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Foodborne Illnesses

At some point in our lives, we've all gotten sick from eating contaminated or undercooked food. You can reduce your risk of developing foodborne illnesses by following a few safety tips. Here's more about the common types of foodborne illnesses and what you can do to protect your gut.

1. What are foodborne diseases?

Foodborne illnesses are caused by organisms or harmful chemicals in the food we eat and drink. Most of these illnesses are caused when certain bacteria, viruses or parasites contaminate food. Others occur when food is contaminated by harmful chemicals or toxins. Over 250 different foodborne diseases have been described. It's not surprising that since most of these infections or chemicals enter the body through the stomach and intestines, the most common symptoms are nausea, vomiting, diarrhea and abdominal discomfort.

2. What are the most common types of food borne illnesses?

Around a hundred years ago, typhoid fever, tuberculosis and cholera were some of the most common diseases caused by bacteria contaminating food and water. Improvements in food processing and water treatment have almost eliminated these problems in the United States at the present time. Today, other bacteria and viruses have become common causes of foodborne disease, including Campylobacter, Salmonella, E. coli O157:H7, Shigella, Clostridium botulinium, Hepatitis A and Calciviruses. A bacteria called Vibrio parahemolyticus, and a parasite called Cyclospora have been found to be the cause of a few recent outbreaks of food borne illnesses.


Campylobacter is the most common bacteria causing food borne diarrhea in the world. These bacteria live in the intestines of birds, and can often contaminate raw poultry such as chicken. Eating undercooked chicken, or eating food contaminated by juices from raw chicken are common ways of contracting this illness. Diarrhea that is often bloody, abdominal cramps and fever are common symptoms. Most people recover from Campylobacter diarrhea with no special treatment. The illness can also be treated with antibiotics such as erythromycin, ciprofloxacin or azithromycin. Rarely, patients can develop arthritis after an infection with Campylobacter. A small number of people develop a type of paralysis called Guillain-Barre' syndrome 2-4 weeks after recovering from Campylobacter infection.

Escherichia coli O157:H7

Escherichia coli (E. coli) bacteria are normally found in everyone's colon, and most types of E coli cause no problems at all. Certain types of E. coli can however cause serious illness, most commonly diarrhea. E. coli O157:H7 is a certain type of E. coli that lives in the intestines of mammals such as cattle. Humans become ill when they eat food contaminated by feces of animals infected with this organism. Hamburger meat seems to be a common source, as the grinding process allows organisms that were only on the surface of meat to be mixed throughout. Also, one infected cow can contaminate a large amount of hamburger as meat from many cattle is often mixed together. Outbreaks of E. coli O157:H7 have also been cause by eating contaminated salami, lettuce and alfalfa sprouts, or drinking unpasteurized milk and apple juice, and contaminated well water.

E. coli O157:H7 can cause severe and bloody diarrhea with painful abdominal cramps. Most people recover without problems in 5 to 10 days. Antibiotics are not particularly helpful. Less than one in twenty patients, most commonly children, can develop a severe complication with low blood count, bleeding, and kidney failure, called hemolytic uremic syndrome.

Enterotoxigenic E. coli is another type of E. coli that can cause severe watery diarrhea. It is very common in developing countries, where it's often spread on unwashed fruits and vegetables, and in drinking water. It is probably responsible for the majority of traveler's diarrhea, and is very likely the leading cause of childhood diarrhea in developing countries.


Salmonella is a bacterium found in the intestines of birds, reptiles and mammals. It can be spread through eating raw poultry, eggs, meat, and unwashed fruit. A person with this infection usually develops fever, diarrhea and abdominal cramps. Most people get better on their own, and do not need medication. Some sicker patients require antibiotics, intravenous fluids and hospital admission. In people with weakened immune systems, salmonella can get into the bloodstream and cause severe illness and even death. Occasionally, people recovering from salmonella infection can develop develop irritated eyes, painful joints and pain with urination, a condition called Reiter's syndrome. Some people infected with salmonella can have no symptoms at all, but become chronic carriers who can spread disease to others. "Typhoid Mary" Mallon, for example, was a cook in the early 1900's, who was never sick with salmonella, but had salmonella bacteria in her stool. Over the course of many years, many people she cooked for became ill, probably from bacteria passed to food from her hands.


Shigellosis, also known as bacillary dysentery, is caused by Shigella bacteria. It is also spread through eating contaminated food and drink. Persons with this infection develop fever, bloody diarrhea, and abdominal pain. Although patients can usually recover without any specific treatment, many patients are treated with antibiotics once they are diagnosed.


Botulism is a disorder caused by a toxic chemical produced by a bacterium called Clostridium botulinum. This bacteria grows best in sealed containers such as cans that have not been heated enough to kill the botulinium spores. The bacteria grows best where there is little or no oxygen. It produces a toxin that can cause paralysis, breathing failure, and even death. Patients ingesting this toxin can develop double vision, drooping eyelids, slurred speech, difficulty swallowing, and difficulty breathing.

3. What foods are most likely to carry illnesses?

Uncooked meat, raw eggs, and unpasteurized milk are the most likely foods to be contaminated. Foods such as ground beef, pooled raw eggs or unpasteurized milk, which are prepared by combining sources from many different animals, are especially problematic, as a whole batch can be contaminated by one infected animal. Vegetables that are eaten raw are also a problem, as they can be contaminated by washing with impure water or by fertilization with manure from infected animals. Raw shellfish are easily contaminated by sewage because these animals are filter feeders that feed by straining large quantities of seawater.

Even properly prepared food can be cross contaminated when juices from raw foods are dripped onto cooked food or when utensils or cutting boards used for raw food are also used for cooked food.

4. How can we prevent food borne illnesses?

The Centers for Disease Control has a few simple recommendations for how to decrease the risk of developing a foodborne disease.

  1. Cook meat, poultry and eggs thoroughly
  2. Separate cooked and uncooked food. Avoid cross-contamination by not using platters or utensils contaminated by raw foods for cooked foods. Put cooked foods on clean platters, not the ones that held the raw meat.
  3. Chill leftovers promptly. Don't leave food out for more than 4 hours
  4. Clean produce. Wash hands before preparing food and immediately after handling raw foods.
  5. Report suspected food borne illness to the local health department.


5. What are the organisms and other contaminants of most concern today?


Cryptosporidium is an organism first noticed as a problem in the 1980's. It is a parasite that lives in the intestines of infected animals. It can get into drinking water when heavy rains wash animal wastes into reservoirs, and it is extremely resistant to disinfection with chlorine. The symptoms of infection include stomach cramps and diarrhea. There is no good treatment, but people with healthy immune systems will recover without any treatment after approximately 14 days. For patients with weakened immune systems, such as those infected with HIV, the disease can be severe, and sometimes can lead to death.

Although there was a major outbreak in Milwaukee in 1993 during which 400,000 people were infected and 40 people died, "crypto" outbreaks are extremely rare: There have been only six documented outbreaks in the United States.


Giardia is another parasite that usually infects human through drinking water. It also lives in the intestinal tracts of animals, and can get into surface water similar to cryptosporidium. It commonly infects hikers who drink untreated water from lakes and streams, and is not an uncommon disease in travelers. Giardia also causes abdominal cramping and diarrhea. Although most people recover uneventfully in 1 to 2 weeks, it can cause chronic illness, especially in persons with compromised immune systems. Fortunately, this infection can be treated with medication. Like Cryptosporidium, Giardia is resistant to chlorine disinfection.

E. coli and fecal coliforms

E. coli and other similar stool 'coliform' bacteria levels are often reported in the news. Although these organisms themselves usually do not cause significant illnesses, they are found in human feces. When these bacteria are found in water supplies, they suggest that the water may be contaminated with human waste.


Arsenic can naturally be found in water in low levels, but high levels can be caused by contamination from manufacturing or mining operations. High levels can cause vomiting, abdominal pain, diarrhea, jaundice and difficulty swallowing. Chronic exposure to low levels can cause skin cancer, cirrhosis and liver cancer.


Lead can leak into drinking water from old pipes, or can be found in water as a result of mining operations. It can cause low blood count, mouth ulcers, constipation, and abdominal pain. In children it can cause delays in physical and mental development.

Disinfection byproducts

Disinfection byproducts are produced when substances such as chlorine, which are used to disinfect the water supply, bind with other chemicals found in water. Although testing has suggested that very high levels of disinfection byproducts can cause cancer in laboratory animals, the EPA has been unable to link the low levels of disinfection byproducts found in American water supplies to any problems.

6. What should you do if you develop a food borne or water borne illness?

Most persons with food borne or water borne illness recover spontaneously. Vomiting and diarrhea can lead to dehydration, so replacing lost fluids and chemicals in the blood are very important. When the diarrhea or vomiting is severe, it's best to use oral rehydration fluids such as pedialyte or oralyte, as juices or even sport drinks such as Gatorade do not have enough important minerals. Bismuth subsalicylate (Pepto-Bismol) may help slow down the symptoms. Diarrhea medication such as loperamide (Imodium) can be used, but if you have a fever or blood in the stools, this medication can actually make things worse and should not be used. If you develop fever over 101.5, dizziness, dry mouth, bloody diarrhea, or if the diarrhea lasts for more than 3 days, you should see a doctor. Suspected food or waterborne illnesses should be reported to your local health department.

If it happens

Even the best nutritional foundation is not going to completely prevent the occasional upset. When it happens I reach for either the Lightning Colloidal Silver or the ProBiotic with FOS. They work differently, and I use either one or the other, never both together. The Lightning Colloidal Silver would be used with the thought of directly killing any bacteria, virus or fungus you have in your system. You would later follow up with ProBiotic with FOS to repopulate your system with the good bacteria your body thrives on. The ProBiotic with FOS works differently. By flooding your body with good bacteria you crowd out and eliminate the bad bacteria without upsetting your body’s balance.

James A Butler MD FACP, CAPT MC USN, Chief, Gastroenterology Service, National Naval Medical Center
Dr Greg Martin, Chief, Infectious Disease Service, National Naval Medical Center
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