cats sharing household in northern Spain and assessment of zoonotic transmission risk. Zoonoses Public Health 65:993–1002. CrossRefGoogle Scholar
  23. Phillips BP, Zierdt CH (1976) Blastocystis hominis: pathogenic potential in human patients and in gnotobiotes. Exp Parasitol 39:358–364. CrossRefGoogle Scholar
  24. Quílez J, Sánchez-Acedo C, Clavel A, Causapé AC (1995) Occurrence of Blastocystis sp. in cattle in Aragón, northeastern Spain. Parasitol Res 81:703–705. CrossRefGoogle Scholar
  25. Ramírez JD, Sánchez LV, Bautista DC, Corredor AF, Flórez AC, Stensvold CR (2014) Blastocystis subtypes detected in humans and animals from Colombia. Infect Genet Evol 22:223–228. CrossRefGoogle Scholar
  26. Ramírez JD, Sánchez A, Hernández C, Flórez C, Bernal MC, Giraldo JC, Reyes P, López MC, García L, Cooper PJ, Vicuña Y, Mongi F, Casero RD (2016) Geographic distribution of human Blastocystis subtypes in South America. Infect Genet Evol 41:32–35. CrossRefGoogle Scholar
  27. Roberts T, Barratt J, Harkness J, Ellis J, Stark D (2011) Comparison of microscopy, culture, and conventional polymerase chain reaction for detection of Blastocystis sp. in clinical stool samples. Am J Trop Med Hyg 84:308–312. CrossRefGoogle Scholar
  28. Ruaux CG, Stang BV (2014) Prevalence of Blastocystis in shelter-resident and client-owned companion animals in the US Pacific Northwest. PLoS One 16;9(9):e107496.
  29. Scicluna SM, Tawari B, Clark CG (2006) DNA barcoding of Blastocystis. Protist 157:77–85. CrossRefGoogle Scholar
  30. Spanakos G, Papadogiannakis E, Kontos V, Menounos P, Velonakis E, Koutis C, Vakalis N (2011) Molecular screening for Blastocystis sp. in canine faecal samples in Greece. J Hell Vet Med Soc 62:216–220. CrossRefGoogle Scholar
  31. Stensvold CR, Suresh GK, Tan KSW, Thompson RC, Traub RJ, Viscogliosi E, Yoshikawa H, Clark CG (2007) Terminology for Blastocystis subtypes - a consensus. Trends Parasitol 23:93–96. CrossRefGoogle Scholar
  32. Stensvold CR, Lewis HC, Hammerum AM, Porsbo LJ, Nielsen SS, Olsen KE, Arendrup MC, Nielsen HV, Mølbak K (2009a) Blastocystis: unravelling potential risk factors and clinical significance of a common but neglected parasite. Epidemiol Infect 137:1655–1663. CrossRefGoogle Scholar
  33. Stensvold CR, Alfellani MA, Nørskov-Lauritsen S, Prip K, Victory EL, Maddox C, Nielsen HV, Clark CG (2009b) Subtype distribution of Blastocystis isolates from synanthropic and zoo animals and identification of a new subtype. Int J Parasitol 39:473–479. CrossRefGoogle Scholar
  34. Stensvold CR (2013) Comparison of sequencing (barcode region) and sequence-tagged-site PCR for Blastocystis subtyping. J Clin Microbiol 51:190–194. CrossRefGoogle Scholar
  35. Stensvold CR, Clark CG (2016) Current status of Blastocystis: a personal view. Parasitol Int 65:763–771. CrossRefGoogle Scholar
  36. Tan KSW (2004) Blastocystis in humans and animals: new insights using modern methodologies. Vet Parasitol 126:121–144. CrossRefGoogle Scholar
  37. Tan KSW (2008) New insights on classification, identification, and clinical relevance of Blastocystis spp. Clin Microbiol Rev 21:639–665. CrossRefGoogle Scholar
  38. Wang W, Cuttell L, Bielefeldt-Ohmann H, Inpankaew T, Owen H, Traub RJ (2013) Diversity of Blastocystis subtypes in dogs in different geographical settings. Parasit Vectors 6:1–5. CrossRefGoogle Scholar
  39. Wang W, Owen H, Traub RJ, Cuttell L, Inpankaew T, Bielefeldt-Ohmann H (2014) Molecular epidemiology of Blastocystis in pigs and their in-contact humans in Southeast Queensland, Australia, and Cambodia. Vet Parasitol 203:264–269. CrossRefGoogle Scholar
  40. Zanzani SA, Epis S, Bandi C, Manfredi MT (2014a) What is your diagnosis? Fecal smear stained with Lugol’s solution and Giemsa from a cynomolgus macaque (Macaca fascicularis) presenting with liquid diarrhea. Vet Clin Pathol 43:293–294. CrossRefGoogle Scholar
  41. Zanzani SA, Di Cerbo AR, Gazzonis AL, Genchi M, Rinaldi L, Musella V, Cringoli G, Manfredi MT (2014b) Canine fecal contamination in a metropolitan area (Milan, North-Western Italy): prevalence of intestinal parasites and evaluation of health risks. Sci World J 132361:1–6. CrossRefGoogle Scholar
  42. Zanzani SA, Gazzonis AL, Scarpa P, Berrilli F, Manfredi MT (2014c) Intestinal parasites of owned dogs and cats from metropolitan and micropolitan areas: prevalence, zoonotic risks, and pet owner awareness in northern Italy. Biomed Res Int 696508.
  43. Zanzani SA, Gazzonis AL, Epis S, Manfredi MT (2016) Study of the gastrointestinal parasitic fauna of captive non-human primates (Macaca fascicularis). Parasitol Res 115:307–312. CrossRefGoogle Scholar

Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Veterinary MedicineUniversità degli Studi di MilanoMilanItaly
  2. 2.Department of Science of Agriculture, Food and EnvironmentUniversity of FoggiaFoggiaItaly

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