Occurrence of Helminthic Infections in Dogs of the City of Marília/SP/Brazil and Its Repercussion on Public Health
P.H.F. Sousa; R.M. Antonine; J.K.P. Nunes; K.D.S. Bresciani; F.F.R. Manhoso
Gastrointestinal helminths in dogs have been commonly diagnosed, despite the existence of therapeutic and prevention measures; moreover, there's a growing number of these animals, hence increasing the human exposure risk to parasitic agents, once that many of these have a zoonotic character. Visceral Larva Migrans stand out, due to infection by Toxocara spp. larva and Cutaneous Larva Migrans caused by Ancylostoma caninum and brasiliense infecting larva (Gennari et al. 1999, Veronesi 2007). Trichuris vulpis' Visceral Larva Migrans, another dog's parasite, is also reported in human beings (Sakano et al. 1980). Public parks' soil constitutes an important contamination source, due to the elimination of contaminated feces that can predispose people to direct contact (Bresciani et al. 2005). Articles report this concern, as the one executed in the city of São Paulo/SP, where 45% of dog's fecal samples were positive, for single and combined infections, where Ancylostoma spp. was represented by 20.4% followed by Toxocara canis (8.49%), Giardia spp. (7.65%), Cryptosporidium parvum (2.83%), Cystoisospora spp. (2.55%), Sarcocystis spp. (1.7%), Hammondia heydorni (0.85%) and Spirocerca lupi, Trichuris vulpis, Dipylidium caninum (0.28%) (Gennari et al. 1999). On the shore of Praia Grande/SP, it was verified that 45.9% of the collected samples were contaminated by Ancylostoma spp. and 1.2% by Toxocara spp. (Castro et al. 2005). In Ribeirão Preto/SP, 56.8% of the samples were positive, of which, there were single infections of Ancylostoma spp. (41.7%), Toxocara canis (24.2%), Trichuris vulpis (15.7%), Giardia spp. (10.2%) and Isospora spp. (3.3%). The multiple infections were observed, of Ancylostoma spp./Toxocara canis (27.4%), Ancylostoma spp./Trichuris vulpis (24.5%), Ancylostoma spp./Toxocara canis/Giardia spp. (14.7%) and Toxocara canis/Trichuris vulpis (12.7%) (Capuano & Rocha 2006). Focusing on the prevention aspect of the control of helminthiasis in dogs and its repercussion in public health, the importance of population awareness is highlighted, through sanitary education (Bresciani et al. 2005). Considering the zoonotic character of some canine helminths, the occurrence of these agents in dogs from the city of Marília/SP/Brazil was registered.
Materials and Methods
Intending to verify the occurrence of helminths in dogs, 50 fecal samples were collected, of different breeds, both genders, with ages ranging from two months to eight years old, from the city of Marília/SP/Brazil, cared for in the Veterinary Hospital of the University of Marília, from May to August 2008, divided into two equal groups, where A is characterized by treated animals with vermifuges and B with untreated animals using coproparasitology (Willis 1921), in accordance with the Ethic Committee in Human and Animal Research from the referred institution.
From the analysis of group A, no positive samples for any gastrointestinal helminths were found; on the other hand, on group B, 52% had positive results manifested in single and multiple infections. In single infections, Ancylostoma spp. represented 46.15%, Trichuris vulpis 15.40% and Toxocara canis 7.69%. The association of Toxocara canis/Ancylostoma spp. in combined infections had the largest occurrence (23.07%), followed by Toxocara canis/Trichuris vulpis (7.69%).
Discussion and Conclusions
Due to the concern with public health, helminths with zoonosis impact have an importance in the human/animal relation, where triage and diagnosis of parasites in evidence have the purpose of preserving animal health, limiting the parasitic infection to man, with posterior diminishing to the public expenses related to the parasitic illnesses. Thus, in the samples of the group composed by animals with anthelmintic history, no positive results were found for helminths, confirming the importance of prevention treatment (Veronesi 2007). The helminth with the largest occurrence in this study was Ancylostoma spp., and this result was also found in another experiment (Gennari et al. 1999). On the aspect of verifying environmental contamination, the genus Ancylostoma was also the most predominant, supporting our results (Nunes et al. 2000, Castro et al. 2005, Capuano & Rocha 2006). As for Trichuris vulpis, some authors verified low occurrence for the parasite (Gennari et al. 1999), though others presented similar indexes to the found in our studies (Capuano & Rocha 2006). Amongst combined infections, the most observed association was of Ancylostoma spp./Toxocara canis, followed by Toxocara canis/Trichuris vulpis confirming the result found in recent experiment (Capuano & Rocha 2006). The precarious environment conditions aids infections in dogs as well as eggs dispersal in the environment, representing an important source of environmental contamination, which can lead man to develop Cutaneous and Visceral Larva Migrans (Veronesi 2007). The prevention through anthelmintic is the most efficient method to guarantee animal health benefiting public health, fact proven by group A, consequently authorities can be alerted to implement sanitary programs aiming the control of homeless dogs and promoting education in population health in general. The estimate infection by gastrointestinal nematodes on the canine population is an important data for veterinarians, that can use this information to orient owners about educational measures, reducing this way, the risks of exposure to man. Considering the presented results, it's possible to infer that anthelmintic treatment is an effective and efficient process in the control and prevention of helminthiasis in dogs, seeing that the group represented by treated animals with anthelmintic did not register a single positive sample, while on the untreated group, the overall occurrence was of 52%, with Ancylostoma spp. the most predominant, followed by Trichuris vulpis and Toxocara canis, in isolated infections and Toxocara canis/Ancylostoma spp. and Toxocara canis/Trichuris vulpis when in association, respectively.
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