27/02/2021
Balantidium coli is a cosmopolitan parasitic-opportunistic pathogen that can be found throughout the world. Pigs are its reservoir hosts, and humans become infected through direct or indirect contact with pigs. In rural areas and in some developing countries where pig and human f***l matter contaminates the water supply, there is a greater likelihood that balantidiosis may develop in humans. The infection may be subclinical in humans, as it mostly is in pigs, or may develop as a fulminant infection with bloody and mucus-containing diarrhea; this can lead to perforation of the colon. The disease responds to treatment with tetracycline or metronidazole. Balantidiosis is a disease that need never exist given access to clean water and a public health infrastructure that monitors the water supply and tracks infections. Its spread can be limited by sanitary measures and personal hygiene.
Balantidium sp. and Nyctotherus sp. are ciliated protozoans which are frequently encountered in chelonians stools. They are considered as normal inhabitants of the normal chelonian digestive-tract flora and play a usefull role in the digestion of cellulose. Therefore, in most cases, they appear to cause their hosts little or no distress. However, from time to time, due to a variety or reasons (such as dietary mismanagement; drugs treatments; …), these protozoans may outnumber their normal proportions resulting in pathogenic consequences (severe irritation of the intestinal walls). The symptoms may range from acute diarrhea, resulting in dehydration and weight loss into chronic cases with a complete loss of normal digestive-tract flora and inanition as a result of an inability to digest and metabolise the food consumed
Cysts are the infectious stage responsible for transmission of balantidiasis. The host most often acquires the cyst (Figure 1) through ingestion of f***lly contaminated food or water. Following ingestion, excystation occurs in the small intestine, and the trophozoites colonize the large intestine
trophozoites reside in the lumen of the large intestine of humans and animals, where they replicate by binary fission, during which conjugation may occur. Trophozoites undergo encystation to produce infective cysts. Some trophozoites invade the wall of the colon and multiply. Some return to lumen and disintegrate. Mature cysts are passed with f***s into the environnement.
rotozoan organisms can represent a major hazard to captive collections of chelonia but not all occurrences are pathogenic. The best prevention is good hygiene. Special attention should be paid to food handling and feeding routines. Cleaning and disinfection of husbandry infrastructure is highly recommended on a regular basis.
Preventive screening of f***l (and urine) samples for pathogenic agents may help in preventing built-up of severe protozoan outbreaks and tortoise losses in captive conditions. If pathogenicity is suspected, veterinary treatment should be sought ASAP.
However, effective treatment exists, but detection and diagnosis of the "real" pathogens (e.g. Hexamita sp.) is primordial, before treatment is installed (if not, more harm than good can be done!).