Pattern of helminthic infestation in primary schoolchildren of Thiruvananthapuram district

   V. Raman Kutty, C. R. Soman, and K. Vijaya Kumar*

Helminthic infestation is a serious public health problem, especially in areas of low environmental quality and of people of low nutritional status. In the growing stage, children are more susceptible to the ill effects of parasitic attacks, as their need for nutrients is high. In young children, physical and mental development may be affected by mal-absorption, blood and protein loss and diarrhoea generated often by presence of several types of worms in the gut. There is also the risk of complications. Many parasites interfere with the process of intestinal absorption of nutrients. They feed on the nutrients, depriving the child of its sources of nutrition. The child is thus thrown into a state of acute and chronic malnutrition.

The major objectives of the study are the following:

(i)      To estimate the prevalence of intestinal worm infestation in primary schoolchildren in Thiruvananthapuram district, among coastal, midland, highland, and urban schools separately;

(ii)     To study the pattern of infestation and compare it with the profile of helminthic infestations in the past;

(iii)             To initiate control in the selected schools through medical and health education measures.

Discussion

(i)                 Prevalence of worm infestation: Overall, about 58 per cent of specimens examined were positive for some type of ova. Stools from coastal children showed the greatest prevalence, with almost three out of four showing evidence of worms; more than one-half of midland specimens and almost two thirds of highland specimens were also positive. On the other hand, only around one in four of the urban children showed evidence of helminthiasis in stools. The presence of ova in stools seems to be related to both the geographical setting of the locale (highland, midland, coastal or urban), and the socio-economic background of the families. Coastal children are more prone partly due to poor living conditions, and partly to the lack of awareness of hygienic practices on the part of their parents. In the highlands, though natural drainage exists in the locality and density of population is low, factors conducive for low prevalence, our study brings out that intestinal helminthiasis continues to be a major problem in this area. Insensitivity of the parents to children’s hygiene and the children’s frequent exposure to ova-laden soil emerged as important factors in the case studies. Midland specimens showed a lower prevalence than in the other two areas, may be due to comparatively better living conditions and greater awareness on the part of parents. Urban children, in whom helminthiaisis should have been absent, still show a not-so-low prevalence, of greater than one in four. This fact should sensitise us to the low standards of environmental hygiene even in the State’s cities.

(ii)               Types of ova: We specifically looked for four organisms, viz., roundworm, hookworm, whipworm and pinworm.  Roundworms were the major intestinal parasite, accounting for most of the ova found. The dramatic disappearance of hookworm ova from the stools of children of the State becomes evident when we compare this data with earlier reports. This achievement is mostly to be attributed to the wide prevalence of footwear use in the State, even among children. Also, the ova of hook worms being rather fragile, breaking the cycle of re-infection at some point results in their being unable to spread in the population. In contrast, roundworm ova that can live for years in the soil continues to be present in all the sample areas. Spread of whipworm and pinworm has much to do with personal hygiene; and it is observed that whipworm prevalence has not come down in the Thiruvananthapuram district to any great extent.

(iii)             Prevalence in relation to other factors: As we have seen, prevalence is clearly related to geographical and socio-economic factors. Going into the details, we find that the presence of toilets in the house, washing hands with soap after defecation, and before eating, and use of footwear by children, are all behavioural attributes that afford some protection. These may be seen as pointers of a more enlightened lifestyle and not merely as preventive measures practised for their own sake. The evidence for this is in the clear relationship of parents’ educational status with helminthic infestation in children: parents with at least seven years of schooling had children with much lower levels of infestation. However, even in the urban school where most children came from families of educated parents, one in four stool specimens showed round worm ova. We are tempted to suggest that one of the principal reasons may be the consumption of raw, uncooked vegetables, which are grown in the soil. However, as we have not gone into this question, we cannot be sure in this regard. Perhaps an examination of washing of raw vegetables for helminthic ova may throw light on this question.

More importantly, this finding could mean that however good the personal measures of hygiene, our environmental hygiene still leave a lot to be desired.  Improvements can be brought about only by community and civic action and not solely through efforts of individual families.

(iv)              Implications of the findings: Despite the presence of round worm ova in the gut of a large proportion of the children, it does not seem to pose a major health hazard, since from anecdotal evidence we know that instances of acute intestinal obstruction and other medical catastrophes precipitated by a large number of worms in the gut are almost non-existent in recent times. Thus, our findings should not cause any alarm. Moreover, the almost complete absence of hookworms and pinworms, which can be potentially far more distressing, is indeed an encouraging sign. However, the presence of round worms almost universally under all situations should cause concern for our environmental quality. Continuing presence of whipworm ova in stools should also alert us to the need for improvement in personal hygiene. Action for improving this is imperative. In this regard, we find that the prevalence of intestinal worms in primary schoolchildren may be used as an indicator of the environmental status of a village. Local bodies should use worm surveys in schools, which can be completed very easily and at small cost, to monitor periodically the improvement taking place in the living conditions in the areas concerned.

* Dr. V. Raman Kutty is Executive Director and Dr. C. R. Soman is Chairman of Health Action by People, an NGO. Dr. K. Vijaya Kumar is Assistant Professor, Department of Community Medicine, Thiruvananthapuram Medical College.