Cryptosporidium – How Does it Affect Your Health and Why is it So Hard to Destroy?
It’s hard to say for sure how many Americans are infected by cryptosporidium per year. This is so because many are infected without consulting a doctor and because the cysts are so hard to detect in the laboratory. A small quantity of cysts in water can be hard to find in a laboratory. Yet a small number of cysts can infect the person who drinks them.
The fact that it resists disinfection and that it can even get through well-operated water treatment systems, means that it is a very big problem facing the clean water industry. What then are the symptoms of the disease known as cryptosporidiosis?
How Can Cryptosporidium Affect My Health?
It only takes a relatively few cysts to infect a person. The incubation period of the illness, cryptosporidiosis, is about one week but can be anywhere from 2 to 25 days. The cyst germinates and reproduces causing symptoms such as severe diarrhea, gas, stomach cramps, nausea, headaches and even slight fever. The degree of intensity varies with the person. Some people in fact have no symptoms. On the other hand, for those with low resistance (HIV/Aids patients, transplant patients, cancer patients) or those vulnerable to dehydration (as small children and pregnant women), the attack of this parasite can be life threatening.
The symptoms last normally a week or two but can last up to a month or longer. There are really no good drugs to cure cryptosporidiosis. Some drugs help with the symptoms. What is important is to replenish your body fluids through drinking water or receiving intravenous fluids, if necessary.
Why Is The Cryptosporidium Cyst So Hard To “Search and Destroy”?
The cysts are so small that they are difficult to find even under a microscope. They are particularly hard to find in water where it takes only a relatively few cysts to infect a person. The Environmental Protection Agency set new standard for this parasite to be met by 2001, for water systems serving the majority of U.S. populations (those serving surface water to 10,000 or more). The new standard says that the parasite should be totally disinfected (killed) or removed by filter from the water. Water treatment systems are required to report the presence of cysts in your tap water.
The cyst is hard to destroy because it is extremely hardy and durable. It can get through chlorine disinfectant treatment in city water systems and make it to your tap. The cyst is encased in a shell-like cover which once in the stomach, is dissolved by the stomach acids and in turn reeks havoc with the intestines and multiplies itself to be discharged in the stool.
The best way to remove it is using the right kind of filter. A filter that is certified to remove cryptosporidium by NSF International is recommended. NSF International has a useful search tool on their web site where you can indicate the contaminants that you want to remove from your drinking water. They will then tell you which filters they have certified to remove those contaminants. The contaminant to check is “Cyst Reduction”.
By: David G Langford
Categories: Water Borne Illnesses Tags: Cysts, Drinking Water, Stomach Cramps
The Importance of Water Filter Cartridges
Suppose that you are a new mother, one who has just read that ingestion of water containing nitrates can damage the health of an infant. Although your husband has just left for the store that stocks water filter replacement cartridges, you wonder if you and your husband should go out and purchase some bottled water. Would such an action eliminate from the baby’s diet all possible sources of nitrate?
No it would not. A parent who wants to avoid giving food or water with nitrates to an infant needs to do more than simply taking the time to purchase bottled water. Once nitrates make their way into the soil, they can travel down to the level of the ground water. By using water filter cartridges, a homeowner can all but abolish any concerns about nitrates in the tap water.
Suppose that you are a new father, one who has set aside time to look at the available water filter replacement cartridges. Whether you are driving to a location that stocks such cartridges, or whether you are examining the online information on such cartridges, you probably have one question foremost in your mind: “How much do these water filter cartridges cost?”
The consumer who needs to replace the existing cartridge in a water filter system typically wants to find a discounted product. Indeed there are water filter replacement cartridges that can be purchased at a lower than normal price. Of course, someone who hopes to choose wisely, when selecting a replacement cartridge for a water filter system, should study more than just the price of the available cartridges.
Once a cartridge needs to be replaced, the health of those drinking the water that flows through the old cartridge could be in danger. In order to do away with that danger, an old cartridge needs to be replaced in a fast and efficient manner. That fact should be weighed against the asking price for any of the replacement cartridges on the market today.
By the same token, consumers need to understand that not every cartridge that has been made for use in a filter system is identical to all the other cartridges on the market. Tap water can contain many different types of contaminants. By purchasing wisely, a homeowner can feel secure about buying the right sort of cartridge for his or her water filter system.
The homeowner might want to buy a carbon block cartridge. The carbon in those cartridges acts like a sponge. It soaks-up the contaminants in the water. That carbon comes from natural sources-coconut shells, coal products and wood.
A homeowner might live in an area that was recently inundated by flood waters. Such a homeowner would have reason to worry about the presence of bacteria or other contaminants in the tap water. That homeowner might want to buy a water filter cartridge that could aid with the detection of chlorine in the drinking water.
Whenever a homeowner looks to well water as a source of tap water, that homeowner must be especially conscious of the dangers posed by flood waters. Flood waters increase the likelihood that contaminants could enter the well water (and thus the tap water). After a flood, a homeowner should not forget about the importance of water filter replacement cartridges.
Of course, even a homeowner without a well should consider investing in a water filter system. That homeowner should not ignore the importance of water filter cartridges. When functioning properly, such a cartridge can eliminate asbestos, copper, lead and mercury from the tap water. Still, when a homeowner ignores the need to replace such a cartridge, he or she puts at risk the health of all those residing in the home with the old cartridge.
Failure to heed advice about water filter replacement cartridges can cause the inhabitants in a home to get dry skin or GI problems. They might also report to a physician the development of reproductive problems. Water contaminants can cause any of those problems.
A tap that delivers pure, good tasting drinking water can free a homeowner from concerns about contaminants that might impair the health of those in the home. A water filtration system that receives a replacement cartridge on a regular basis, one that uses activated carbon filters and ion exchange micron filtration, can bring safe water into the home.
For that reason, insurance against possible health problems can be found among the available water filter cartridges. A guarantee of continued benefits from a water filter system with such a cartridge goes only to those willing to look, on a regular basis, at the available water filter replacement cartridges.
Categories: Water Filters Tags: Arsenic, Asbestos, Chlorine, copper, cryptosporidium, Cysts, lead, mercury, nitrates
Giardiasis (Giardia Lamblia)
What is giardiasis?
Giardiasis (gee-ar-die-a-sis with a soft “G”) is an infection of the small intestine that is caused by the parasite, Giardia intestinalis, also known as Giardia lamblia. It is the most common cause of parasitic gastrointestinal disease, and it is estimated that up to 2.5 million cases of giardiasis occur each year in the US. Up to 20% of the world’s population is chronically infected with Giardia lamblia.
Giardia lamblia exists in two forms, an active form called a trophozoite, and an inactive form called a cyst. The active trophozoite attaches to the lining of the small intestine with a “sucker” and is responsible for causing the signs and symptoms of giardiasis. The trophozoite cannot live long outside of the body, therefore it cannot spread the infection to others. The inactive cyst, on the other hand, can exist for prolonged periods outside the body. When it is ingested, stomach acid activates the cyst, and the cyst develops into the disease-causing trophozoite. It takes ingestion of only ten cysts to cause infection. Trophozoites are important not only because they cause disease, they also produce cysts that exit the body in feces and spread infection to others.
Cysts of Giardia are present in the feces of infected persons. Thus, the infection can be spread from person to person by contamination of food with feces, or by direct fecal-oral contamination. Cysts also survive in water, for example in fresh water lakes and streams. As a result, giardiasis is the most common cause of water-borne, parasitic illness in the United States. Domestic mammals (for example, dogs, cats, calves) and wild mammals (for example, beavers) can become infected with Giardia; however, it is not clear how often domestic or wild mammals transmit giardiasis to humans. Giardiasis also has occurred as outbreaks from recreational water sources such as swimming pools, water parks, and hot tubs, most likely because of an infected user rather than a source of water that was contaminated.
Who is at risk for giardiasis?
Giardiasis occurs where there is inadequate sanitation or inadequate treatment of drinking water. Giardiasis is one of the causes of “travelers diarrhea” that occurs during travel to less-developed countries , for example the Soviet Union, Mexico, Southeast Asia, and western South America. Giardiasis is a common cause of outbreaks of diarrhea in day-care centers because of the high probability of fecal-oral contamination from children; the children, their families, and day care center workers, all are at risk for infection. In fact, children are three times more likely to develop giardiasis than adults. Hikers exploring back-country areas who drink from contaminated fresh water lakes also are at risk for developing giardiasis. Homosexuals who practice anal/oral sex also may become infected.
What signs and symptoms does giardiasis cause?
The most common manifestations of giardiasis are diarrhea and abdominal pain, particularly cramping; however, diarrhea is not invariable and occurs in 60 to 90% of patients. Other common manifestations include bloating, nausea with or without vomiting, malaise, and fatigue. Fever is unusual. The severity of the symptoms may vary greatly from mild or no symptoms to severe symptoms. Stools may be foul smelling when the Giardia interferes with the absorption of fat from the intestine (malabsorption). The illness or the malabsorption may cause loss of weight.
Symptoms and signs of giardiasis do not begin for at least seven days following infection, but can occur as long as three or more weeks later. In most patients the illness is self-limiting and lasts 2-4 weeks. In many patients who are not treated, however, infection can last for several months to years with continuing symptoms. Children with chronic infection may fail to thrive. Some patients recover from their giardiasis, with or without treatment, but symptoms continue, perhaps because there has been bacterial overgrowth within the small intestine
How is giardiasis diagnosed?
The best single test for diagnosing giardiasis is antigen testing of the stool. For antigen testing, a small sample of stool is tested for the presence of Giardial proteins. The antigen test will identify more than 90% of people infected with Giardia. Giardia also can be diagnosed by examination of stool under the microscope; however, it takes three samples of stool to diagnose 90% of cases. Despite requiring three samples of stool, microscopical examination of stool identifies other parasites in addition to Giardia that can cause diarrheal illness. Therefore, microscopical examination of stool has value beyond diagnosing giardiasis, for example, it can diagnose other parasites as the cause of a patient’s illness.
Other tests that can be used for diagnosing giardiasis are collection and examination of fluid from the duodenum or biopsy of the small intestine, but these require a good deal of discomfort. The string test is a more comfortable method for obtaining a sample of duodenal fluid. For the string test, a gelatin capsule that contains a loosely-woven string is swallowed. One end of the string protrudes from the capsule and is taped to the patients outer cheek. Over several hours, the gelatin capsule dissolves in the stomach, and the string uncoils, with the last 12 inches or so passing into the duodenum. In the duodenum the string absorbs a small amount of duodenal fluid. The string then is untapped from the cheek and is removed. The collected duodenal fluid is expressed from the string and is examined under the microscope. Although more comfortable than some of the other tests, it is not clear how sensitive the string test is, for example, does it diagnose 60% (not very good) or 90% (very good) of cases of giardiasis.
How is giardiasis treated?
The most common treatment for giardiasis is metronidazole (Flagyl) for 5-10 days. It eradicates the Giardia more than 85% of the time, but it often causes gastrointestinal side effects such as nausea and a metallic taste as well as dizziness and headache. Despite its effectiveness, metronidazole is not approved by the FDA in the US for treatment of giardiasis.
The only drug approved for treating giardiasis in the U.S. is furazolidone (Furoxone) for 7-10 days. It is approximately as effective as metronidazole. Tinidazole is available outside the U.S. and is highly effective at treatinggiardiasis(>90%). It also can be given as a single dose and is well tolerated. Quinacrine is very effective for treating giardiasis but is no longer available in the U.S. Paromomycin and albendazole, though effective, are less effective than other treatments.
Occasionally, treatment fails to eradicate Giardia. In such cases, the drug may be changed or a longer duration or higher dose may be used. Combination therapy also may be effective (e.g., quinacrine and metronidazole).
How can giardiasis be prevented?
* Drink only water that has been treated in established treatment facilities.
* If there is any doubt about the adequacy of the treatment of water, boil the water or filter it through a filter with a pore size of <1 micrometer.
* Do not drink from fresh water streams or lakes without boiling or filtering the water.
* Do not use ice or drink beverages made from tap water that may be contaminated.
* Do not brush teeth with tap water that may be contaminated.
* Do not eat uncooked or unpeeled fruits or vegetables grown in conditions in which contamination with Giardia might occur.
* Wash hands before eating food, after changing diapers, using the bathroom, or touching pets.
* Avoid oral/anal sex.
Medical Author: Jay W. Marks, MD
Categories: Water Borne Illnesses Tags: Cysts, Diarrhea, trophozoite
