Jesús Martínez-Sotelo, Biologist in training, Facultad de Ciencias de la Universidad Autónoma del Estado de México (Carretera Toluca-Ixtlahuaca Km. 15.5, 50200, Toluca, Estado de México, México); iD ORCID:; e-mail:
Jessica Mariana Sánchez-Jasso, MSc, Researcher at the Institute for Biodiversity Research, Development and Sustainability. iBIRDS A.C., México (San Agustín Berros s/n, 50960 Villa Victoria, Estado de México, Mexico); iD ORCID:; e-mail:
Salvador Ibarra-Zimbrón, MSc, Director of Servicios Veterinarios C&S., México (Álamos #252 Col. Lomas Altas, 50090, Toluca, México); iD ORCID:; e-mail:
Petra Sánchez-Nava, PhD, Professor and Researcher at Laboratorio de Sistemas Biosustentables, Facultad de Ciencias (Universidad Autónoma del Estado de México. Carretera Toluca-Ixtlahuaca Km. 15.5, 50200, Toluca, Estado de México, México); iD ORCID:; email:

Reference to article

Martínez-Sotelo J., Sánchez-Jasso J.M., Ibarra-Zimbrón S., Sánchez-Nava P. 2022. Zoonotic intestinal parasites in free-ranging dogs (Canis lupus familiaris): a risk to public health in a Mexican Protected Area. Nature Conservation Research 7(2): 21–31.

Section Research articles

Domestic dogs (Canis lupus familiaris) have been in contact with humans for thousands of years, playing an important role in societies. Nonetheless, the lack of responsible ownership has contributed to the transition from companion dogs to free-ranging or feral dogs that can be reservoirs of zoonotic parasites. Our goal was to identify zoonotic intestinal parasites in free-ranging dogs in a Mexican Protected Area. A total of 132 scat samples from free-ranging dogs were collected and examined using the Faust flotation technique. We identified a total of nine parasite species, four platyhelminthes, and five nematodes. Eight of nine identified parasite are zoonotic. The most frequent zoonotic parasites are Ancylostoma caninum and Ascaris spp. (19.7% each) followed by Toxascaris leonina (17.4%) and Uncinaria stenocephala (7.6%). The least frequent are Dipylidium caninum (2.2%), Capillaria spp., Hymenolepis diminuta, and Hymenolepis nana (0.75% each). This study provides the first description of intestinal zoonotic parasites richness in free-ranging dogs within a Mexican Protected Area. The presence of zoonotic parasites in canine scats represents a high risk to public health, mainly for the transmission of some species through cutaneous and visceral migrans larvae, especially in infants and kids. We recommend specific measures to prevent, control and mitigate the presence of free-ranging dogs in Protected Areas.


invasive alien species, Mexico, Nevado de Toluca, public park, zoonosis

Artice information

Received: 24.12.2021. Revised: 02.03.2022. Accepted: 18.03.2022.

The full text of the article

Aragón-Pech R.A., Ruiz-Piña H.A., Rodríguez-Vivas R.I., Cuxim-Koyoc A.D., Reyes-Novelo E. 2018. Prevalence, Abundance and Intensity of Eggs and Oocysts of Gastrointestinal Parasites in the Opossum Didelphis virginiana Kerr, 1792 in Yucatan, Mexico. Helminthologia 55(2): 119–126. DOI: 10.2478/helm-2018-0008
Belsare A., Vanak A.T. 2020. Modelling the challenges of managing free-ranging dog populations. Scientific Reports 10(1): 18874. DOI: 10.1038/s41598-020-75828-6
Bojar H., Kłapeć T. 2012. Contamination of soil with eggs of geohelminths in recreational areas in the Lublin region of Poland. Annals of Agricultural Environmental Medicine 19(2): 267–270.
Bowman D.D. 2011. Georgis: Parasitología para Veterinarios. Spain: Elsevier. 464 p.
Bush A.O., Lafferty K.D., Lotz J.M., Shostak A.W. 1997. Parasitology meets ecology on its own terms: Margolis et al. Revisited. Journal Parasitology 83(4): 575–583. DOI: 10.2307/3284227
Carrasco-Román E., Medina J.P., Salgado-Miranda C., Soriano-Vargas E., Sánchez-Jasso J.M. 2021. Contributions on the diet of free-ranging dogs (Canis lupus familiaris) in the Nevado de Toluca Flora and Fauna Protection Area, Estado de México, Mexico. Revista Mexicana de Biodiversidad 92: e9234952. DOI: 10.22201/ib.20078706e.2021.92.3495
Clench H.K. 1979. How to make regional lists of butterflies: Some thoughts. Journal of the Lepidopterists' Society 33(4): 216–231.
Cordero del Campillo M., Rojo V.F.A., Martínez F.A.R., Sánchez A.M.C., Hernández R.S., Navarrete L.I., Diez B.P., Quiroz R.H., Carvalho V.M. 1999. Parasitología Veterinaria. Madrid: McGraw-Hill Interamericana. 968 p.
CONABIO. 2010. Comisión Nacional para el Conocimiento y Uso de la Biodiversidad. Estrategia nacional de especies invasoras de México. Prevención, Control y Erradicación. Available from
Curi N.H.A., Paschoal A.M.O., Massara R.L., Santos H.A., Guimarães M.P., Passamani M., Chiarello A.G. 2017. Risk factors for gastrointestinal parasite infections of dogs living around protected areas of the Atlantic Forest: implications for human and wildlife health. Brazilian Journal of Biology 77(2): 388–395. DOI: 10.1590/1519-6984.19515
Dantas-Torres F., Otranto D. 2014. Dogs, cats, parasites, and humans in Brazil: opening the black box. Parasites and Vectors 7(1): 22. DOI: 10.1186/1756-3305-7-22
DOF. 2016a. Acuerdo por el que se determina la Lista de las Especies Exóticas Invasoras para México. Diario Oficial de la Federación. Available from
DOF. 2016b. Resumen del programa de manejo del Área Natural Protegida con la categoría de Área de Protección de Flora y Fauna Nevado de Toluca. Diario Oficial de la Federación. Available from
Doherty T.S., Dickman C.R., Glen A.S., Newsome T.M., Nimmo D.G., Ritchie E.G., Vanak A.T., Wirsing A.J. 2017. The global impacts of domestic dogs on threatened vertebrates. Biological Conservation 210(Part A): 56–59. DOI: 10.1016/j.biocon.2017.04.007
Eguía-Aguilar P., Cruz-Reyes A., Martínez-Maya J.J. 2005. Ecological analysis and description of the intestinal helminths present in dogs in Mexico City. Veterinary Parasitology 127(2): 139–146. DOI: 10.1016/j.vetpar.2004.10.004
Else K.J., Keiser J., Holland C.V., Grencis R.K., Sattelle D.B., Fujiwara R.T., Bueno L.L., Asaolu S.O., Sowemimo O.A., Cooper P.J. 2020. Whipworm and roundworm infections. Nature Reviews Disease Primers 6(1): 44. DOI: 10.1038/s41572-020-0171-3
Enriquez G.F., Macchiaverna N.P., Argibay H.D., Arias L.L., Farber M., Gürtler R.E., Cardinal M.V., Garbossa G. 2019. Polyparasitism and zoonotic parasites in dogs from a rural area of the Argentine Chaco. Veterinary Parasitology: Regional Studies and Reports 16: 100287. DOI: 10.1016/j.vprsr.2019.100287
Erickson A.B. 1944. Helminths of Minnesota Canidae in Relation to Food Habits, and a Host List and Key to the Species Reported from North America. American Midland Naturalist 32(2): 358–372. DOI: 10.2307/2421306
ESRI. 2013. ESRI – Environmental Systems Research Institute. Available from
Fontanarrosa M.F., Vezzani D., Basabe J., Eiras D.F. 2006. An epidemiological study of gastrointestinal parasites of dogs from Southern Greater Buenos Aires (Argentina): age, gender, breed, mixed infections, and seasonal and spatial patterns. Veterinary Parasitology 136(3–4): 283–295. DOI: 10.1016/j.vetpar.2005.11.012
Foreyt W.J. 2001. Veterinary Parasitology. Reference Manual. Ames, Iowa: Blackwell Publishing Professional. 256 p.
García E. 1981. Modificaciones al Sistema de Clasificación Climática de Köppen: para adaptarlos a las condiciones de la República Mexicana. México: Instituto de Geografía, UNAM. 252 p.
Gillis-Germitsch N., Müller S., Gori F., Schnyder M. 2020. Capillaria boehmi (syn. Eucoleus boehmi): Challenging treatment of a rarely diagnosed nasal nematode in dogs and high prevalence in Swiss foxes. Veterinary Parasitology 281:109103. DOI: 10.1016/j.vetpar.2020.109103
GISD. 2010. Canis lupus (mammal). In: The Global Invasive species database. Available from
Guardone L., Deplazes P., Macchioni F., Magi M., Mathis A. 2013. Ribosomal and mitochondrial DNA analysis of Trichuridae nematodes of carnivores and small mammals. Veterinary Parasitology 197(1–2): 364–369. DOI: 10.1016/j.vetpar.2013.06.022
Guedes J.J.M., Assis C.L., Feio R.N., Quintela F.M. 2021. The impacts of domestic dogs (Canis familiaris) on wildlife in two Brazilian hotspots and implications for conservation. Animal Biodiversity and Conservation 44(1): 45–58. DOI: 10.32800/abc.2021.44.0045
Hammer Ø., Harper D., Ryan P. 2001. PAST: Paleontological Statistics Software Package for Education and Data Analysis. Palaeontologia Electronica 4(1): 1–9.
Hawdon J.M., Wise K.A. 2021. Ancylostoma caninum and Other Canine Hookworms. In: C. Strube, H. Mehlhorn (Eds.): Dog Parasites Endangering Human Health. Cham: Springer. P. 147–193.
Hendrix C.M. 1998. Diagnostic Veterinary Parasitology. St. Louis: Mosby, Inc. 321 p.
Hernández-Camacho N., Pineda-López R., López-González C.A., Jones R.W. 2011. Nematodes parasites of the gray fox (Urocyon cinereoargenteus Schreber, 1775) in the seasonally dry tropical highlands of central Mexico. Parasitology Research 108(6): 1425–1429. DOI: 10.1007/s00436-010-2191-5
Hiestand S.J., Nielsen C.K., Jiménez F.A. 2014. Epizootic and zoonotic helminths of the bobcat (Lynx rufus) in Illinois and a comparison of its helminth component communities across the American Midwest. Parasite 21: 4. DOI: 10.1051/parasite/2014005
INEGI. 2010. Localidades de la República Mexicana. México, 2010. Comisión Nacional para el Conocimiento y Uso de la Biodiversidad. México, D.F.: Instituto Nacional de Estadística y Geografía.
Jiménez-Valverde A., Hortal J. 2003. Las curvas de acumulación de especies y la necesidad de evaluar la calidad de los inventarios biológicos. Revista Ibérica de Aracnología 8: 151–160.
Leles D., Gardner S.L., Reinhard K., Iñiguez A., Araujo A. 2012. Are Ascaris lumbricoides and Ascaris suum a single species? Parasites and Vectors 5: 42. DOI: 10.1186/1756-3305-5-42
MacPherson C.N.L. 2005. Human behaviour and the epidemiology of parasitic zoonoses. International Journal of Parasitology 35(11–12): 1319–1331. DOI: 10.1016/j.ijpara.2005.06.004
Martínez-Aquino A., Salgado-Maldonado G., Aguilar-Aguilar R., Cabañas-Carranza G., Ortega-Olivares M.P. 2004. Helminth parasites of Chapalichthys encaustus (Pisces: Goodeidae), an endemic freshwater fish from Lake Chapala, Jalisco, Mexico. Journal of Parasitology 90(4): 889–890. DOI: 10.1645/GE-255R
Mehlhorn H. 2016. Animal Parasites. Diagnosis, Treatment, Prevention. Cham: Springer International Publishing. 719 p.
Michalczyk M., Sokół R., Gałęcki R. 2019. Internal parasites infecting dogs in rural areas. Annals of Parasitology 65(2): 151–158. DOI: 10.17420/ap6502.195
Midha A., Ebner F., Schlosser-Brandenburg J., Rausch S., Hartmann S. 2021. Trilateral relationship: Ascaris, microbiota, and host cells. Trends in Parasitology 37(3): 251–262. DOI: 10.1016/
Mönning H.O. 1950. Veterinary Helminthology and Entomology. The Diseases of Domesticated Animals caused by Helminth and Arthropod Parasites. Baltimore: The Williams & Wilkins Company. 427 p.
Nesbitt W.H. 1975. Ecology of a feral dog pack on a wildlife refuge. In: M.W. Fox (Ed.): The wild canids: their systematics, behavioural ecology and evolution. New York: Van Nostrand Reinhold. P. 391–395.
Nobis G. 1979. Der älteste Haushunde lebte vor 14000 Jahren. Umschau 79: 610.
Nguyen T., Clark N., Jones M.K., Herndon A., Mallyon J., Magalhaes R.J.S., Abdullah S. 2021. Perceptions of dog owners towards canine gastrointestinal parasitism and associated human health risk in Southeast Queensland. One Health 12: 100226. DOI: 10.1016/j.onehlt.2021.100226
Ortega-Pacheco A., Torres-Acosta J.F., Alzina-López A., Gutiérrez-Blanco E., Bolio-González M.E., Aguilar-Caballero A.J., Rodríguez-Vivas R.I., Gutiérrez-Ruiz E., Acosta-Viana K.Y., Guzmán-Marín E., Rosado-Aguilar A., Jiménez-Coello M. 2015. Parasitic Zoonoses in Humans and Their Dogs from a Rural Community of Tropical Mexico. Journal of Tropical Medicine 2015: 481086. DOI: 10.1155/2015/481086
Othman R.A., Abuseir S. 2021. The Prevalence of Gastrointestinal Parasites in Native Dogs in Palestine. Iranian Journal of Parasitology 16(3): 435–442. DOI: 10.18502/ijpa.v16i3.7097
Paschoal A.M.O., Massara R.L., Santos J.L., Chiarello A.G. 2012. Is the domestic dog becoming an abundant species in the Atlantic Forest? A study case in southeastern Brazil. Mammalia 76(1): 67–76. DOI: 10.1515/mammalia-2012-0501
Pullan L.R., Smith L.J., Jasrasia R., Brooker J.S. 2014. Global numbers of infection and disease burden of soil transmitted helminth infections in 2010. Parasites and Vectors 7: 37. DOI: 10.1186/1756-3305-7-37
Raether W., Hänel H. 2003. Epidemiology, clinical manifestations and diagnosis of zoonotic cestode infections: an update. Parasitology Research 91(5): 412–438. DOI: 10.1007/s00436-003-0903-9
Rahman M.T., Sobur M.A., Islam M.S., Ievy S., Hossain M.J., El Zowalaty M.E., Rahman A.T., Ashour H.M. 2020. Zoonotic Diseases: Etiology, Impact, and Control. Microorganisms 8(9): 1405. DOI: 10.3390/microorganisms8091405
Rankin J.S. 1946. Helminth Parasites of Birds and Mammals in Western Massachusetts. American Midland Naturalist 35(3): 756–768. DOI: 10.2307/2421556
Romero Núñez C., Mendoza Martínez G.D., Bustamante L.P., Crosby Galván M.M., Ramírez Durán N. 2011. Presencia y viabilidad de Toxocara spp en suelos de parques públicos, jardines de casas y heces de perros en Nezahualcóyotl, México. Revista Científica 21(3): 195–201.
Sánchez-Jasso J.M., Cebrián-Abellán F. 2015. Turismo de naturaleza en áreas protegidas de México. Una propuesta de conservación, aprovechamiento y desarrollo local en el Nevado de Toluca. Cuadernos de Turismo 36: 339–365. DOI: 10.6018/turismo.36.231041
Sánchez-Jasso J.M., Aguilar-Miguel X., Medina-Castro J.P., Sierra-Domínguez G. 2013. Riqueza específica de vertebrados en un bosque reforestado del Parque Nacional Nevado de Toluca, México. Revista Mexicana de Biodiversidad 84(1): 360–373. DOI: 10.7550/rmb.29473
Schoeb T.R., Cartner S.C., Baker R.A., Gerrity L.W. 2007. Parasites of rabbits. In: D.G. Baker (Ed.): Flynn's parasites of laboratory animals. Ames, Iowa: John Wiley & Sons. P. 451–499.
Schell S.C. 1962. Parasitology laboratory manual. New York: John Wiley & Sons, Inc. P. 96.
Scott M.D., Causey K. 1973. Ecology of feral dogs in Alabama. Journal of Wildlife Management 37(3): 253–265. DOI: 10.2307/3800116
Sélem-Salas C., MacSwiney M., Hernández-Betancourt S. 2011. Aves y mamíferos. In: Z.F. Bautista (Ed.): Técnicas de muestreo para manejadores de recursos naturales. México: Universidad Nacional Autónoma de México. P. 351–388.
Sepúlveda M., Pelican K., Cross P., Eguren A., Singer R. 2015. Fine-scale movements of rural free-ranging dogs in conservation areas in the temperate rainforest of the coastal range of southern Chile. Mammalian Biology 80(4): 290–297. DOI: 10.1016/j.mambio.2015.03.001
Shalaby H.A., Abdel-Shafy S., Derbala A.A. 2010. The role of dogs in transmission of Ascaris lumbricoides for humans. Parasitology Research 106(5): 1021–1026. DOI: 10.1007/s00436-010-1755-8
Shepherd C., Wangchuk P., Loukas A. 2018. Of dogs and hookworms: man's best friend and his parasites as a model for translational biomedical research. Parasites & Vectors 11(1): 59. DOI: 10.1186/s13071-018-2621-2
Siyadatpanah A., Gholami S., Daryani A., Sarvi S., Sharif M., Seguel M., Boundenga L., Amouei A., Pagheh A.S., Rahimi M.T., Hosseini S.A., Anvari D. 2019. The Prevalence of Intestinal Helminths in Free-Ranging Canids of Mazandaran, Northern Iran. Iranian Journal of Parasitology 14(4): 563–571.
Sprenger L.K., Green K.T., Molento M.B. 2014. Geohelminth contamination of public areas and epidemiological risk factors in Curitiba, Brazil. Brazilian Journal of Veterinary Parasitology 23(1): 69–73. DOI: 10.1590/s1984-29612014009
Soriano S.V., Pierangeli N.B., Roccia I., Bergagna H.F., Lazzarini L.E., Celescinco A., Saiz M.S., Kossman A., Contreras P.A., Arias C., Basualdo J.A. 2010. A wide diversity of zoonotic intestinal parasites infects urban and rural dogs in Neuquén, Patagonia, Argentina. Veterinary Parasitology 167(1): 81–85. DOI: 10.1016/j.vetpar.2009.09.048
Stojčević D., Sušić V., Lučinger S. 2010. Contamination of soil and sand with parasite elements as a risk factor for human health in public parks and playgrounds in Pula, Croatia. Veterinarski Arhiv 80(6): 733–742.
Taylor L.H., Latham S.M., Woolhouse M.E. 2001. Risk factors for human disease emergence. Philosophical Transactions of the Royal Society B: Biological Sciences 356(1411): 983–989. DOI: 10.1098/rstb.2001.0888
Taylor M.A., Coop R.L., Wall R.L. 2016. Veterinary Parasitology. UK: John Wiley & Sons. 1032 p.
Traversa D., Di Cesare A., Lia R.P., Castagna G., Meloni S., Heine J., Strube K., Milillo P., Otranto D., Meckes O., Schaper R. 2011. New insights into morphological and biological features of Capillaria aerophila (Trichocephalida, Trichuridae). Parasitology Research 109(Suppl.1): 97–104. DOI: 10.1007/s00436-011-2406-4
Tudor P. 2015. Soil contamination with canine intestinal parasites eggs in the parks and shelter dogs from Bucharest area. Agriculture and Agricultural Science Procedia 6: 387–391. DOI: 10.1016/j.aaspro.2015.08.103
Ugbomoiko U., Ariza L., Heukelbach J. 2008. Parasites of importance for human health in Nigerian dogs: high prevalence and limited knowledge of pet owners. BMC Veterinary Research 4: 49. DOI: 10.1186/1746-6148-4-49
WHO. 2017. One Health. In: World Health Organization. Available from
WHO. 2020. Soil-transmitted helminth infection. In: World Health Organization. Available from
Young J.K., Olson K.A., Reading R.P., Amgalanbaatar S., Berger J. 2011. Is wildlife going to the dogs? Impacts of feral and free-roaming dogs on wildlife populations. BioScience 61(2): 125–132. DOI: 10.1525/bio.2011.61.2.7
Zajac A.M., Conboy G.A. 2012. Veterinary Clinical Parasitology. UK: Wiley-Blackwell. 354 p.