Introduction Balantidium coli is a parasitic species of ciliate protozoan responsible for the disease Balantidiasis. Balantidium coli is the largest protozoan and the only ciliate known to parasitize humans.
Balantidiosis is a zoonotic disease. It is acquired by humans via the fecal-oral route from the normal host, the pig, where it is Asymptomatic. Water is the vehicle for most cases of B alantidiosis of Balantidiosis.
Geographical Distribution The protozoa are found worldwide Bolivia Papua New Guinea Philippines
HOST Humans are the principle host. It is also reported in Dogs It is common in monkeys and pigs.
Site of Infection Following are the site of Infection :- 1 ) Caecum 2 ) Large Intestine
Morphology Balantidium coli has 2 developmental stages . T rophozoite stage Cyst stage
Trophozoite Oval pointed at anterior end 50-130um long Covered in cilia Non-infective Reproduce by binary fission and conjugation Micronuclei and macronuclei
Cyst Spherical 40-60um across Covered with thick, hard cyst wall with cilia Infective Non-reproductive Macronuclei
2) Cyst stage
Trophozoite Shape Oval, pointed at anterior end Size 50-130 m m long Surface Covered in cilia Infectious Not infective Reproduction By binary fission or conjugation Nuclei Macronucleus and micronucleus
Cyst Shape Spherical Size 40-60 m m across Surface Covered with thick, hard cyst wall with cilia Infectious Infective Reproduction Non-reproductive Nuclei Only macronucleus
Life cycle Life Cycle Completed in a single host Natural hosts Pigs Accidental host Route : Ingestion Reproduction: asexual and sexual
Life Cycle Life cycle is as follow : The cyst is the infective stage of Balantidium coli life cycle. Once the cyst is ingested via feces-contaminated food or water, it passes through the host digestive system. There, excystation takes place in small intestine. Excystation produces a trophozoite from the cyst stage.
The motile trophozoite then resides in the lumen of the large intestine, feeding on intestinal nutrients. Trophozoites multiply by asexual binary fission or sexual conjugation The trophozoite may become invasive and penetrate the mucosa of the large intestine. Trophozoites are released with the feces, and encyst to form new cyst Cysts in the environment are then ready to infect another host.
Sign and Symptoms Acute ,even hemorrhagic Diarrhea Ulceration to gut wall Dysentery Colitis Abdominal pain
Diagnosis Examination of patient`s stool Biopsy sigmoid scope is used to visually inspect the last sections of the large intestine
Treatment Three drugs are commonly used and administered orally Tetracycline Metronidazole Iodoquinol
(1) Tetracycline's 500 mg four times daily for 10 days (2) Metronidazole 750 mg three times daily for 5 days (3) Iodoquinol 640 mg three times daily for 20 days
Control and Prevention Avoid ingestion of material contaminated with animal feces Prevention and control Sanitary disposal of human and pig feces Treatment of infected pigs Prevention of fecal contamination of food and water