As a private practitioner my reaction to this disease will be as follows:

The old habit of diagnosing clinical amoebiasis by the presence of cysts of E. histolytica in the stool should be condemned. In fact we are still not very sure which variety of E. histolytica are normal commensals and which are pathogenic. Only if a patient having diarrhoea shows vegetative forms of E. histolytica or a febrile patient with a tender hepatomegaly has a positive serological test in high titres, can the diagnosis of amoebiasis be confirmed. Liver imaging with aspiration and the sigmoidoscopy with mucosal biopsy are other helpful procedures.

Then what is the value of presence of cysts of E. histolytica in a stool? Any food handler or any domestic staff involved in food handling or in fact anybody who is found to have cysts in the stools should be given a course of Diloxanide Furoate in the dose of 500 mg tds for 10 days. It is interesting to note that most of the time these people do not suffer from clinical amoebiasis but can pass on the infection to others. The immunological status of the patient or other factors like pregnancy, administration of steroids etc. possibly decide that who would develop the clinical disease and who would become only a carrier of the disease.

If this is the definition of amoebiasis - that is - presence of cysts of E. histolytica in the stools, then this is an extremely common condition in our country. Why? Since the disease is transmitted by faeco-oral route, bad sanitation naturally is the major factor.

Following are the sources:

1. In big cities it is the contamination of the drinking water pipe with the sewage pipe.
2. Use of sewage polluted water for irrigation.
3. Use of human faeces as a fertilizer.
4. Use of sewage polluted water by the vendors for freshening vegetables and salads.
5. Food sold by the hawkers and the restaurants where the flies have contaminated the same.
6. Food served in top hotels or houses where cooks and servants or the food handlers are carriers and have unhygienic habits of specially not cutting the nails and not keeping them clean.
7. Use of tap water in preparation of ice in refrigerators etc.

The unfortunate part of the spread of this disease is that the chlorination of drinking water of which the public has so much faith in, is not at all effective for killing the E.Histolytica cysts. It is only boiling the water for 10 minutes or the use of a filter (both of which are very costly for an average poor or middle class Indian) which are effective in eradicating the cysts of E. Histolytica. Similarly soaking the vegetables or fruits in boiled water is not enough. These articles should be soaked in a weak solution of Iodine and then rinsed in boiled water.

The conclusion is that in our country it is impossible to carry out the prevention of amoebiasis. Though health education, construction of sanitary systems etc., and other propaganda should be carried out at the Government and Institutional levels, the Indian doctors can help in preventing the spread of the disease only by carrying out the following advice:

Prescribe a course of tablet Diloxanide Furoate as advised above to every person whose stool is found to be positive for cysts of E. histolytica. Since the stool examination is difficult on a large scale it will be better to give the above chemotherapy to all the food handlers every few months.

Metronidazole or Tinidazole are good drugs for treating clinical amoebiasis, but have little role in preventive amoebiasis.

In fact all the patients of clinical amoebiasis should also be given tablet Diloxanide Furoate for 10 days, so that in future they do not become a source of infection to others.

Unfortunately because of poor demand from the doctors Diloxanide Furoate tablets are not freely available in the market, and the combination preparations do not offer enough dose (and duration) in eradicating the cysts!