What is Cryptosporidium?

Cryptosporidium is a single celled protozoan parasite that is found within the intestinal tract and causes an infection known as cryptosporidiosis – a gastroenteritis type infection. There are 6,000 cases of cryptosporidiosis confirmed in the UK each year caused by this waterborne pathogen and it is thought that there are many more unreported cases as the only way to confirm Cryptosporidium infection is by a stool sample. The infection is known to cause vomiting, diarrhea, vomiting and fever. The condition can be contracted by anyone however the condition is particularly harmful to those with a weekend immune system such as children, the elderly or people who’s immune system has been compromised due to a medical condition. There is currently no known treatment for the infection and it can take up to four weeks for the immune system to combat the infection.

Cryptosporidium is infectious and is usually passed on person to person but can also be contracted through water or food. Although the risk for this is lower, it is vitally important that necessary precautions are take to eliminate the infection as there is the potential to affect a large number of people. The pathogen is also infectious when airborne so considerations must also be made in industries that come into contact with steam

Cryptosporidium is usually found in ponds, rivers and lakes where the water may have come into contact with sewage or animal waste. Other areas of risk are private water sources such as boreholes and wells. Once contaminated, the oocyst can live within the water source for weeks, even at low temperatures.

Who is most at risk of contracting Cryptosporidium?
• Swimmers who regularly use pools with insufficient sanitation (Certain strains of Cryptosporidium are chlorine-resistant)
• Child-care workers
• Parents of infected children
• Health care workers and Carers and other people who may be exposed to human faeces
• Backpackers, hikers, and campers who drink unfiltered, untreated water
• People who swallow water from contaminated sources
• People handling infected cattle
What can be used for removal of Cryptosporidium?

Water treatment alone is not guaranteed effective at illuminating the risk of a Cryptosporidium outbreak. The only way to protect against a potential outbreak is to use water treatment in juxtaposition with regular water monitoring as even the most sophisticated water treatment systems cannot guarantee that your water supply will be free from Cryptosporidium.

A filter used to remove Cryptosporidium is a filter that is capable of removing particulates at ≤ 1µm. One filter commonly used for this is a ceramic filter. Some of the more conventional ways of removing bacteria from water are simply not effective at destroying Cryptosporidium due to the unusually thick outer layer of the oocyst. Cryptosporidium is also highly resilient to chlorine therefore using chlorine, as a method of disinfection is ineffective unless it is used in very high doses with a long period of contact time. This may not be appropriate for industrial uses such as within food and drinks production.

Doulton supplies the ceramic filters used by Industrial water equipment, these ceramic filters are capable of removing pathogenic bacteria down to 1µm making them 100% effective at killing Cryptosporidium.

Cartridge filters can also be effective at removing Cryptosporidium. Again, you need to ensure that the are capable of removing particulates of ≤ 1µm

Reverse osmosis units are also fully capable at removing Cryptosporidium from a water source however pretreatments will be necessary for this to work effectively and it may be a more expensive solution to the problem.

As well as filtration, there are other solutions for removing Cryptosporidium. These methods are effective but may not be suitable to every application including those related to human contact or consumption such as swimming pools and food and beverage industry. These chemical solutions involve high doses of chlorine, ozone and chlorine dioxide. These chemicals are strong disinfectants that kill the oocyst as well as other parasites.
Another method used is UV light. The UV light is a physical process, which works by inactivating the Cryptosporidium oocyst breaking it down, killing it and preventing reproduction.

Another very effective and low cost way of killing Cryptosporidium is simply boiling your water. Water which is brought to a rolling boil for ideally three minutes and at least one minute. This method although cheep and very effective may not be appropriate for industrial applications or long-term use.

All of the above methods are equally viable and effective. The appropriate method is all dependent on your intended usage. For more detailed information, call an Industrial Water Equipment engineer for further advice.