Tuesday, January 5, 2010

Health Care and E Coli

The news media loves to report on sensational stories, and the more drastic the news the higher ratings are estimated to be for any type of story. Health care news is top of the table coverage for media outlets especially now. On occasion, you will see reporters talk about outbreaks of E. Coli in the nation's food supply. According to the Centers for Disease Control (CDC), Escherichia Coli (abbreviated as E. coli) are a large and diverse group of bacteria. Although most strains of E. coli are harmless, others can make you sick. Some kinds of E. coli can cause diarrhea, while others cause urinary tract infections, respiratory illness and pneumonia, and other illnesses. Still other kinds of E. coli are used as markers for water contamination—so you might hear about E. coli being found in drinking water, which are not themselves harmful, but indicate the water is contaminated. It does get a bit confusing—even to microbiologists.

According to About-ecoli.com, More than 700 serotypes of E. coli have been identified. The different E. coli serotypes are distinguished by their “O” and “H” antigens on their bodies and flagella, respectively. The E. coli serotypes that are responsible for the numerous reports of contaminated foods and beverages are those that produce Shiga toxin (Stx), so called because the toxin is virtually identical to that produced by another bacteria known as Shigella dysenteria type 1 (that also causes bloody diarrhea and hemolytic uremic syndrome [HUS] in emerging countries like Bangladesh). The best known and most notorious Stx-producing E. coli is E. coli O157:H7. It is important to remember that most kinds of E. coli bacteria do not cause disease in humans, indeed, some are beneficial, and some cause infections other than gastrointestinal infections, such urinary tract infections.

Shiga toxin is one of the most potent toxins known to man, so much so that the Centers for Disease Control and Prevention (CDC) lists it as a potential bioterrorist agent (CDC, n.d.). It seems likely that DNA from Shiga toxin-producing Shigella bacteria was transferred by a bacteriophage (a virus that infects bacteria) to otherwise harmless E. coli bacteria, thereby providing them with the genetic material to produce Shiga toxin. Although E. coli O157:H7 is responsible for the majority of human illnesses attributed to E. coli, there are additional Stx-producing E. coli (e.g., E. coli O121:H19) that can also cause hemorrhagic colitis and post-diarrheal hemolytic uremic syndrome (D+HUS). HUS is a syndrome that is defined by the trilogy of hemolytic anemia (destruction of red blood cells), thrombocytopenia (low platelet count), and acute kidney failure. Stx-producing E. coli organisms have several characteristics that make them so dangerous. They are hardy organisms that can survive several weeks on surfaces such as counter tops, and up to a year in some materials like compost. They have a very low infectious dose meaning that only a relatively small number of bacteria (less than 50) are needed “to set-up housekeeping” in a victim’s intestinal tract and cause infection.

The Centers for Disease Control and Prevention (CDC) estimates that every year at least 2000 Americans are hospitalized, and about 60 die as a direct result of E. coli infections and its complications. A recent study estimated the annual cost of E. coli O157:H7 illnesses to be $405 million (in 2003 dollars) which included $370 million for premature deaths, $30 million for medical care, and $5 million for lost productivity. The CDC has estimated that 85% of E. coli O157:H7 infections are foodborne in origin. In fact, consumption of any food or beverage that becomes contaminated by animal (especially cattle) manure can result in contracting the disease. Foods that have been sources of contamination include ground beef, venison, sausages, dried (non-cooked) salami, unpasteurized milk and cheese, unpasteurized apple juice and cider, orange juice, alfalfa and radish sprouts, lettuce, spinach, and water.

According to FamilyDoctor.org, symptoms start about 7 days after you are infected with the germ. The first sign is severe abdominal cramps that start suddenly. After a few hours, watery diarrhea starts. The diarrhea causes your body to lose fluids and electrolytes (dehydration). This makes you feel sick and tired. The watery diarrhea lasts for about a day. Then the diarrhea changes to bright red bloody stools. The infection makes sores in your intestines, so the stools become bloody. Bloody diarrhea lasts for 2 to 5 days. You might have 10 or more bowel movements a day. Some people say their stools are "all blood and no stool." You may have a mild fever or no fever. You may also have nausea or vomiting. If you have any of these symptoms -- watery, bloody diarrhea, cramps, fever, nausea or vomiting -- get to your doctor right away. The most common complication is called hemolytic uremic syndrome. People with this problem get hemolytic anemia (which is a low red blood cell count), thrombocytopenia (which is a low platelet count) and renal failure (which is kidney damage).Hemolytic uremic syndrome is more common in children. It can cause acute renal failure in children. This problem starts about 5 to 10 days after the diarrhea starts. People with this problem must go to a hospital for medical care. The diagnosis is made by finding E. coli in a stool culture. If you have bloody diarrhea, see your doctor as soon as possible. Your doctor will do a culture to find out if you have E. coli in your intestines. The culture has to be taken in the first 48 hours after the bloody diarrhea starts.

You can help prevent E. coli infection by handling and cooking meat in a safe way, according to FamilyDoctor.org. For your protection, follow these rules:
--Wash your hands carefully with soap before you start cooking.
--Cook ground beef until you see no pink anywhere.
--Don't taste small bites of raw ground beef while you're cooking.
--Don't put cooked hamburgers on a plate that had raw ground beef on it before.
--Cook all hamburgers to at least 155°F. A meat thermometer can help you test your hamburgers.
--Defrost meats in the refrigerator or the microwave. Don't let meat sit on the counter to defrost.
--Keep raw meat and poultry separate from other foods. Use hot water and soap to wash cutting boards and dishes if raw meat and poultry have touched them.
--Don't drink raw milk.
--Keep food refrigerated or frozen.
--Keep hot food hot and cold food cold.
--Refrigerate leftovers right away or throw them away.
--People with diarrhea should wash their hands carefully and often, using hot water and soap, and washing for at least 30 seconds. People who work in day care centers and homes for the elderly should wash their hands often, too.
--In restaurants, always order hamburgers that are cooked well done so that no pink shows.

Now, if the meat is ground, you have a much more risky situation, according to the University of Kansas. Any bacterial cells originally only on the surface of the meat, will now be distributed throughout the preparation. It is very important in this case to thoroughly cook the meat - until the juices run absolutely clear. Actually, the latest recommendation is that each hamburger pattie must reach an internal temperature of 160 degrees F. Apparently, viable (living) E. coli have been isolated from hamburger meat cooked to the point of "juices running clear". This procedure is very similar to that one would use to cook pork or perhaps a Thanksgiving turkey, e.g., observe the internal temperature of the meat before it is served. Just remember, if you like your meat and especially hamburgers, "rare", you are taking a significant risk. It is also important to realize that meat may not be the only source of contamination with such bacteria or other dangerous bacteria - any contaminated water source or contaminated person can load these bacteria onto vegetables, etc. So, it is a good idea to be careful with everything - wash fresh fruit, vegetables, etc., thoroughly before eating. This last statement is very important, since as mentioned above, recent cases of O157:H7 infection have been found associated with non-pasteurized apple juice. This organism is apparently spreading around and about. So, it is important to be vigilant and aware.

According to the Mayo Clinic, for illness caused by E. coli O157:H7, no current treatments can cure the infection, relieve symptoms or prevent complications. For most people, the best option is to rest and drink plenty of fluids to help with dehydration and fatigue. Avoid taking an anti-diarrheal medication — this slows your digestive system down, preventing your body from getting rid of the toxins. Follow these tips to prevent dehydration and reduce symptoms while you recover:
--Clear liquids. Drink plenty of clear liquids, including water, clear sodas and broths, gelatin, and juices. Avoid apple and pear juices, caffeine and alcohol.
--Add foods gradually. When you start feeling better, stick to low-fiber foods at first. Try soda crackers, toast, eggs or rice.
--Avoid certain foods. Dairy products, fatty foods, high-fiber foods or highly seasoned foods can make symptoms worse.

The vast majority of cases involving E. coli are preventable. Use common sense and the tips listed in this blog to help keep you safe.

Until next time. Let me know what you think.

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