FOOD POSIONING, IT’S CAUSES, EFFECT AND CONTROL
CHAPTER ONE
1.1    INTRODUCTION
Food poisoning might be described as a food borne diseases or food borne illness. Food that contains a toxin, chemical or infectious agent (like a bacterium, virus, parasite or prion) and causes symptoms in the body are considered types of food poisoning by most investigators.
Those symptoms may be related only to the gastrointestinal tract causing vomiting or diarrhea or may involve other organs such as the kidney, brain or muscle. (Charles, 2011).
 Tribe et al., (2008) explains that food poisoning usually arises from improper handling, preparation or food storage. Good hygiene practice before, during and after food preparation can reduce the chances of contracting an illness. There is a consensus in the public health community that regular hand washing is one of the most effective defenses against the spread of food borne disease. The action of monitoring food to ensure that it will not cause food poisoning or diseases can also be caused by a large variety of toxins that affect the environment. Food borne illness can also be caused by substances like poisonous mushrooms or pathogenic microorganisms.
 Tribe et al., (2008) further explains that bacteria are common cause of food borne illness. He further points out that in Nigeria during 2000, the individual bacteria involved were as follows.
Campylobacter jejumi 77.3%, salmonella 20.9%, Esherichia coli 1.4% and all other less than 0.1%.
In the past, bacterial infections were thought to be more preventive because few places had the capability to test for the particular agent.
Symptoms for bacterial infections are delayed because the bacteria need time to multiply. They are usually not seen until 12 – 72 hours or more after eating contaminated food.
 Marases et al., (2007) highlighted that food poisoning/food borne diseases is caused by eating food or drinking beverages contaminated with bacteria, parasites or viruses. He further states that harmful chemicals can also cause food borne disease. If they have contaminated food during harvesting or processing. Food poisoning can cause symptoms which include diarrhea, fever, vomiting, abdominal cramps, and dehydration. Most food borne infections are undiagnosed and unreported, though the center for disease control and prevention estimates that every year, about 76 million people in the United States become ill from pathogens or disease causing substance in food, (Katon and Chessbrought 2000).
 Joffe, et al., (2002) pointed out that harmful bacteria are the most common cause of food borne illness or food poisoning. Some bacteria may be present in foods when they are purchased. Raw foods are the most common sources of food poisoning because they are not sterile. Examples includes: raw meat and poultry that may have become contaminated during slaughter. Sea food may become contaminated during harvest or through processing. One in 10,000 eggs may be contaminated with salmonella spp inside the egg shall. Products such as spinach, lettuce, tomatoes, spronts and melons can become contaminated with Salmonella, Shigella or Esherichia coli. during growth or through processing and distribution. Contamination may also occur, during food preparation in a restaurant or at home kitchen.
 Robert, et al., (2007) states that the most common contamination from handled food is by a group of viruses known as the Norwalls. Infected kitchen workers can contaminate a salad or sandwich as they prepare it, if they have the virus on their hands.
1.2       CAUSES OF FOOD POISONING
Mayo, (2011) explains that contamination of food can happen at any point during its production, growing, homewashing, processing, storing, shopping, or preparing. Cross contaminate the transfer of harmful organisms from one surface to another is often the cause. This is especially troublesome for raw, ready – to – eat food, such as salads or other product. Because these foods are not cooked, harmful organisms aren’t destroyed before they can cause food poisoning.
The major causes of food poisoning are as follows, bacteria, viruses and parasitic organism.
The organisms are as follows:
-      Campylobacter
-      Clostridium butulinum
-      Esherichia Coli 0157H7
-      Circadian Limbia
-      Hepatitis A
-      Listeria
-      Rotavirus
-      Noroviruses (Norwalk like viruses)
-      Staphylococcus aures
-      Shigella
  TABLE I: COMMON CONTAMINANTS, FOOD AFFECTED AND MEANS OF TRANSMISSION.
Contaminants     Onset of symptoms     Foods affected and means of transmission
1. Camplobacter    2 to 5 days    Meat and poultry contamination occurs during processing of animal feaces contact meat surfaces. Other source includes unpasturized milk
2. Clostridium butulimum    12 to 72 hours    Home canned food with low acidity, improperly canned commercial foods, smoked or salted fish, potatoes baked in aluminum foil and other foods kept at warm temperature for too long.
3. Esherichia Coli 0157H7    1 to 8 days    Beef contaminated with feaces during slaughter spread mainly by undercooked ground beef. Other sources include unpasturized milk and apple cider, alfalta sprouts and contaminated water.
4. Staphylococus aures.    1 to 6 hours    Meat and prepared salad cream, sauces and cream filled pastries can be spread by hand contact, coughing and sneezing.
5. Shigella    24 to 48 hours    Sea food and raw, ready –to – eat produce can be spread by an infected food handlers.
6. Rotavirus    1 to 3 days    Raw, ready –to- eat produce can be spread by an infected food handler.
7. Listeria    9 to 48 hours    Hot dogs, luncheon meats, unpasturized milk and cheeses and unwashed raw produce can be spread through contaminated soil and water.
8. Norovirus. (Norwalk like viruses)    12 to 48 hours    Raw ready to eat produce and shellfish from contaminated water can be spread by an infected food handler.
Source: Mayo, (2011)
 According to Linda (2011), food poisoning can affect one person or group of people who all ate the same contaminated food. It more commonly occurs after eating at picnics, school cafeterias, large social functions or restaurant. The germs may get into the food you eat (called contamination) in different ways which includes:
Meat or poultry can come into contact with bacteria from the intestine of an animal that is being growing or shopping can contain animal or human waste and food handling or preparation in grocery stores, restaurants or homes.
 Arnon, et al., (2007) explain that salmonella is a common cause of food borne illness, particularly is undercooked chicken and chicken eggs. Food borne illness, commonly called “food poisoning” is caused by bacteria, toxins, viruses, parasite, and prions.
 Williams (2009), also explained that roughly 7 million people die of food poisoning each year, with about 10 times as many suffering from a non fatal case. The two most common factors leading to cases of bacteria food poisoning are cross contamination of ready – to - eat food from other uncooked foods and improper temperature control. Less commonly, adverse reaction can also occur if chemical contamination of food occurs. For example, improper storage or use of non-food grade soaps and disinfectants.
Again, when food is cooked and left out for more than 2 hours at room temperature, bacteria can multiply quickly. Most bacteria grow undetected because they don’t produce a bad odour or change the colour or texture of the food. Freezing food shows or stop bacteria growth but does not destroy bacteria.
1.3    FOOD POISONING AND FOOD SPOILAGE ORGANISMS
Danilo (2009), states that food poisoning (known as food borne illness or food borne disease is any illness that results from eating contaminated food.
Bacteria and viruses are the most common cause of food poisoning. The symptom and severity of food poisoning vary depending on which bacteria or virus that has contaminated the food.
The bacteria and virus that causes the most illness, hospitalizations and death includes;
-      Salmonella
-      Norovirus
-      Compylobacter
-      E.coli
-      Lesteria
-      Clostridium perferingens
1.4    FACTORS THAT ENCOURAGES FOOD POISONING
The common factor that encourages food poisoning are as follows:
i.      Contamination by food utensil
ii.      Improper storage of food at room temperature
iii.     Inadequate cooking and re-heating of food
iv.     Poor personal hygiene of food handlers
v.     Cross contamination from raw to ready to eat foods.
 1.      CONTAMINATION BY FOOD UTENSIL: Live tissue on animal is essential sterile but it is during food preparation that it can become contaminated at any stage of the process. The most critical stages are skinning and evisceration as it is the hide and intestines that contains the animal micro-flora along with organism present in the feaces and soil. Abattoirs hygiene must be kept to a very high standard to present contamination from faecal mutter and other carcess like knife, plates etc. E coli is most commonly associated organism.
2.      IMPROPER STORAGE OF FOOD AT ROOM TEMPERATURE: Proper storage of food can help reduce and prevent food contamination. After grocery shopping, store perishable foods in the refrigerator should be kept at 40 degree Fahreheit. Some bacteria such as listeria can survive and grow even at low temperature. Thus even foods stored in the refrigerator won’t last forever. Throw away all foods that have passed their expiration date or hake been opened for longer than recommended.
3.      INADEQUATE COOKING AND RE-HEATING OF FOOD: Both raw and cooked food must be regularly checked to prevent microbial growth. Food that is being retreated must be reheated to a temperature of approx 700°c to ensure any organism growing are destroyed prior to consumption. The most common food poisoning organism Campylobacter jejuni is most often associated with undercooked chicken
4.      POOR PERSONAL HYGIENE OF FOOD HANDLERS: Unhygienic food handling promotes contamination and spread of food borne illness/food poisoning. Unwashed hands can transfer harmful microbes to your food. Wash your hands with soap and water before and after handling food. Raw food as poultry, seafood and meat contain microbes that can spread to your cooking surface and other ingredients if you do not handle them properly. Prevent contact with raw meat and fresh food and secure raw juice from leaking and contaminating other ingredients by using plastics containers, wash your hands, cutting boards, utensils and kitchen surface immediately after you handle raw meat.
5.      CROSS CONTAMINATION FROM RAW TO READY TO EAT FOOD: Although it may not seem so but fresh vegetables and fruits can also contain microbes ad washing your fresh foods before eating or using them in salads helps prevent contamination. The surface of these foods can contain microbes acquired from a variety of sources during harvest, storage and transport. Use warm water to rinse all clean vegetables and fruits and use a brush for foods that contain dirt such as potatoes, carrots and mushrooms.
1.5    COMPLICATIONS OF FOOD POISONING
Hughes, et al., (2009) states that dehydration is the most common complication. This can occur from any causes of food poisoning. Less common, but much more serious complications depend on the bacteria that are covering food poisoning.
These may include:
-      Arthritis
-      Bleeding problems
-      Damage to the nerves system.
-      Kidney problem
-      Swelling or irritation in the tissue around the heart.
 Robert (2007), points out that in some people especially children, hemolytic uremic syndrome (HUS) can result from infection by a particular bacteria especially pathogenic Echerichia coli and can lead to kidney failure and death. HUS is a rear disorder that affects primarily children between the ages of 1 and 10 years and is the leading cause.