doi:10.5455/vetworld.2013.87-90

Aim: The objective of this study was to determine the possible extent of soil contamination at different public places with Toxocara species eggs. 
 
Materials and Methods: A Total of 327 samples of soil were collected and examined from different locations which are of public health importance like public parks, playgrounds, door mat dusts, Sidewalks or road sides, in Bareilly, Uttar Pradesh, to establish the prevalence of Toxocara eggs. Samples were also categorised in to sandy type (225) and clay type (102) which were examined by Dunsmore modified technique. 
 
Results: 42 samples out of 327 (12.84%) were found to be contaminated with the Toxocara spp.eggs and public parks were more contaminated than the other sites we studied. Clay type soil samples were found to be more contaminated than sandy type with a prevalence of 17.64%. 
 
Conclusions: The prevalence of this zoonotic parasite in soil has implications for the spread of human disease in these areas. The authors believe that this may constitute a significant health risk, particularly to children.


Introduction
environment, parks and playgrounds in particular, with the eggs of T. canis [4,5].Toxocariasis is a zoonotic disease caused by the Several reports of soil sampling from different larvae stage of Toxocara canis (T.canis) and Toxocara parts of the world, demonstrated widespread contamicati (T.cati), which are the common roundworms nation of the environment, parks and play grounds in living in the intestines of almost all new-born puppies, particular, with the eggs of Toxocara species [6,7,8].In kittens and in some adult dogs and cats [1].It is also India, several surveys revealed prevalence ranging found in a larval form in the tissues of all these animals from 2.21-40.4% [9,10,11].In addition, the assessment and in many birds and mammals, including humans.
of soil contamination requires reliable techniques for Infected Dogs and cats which harbour adult worms separating parasites from soil particles to facilitate pass the Toxocara eggs into the environment in their identification.Many techniques have been described, faeces.During a period of maturation, a larva develops and they vary in the materials used and the percentage within the egg and it is then infective if ingested.
of parasites recovered [12,13].Children are most commonly infected when they eat When studying the prevalence of soil contamisoil contaminated with eggs or put objects contamination by zoonotic parasites, some variables must be nated with eggs into their mouths [2].
taken into consideration.The soil texture is one of Human Toxocariasis occurs after ingestion of those important variables once that interactions infective eggs of Toxocara spp.and the subsequent between the soil structure and the flotation solutions migration of larvae, particularly to liver, lungs, muscles can interfere with parasite recovery.Nevertheless, the and brain.It accounts for considerable preventable relationship between soil texture and the presence of childhood illnesses and blindness and is often Toxocara spp.eggs is not direct.Samples with similar associated with poor hygiene.Although the clinical grain size composition can vary in the number of eggs features vary, three syndromes are recognised: Toxocaral present due to other factors such as intensity of visceral larva migrans, ocular larva migrans and covert contamination, action of earthworms, wind and rainfall Toxocariasis [3].Dog's ownership which is widening [12,13]. in urban agglomerations creates a continuing increasing During the course of sampling and laboratory trend.A growing danger of contamination of human analyses, many factors influence the results of soil environment with infectious stages of zoonoses originating examinations.These include sample site selection, the from dogs and cats is related to this phenomenon.Soil number and volume of samples, depth of sampling, sampling shows widespread contamination of the season of examination, method of egg recovery, These were situated nearby to schools and colleges.preservation of samples and laboratory skills [12].
Road side / sidewalk samples were taken from both the Since a primary source of exposure for children is sides of streets of the colonies where dogs are freely contaminated parks and playgrounds, this study was roaming.Forty four door mat samples were collected conducted to determine the level of contamination with from the hostels, Divisions, and veterinary hospital of Toxocara spp.eggs in these sites.Therefore the IVRI, Izatnagar.The soil samples were divided into objective of this study was to determine the prevalence sandy type and clay type. of Toxocara eggs in soil samples from places of public Parasitological examination: To recover parasitic health importance in and around Bareilly, Uttar Pradesh.
eggs, the soil samples were examined by Dunsmore The study area, Bareilly city is the district floatation fluid.The possibility of observation of eggs town of Bareilly, Uttar Pradesh.It is situated on the side of parasites increases when the amount of soil of the river Ramganga (a tributary of the river Ganges), increases [13].From the previous studies in which the 243 km West of Lucknow, the capital city of Uttar authors mentioned that the 30 g of soil is the maximum Pradesh, and 254 km East of Delhi.The climate is hot, quantity of soil that can be efficiently processed, we humid subtropical, however, the winters are bit cold, used 30 g of soil in our study.Soil samples were used with a temperature ranging from 4 to 15°C and the 2 after they had been sieved through 4mm meshes to annual rainfall is around 500-700 mm.The study area remove stone and large pieces of organic matter.In a has good veterinary facilities, a sizeable dog-owning beaker of 100 ml, 30 g of soil were soaked overnight population and a growing stray dog problem.During with 50 ml of distilled water and three drops of Tween-10 months period, from September 2010 to June 2011, 80.The mixture was homo-genized using an electric a total of 327 samples (approximately 100 gm each) mixer (Multimixer and Creamer, Tattil, India) for 10 were collected from each of the site like public parks, min and rested for 5 min.Two centrifuge tubes of 15 ml play grounds, doormat samples, sidewalks or road were filled with the mixture and centrifuged for 10 min sides in Bareilly.An eight-centimeter PVC pipe was at 2000 rpm.The supernatant was discarded and used to collect the soil samples because Toxocara spp.
NaNO was added to the half of the tube and the 3 eggs are more abundant in the top 0±8 cm than in sediment were suspended.The tubes were filled to the deeper layers [14].
top with NaNO and a slide placed in the menisci for 25 3 Design of study/sources of sample collection: Four min.Three slides were used for each tube and then types of samples were chosen for collection like 1) observed under microscope.No attempt was made to public parks 2) play grounds 3) road sides / sidewalks differentiate between eggs of T. canis and T. cati.Based and 4) door mat.Samples were also categorised in to on the morphology and morphometry the helminth ova sandy type and clay type.Parks were smaller type were identified as Toxocara spp.[15].which was located in the residential areas.These parks

Results
were fenced by iron rods but the access of dogs could not be prevented by the fence.Selected play grounds A total of 327 soil samples were examined and 42 were fenced properly where invasion of dogs was less.
(12.84%) were found to contain eggs of Toxocara   species (Table-1, Fig- 1).Out of 94 samples examined destruction of Toxocara spp eggs.Road sides and from public parks 16 were found positive for Toxocara sidewalks are the places where stray dogs are attracted species eggs, with a prevalence of 17.02%.The public by left out food materials, also serving as a common parks were found to be more contaminated than other defeacating places for dogs, are a potential source of sites that were examined.Next higher prevalence was Toxocara egg transmission.We found that doormat seen in door mat samples (13.33%), followed by dust samples are contaminated next to the public parks samples of road sides or sidewalks with a prevalence of samples as the doormat dust contains accumulated 11.71%.The least prevalence of 8.33% was found in soils of different sites and most of the doormats of the playgrounds.Clay type soil harboured a higher IVRI hostels were shown positive for Toxocara spp percentage of Toxocara eggs when compared with eggs, as dogs were seen frequently sitting on doormats, sandy soil, with 24 / 225 sandy soil samples being where they defecate on the mats.positive for Toxocara eggs at a prevalence rate of Over the past two decades, many reports have 10.66%.However, 18/102 clay type soil samples were documented contamination rates of Toxocara eggs in positive for Toxocara eggs, with the prevalence several countries [2,16,17].Although it is not possible percentage of 17.64 (Table-2, Fig- 2).
to compare present study directly with these surveys because of the different sampling and detection Discussion methods used, the contamination rates observed here We explored possible extent of soil contamination are relatively similar to those reported previously.Eggs for this zoonotic infection.The present study was of Ancylostoma, Capillaria, Trichuris and Toxascaris carried out to ascertain contamination rates at the sites leonina have been recovered from various public parks of public health importance in Bareilly.Our study [2,11].The occurrence of Toxocara eggs in public revealed 12.84% prevalence of Toxocara eggs in soil parks, especially in the vicinity of children play areas is samples collected from different locations of Bareilly a matter of concern for public health.The examination city.Out of 94 samples examined from public parks 16 of soil in our study revealed that the contamination of were found positive for Toxocara species eggs, with a public parks is higher (17.02%) than the contamination prevalence of 17.02%.The public parks were found to of soil at other sites.A similar situation was noticed in be more contaminated than other sites that were Iran and Italy where the public parks were more contaexamined.Next higher prevalence was seen in door minated with Toxocara eggs than the playgrounds mat samples (13.33%), followed by samples of road [2,16].sides or sidewalks with a prevalence of 11.71%.The The result of the present study shows that the least prevalence of 8.33% was found in playgrounds.
area's most heavily contaminated with Toxocara eggs Clay type soil harboured a higher percentage of are public parks permanently inhabited by dogs and Toxocara eggs when compared with sandy soil, with 24 cats.This report is comparable with results of study of / 225 sandy soil samples being positive for Toxocara Mizagaska, (2000), that the most contaminated areas eggs at a prevalence rate of 10.66%.However, 18/102 were city backyards with 38-53% of soil samples clay type soil samples were positive for Toxocara eggs, positive for Toxocara eggs [18].The presence of with the prevalence percentage of 17.64%.
puppies could increase the probability of finding fertile Similar surveys revealed prevalence ranging from Toxocara spp.eggs in the soil surface, as puppies 2.21% to 40.4% in India [9,10,11].Since the public release more eggs in their faeces than adults.Also, parks and play grounds have free access to pet and stray Toxocara eggs are resistant to environmental conditions animals, they potentially act as source of contaand can remain infectious for years in a favourable mination.Further, street food vendors discard left out environment [19,20].food that attracts the stray and scavenging animals.
Previous investigations of soil contamination by Surprisingly, pets are brought to such public places for zoonotic parasites in public places have focused on the defeacation, thereby contaminating the soil.When prevalence of Toxocara spp.due to the importance of children play over such contaminated soil, the ova visceral larva migrans [2,10,11].Overgaauw [21], could lead to larva migrans in such individuals.In the found that the presence of feral cats, heavily infected present study we found play grounds being less with T. cati (21%) is a complicating factor in the contaminated with the Toxocara eggs than other sites, prevention of environmental contamination.However, as the play ground soil in the study areas were contamination by Ancylostoma spp.should be also composed mainly of sand, which does not retain water considered in these studies.The detection of Ascaris well and the low humidity is lethal to Toxocara eggs.
eggs in a few samples in the present study suggests that Some physical properties of the soil, including the soil was contaminated by human (Ascaris lumbricoides) humidity, oxygenation and compactness, can influence or pig faeces (Ascaris suum).This suggests problems egg survival in the environment [12].
with the basic sanitation in Bareilly city.Although the soil samples used in present study

Conclusion
were collected in the autumn and winter, yet exposure of the soil to prolonged periods of sunlight along with Since, free access of pet and stray animals to the nature of the sandy soil, could contribute to the public places is hazardous, keeping in view public Material and Methodsmodified technique, a centrifugal-floatation technique with the use of Sodium Nitrate (NaNO , d = 1.22) as the 3 Study area:

Site of collection Number of sites Number of Number of examined
Table-1.Toxocara eggs prevalent at different locations in and around Bareilly.

Table - 2
. Toxocara eggs in different soil type Toxocarais recommended.Pet owners must also be educated for spp.eggs in the Krako´w area and two nearby villages, Wiad.regular deworming and the visitors should be made Bali, H,S. and Kaur A.(1997).Prevalence of importance.The knowledge of the areas contaminated Toxocara spp.eggs in the soil of public and private places in with Toxocara eggs will help in the planning of Ludhiana and Kellon area of Punjab, India.epidemiol.sante anim, 31-32.effective measures to prevent the infection.Soil contamination with canine hookworm and round worm ova in Bangalore.Journal of parasitic diseases, 26:107-108.SS designed study, processing and screening of samples, 11.Das, S.S., Kumar, D., Sreekrishnan, R. and Ganesan, R. analysis and interpretation of data and preparation of (2009).Soil contamination of public places, play grounds and residential areas with ova of Toxocara.IndianJ.Vet.Res, manuscript.SNR, SS and MDN collected, processed, 17(2):13-16.screened the samples and drafted the manuscript.12. Xavier, R.I.G., Ramos,B.C. and Santare'm, V.A. (2010).OKR, SCG and AK revised the manuscript.All authors Recovery threshold of Toxocara canis eggs from read and approved the final manuscript.soil.Veterinary Parasitology, 167 :77-80.13.Mandarino-Pereira, A., Silva de Souza, F., Carlos, W.G.L.,