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Gastrointestinal parasites of canids, a latent risk to human health in Tunisia



Although data on the parasite environmental contamination are crucial to implement strategies for control and treatment, information about zoonotic helminths is very limited in Tunisia. Contamination of areas with canid faeces harboring infective parasite elements represents a relevant health-risk impact for humans. The aim of this study was to assess the environmental contamination with eggs and oocysts of gastrointestinal parasites of dogs and wild canids in Tunisia with special attention to those that can be transmitted to humans.


One thousand two hundred and seventy faecal samples from stray dogs and 104 from wild canids (red foxes and golden jackals) were collected from different geographical regions throughout Tunisia. The helminth eggs and protozoan oocysts were concentrated by sucrose flotation and identified by microscopic examination. The most frequently observed parasites in dog samples were Toxocara spp. (27.2%), E. granulosus (25.8%), and Coccidia (13.1%). For wild canid faeces, the most commonly encountered parasites were Toxocara spp. (16.3%) followed by Capillaria spp. (9.6%). The parasite contamination of dog faeces varied significantly from one region to another in function of the climate.


To our knowledge, the study highlights for the first time in Tunisia a serious environmental contamination by numerous parasitic stages infective to humans. Efforts should be made to increase the awareness of the contamination risk of such parasites in the environment and implement a targeted educational program.


Parasitic infections are among the most common infections worldwide, principally in developing countries with poor environmental sanitation and inadequate personal hygiene. In particular, soil-transmitted helminths (Ascaris lumbricoides, whipworm (Trichuris trichiura) and hookworm) causing the “neglected infections of poverty” have a relevant health-risk impact on humans and animals [1,2,3,4,5]. Nevertheless, gastrointestinal parasites of canids constitute another source of human and livestock infection mainly due to environmental contamination with faeces containing infective parasitic forms (eggs, larvae or oocysts) [6,7,8]. Several serious parasitic diseases transmitted by dogs, such as hydatidosis and toxocariasis, are regarded as serious public health problems especially in Mediterranean countries [9,10,11]. Wild canids are also the reservoir of a wide range of parasites including parasites that are shared between pets and humans [12,13,14]. Human infections are acquired via the ingestion of eggs or oocysts via contaminated foodstuffs or water, hands, inhalation of dust, and/or by penetration of larvae through the skin [15]. Geophagia (eating of earth) and shoeless walking are the most common risk factors of contamination in children [16, 17].

In Tunisia, the canine population is estimated at 800,000 dogs and is essentially composed of stray and semi-stray (free-roaming dogs which are fed by an owner) dogs that rarely receive deworming treatment [18]. The uncontrolled displacement of canids in rural and urban areas increases the contamination risk of the soil, food and water with parasitic elements. The dog faeces are not removed from the ground and may be a serious hazard for human health. Epidemiological studies have been performed on gastrointestinal helminths in necropsied dogs [19,20,21] and wild canids [21, 22] in Tunisia but relatively little information on the environmental contamination by protozoan oocysts or helminth eggs is currently available [23]. Thus, understanding the epidemiology of zoonotic parasitic infections due to canids is necessary to minimize the exposure risk to humans.

The aim of the present work was (i) to assess the data from an epidemiological survey of environmental contamination with helminth eggs and protozoan cysts of dogs, with special attention to those that can be transmitted to humans; and (ii) to investigate the possible role of wild canids in the transmission of gastrointestinal parasites to humans.


Sample collection

One thousand two hundred and seventy faecal samples from dogs (Canis familiaris) were collected from the soil from four climate zones in Tunisia: sub-humid (Kef), semi-arid (Kasserine, Sousse and Monastir), arid (Djerba Island, Zarzis and Metlaoui), and desertic (Douz and Tataouine) (Fig. 1). Forty samples were randomly collected from a proportion of the faeces observed over a soil surface of 200–400 m2 according to the abundance of faeces in each location. One hundred and four faeces from wild canids were isolated: 88 faecal samples around red fox burrows (Vulpes vulpes) from Djerba Island and 16 faeces from the rest sites of golden jackals (Canis aureus) from Zarzis. The samples were collected with the help of hunters and experienced forestry technicians based essentially on the defecation sites, the shape and size of faeces, and the footprints left by wild canids. All faeces were taken from rural, semi-urban, and urban sites in the vicinity of livestock breeding (ovine and bovine). Houses and animal husbandries were observed around all the study areas.

Fig. 1

Faecal sampling collections from dogs and wild canids in different Tunisian locations according to the climate: humid (blue), sub-humid (turquoise), semi-arid (green), Arid (brown), desertic (yellow)

Several sites were visited for each region (2–5) and samples were collected in spring and summer. The sampling was not related to a number of individual canids, but intended to represent the available parasite eggs or oocysts in the area. Faecal samples were collected without alcohol or formalin fixation and frozen at -80 °C for 7 days in order to partially inactivate infective stages of the parasites.

Microscopic and molecular analysis

The gastrointestinal helminth eggs and protozoan oocysts were concentrated by sucrose density gradient flotation with a specific gravity of 1.27 [24]. Slides were then systematically microscopically checked at 40× magnification. Using morphological and morphometric characteristics, each egg or protozoan oocyst was identified by light microscopic examination [25]. With the exception of Echinococcus granulosus and Dipylidium caninum, isolated parasites were identified at the family/genus level. Since the taeniid eggs are morphologically indistinguishable, Eg1121/1122 PCR was used to identify the E. granulosus among taeniid egg-positive samples. Briefly, an alkaline lysis using DTT (dithiothreitol) and KOH (potassium hydroxide) followed by an enzymatic digestion by proteinase K (Invitrogene, Karlsruhe, Germany) were performed to destroy the embryophore’s rigid shell. The total DNA was extracted using a phenol chloroform protocol [26]. The PCR approach was realized as previously described by Chaabane-Banaoues et al. [23].

The percentage of faecal samples found positive for at least one parasitic element (egg or oocyst) provided the parasite contamination index which was estimated as the number of positive parasite isolates/total number of examined samples in each location.

Statistical analysis

The categorical variables were expressed as percentages and the exact binomial confidence intervals were calculated (95% CI). The Pearson’s Chi-square and the Spearman’s correlation tests were used to compare the contamination indices according to the host (wild or domestic canid), the sampling regions, and the relationship between parasites (SPSS software, version 18.0). All P-values less than 0.05 were considered as statistically significant.

The dog faeces contamination indices higher than 4%, the temperature (annual average maximum temperature), and the rainfall (average yearly rainfall) of studied regions were compared using the principal component analysis (PCA) with MVSP software (Multivariate statistical package. MVSP. User’ manual. Version 3.1. KCS, 288. Pentraeth, Wales, UK. 2002).


The present study revealed the presence of numerous pathogenic helminth eggs and protozoan oocysts (Table 1 and Fig. 2). The overall contamination index was 55% (95% CI: 52.2–57.7) and 46.1% (95% CI: 36.5–55.6) for dog and wild canid faecal samples respectively. Multiple infections were less frequent (30.1%, 95% CI: 26.8–33.3) than single infection (70%, 95% CI: 66.7–73.2) in dog faeces (from all regions). Similar results were obtained for the wild canid (Djerba-Zarzis) samples, and 38.5% (95% CI: 29.1–47.8) of them presented multiple infections versus 61.5% (95% CI: 52.2–70.9) for single infections (data not shown).

Table 1 Parasite contamination index of dog faeces in relation to regions and climate
Fig. 2

Cestode and nematode eggs and oocysts observed in the canid faecal samples. a D. caninum egg-capsule. b Trichuris spp. c Capillaria spp. d Spirocerca spp. e Ancylostoma spp. f Toxocara spp. g Taeniidae. h Coccidian oocysts

Parasite distribution was significantly different between the dogs and wild canids in Zarzis and Djerba for E. granulosus (χ 2 = 28.95, df = 1, P < 0.0001), Toxocara spp. (χ 2 = 11.63, df = 1, P = 0.0006), Capillaria spp. (χ 2 = 21.25, df = 1, P < 0.0001) and Spirocerca spp.(χ 2 = 4.95, df = 1, P = 0.026) (Table 2). For the dog faeces, the most frequently observed parasites were Toxocara spp. (27.2%), E. granulosus (25.8%) and Coccidia (13.1%) (Table 1). Thanks to biomolecular analysis, 94% of Taeniidae samples (328 faeces) were identified as E. granulosus eggs (Table 1). Nevertheless, it should be noted that co-infection with other species of Taeniidae cannot be excluded. The wild canids were predominately infected with Toxocara spp. (16.3%) and Capillaria spp. (9.6%) (Table 2). No E. granulosus egg was detected in wild canids in Djerba and Zarzis regions whereas dog faeces were largely contamined (22.6%) (Table 2).

Table 2 Intestinal parasites in canids based on eggs and oocysts recovered in the faeces from Djerba-Zarzis regions

The parasite environmental contamination varied significantly from one region to another (Table 1). Echinococcus granulosus was predominant for the faecal samples from the arid region whereas Trichuris spp. was the most frequently observed parasite for the sub-humid area (Table 1). The other regions had a similar parasite distribution and Toxocara spp. was the most commonly parasite found. Dipylidium caninum, Spirocerca spp. and Capillaria spp. were present in dog faeces with an occurrence lower than 1% (Table 1).

As for the dog samples, the Spearman’s correlation coefficient demonstrated a positive correlation between E. granulosus and Toxocara spp. eggs (r s  = 0.55, P = 0.132), and a negative correlation between E. granulosus and Trichuris spp. eggs (r s  = -0.67, P = 0.044). The PCA graphics highlighted that Trichuris spp., Ancylostoma spp., and Coccidia distributions were significantly and positively correlated with rainfall (Fig. 3, Axis 2). The E. granulosus and Toxocara spp. isolates were ubiquitous even in high temperature regions (Fig. 3, Axis 1).

Fig. 3

Parasite contamination indices and Tunisian region bioclimatic characteristics described by principal component analysis. Temperature (C°): annual average maximum temperature; Rainfall (mm): annual average rainfall


Although data on the regional prevalence of parasites are crucial to implement strategies for control and treatment, information about parasite environmental contamination is very limited in Tunisia. Except for cystic echinococcosis, epidemiological studies of zoonotic helminths are rare and only few human case reports have been published. Significant levels of parasitism were observed more in dogs (55%) than in wild canids (46.1%). These contamination levels are comparable to those described for dog faecal samples in other countries such as Cuba (44.3%) [27], Canada (33.9%) [28] and Portugal (59.8%) [29]. To our knowledge, we cannot exclude that the faeces contamination indices were overestimated due to the coprophagic behaviour of canids (consummation of their own faeces, faeces of other canids and/or faeces of other species) [30]. The zoonotic agents Toxocara spp., E. granulosus, Ancylostoma spp. and Trichuris spp. were the most frequent parasites observed in the study. The situation presented here is grossly the same as that in several parts of the world such as Argentina [31], North America [32] or Iran [33]. Helminths encountered in the present study have at least one form infective to humans: the eggs for orally-ingested parasite species, and the free-living stages for skin-penetrating species. The faecal-oral route is the most common way of helminth and protozoan contamination. Thus, the consumption of uncooked vegetables irrigated by water polluted by animal faeces and/or soil ingestion could have a direct impact on human health and cause severe zoonoses [34, 35].

Contrary to previous studies that reported a high D. caninum prevalence in necropsied Tunisian dogs (43.6%) and wild canids (29%) [21, 22], only one dog positive sample was observed in our study. The results could be explained by an underestimation of copro-helminth prevalence compared to necropsy examination, especially for cestodes, where eggs are mainly intermittently released [28]. Similar results were observed in Nigeria where necropsy of dogs reported a contamination rate of 75% for D. caninum [36], whereas the direct analysis of faeces revealed a prevalence ranging from 5.7 to 12.3% [37].

Toxocara spp. are the most common parasites living in the intestines of dogs and wild canids worldwide [38]. Humans are accidental hosts who may become infected by ingesting embryonated eggs through contaminated vegetables/water or by direct contact with dogs [10, 39]. Human infection may cause severe damage usually involving the back of the eye, the liver, and the lungs [40]. In Tunisia, information about human toxocariasis seroprevalence is nowadays absent because only case reports have been described in the literature [41,42,43,44,45,46]. In the present study, an important environmental contamination with Toxocara spp. eggs has been demonstrated for dog (all regions) and wild canid (Djerba and Zarzis) faeces, 27.2 and 16.3% respectively. When infected with T. canis, one dog could expel thousands of eggs each day. These eggs are extremely resistant in the environment and could remain infective for 5 years under favorable conditions [47]. Thus, since the environment is seriously contaminated, this zoonosis could result in an important human health problem.

Despite efforts to control the disease, cystic echinococcosis remains a serious public health problem in Tunisia [48, 49]. The life-cycle of E. granulosus uses domestic dogs or wild canids as the final host and ungulates as intermediate host. Humans are accidental intermediate hosts and parasite infection from dog to humans may occur, directly by contact with pets or indirectly through contaminated food or soil. In the present study, the occurrence of E. granulosus eggs varied according to the area but no region free of eggs was found. Despite the description of E. granulosus tapeworm in red foxes [21] and golden jackals [22] from north-western and central regions of Tunisia, no E. granulosus egg was detected in our wild canid samples although dog faeces contamination was not negligible in the same area (22.6%). The absence of E. granulosus in wild canids might be explained by their lack of opportunity to consume contaminated carcasses of intermediate hosts. However, in the presence of the suitable intermediate hosts in the diets of these animals, E. granulosus was detected in wolves but not in red foxes in Portugal [13, 50]. Red foxes are rarely infected with E. granulosus, usually with low parasite burdens, and are generally considered of limited importance for cystic echinococcosis transmission [47]. Therefore, it can be assumed that in Tunisia, wild canids are not implied in the disease transmission and that dogs remain the main definitive host in the life-cycle of E. granulosus.

The significant and positive correlation between E. granulosus and Toxocara spp. eggs observed in the present study, even in arid and desertic environment, is due to their thick outer shell (protein coat) which confers them a resistance to desiccation and to high temperature (30–80 °C) [51,52,53].

Trichuris spp. is found in domestic and wild canids worldwide. Although it is generally considered as non-zoonotic [54], some human cases of visceral larva migrans due to canid Trichuris species have been described [55,56,57]. Human infection is due to the accidental ingestion of embryonated eggs. Trichuris spp. was more geographically restricted than the other parasites found in this study and the prevalence of this parasite varied considerably (0–52.8%) from one region to another in function of the climate. Thus, in the sub-humid area (Kef), the environment is seriously contaminated (52.8%) whereas in the semi-arid neighbouring region (Kasserine) the contamination index was very low (0.7%). In the desertic and arid regions (Tataouine, Douz and Metlaoui) this parasite was totally absent. A previous study conducted in the Tunisian sub-humid region, reported similar result with a prevalence of 33% for T. vulpis in wild canids [22]. Precipitation and soil humidity are required for maintaining the parasite viability and Trichuris spp. eggs are less likely to survive in drier and sunnier locations and are unlikely to embryonate [52].

Capillaria spp. has a direct life-cycle that requires only one host. Adult worms invade the lungs of domestic and wild canids but may also be found in other mammals including humans [47]. Capillaria spp. was the second parasite most frequently encountered in the wild canid faeces (9.6%) and had a limited presence in dog faeces (0.1%). Similar results were described in Europe with an occurrence of 0–0.7% and 60.3–93.8% for dogs and foxes, respectively [58,59,60]. Thus, Capillaria spp. seems to be restricted to wildlife due to host-parasite interactions and dietary habits. In Tunisia, it can be assumed that wild canids act as a reservoir for capillariasis and could be responsible for the transmission of Capillaria populations to dogs.


To our knowledge, the results of this study highlight, for the first time in Tunisia, the environmental contamination by numerous gastrointestinal parasites. In Tunisia, people’s awareness regarding zoonotic diseases transmitted by dogs is insufficient. The transmission of gastrointestinal helminths is enhanced by a high stray or semi-stray dog population, inadequate deworming treatment, the close contact of untreated dogs with humans and the favourable climatic conditions for the survival of infective stages outside the hosts. Thus, efforts should be made to increase the awareness of the presence of parasites in the environment and to implement a targeted educational program especially for the dog owners.



Confidence interval


Principal components analysis


  1. 1.

    Taye B, Alemayehu B, Birhanu A, Desta K, Addisu S, Petros B, et al. Podoconiosis and soil-transmitted helminths (STHs): double burden of neglected tropical diseases in Wolaita zone, rural Southern Ethiopia. PLoS Negl Trop Dis. 2013;7(3):e2128.

    Article  PubMed  PubMed Central  Google Scholar 

  2. 2.

    Harrington H, Bradbury R, Taeka J, Asugeni J, Asugeni V, Igeni T, et al. Prevalence of soil-transmitted helminths in remote villages in East Kwaio, Solomon Islands. Western Pac Surveill Response J. 2015;6(3):51–8.

    Article  PubMed  PubMed Central  Google Scholar 

  3. 3.

    Ng’etich AI, Rawago FO, Jura WG, Mwinzi PN, Won KY, Odiere MR. A cross-sectional study on schistosomiasis and soil-transmitted helminths in Mbita district, western Kenya using different copromicroscopic techniques. Parasit Vectors. 2016;9:87.

    Article  PubMed  PubMed Central  Google Scholar 

  4. 4.

    Ayeh-Kumi PF, Addo-Osafo K, Attah SK, Tetteh-Quarcoo PB, Obeng-Nkrumah N, Awuah-Mensah G, et al. Malaria, helminths and malnutrition: a cross-sectional survey of school children in the South-Tongu district of Ghana. BMC Res Notes. 2016;9:242.

    Article  PubMed  PubMed Central  Google Scholar 

  5. 5.

    Kunwar R, Acharya L, Karki S. Trends in prevalence of soil-transmitted helminth and major intestinal protozoan infections among school-aged children in Nepal. Trop Med Int Health. 2016;21(6):703–19.

    Article  PubMed  Google Scholar 

  6. 6.

    Macpherson CN. Human behaviour and the epidemiology of parasitic zoonoses. Int J Parasitol. 2005;35(11–12):1319–31.

    Article  PubMed  Google Scholar 

  7. 7.

    Papazahariadou M, Founta A, Papadopoulos E, Chliounakis S, Antoniadou-Sotiriadou K, Theodorides Y. Gastrointestinal parasites of shepherd and hunting dogs in the Serres Prefecture, northern Greece. Vet Parasitol. 2007;148(2):170–3.

    CAS  Article  PubMed  Google Scholar 

  8. 8.

    Bentounsi B, Meradi S, Ayachi A, Cabaret J. Cestodes of untreated large stray dog populations in Algeria: A reservoir for herbivore and human parasitic diseases. Open Vet Sci J. 2009;3:64–7.

    Article  Google Scholar 

  9. 9.

    Dakkak A. Echinococcosis/hydatidosis: a severe threat in Mediterranean countries. Vet Parasitol. 2010;174(1–2):2–11.

    CAS  Article  PubMed  Google Scholar 

  10. 10.

    Overgaauw PA, van Knapen F. Veterinary and public health aspects of Toxocara spp. Vet Parasitol. 2013;193(4):398–403.

    Article  PubMed  Google Scholar 

  11. 11.

    Alvarez Rojas CA, Romig T, Lightowlers MW. Echinococcus granulosus sensu lato genotypes infecting humans- review of current knowledge. Int J Parasitol. 2014;44(1):9–18.

    Article  PubMed  Google Scholar 

  12. 12.

    Elmore SA, Lalonde LF, Samelius G, Alisauskas RT, Gajadhar AA, Jenkins EJ. Endoparasites in the feces of arctic foxes in a terrestrial ecosystem in Canada. Int J Parasitol Parasites Wildl. 2013;2:90–6.

    Article  PubMed  PubMed Central  Google Scholar 

  13. 13.

    Guerra D, Armua-Fernandez MT, Silva M, Bravo I, Santos N, Deplazes P, et al. Taeniid species of the Iberian wolf (Canis lupus signatus) in Portugal with special focus on Echinococcus spp. Int J Parasitol Parasites Wildl. 2013;2:50–3.

    Article  PubMed  Google Scholar 

  14. 14.

    Duscher GG, Leschnik M, Fuehrer HP, Joachim A. Wildlife reservoirs for vector-borne canine, feline and zoonotic infections in Austria. Int J Parasitol Parasites Wildl. 2015;4(1):88–96.

    Article  PubMed  Google Scholar 

  15. 15.

    Lee AC, Montgomery SP, Theis JH, Blagburn BL, Eberhard ML. Public health issues concerning the widespread distribution of canine heartworm disease. Trends Parasitol. 2010;26(4):168–73.

    Article  PubMed  Google Scholar 

  16. 16.

    Alelign T, Degarege A, Erko B. Soil-transmitted helminth infections and associated risk factors among schoolchildren in Durbete Town, northwestern Ethiopia. J Parasitol Res. 2015. doi:10.1155/2015/641602.

    PubMed  PubMed Central  Google Scholar 

  17. 17.

    Doni NY, Gürses G, Şimşek Z, Zeyrek FY. Prevalence and associated risk factors of intestinal parasites among children of farm workers in the southeastern Anatolian region of Turkey. Ann Agric Environ Med. 2015;22(3):438–42.

    Article  Google Scholar 

  18. 18.

    Aoun K, Bouratbine A. Epidemiological data concerning hydatidosis in Tunisia. Med Mal Infect. 2007;37:S40–2.

    Article  Google Scholar 

  19. 19.

    Lahmar S, Kilani M, Torgerson PR. Frequency distributions of Echinococcus granulosus and other helminths in stray dogs in Tunisia. Ann Trop Med Parasitol. 2001;95(1):69–76.

    CAS  Article  PubMed  Google Scholar 

  20. 20.

    Lahmar S, Sarciron ME, Rouiss M, Hammouda A, Youssfi M, Mensi M. Echinococcus granulosus and other intestinal helminths in semi-stray dogs in Tunisia: infection and re-infection rates. Tunis Med. 2008;86(3):279–86.

    Google Scholar 

  21. 21.

    Lahmar S, Boufana BS, Lahmar S, Inoubli S, Guadraoui M, Dhibi M, et al. Echinococcus in the wild carnivores and stray dogs of northern Tunisia: the results of a pilot survey. Ann Trop Med Parasitol. 2009;103(4):323–31.

    CAS  Article  PubMed  Google Scholar 

  22. 22.

    Lahmar S, Boufana B, Ben Boubaker S, Landolsi F. Intestinal helminths of golden jackals and red foxes from Tunisia. Vet Parasitol. 2014;204(3–4):297–303.

    Article  PubMed  Google Scholar 

  23. 23.

    Chaabane-Banaoues R, Oudni-M’rad M, Cabaret J, M’rad S, Mezhoud H, Babba H. Infection of dogs with Echinococcus granulosus: causes and consequences in an hyperendemic area. Parasit Vectors. 2015;8:231.

    Article  PubMed  PubMed Central  Google Scholar 

  24. 24.

    Dryden MW, Payne PA, Ridley R, Smith V. Comparison of common fecal flotation techniques for the recovery of parasite eggs and oocysts. Vet Ther. 2005;6(1):15–28.

    CAS  PubMed  Google Scholar 

  25. 25.

    Mehlhorn H. Encyclopedia of Parasitology. 3rd ed. Berlin: Springer; 2008.

    Book  Google Scholar 

  26. 26.

    Sambrook J, Fitsch EF, Maniatis T. Molecular Cloning: A Laboratory Manual. 2nd ed. New York: Cold Spring Harbor, Laboratory Press; 1989.

    Google Scholar 

  27. 27.

    Puebla LEJ, Nunez FA, Rivero LR, Hernandez YR, Garcia IS, Millan IA. Prevalence of intestinal parasites in dogs from municipality La Lisa, Havana, Cuba. J Vet Sci Technol. 2015;6:5.

    Google Scholar 

  28. 28.

    Villeneuve A, Polley L, Jenkins E, Schurer J, Gilleard J, Kutz S, et al. Parasite prevalence in fecal samples from shelter dogs and cats across the Canadian provinces. Parasit Vectors. 2015;8:281.

    Article  PubMed  PubMed Central  Google Scholar 

  29. 29.

    Mateus TL, Castro A, Ribeiro JN, Vieira-Pinto M. Multiple zoonotic parasites identified in dog feces collected in Ponte de Lima, Portugal - a potential threat to human health. Int J Environ Res Public Health. 2014;11(9):9050–67.

    Article  PubMed  Google Scholar 

  30. 30.

    Nijsse R, Mughini-Gras L, Wagenaar JA, Ploeger HW. Coprophagy in dogs interferes in the diagnosis of parasitic infections by faecal examination. Vet Parasitol. 2014;204(3–4):304–9.

    CAS  Article  PubMed  Google Scholar 

  31. 31.

    Soriano SV, Pierangeli NB, Roccia I, Bergagna HF, Lazzarini LE, Celescinco A, et al. A wide diversity of zoonotic intestinal parasites infects urban and rural dogs in Neuquen, Patagonia, Argentina. Vet Parasitol. 2010;167(1):81–5.

    Article  PubMed  Google Scholar 

  32. 32.

    Bridger KE, Whitney H. Gastrointestinal parasites in dogs from the Island of St. Pierre off the south coast of Newfoundland. Vet Parasitol. 2009;162(1–2):167–70.

    Article  PubMed  Google Scholar 

  33. 33.

    Beiromvand M, Akhlaghi L, Fattahi Massom SH, Meamar AR, Motevalian A, Oormazdi H, et al. Prevalence of zoonotic intestinal parasites in domestic and stray dogs in a rural area of Iran. Prev Vet Med. 2013;109(1–2):162–7.

    Article  PubMed  Google Scholar 

  34. 34.

    Thompson RC, Smith A. Zoonotic enteric protozoa. Vet Parasitol. 2011;182(1):70–8.

    CAS  Article  PubMed  Google Scholar 

  35. 35.

    Adanir R, Tasci F. Prevalence of helminth eggs in raw vegetables consumed in Burdur, Turkey. Food Control. 2013;31(2):482–4.

    Article  Google Scholar 

  36. 36.

    Umar YA. Intestinal helminthoses in dogs in Kaduna Metropolis, Kaduna State, Nigeria. Iran J Parasitol. 2009;4(1):34–9.

    CAS  Google Scholar 

  37. 37.

    Ugbomoiko US, Ariza L, Heukelbach J. Parasites of importance for human health in Nigerian dogs: high prevalence and limited knowledge of pet owners. BMC Vet Res. 2008;4:49.

    Article  PubMed  PubMed Central  Google Scholar 

  38. 38.

    Macpherson CNL. The epidemiology and public health importance of toxocariasis: A zoonosis of global importance. Int J Parasitol. 2013;43(12–13):999–1008.

    Article  PubMed  Google Scholar 

  39. 39.

    El-Tras WF, Holt HR, Tayel AA. Risk of Toxocara canis eggs in stray and domestic dog hair in Egypt. Vet Parasitol. 2011;178(3–4):319–23.

    Article  PubMed  Google Scholar 

  40. 40.

    Fan CK, Liao CW, Cheng YC. Factors affecting disease manifestation of toxocarosis in humans: genetics and environment. Vet Parasitol. 2013;193(4):342–52.

    CAS  Article  PubMed  Google Scholar 

  41. 41.

    Arfaoui B, Boussetta N, Abid R, Sayhi S, Batikh R, Ben Abdelhafidh N, et al. Toxocarose viscérale chez l’adulte, à propos de 2 cas. Rev Med Interne. 2015;36 Suppl 2:A116–7.

    Article  Google Scholar 

  42. 42.

    Hamrouni S, Boussetta N, Dhahri R, Sayhi S, Gharsallah I, Metoui L, Suppl 2. Toxocarose oculaire: à propos de trois cas. Rev Med Interne. 2015;36:A116.

    Article  Google Scholar 

  43. 43.

    Lajmi M, Boussetta N, Sayhi S, Dhahri R, Abid R, Batikh R, Suppl 2. Une parasitose rare: la toxocarose (à propos de 5 cas). Rev Med Interne. 2015;36:A118.

    Article  Google Scholar 

  44. 44.

    Mrissa M, Battikh R, Ben Abdelhafidh N, Jemli B, Azzouz O, Zaouali J, et al. Toxocara canis encephalitis: case report. Rev Med Interne. 2005;26(10):829–32.

    CAS  Article  PubMed  Google Scholar 

  45. 45.

    Taheri O, Blaison G, Sawaf K, Potelon P, De Briel D, Martinot M, Suppl 2. Toxocarose révélée par des nodules pulmonaires excavés et une hyperéosinophilie chez une patiente présentant des douleurs mammaires atypiques. Rev Med Interne. 2015;36:A117.

    Article  Google Scholar 

  46. 46.

    Trabelsi H, Neji S, Cheikhrouhou F, Sellami H, Guidara R, Mhiri W, et al. Ocular toxocariasis: a case report. J Fr Ophtalmol. 2014;37(6):e81–2.

    CAS  Article  PubMed  Google Scholar 

  47. 47.

    Otranto D, Cantacessi C, Dantas-Torres F, Brianti E, Pfeffer M, Genchi C, et al. The role of wild canids and felids in spreading parasites to dogs and cats in Europe. Part II: Helminths and arthropods. Vet Parasitol. 2015;213(1–2):24–37.

    Article  PubMed  Google Scholar 

  48. 48.

    Chahed MK, Bellali H, Touini H, Cherif R, Ben Safta Z, Essoussi M, et al. L’incidence chirurgicale du kyste hydatique en Tunisie : résultats de l’enquête 2001–2005 et tendance évolutive entre 1977–2005. Arch Inst Pasteur Tunis. 2010;87(1–2):43–52.

    CAS  PubMed  Google Scholar 

  49. 49.

    Oudni-M’rad M, M’rad S, Babba H. Molecular and epidemiology data on cystic echinococcosis in Tunisia. In: Rodriguez-Morales AJ, editor. Current topics in echinococcosis. Rijeka: InTech; 2015. p. 56–74.

    Google Scholar 

  50. 50.

    Eira C, Vingada J, Torres J, Miquel J. The helminth community of the red fox, Vulpes vulpes, in Dunas de Mira (Portugal) and its effect on host condition. Wildl Biol Pract. 2006;2(1):26–36.

    Article  Google Scholar 

  51. 51.

    Thevenet PS, Jensen O, Drut R, Cerrone GE, Grenovero MS, Alvarez HM, et al. Viability and infectiousness of eggs of Echinococcus granulosus aged under natural conditions of inferior arid climate. Vet Parasitol. 2005;133(1):71–7.

    Article  PubMed  Google Scholar 

  52. 52.

    Maya C, Torner-Morales FJ, Lucario ES, Hernández E, Jiménez B. Viability of six species of larval and non-larval helminth eggs for different conditions of temperature, pH and dryness. Water Res. 2012;46(15):4770–82.

    CAS  Article  PubMed  Google Scholar 

  53. 53.

    Tarbiat B, Jansson DS, Hoglund J. Environmental tolerance of free-living stages of the poultry roundworm Ascaridia galli. Vet Parasitol. 2015;209(1–2):101–7.

    Article  PubMed  Google Scholar 

  54. 54.

    Traversa D. Are we paying too much attention to cardio-pulmonary nematodes and neglecting old-fashioned worms like Trichuris vulpis? Parasit Vectors. 2011;4:32.

    Article  PubMed  PubMed Central  Google Scholar 

  55. 55.

    Areekul P, Putaporntip C, Pattanawong U, Sitthicharoenchai P, Jongwutiwes S. Trichuris vulpis and T. trichiura infections among schoolchildren of a rural community in northwestern Thailand: the possible role of dogs in disease transmission. Asian Biomed. 2010;4(1):49–60.

    CAS  Google Scholar 

  56. 56.

    Dunn JJ, Columbus ST, Aldeen WE, Davis M, Carroll KC. Trichuris vulpis recovered from a patient with chronic diarrhea and five dogs. J Clin Microbiol. 2002;40(7):2703–4.

    Article  PubMed  PubMed Central  Google Scholar 

  57. 57.

    Marquez-Navarro A, Garcia-Bracamontes G, Alvarez-Fernandez BE, Avila-Caballero LP, Santos-Aranda I, Diaz-Chiguer DL, et al. Trichuris vulpis (Froelich, 1789) infection in a child: a case report. Korean J Parasitol. 2012;50(1):69–71.

    Article  PubMed  PubMed Central  Google Scholar 

  58. 58.

    Hauser M, Basso W, Deplazes P. Dog and fox faecal contamination of farmland. Schweiz Arch Tierheilkd. 2015;157(8):449–55.

    CAS  Article  PubMed  Google Scholar 

  59. 59.

    Al-Sabi MN, Kapel CM, Johansson A, Espersen MC, Koch J, Willesen JL. A coprological investigation of gastrointestinal and cardiopulmonary parasites in hunting dogs in Denmark. Vet Parasitol. 2013;196(3–4):366–72.

    Article  PubMed  Google Scholar 

  60. 60.

    Al-Sabi MN, Halasa T, Kapel CM. Infections with cardiopulmonary and intestinal helminths and sarcoptic mange in red foxes from two different localities in Denmark. Acta Parasitol. 2014;59(1):98–107.

    Article  PubMed  Google Scholar 

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The authors are grateful to Pr. Jacques Cabaret (UMR 1282, ISP INRA and F. Rabelais University, Nouzilly, France) and to Pr. Franck Boué (Anses, National Reference Laboratory for Echinococcus spp., Nancy, France) for critically reading the manuscript. The authors also wish to thank Nedra Kerkeni (Higher Institute of Biotechnology of Monastir, Tunisia) for her assistance with the linguistic part of this paper. The authors thank Mohamed Mourad Chaabane for his technical help for the Fig. 1 design.


This study was funded by the Tunisian Ministry of Higher Education and Scientific Research. The funding source is not involved in the study design, in the collection, analysis and interpretation of data, in the writing of the report, and in the decision to submit the article for publication.

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The data supporting the conclusions of this article are included within the article. Raw data are available from the corresponding authors on reasonable request.

Authors’ contributions

MOM: participated in the design of the study, contributed to the acquisition of data collection, and have been involved in drafting the manuscript. RCB: contributed to the data collection, carried out the molecular genetic studies and have been involved in drafting the manuscript. SM: participated in the coordination of the study, data collection and revised critically the manuscript for important intellectual content. FT: was involved in the statistical analysis and has critically revised the manuscript. HM: participated in carying out the molecular genetic studies. HB: participated in the design of the study and was involved in critically revising the manuscript. All authors read and approved the final manuscript.

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Correspondence to Myriam Oudni-M’rad.

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Oudni-M’rad, M., Chaâbane-Banaoues, R., M’rad, S. et al. Gastrointestinal parasites of canids, a latent risk to human health in Tunisia. Parasites Vectors 10, 280 (2017).

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  • Gastrointestinal parasites
  • Environmental parasite contamination
  • Zoonosis
  • Tunisia
  • Canids