What are Giardia and Cryptosporidium?
The cysts that crippled Sydney’s water supply in 1998 can still be found in some municipal water supplies. Unlike bacteria, Giardia cysts and Cryptosporidium oocyst are more resistant to conventional water treatment, such as chlorination and ultraviolet irradiation. Cryptosporidium parvum is a waterborne parasite encased in a leathery shell, or oocyst and causes severe flu-like symptoms when ingested. Once ingested, the walls of the oocyst are softened by the digestive fluids in the stomach and small intestine. Four tiny protozoa emerge and immediately begin to reproduce and infect the intestinal lining. This process impairs the small intestine’s ability to absorb water and nutrients, which causes the infected person to expel the oocyst through diarrhoea and vomiting. Water can become infected through contact with infected animal faeces or intestines and will pass freely through water treatment plants as it is not readily killed by chlorine. Cryptosporidium is one of the most resistant
Related Questions
- ISSUE 35: Are the incidence of the protozoan parasites, giardia and cryptosporidium, in streams and surface waters always linked to the presence of livestock ?
- Giardia and cryptosporidium can both make me sick. Which is the hardest to kill?
- Is UV effective against protozoa such as Cryptosporidium and Giardia lamblia?
