Worm infestations were known to be a very common problem in the days gone by. It has been reduced drastically in the last couple of decades, mainly due to improved living standards and proper hygienic practices. There are very many myths and false beliefs associated with intestinal worms in children. None of them have a proper scientific basis.

Worm infestations in children used to be a major perennial problem in many areas of Sri Lanka just a couple of decades ago. It was not uncommon for children to be seen in out-patient departments of hospitals, at general practitioner surgeries and in hospital paediatric wards with all types of problems associated with worm infestations. There are a considerable number of worms that could secure an existence in the human intestine. Out of these, only a certain number have been found in the children of our land. Among the intestinal worms, round worms, hook worms, thread worms and whip worms are the ones that have been commonly found to be prevalent in Sri Lanka. Most of the worm infestations are associated with poor personal hygiene or lack of awareness of wearing protective footwear. The incidence of worm infestations have been reduced by improved living standards of the populace and good personal hygiene and habits inculcated by programmes of public health education. As a result, worm infestations and ensuing complications have been pushed way down in the list of important childhood medical problems in recent times. However, there are a multitude of false beliefs and myths associated with the phenomenon known as intestinal worms in children.

Intestinal worms are parasites that live in a symbiotic relationship with the human host. They survive by either taking up some of the nutrition that is taken in by the individual or by actively extracting the necessary components of nutrition from the wall of the intestine of the affected individual. Worms do not just spontaneously appear in the intestine nor are they brought on by children consuming sweets. They have to get into the body actively from the surrounding environment. This occurs when food or water contaminated with eggs of these worms is taken in or in certain other cases, larvae of the worms actively penetrate the unprotected skin of the soles of feet due to walking without protective footwear. As most of the worms live in the intestine and their eggs are passed in the faeces, the main basic reason for spreading infestation with worms is the lack of toilets, improper use of latrines, poor personal hygiene and leaving food unprotected from contamination.

Round worms are rather long round bodied worms that live in the small intestine of humans. They obtain their nourishment from the food that is taken in by the affected individual and live a purely parasitic existence. Humans contract round worm infestations by swallowing the worm eggs in food or drink that has been contaminated by infected faeces from an individual who already has the illness and is excreting the worm eggs in the faeces. Further complications with these worms are caused by sheer numbers of them in the intestine. A few worms in the intestine do not cause significant problems. However, very large worm loads tend to interfere with the child’s nutrition as most of the food taken in are utilised by the worms themselves. In addition, large numbers of these worms when present in the intestine produce physical effects such as obstructions to the normal flow of the intestinal contents. The worms can get rolled up together to form a mass or a ball that could produce intestinal obstruction. Occasionally the worms migrate to other areas such as the bile ducts and cause significant problems. Children who have a significant load of worms may also pass some of them in the faeces.

Hookworms are another group of worms that inhabit the upper parts of the small intestine. The larvae of these worms get into the body by penetrating the skin of the soles and toes of feet when walking barefoot on soil contaminated by faeces from an individual with the disease. The eggs that reach the soil hatch to form the larvae that can penetrate intact skin. Once the larvae get into the body, they go through a process of development and finally end up in the upper small intestine. There they attach themselves to the wall of the intestine and survive by sucking blood from the human host. A large worm load of hookworms can lead to a very significant daily blood loss and anaemia in the affected child. It was not uncommon in the not too distant past to see children who were as pale as a sheet and who were in heart failure due to extremely severe anaemia resulting from hook worm infestations.

Thread worms are also contracted by contaminations of food and water by eggs and larvae. These worms too live in the large intestine and migrate to the anus producing intense irritation around the anus. Eggs are laid around the peri-anal region and they hatch to produce larvae. These worms could actually be seen in the area of the anus and appear as small dots and threads which wriggle and are mobile. The infestation spreads through contaminated hands and clothes. A characteristic form of presentation is that of irritation in the area around the anal region which manifests as scratching.

Whipworm infestation is contracted by swallowing the eggs of these worms through contaminated food and water. The worms reside in the large intestine and produce a chronic diarrhoea with blood and mucous. The chronic and severe nature of the diarrhoea leads to malnutrition and even prolapse of the rectum where the rectum and lower intestine comes out of the anus and remains like a protruding mass.

There are some other types of worms that could infest humans. Those include several types of tape worms and in such cases, the complaint may be that the child is passing segments of these tape worms. All these are quite rare now and are even thought of only when there are compelling reasons. In addition, children could also be infected by several other types of worms that usually occur in other animals such as dogs, cats monkeys etc. They produce unusual symptoms and need special investigations to sort out the problem.

There are very many myths and false beliefs regarding human intestinal worms. Many types of folklore are also interwoven into several of the misconceptions regarding worm infestations. Many parents believe that children get worms from drinking milk and that certain types of worms arise in the body from the milk that is drunk by the child. Pure milk by itself does not contain worms or predispose to worm infestations unless the milk is contaminated with worm eggs. Some others believe that sugar and sweets induce worms in the body. There is no truth whatsoever in these beliefs. The only way for any item of food to cause worm infestation is by that article of food being contaminated with worm eggs.

Some others believe that the position that a child assumes during sleep such as sleeping prone with the bottom pointing upwards, restlessness during sleep, teeth grinding while asleep and some protuberance of the tummy are all indicators of worm infestation. Protuberance of the abdomen in toddlers is due to inadequately developed muscles and poor tone in the muscles of the abdominal wall in this age group. Many parents also attribute lack of interest in food and apparent loss of appetite to worm infestations. Some others believe that certain types of skin rashes and some slightly whitish patches on the skin, especially of the face, are due to worms. Some of these are normal transient changes in the skin. There is no scientific basis to sustain any of these contentions. Apathy, lack of interest in the surroundings and play are also attributed to worm infestations. True enough, in conditions like hook worm infestations, the ensuing anaemia can lead to these manifestations. As long as the child is not pale and anaemic, it is unlikely that these manifestations are due to worms.

The diagnosis of definitive worm infestation depends on either passing of worms in stools, the finding of the eggs or larvae in the anal region or by the findings of worm eggs in the stools on microscopic examination. It is important to point out that worm eggs are passed only intermittently in the stools, even in children with rather high worm loads. Thus a single negative test does not exclude worm infestations.

When a proper worm infestation has been diagnosed it needs to be treated adequately. There are several drugs that are effective against the common worms that are found in children. Different drugs have their own schedules of calculation of the dosages, exact ways in which they have to be given and the duration of the full course of treatment. It is important to follow instructions accurately. However, worm treatment is very often doled out rather indiscriminately by many doctors for minor, unrelated and trivial complaints. This is an unscientific and unrewarding action as the original complaints remain in the majority of cases. There is a very common habit among parents to regularly "de-worm" their children, often as regularly as every three months. This is based on the premise that they contract worm infestations regularly. This is a misconception and such practices are totally unnecessary manoeuvres which will perhaps only make drug companies happier and richer. However, children from socially deprived and impoverished backgrounds with poor sanitary facilities may benefit from regular worm treatment. These cases are only a few and it is not justifiable to treat all children, including those even from the higher socio-economic strata, in this way. Our country spends a considerable chunk of foreign exchange on importation of a large number of drugs and it is certain that the importation of some of the drugs used for treating worms could be drastically reduced by evidence based scientific practices. g

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