When drinking water is untreated….. [Archives:1997/44/Health]

November 3 1997

Of the several parasitic diseases which the local population should be aware of there is one like ameobiosis, specifically giardiasis which has been contracted in Yemen irregardless of the season. First of all the amoebae causing the disease is classified as a protozoan in the animal kingdom, a unicellular organism that divides by fission not by mitosis as human cells do. The protozoan is a flagellate, meaning it has a tail like flagella which enables it to swim. There are other protozoans that are not flagellates like the dysentery amoeba which is a much more serious parasite and will be treated in another article. Both organisms can survive in a cyst form, that is a form which enables them to survive droughts and inhospitable conditions. The organism can be found in contaminated water and is easily contracted by careless householders especially villagers who do not boil their water supply efficiently. Water sources might be contaminated by impure effluents or untreated water effluents. Such could be the case in villages where people wash and get their home supply at the same stream. The organism unlike the dysentery one does not invade the body tissue. It enters the alimentary tract and swims its way to the intestinal lining where it attaches to the villa cells with a ventral depression that acts like a suction cup. It can cover extensive areas of the intestinal mucosa or inner lining thus causing its clinical symptoms, diahorrea, indigestion and stomach cramps. The only way that it can be transmitted is through the feces in its cyst form. The ameba can be diagnosed by its classic cyst form which have four nuclei i.e. is a tetra nucleate. Also when a large amount of these are present in the intestine the loose bowel movement caused is fatty and contains a yellow mucous. For amoebiasis in general, emetine chloride or antibiotics such as tetramyacin has been implicated as a cure. The alkaloid can be isolated from the dried roots of the ipecac plant of the madder family native to South America. For chronic cases, that is cases which continue for a length of time, organic iodides and arsenics are suggested. For giardiasis on the other hand nitro-imidazoles have been proven more efficient. Martin Dansky B.Sc.