Entamoeba histolytica can cause dysentery

Currently five types of protozoa are of concern: Entamoeba histolytica, Giardia lamblia, Cryptosporidium parvum, Naegleria and Acanthamoeba. Entamoeba histolytica is a microscopic endoparasitic of humans. It is chiefly found in the colon of large intestine.

Entamoeba histolytica, the cause of amoebic dysentery, is spread principally by fecal contamination of water, food, body parts and diverse objects: sexual partners make an epidemiological impact.

It can be transmitted by the poor personal hygiene of food handlers, contamination of ready-to-eat foods such as fruits or vegetables, from drinking water, and by insect vectors such as flies.

Entamoeba histolytica infection is widespread in subtopic areas. Infection begins when trophozoites of Entamoeba histolytica invade the colonic mucosa.

The majority of infected people do not display any pathology, and the parasite exists as a commensal, continuing to multiply and spread. Only a small fraction of the infected individuals show overt symptoms of amebiasis with invasion in the intestinal tissues or in some extraintestinal sites, such as liver.
Entamoeba histolytica can cause dysentery

Traveler’s diarrhea

Ingestion of contaminated food or water makes travel-associated diarrhea the most common health complaint among international travelers.

The early history of the topic of traveler’s diarrhea is tied up with military campaigns, where soldiers classically have suffered more losses from diarrhea and dysentery than from war-related injury. The later history related more to international travelers, expatriates and short-term students spending time in high-risk areas.

 It has been estimated that 30% - 40% of the 50 million people who travel to developing countries every years from the developed parts of the world will experience classic symptoms of traveler’s diarrhea.

Traveler’s diarrhea characterized by a 2 fold or greater increase in the frequency of unformed bowel movement, occurs in as many as 40% of all travelers overseas.

The classical clinical picture in traveler’s diarrhea is the sudden onset of profuse, water diarrhea. The stools are watery, perhaps yellow at the beginning, but later almost colorless and relatively odorless.

The diarrhea may accompanied by cramping, nausea, vomiting and chills. The patients may also complain of muscle and joint pain. Illness was generally seen within the first week of arrival to the high-risk area, with nearly all cases occurring within the first 2 weeks.

The illness lasted between 2 to 5 days and was self limiting, the younger travelers were at greatest risk, and recurrences occurred in about 15% of travelers remaining in the area of risk for 5 weeks.

Children, especially those less than 3 year of age, have a higher incidence of diarrhea, more-severe symptoms and more-prolonged symptoms than adults, with a reported attack rate of 60% for those less than 3 year of age in one study.
Traveler’s diarrhea

Amebiasis

Amebiasis
Amebiasis, as trichinosis, is not a bacterial disease. A single-celled animal (an ameba) cause amebic dysentery in humans. The organism is called Endamoeba histolytica.

Amebiasis varies greatly in symptoms from patients to patient and periodically in severity in the same patient. Diarrhea is a common symptom of the diseases, and it may be persistent and severe, mild and occasional. Abdominal pain, fatigue and fever are sometimes encountered. Incubation lasts from 2 days to several months, but it usually 3-4 weeks.

The control of Amebiasis is essentially matter of good sanitary procedures.

1. Drinking water, water added to foods, and used for washing and sanitizing of equipment and utensils and for irrigation of crops should be portable.
2. Drinking water to be used for foods or for equipment or utensils that contact foods, taken form deep wells, lakes, or ponds, should be tested periodically for bacteriological safety. Although this is not a bacterial disease, it appears to occur when bacteria indicative of pollution with human discharge are present.
   
3. Persons known to have had amebic dysentery should be rigidly excluded from food handling of any kind.

Amebiasis