Question

Which is not a symptom of Entamoeba histolytica?
A. Relapsing fever
B. Abdominal pain
C. Blood in stool
D. Irregular bowel

Answer 1

Hint: Humans could be infected by bacteria, viruses, fungi and protozoans. Infectious and non-infectious diseases are the two major classifications of diseases. Infectious disease can be transmitted from one person to another like AIDS. Non-infectious diseases cannot be transmitted. For example; cancer.

Complete step by step answer: Entamoeba histolytica causes amoebiasis (amoebic dysentery). Entamoeba histolytica is a protozoan parasite. The parasite was discovered by Lamble. The pathogenic nature was discovered by Losch. The large intestine of humans is the habitat of this pathogen. The characteristic feature of the cysts of this pathogen is the presence of chromatoid bodies. The mode of transmission of the disease can be through the faecal-oral route, sexual transmission, and vectors like flies and cockroaches. Houseflies are the mechanical carriers and play a role in transmitting the parasite from faeces of an infected person to food and food products. The cyst after passing unaltered through the stomach liberates the active parasites in the intestine. There it starts a normal life. The cyst is unaltered in the stomach because it is resistant to the action of gastric juice. It is digested by the action of trypsin in the intestine. The pathogen eats red blood corpuscles. In amoebic dysentery, the patient passes blood along with faeces and feels pain in the abdomen, and also suffers from cramps.
Hence, the correct answer is option A.

Note: Some important points to remember are listed below:
i. Metronidazole and Tinidazole are used to treat amoebic dysentery.
ii. The tetra nucleate cyst is the infective stage.
iii. Magna and minuta are the two forms of Entamoeba histolytica.