Prevalence and distribution of soil transmitted helminths (sth) among asymptomatic school Going children in south chennai, tamil nadu, india

soil transmitted helminth (sth) infections represent a major health problem in poor and developing countries. We conducted a pilot study to determine the prevalence of sth among school going children of Kancheepuram district. Three hundred and fifty eight children in the age group of 5-10 years were examined for STH. One hundred and fourteen of the 358 (40%) were tested positive for various intestinal helminths. The various intestinal helminths are Ascaris lumbricoides, Trichuris trichiura and Taenia species. At least one intestinal helminth was detected in 25.13% (90/358) children and multiple helminth infestation was recorded in 15.08% (54/358). The most common parasitic helminth was A. lumbricoides 60% (84/144) followed by T. trichiura 4.17% (6/144). A. lumbricoides was found as single type infection as well as in association with other helminths in mixed type infection. This study emphasizes the need for improved sanitation and better living conditions for the school-age children in rural areas.

introduction Soil-transmitted helminths (STH) are one of the most important groups of infectious agents and are causing world's major human health problems until now. The commonest parasitic infections reported globally are Ascaris (20%), hookworm (18%), Trichuris trichiura (10%) and Entamoeba histolytica (10%). It is estimated that as much as 60% of the world's population is infected with gut parasites, which may play a role in morbidity due to intestinal infestations. Inadequate hygiene, poor health care systems and facilities, social indifference, social instability, civil war and natural disasters make situations worse. 1 STH are more important among children and in poor or malnourished populations. It has been shown to contribute to anaemia, stunted growth, and underweight and poor school performance. 2 The prevalence and distribution of soil transmitted helminthes (STH) among asymptomatic school going children in Tambaram

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Age -wise infestation rate was 21%, 15% and 5% in the 9 to 10, 7 to 8 and 5-6 year age group respectively. There is no statistically significant difference with respect to age.

discussion
The present study investigated the prevalence and distribution of soil-transmitted helminths among the asymptomatic school going children. The prevalence rate of soiltransmitted helminths was 40% (144/358). In India, the overall prevalence rates ranges from 13-66% with varying prevalence rates for individual parasites. 3  The results of this study indicate that A. lumbricodies was the commonest helminthic parasite in both male (75%) and female (61%) children, followed by T. trichura, 26.2% in male and 36.3% in female children. This may be due to the presence of the source of the infection in the area studied and frequent faeco -oral spread of infection among children. In addition, contamination of soil by human faeces (especially for Ascaris and Trichuris) in combination with a high degree of overcrowding and a low-income level increases the susceptibility to helminthiasis. Similar results were shown by Lindo et al. 6 and Al-Nakkas et al. 8 in Kuwait.
Data analysis reveals a higher percentage in males (54%) than females (27%) which is statistically not significant (p value > 0.92). This is due to the fact that males and females are more exposed to unhygienic conditions in field Age and gender wise prevalence of various types of helminths in the children were shown in Table 2 and 3. In this study, the rate of infestation was comparatively higher among the boys (66.67%) than in girls (33.33%). A p value of > 0.206 [χ 2 = 3.16] reveals no statistically significant difference in the prevalence of A. lumbricoides, T. trichiura, Taenia species between boy and girl children.   Our data are consistent with a direct effect of the lack of sanitation on prevalence/intensity of intestinal helminth infections as suggested by others. 5 Populations living close to each other may have different risks for STH infections if their social economic status and their living conditions differ. For an appropriate control strategy it is important to conduct epidemiological surveys which are able to detect these differences. However, the survey was basically aimed at providing the awareness of STH among school going children and need to improve the standards of living in rural setup which may decrease STH infections.

conclusion
This study shows that intestinal helminths are prevalent in high magnitude among school children of the study area. This calls for the institution of control measures, including treatment of all school -age children, improvement of sanitation and provision of clean water. The impact of each measure would be maximized through a health education programme directed at school children in particular and at community in general.

acknowledGeMent
We would like to thank all the children, their parents, teachers and the school authorities for their co-operation. We also