Water Quality – Food Hygiene Essentials

Food spoilage is really nothing more than a natural deterioration of organic matter. Everything in nature has to be broken down so that it can once again become part of the composition of soil. All of the various natural processes that participate in the spoilage of organic material are ultimately directed toward this aim.

Odor. Bad odor is a symptom of food spoilage. Foods that have a bad odor should be thrown out. We have already gone into the causes of foul refrigerator odor with regards the spilage of food. Yet there is another factor that we should take into consideration when talking about foul odors of food and that is that the odors can be soaked up by foods which have not spoiled and make them disagreeable to eat. In saying that, this problem does not only pertain to food which has spoiled. Nobody would like to eat a piece of cake that has adopted the odor and taste of smoked salmon, for instance. This is a major problem in the home kitchen. Luckily there are now products available that help to reduce the severity of refrigerator odor and foul taste transfer between foods. Now you can buy a refrigerator purifier that will prove invaluable in the prevention of refrigerator odor. This product is a real food saver. Small air filters for fridges are also available.

When we define food spoilage we can say that spoilage of food pertains any disagreeable change in the nature of food from the normal condition that we expect. These changes may compromise food hygiene. We are able to distinguish these changes through use of our senses. For instance, food may change visually, it may change in smell, to the touch or in taste. In saying that, we use some forms of what technically amounts to food spoilage, in a controlled way, to achieve a desired effect, as in Camembert cheese for instance. We crave the runiness of the cheese that is produced by specially selected bacteria and mould to produce an effect which many of us find pleasing to eat. Other examples of controlled food deterioration include Danish blue, Gorgonzola, Stilton and many other forms of cheese. We also tenderize meat such as game by jugging it or purposely speed up the deterioration process of meat when we inject lactbacillus bacteria into steak to mimic the ageing process. In short and in technical terms, food spoilage works for us easily as much as it works against us.

Nevertheless, food does spoil because once the fruit of vegetable has been picked or the animal has been slaughtered, the natural processes and defences of the organism are compromised and exposure to the outside environment causes a number of inevitable changes to occur.

The factors which bring about these changes include, air and oxygen, light, moisture, microbial growth factors and ambient temperature. Some of these changes indicate poor food hygiene and cross contamination and others point to chemical reactions and changes due to physical phenomina. Let’s go through the various causes.

Air and oxygen: Air comprises of about eighty percent nitrogen and about twenty percent oxygen. The level of oxygen in the air is too great for most organisms and therefore organisms have developed strategies to counter the harmful effects of oxygen. Our lungs are lined with a substance called surfactant. Surfactant provides a necessary barrier between the tissue of the lung and the oxygen in the air to counteract the caustic effect of the oxygen upon the lung tissue. Our bodies and the bodies of other organisms produce anti oxidants to counter other undesirable reactions of oxygen with substances called free radicals. By binding to free radicals, anti oxidants prevent reactions which are harmful to our bodies. When an organisms no longer has the support of it’s various physiological support systems, the chemical make up of the organism will start to react with the oxygen in the air.

Micro organisms which require the presence of oxygen in order to metabolize organic tissue, such as aerobic bacteria and moulds, are able to colonize those areas of the flesh which are exposed to the air. The will form colonies upon the food and start to metabolize the flesh of the organism and divide at a rate of one division every twenty minutes per bacterial cell. In some cases as few as one thousand bacteria can be enough to contitute a food hygiene risk.

Enzymes, particularly oxidizing enzymes, which react with oxygen also aid the process of food spoilage. In vegetables enzymes such as catase and peroxidase cause the familiar browning of the flesh of foods such as apples and potatoes. Enzymes are substances which speed up chemical reactions and enzymatic reaction with oxygen in organic matter causes the degeneration of the matter to hasten considerably. In cooking a rapid heat treatment known as blanching is used to cancel these enzymatic reactions. Enzymatic changes do not usually render food inedible but if combined with microbial infestation such as mould or certain bacteria the ingestion of such spoiled food would constitute a food hygiene risk.

Water: water is the most abundant substance in nature. All organisms are made up of at least seventy percent water. The water within an organism when it is alive is termed as bound water because it is chemically connected to other substances within the body. All living organisms maintain a certain level of chemical concentration. This is said to mimic the concentration of sea water from which all living organisms originate. Concentrated fluids flow around the cells and each cell contains within it a carefully controlled liquid environment. The balance between the concentration of the fluids which flow around the cell and the fluid which exists within the cell is carefully regulated by the central control system of the organism, whether it be plant or animal. In higher organisms this process is called homeostasis.

Once a plant or an animal has been cut into smaller parts, the tissues whose fluid environment was once carefully controlled are now exposed to the environment. When the organism’s flesh comes into contact with moisture a physical phenomenon occurs. All substances in nature try to match their concentration levels to other substances around them, This is called diffusion. The flesh of an organism, when exposed to water will soak up the water in an attempt to dilute the concentration levels within the flesh of the organism to the concentration levels around it. This may cause the cells of the organism to explode by being too full of water. This form of tissue deterioration is a major cause of food spoilage. This intake of moisture into the tissue of the food source is the perfect vector for micro organisms to infest it. This is a very good example of how food spoilage occurs and food hygiene breakdowns happen.

In addition, excess “free” water within or around the cell gives bacteria the perfect medium in which to operate. In bacterial terms this is like a super highway in which bacteria are able to spread throughout the flesh of an organism. Water within an organism can be controlled by a) dehydration, b) freezing or c by the addition of food preservatives.

Light: Spoilage of food which is caused by light is called photo degeneration. All food is exposed to light at some time or another. Light can be either natural light or artificial light. Light, like all other forms of energy is made up of different wave lenghts. At the outer ends of the light spectrum we have infra red and ultra violet light which can vary in intensity in different parts of the world. These forms of light radiation are known to be harmful and can cause dead and live tissue to react in negative ways.

Exposure to light sources can cause foods to change in nature. Pigments may change, as may vitamin levels, fats and proteins. In solid foods the density of the material such as in meat may block deep penetration of light and therefore the effects of light may only cause changes to happen on the surface of the product. In liquids light penetration can be much deeper and therefore the effects of photo degeneration can be much more substantial.

Microbial growth. Micro organisms play a vital role in the balance of nature. Bacteria and other types of microbes haves each evolved to fill a specific niche. Some bacteria have developed a symbiotic relationship relationship with living organisms and some have developed a parasitical relationship. Healthy organisms manage to keep parasitical bacteria at bay through their immune systems and homeostasis. However, parasitical bacteria are constantly on the look out for signs of weakness and it is their job to bring about the rapid demise of sick organisms and to ensure that they are re cycled back into the environment through the process of tissue deterioration and degeneration. In prehistoric times man did not store much food. He ate from hand to mouth and so food did not have much time to go off. Modern man, because of his lifestyle, needs to store food and to do this he needs to effect a different kind of environmental control in comparison to prehistoric man.

In a previous chapter I mentioned that psicrophilic bacteria can cause food spoilage at low temperatures. In cold climates landscapes freeze for many months and animals find it difficult to survive. Weaker animals die during the winter months and remain frozen until the beginning of the thaw in spring. Although thawed a carcass may remain too cold for many types of bacteria to develop and it is for this reason that certain bacteria adapted to this niche so that the detioration of the carcass could begin. This process helps to ensure that the period of time during which more pathogenic bacteria infest the carcass and hence spread into the environment is considerably lessened. This is the function and importance of psicrophilic bacteria in nature. We can control the undesirable effects of psicrophilic bacteria in our cold stores through the implementation of a good hygiene regime.

In general, sources of food contamination come from the environment particularly from, animal wastes, soil, water and air. Here the “Four stages of food hygiene” come into play. Great care must be taken to make sure that food comes from safe sources, that food does not come into contact with other bacterial sources, that bacteria does not have conditions for growth and that tools and work surfaces are kept free from bacteria. food hygiene regime and temperature is all critical here. Don’t make mistakes or cut corners and bacteria will not develop.

Temperature. Temperature is probably the single most important environment which we can control to prevent the spoilage of food. Temperature regulates several changes in the nature of organic matter. Firstly it slows down chemical reactions within the food. Secondly it can prevent the ggrowth development of bacteria or destroy bacteria through cooking, Temperature regulation can control the destruction of vitamins and prevent dehydration and ripening of food.

However, temperature need to be professionally controlled. Over freezing can cause surfaces to crack of the development of ice crystals at microscopic levels can puncture cells causing the flesh to become soft and pulpy. Pigment can be lost and chemicals within the food may react and loose much of their nutritious value. This process is commonly called freezer burning.

In cold stores vegetables and fruit are best held at temperatures of around 10 degrees Celsius. meats should be chilled to four degrees Celsius and frozen food should be stored at -18 degrees Celsius for a period not exceeding six months in most cases. Aaways make sure that you follow manufacturers storage instructions. If in doubt don’t be afraid to contact the manufacturer or importer to get their advise.

A few weeks ago a leading Israeli fruit juice manufacturing plant had several hundred tons of water melon concentrate condemned by the ministry of heath on the pretext that there were unacceptable contaminants within the juice.

The concentrate in question was destined for use on the home market where it is used by the ice cream and iced lollie factories to manufacture a popular range of water melon flavored products. This set back has put additional pressure on a market sector which is already struggling to survive the current market recession.

Israel has suffered several consecutive years of very low rainfall. The sea of Galilee which is the major fresh water reservoir for Israel and it’s neighbours has reached dangerously low levels and as a result of this crisis water prices have risen several fold. As a result of this new state of affairs the profit margins in which vegetable and fruit growers operate have been cut even further and it is really uncertain from year to year if it will be worth growing anything at all.

The jordan valley which enjoys a milder winter than many other parts of Israel is famous for producing early fruit and vegetable harvests both for the home and export markets.

Seemingly, some of the areas water melon growers took it upon themselves to irrigate this years water melon harvest that was intended for industry with grey water instead od fresh water. The logic behind this decision being that grey water does not contain more contaminants than those already presant in ordinary soil.

What is not clear is if the water used for irrigation was indeed just grey water or if the suppliers of the grey water added certain quantities of first stage black water filtrate to the grey water that was being supplied to the farmers. It is also possible that the farmers used grey water for the initial stages of germination and consequent stages before the development of the water melon itself, switching over to fresh water once the melon began to develop. In any case, whatever the sequence of events was, contaminants entered the melons.

Samples of the water melon concentrate were tested both for chemical and microbial contaminants and found to test positive for both categories of contaminates within the concentrate. the concentrate was deemed to be a risk to public health and presented a food hygiene problem. The water melon concentrate was condemned and will not be used to make the iced products that it was intended to make.

The case is being looked into more closely by the public prosecutors office and charges are expected to be issued to those responsible for taking these regretable discisions to used contaminated water for growing water melons.

What is listeriosis?
Listeriosis is a bacterial infection caused by the bacterium Listeria monocytogenes. Until several years ago it was thought that this bacteria only infected animals but it is now accepted that humans are also at risk from this disease. While many bacteria are generally seen to infect specific locations within the human body, Listeria may infect many different locations, such as the brain or the spinal cord membranes or the bloodstream.

Classification:
L. monocytogenes is a gram positive, non-spore forming, motile, facultatively anaerobic, rod shaped bacterium. It is catalase positive, oxidase negative, and expresses a Beta hemolysin which causes destruction of red blood cells. This bacterium exhibits characteristic tumbling motility when viewed with light microscopy. [6] Although L. monocytogenes is actively motile by means of peritrichous flagella at room temperature (20-25C), the organism does not synthesize flagella at body temperatures (37C). [7]

Who gets listeriosis?
Anyone can get this disease, but those at highest risk for serious illness from this bacterium are newborns, the elderly, people with weakened immune systems, and pregnant women. Healthy adults and children occasionally get infected with Listeria, but they rarely become seriously ill. Listeria Monocytogenes is classified as an intracellular paracite. This means that it invades and lives within cells of the body thereby managing to evade the body’s immune system. Infection by as few as 1000 individual bacteria is considered enough for the disease to take hold. When listeric meningitis occurs, the overall mortality may reach 70%; from septicemia 50%, from perinatal/neonatal infections greater than 80%. In infections during pregnancy, the mother usually survives.

When do Listeria infections occur?
Infections occur throughout the year. Although most cases occur sporadically, food-borne outbreaks of this disease do frequently occur. Poor food hygiene and poor personal hygiene conditions are responsible for many of the recently recorded outbrakes.

How is listeriosis spread?
Listeria bacteria are widely distributed in nature and can be found both in water and soil. Infected animals may also serve as sources of contamination. Unlike other organisms, Listeria can be spread through several different methods. Ingestion or food-borne transmission of the organism, such as through the ingestion of unpasteurized milk or by the eating of contaminated vegetables, is often a source of many cases. In newborn infections, the organism can be transmitted from mother to fetus in utero, or directly to the fetus at the time of birth through the contact of the fetus’ blood supply with that of the mothers. Direct contact with the organism can cause lesions on the skin.

What are the symptoms of listeriosis?
Because listeriosis can affect many different parts of the body, the symptoms vary. For meningoencephalitis, the onset can be sudden with fever, intense headache, nausea, vomiting and signs of meningeal irritation. In other body locations, various types of lesions at the site of infection are the primary symptom. In most cases, Listeria infection causes fever and influenza-like symptoms resembling a host of other illnesses.

How soon after exposure do symptoms of listeriosis appear?
Listeriosis has an extremely variable incubation period. It can range from 3 to seventy days, but symptoms usually will typically appear within a month of infection.

How is listeriosis diagnosed?
Specific laboratory tests are the only way to effectively identify this disease. Since many cases may be mild, the disease may be much more common than is realized.

Are there any unusual features of listeriosis?
Listeria infections are a significant risk for pregnant women, who may not experience obvious symptoms. Infection of the fetus can occur before delivery and can cause abortion as early as the second month of pregnancy, but more often in the fifth and six months. An infection later in pregnancy may cause exposure during birth, sometimes resulting in infection of the newborn child which may be fatal.

Does past infection with Listeria make a person immune?
Past infection does not appear to produce immunity.

What is the treatment for Listeria infection?
Several antibiotics are effective against this organism. Ampicillin, either on it’s own or in combination with other types of antibiotics, is frequently used.

What can be done to prevent the spread of Listeriosis?
Since the organism is widly distributed throughout nature, basic sanitary measures such as only using pasteurized dairy products, by only eating cooked meats and washing hands thoroughly prior to the preparation of foods offer the best protection against infection by this disease.

In addition, the following recommendations are for persons who are categorized to be at high risk of infection, such as pregnant women, the elderly and persons with compromised immune systems:

Do not eat hot dogs, luncheon meats, or deli meats, unless they are reheated until they are steaming hot.
Avoid getting the liquid from hot dog packages onto other foods sources, utensils, and food preparation surfaces, and remember to wash hands after handling hot dogs, luncheon meats, and deli meats.
Do not eat soft cheese products such as feta, Brie, and Camembert, blue-veined cheeses, or Mexican-style cheeses such as queso blanco, queso fresco, and Panela, unless they clearly state they are made from pasteurized milk written on the labelling of the product.
Do not eat chilled pâtés or meat spreads. Canned or shelf-stable pâtés and meat spreads can be eaten.
Do not eat refrigerated smoked seafood, unless it is contained in a cooked dish, such as a casserole. Refrigerated smoked seafood, such as salmon, trout, whitefish, cod, tuna or mackerel, is most often labeled as “nova-style,” “lox,” “kippered,” “smoked,” or “jerky.” The fish is found in the refrigerator section or sold over deli counters of grocery stores and delicatessens and supermarkets. Canned or shelf-stable smoked seafood may be eaten.

A number of people have contacted me in request that I give some information about sterilizing cooking pots and other kitchen utensils. For most of us in the western world it is not absolutely necessary to sterilize pots as long as we make sure that we wash them thoroughly in very hot water and washing up detergent and a scrubbing pad. In other areas of the world or in situations where pots have been out in field conditions for any period of time, especially in areas where disease is prevalent, the need to continually sterilize pots may be a critical factor in the prevention of food contamination and the recontamination of sick people and the promotion of food hygiene in areas where it does not exist.
Firstly we need to look at the different types of cooking pots. The easiest type of kitchen cooking utensil to sterilize is stainless steel because we can clean it chemically without changing its properties. Other forms of pots present more problems. In Africa it is very common to cook in what, in some places, is called a “poike”. If I am not mistaken this is an Afrikaans word for a cast iron cooking pot. It is cast from a thick sheet of iron or steel and is designed to sit over an open fire. They come in many different sizes and are usually very heavy indeed. They have usually been treated with blackening so they have an outer covering. They also have a thick metal carrying handle that is attached to the rim of the pot across its diameter.
Another form of cooking pot is the aluminum pot. the advantages of aluminum are that it is lightweight and heats up very quickly. The disadvantages of aluminum are that it reacts to just about every form of chemical used to sterilize kitchen equipment. Even the acid in tomatoes, lemon and eggplants remove the essential oxidized layer on aluminum pots. The metal is relatively weak and handles usually fall off after a period of use.
Copper is another form of metal use to make cooking pots but utensils made from copper are normally expensive and in my opinion would not be used in areas of the world which require the sterilization of cooking equipment. In any case we can class it as having very similar properties to aluminum from a cleaning perspective.
Probably the oldest and most traditional way to sterilize all forms of cooking equipment is to boil them in boiling water. Adding some salt to the water will help in the disinfecting process and it will slightly increase the boiling temperature of the water and destroy more bacteria. The advantage of this system is that the pots and pans are immediately ready for use after sterilization. The disadvantages are that the equipment has to be 100% clean before going into the sterilization pot and they require a minimum of thirty minutes to boil before it is safe to take them out. Boiling does not ensure that all types of bacteria will be destroyed and some toxins can survive boiling.
Continuing with the theme of using water to sterilize kitchen equipment another efficient way to sterilize pots and pans is with steam. Steam is much hotter than water it will sterilize things that come into contact with it much more quickly. Using steam under pressure also removes baked on fats and other sediments. Steam treatment is OK for all types of metals but Steam is dangerous and requires that special equipment be worn before working with it safely and efficiently. This equipment should include thick plastic apron, thick plastic or neoprene gloves (not surgical gloves) and eye protection goggles. Like with water the advantage of steam is that equipment can be put straight back into use with no further treatment other than washing with a mild detergent and rinsing with water.
Caustic Soda is the next form of sterilization which I would like to talk about. Caustic Soda destroys all forms or organic material. Concentrated caustic soda needs to be diluted with water and heated to a temperature of no more than 80 degrees Celsius. Caustic soda breaks down at temperatures above 80 degrees Celsius and ceases to be effective.
Great care must be taken with caustic soda because it is very dangerous and can cause serious burns and blindness if it gets into your eyes. People using caustic soda should be properly trained and should also wear protective clothing which should include a thick plastic apron, thick neoprene gloves and a full industrial plastic face mask. This chemical is only suitable for stainless steel, plastic and glass. Other forms of metal will be affected by the chemical reaction of the soda. Aluminum may even be eaten away completely.
The use of caustic soda is also good for removing stubborn cooked on foods. The disadvantage of using soda is that it needs to be washed off dishes completely before they can be used again. Most big kitchen will use a high pressure tray washing machine to do this. If your water supply is not infected you may want to consider rinsing the pots in boiling water to avoid re contamination.
Caustic soda melts the fat in your skin if it spills onto the skin and it causes a slimy film on the surface of the skin until it is properly washed off with cold water. Wash until this feeling has completely gone. Caustic soda is also good for cleaning glass, ceramic and plastic utensils.
Yet another method of sterilizing kitchen equipment is to soak it in hot water and chlorine cleaning powder. Chlorine kitchen powder is also good for removing stubborn stains on ceramics, glass and Pyrex. This type of sterilization will react with aluminum and will remove the oxidized lawyer on the surface of the aluminum which is necessary to remove the toxicity of aluminum. Pots may become unusable if exposed to chlorine powder; therefore, I do not advise using chlorine powder to sterilize aluminum
This form of sterilization requires that equipment be soaked for about three to four hours for good results. Similarly to the use of chlorine must be washed off completely with a mild detergent before reusing treated equipment.

Cholera is a disease of the human digestive system and it is passed from person to person through the drinking if infected water or eating food infected with the cholera bacteria. Cholera is caused by the bacterium Vibrio Cholerae which is a comma shaped gram negative bacteria.

Cholera is usually contracted when the feces of an infected person or persons comes into contact with food or a water supply but cholera has been know to exist in non feces infected brackish water. However cholera has also been know to be contracted by eating raw shellfish which can be infected with cholera. Some coastal areas including the Gulf of Mexico, the west African Coast, The east African Coastline, parts of the Brazilian coastline and parts of the South China Sea coastlines are renowned for having cholera infected shellfish. It is suspected that the pumping of raw sewage into the sea is responsible for this phenomenon.

Cholera is very common in areas which have poor treatment of sewage and drinking water. Many cases of cholera infection are very mild but other instances may be very severe. The disease is caused when the bacteria produce cholera toxin which inserts itself into the cell walls of the cells which line the small intestine. It acts as a very efficient chemical water pump which draws vast amounts of water into the lumen of the small intestine.

The bacterial infection which causes cholera is not very dangerous in itself on condition that the symptoms of the disease are well managed. It is the symptoms which present the danger. Persons infected with cholera have been know to be seriously dehydrated within one hour from the onset of diarrhoea, can go into shock within three hours and can die from severe dehydration in the space of twelve hour if they do not receive proper medical attention.

If properly managed the body can wash the disease out in the space of a few days. the main problem with cholera is re infection. If there is no clean water or uncontaminated food to be had the cycle continues. The main impact of cholera is on the elderly, the very young and people who may already be weakened by malnutrition or another disease. The main treatment which is now used to combat this disease is oral re hydration therapy. Re hydration should be started as soon as possible. In very severe cases a drip may be needed in addition to oral re hydration therapy. Medical staff who are used to treating this disease and in using this technique have saved many millions of lives especially in the developing world.

How many times have your workers phoned in to you and said “boss, I got a virus. I can’t get off the toilet”? During the summer months especially it seems as though somebody is taken ill by a virus every week.

I usually asked them to bring me a doctors note and let it at that. Force major, what can you do? It seemed like I was the only one who never got sick. Could it be that responsibility is the best prophylactic medicine around? I always added “come straight in as soon as you feel well. Even though I knew that this was not the best thing to do. Soon you’ll understand why even if this statement confuses you right now.

The doctor usually always tells you the same thing. “yes you’ve caught that virus that’s been going around. Take something to reduce the fever, stay in bed for three days and drink plenty of water”. We all know that a virus is a variety micro organism that has the ability to infect us with several types of very unpleasant types of illness. The most common of these are upper respiratory tract infections and stomach infections. Other viruses which are less common in the western world due to attention to public hygiene issues include pneumonia, viral meningitis, viral pneumonia, hepatitis A, B and C, polio, several forms of zoonotic encephalitis, yellow fever, dengue fever, western Nile fever, rift valley fever, ebola disease, colorado tick fever, machupo, junin, rabies, small pox, various forms of cancer causing viruses and HIV to name but a few. All of these are very serious life threatening illnesses. Some viruses produce conditions which are considered mildly uncomfortable such as mouth ulcers, foot and mouth disease, cow pox and common warts, to mention just a few. There is a whole other range of diseases that are termed as childhood diseases which are also of viral origin. These viral conditions include measels, german measels chicken pox, mumps, and whooping cough. Some of these are included in inoculations against the contraction of dangerous disease during childhood and some are left to the course of nature. Viruses also impact animals and plant species with often serious financial impact. Dog parvo virus is the most resilient of all viruses.

Scientists were divided in their opinion on whether it was correct to classify viruses as living organisms because they have no metabolic function as such. Viruses in simplistic terms are made up of a proteinous outer shell, proteinous genome material, enzymes and sometimes lipopolysaccharide (fatty) outer structures . All viruses are host specific but are not only host specific but are parasitical only to specific organs of the host. Rabies virus travels only along the tissue of the nervous system and will not attack the cells lining the intestine or the blood tissues. The virus that causes the common cold will not cause hepatitis and so on.

The following clip explains the path of avian flue infection. Remember that although viruses all have slightly different ways of getting into and out of living host cells the bottom line is that they all have the same objective and basically do the same thing.

All viruses enter the body via a vector. That vector could be organic material contaminated with feces, it could be via infected water or it could be introduced into a recipient body by body fluids such as saliva or sperm or it can be transferred via mosquitos or ticks. A virus is a really just a mechanism for replicating itself and it does this in the following manner. All viral invaders must breach the cell wall of the host cell and empty the contents of the viral body into the host cell. After doing this the virus activates its genetic material, each in it’s own way, to insert DNA or RNA into the DNA or RNA of the recipient which it then uses as a template to manufacture duplicate strings of DNA. The strings of DNA are then used to transcribe a code for the production of proteins which will be used to manufacture duplicate viruses within the recipient cell.

The recipient cell will cease to function as a useful cell of the body which may or may not stimulate an immunological response by the organism. When the cell wall has swollen to proportions it can no longer tolerate it will burst and the newly manufactured viruses within will flood into the organism and infect more cells. The condition in which the body is swamped with these newly released viruses is known as viremia. During the period in which the virus is initially infecting the body there is usually no immunological response. This is due to the fact that all the process is being carried out within the cell and the immune response of the body is slow to pick up on this in the initial stages because viruses can go undetected by immune cells if they have undergone some form of mutation which makes them apperar differnt to the imunological memory cells.

When the body starts to be flooded with newly developed viruses the immune response will be triggered and the host and symptoms will appear. The period of time between infection and the manifestation of symptoms can be anything between several hours in some cases to several years in the case of some retro viruses such as the HIV virus. Some viruses will insert their DNA into the DNA structure of the host and encode it to remain dormant. All of us have a certain percentage of dormant viral DNA mixed in with our own DNA. This is termed as Junk DNA. Only under very special conditions will this DNA be activate to begin the manufacture of replica viruses.

Viruses that infect the small intestine typically target the epithelial cells which coat the villi. When this happens the affected areas of the intestine will cease to absorb nutrients from the food. The food will remain in liquid form to which the liquid content of the cells is added on rupturing. In addition more liquid from the non specific immune system is added and the food is evacuated as what we recognize as diarrhea. Viral intestinal disorders can be accompanied with vomiting, nausea, headache and increased temperature. All of these symptoms are part of the bodies strategy to clear itself of the viral invader.

The swelling of the cell wall and its bursting under the pressure of the newly developed virus within is known as Lysis. Lysis is the destruction of the cell due to internal causes. During this process ulcerated and painful lesions may be formed in infected tissue. When these burst the viruses are released into the blood stream causing viremia. This destruction of cellular tissue can be accompanies by the presence of blood in stools. Loss of blood in stools is a case for medical supervision because the amount of blood lost may well have to be replaced by blood transfusion.

Viral infections of the intestine can last anything from a day to several weeks and vary in intensity. A long lasting infection may be severe of mild. It all depends on the virus in question and if the bodies defenses have any memory of this virus or viruses with similar protein structures on the outer wall. Some short lived infections can be extremely unpleasant and in contrast they can be very mild. There are no set rules. Viruses change the structure of their cell walls through mutations. This is part of the evolutionary success of viruses. The sheer numbers by which they replicate themselves leaves every statistical possibility for viral mutations to occur.

This video of the production of the HIV Retro Virus is a good animation of how viruses use host cells to transcribe the proteins that they need to reproduce themselves. In oter types of virus the process is simpler but basically the same.

The only sure way to protect yourself against entero viruses is to maintain a good personal hygiene regime in the home and at work and to buy food from a safe reliable source and to make sure that you have a safe water supply..

E. Coli or escherichia coli are gram negative, rod shaped, motile or non motile, non spore producing facultative anaerobic bacteria which live in the lower intestine of all warm blooded animals. E. Coli species that are capable of propulsion do so by means of a ‘flagella’ which is a whip like tail.

Most types of e. coli are absolutely harmless and are part of the normal and necessary flora of warm blooded species. In fact they are very necessary because they produce vitamin K as a bi product of their metabolic activity and by existing in great numbers help by preventing other pathogenic bacteria from colonizing the gut.

Some species of e.coli are pathogenic which means that they can cause desease. The strains that are pathogenic are 0157:H7 and 0111:B4. This particularly virulent capacity was transferred to these e.coli bacteria from shigella bacteria which passed shiga toxin to e.coli by means of bacteriofages which are a type of viral species. Both these strains of e.coli have the capability of transferring their virulent qualities to other bacteria around them by means of their sex pilus which is a needle like protrusion from the side of their body wall by which they insert the DNA codes necessary for the production of virulent qualities into bacteria next to them. One such virulent quality is the ability to resist certain anti biotics.

The very virulent strains of coli such as 0157:H7 and 0111:B4 are capable of causing serious intestinal illness particularly in the very young, old and the immunologically compromised. However it must be stressed that the majority of common e.coli outbreaks are mild and cause only diarrhea and mild temperature increase. More serious virulent cases can cause complications such as hemolytic-uremic syndrome.

E. coli toxins can be heat tolerant or heat labile. This quality makes the boiling of water to kill e. coli unsure and in such a case water should be boiled in a pressure cooker, if available, for at least twenty minutes. Another alternative would be to only drink safe bottled water if possible. E. coli bacteria which escape from the intestine into the abdominal cavity through means of a perforated ulcer, intestinal lesion or a ruptured appendix will cause peritonitis and be life threatening if not treated promptly with antibiotics such as streptomycin and gentamycin to which e.coli are very sensitive. E. Coli which are associated with the intestinal mucosa lawyer can be found in greater numbers in conditions such as Crohns disease, iritable bowel disorder and ulcerative colitis.

E.coli is contracted through contact with contaminated food or water sources in which the content of the gut as come into direct or ‘indirect’ contact with food or water. Severe cases of e. Coli infection can resemble cholera.

New strains of E.coli are continually being produced by the process of mutation. Some strains may develop traits that are harmful to the host animal. E.coli prefers to reproduce at the temperature of 37 degrees Celsius but some strains have shown the capacity to reproduce at temperatures of up to 49 degrees Celsius.

E. coli has been found in agricultural produce such as spinach. In 2006 there was a famous outbreak of contaminated spinachin the US due to the fact that bovine feces polluted a spinach field which was at the bottom of the hill on which a herd of cattle were kept. In this case all the spinach was recalled and destroyed.

E. coli contamination can be prevented for the most part by maintaining a correct food hygiene policy in the kitchen and by using reputable food suppliers.

One of the great pastimes of all time has to be the camping holiday. So many of us work at the same old job day in and day out going through the same old routines time and time again. We long for the day when we can hang up that apron, pack everything we need into a back pack and head out onto the open road. At least some of us do.

Camping holidays vary greatly. To some camping may be sleeping rough next to the camp fire with only the stars for a roof. To others camping may be a luxury safari in Kenya where everything is meticulously planned right down to the champagne on ice and after eight mint on the pillow. Whatever our dream camping holiday may be, we should remember that we are no longer in our natural environment. We can no longer say that we are entirely suited to living out in the open. The days when our distant ancestors were hunter gatherers are long gone and the level of natural immunity that they possessed we can only wish for.

When we are in an outdoor environment for an extended period of time we need to keep in mind that we take care of all of our needs in the same environment whereas in our homes we have created separate environments to cater for our various needs. When we are in the outdoor environment we actually have very limited control over it. The quality of water in a natural environment is what it is. We can do nothing to change it nor can we do much to deter insect vectors such as flies, ants, ticks and leeches, for example.

The only way we can control the effect that the environment has on us is to control the way we organize ourselves within it. The most important logistical problem that we face from a food hygiene aspect is the problem of water. We must have a safe source of water. The second most important problem that we face is having safe food to eat and the third most important problem that we have to contend with is how to take care of our personal hygiene needs without contaminating the area in which we have to live. Ideally these should be three separate areas. This will reduce the risks of cross contamination.

On a camping trip we may have only one source of water which we have to use for purposes of hygiene, cooking and drinking. This presents a challenge which needs to be addressed. Indeed, a great many cases of serious food and water poisoning originate on camping trips. I can vouch for this personally.

The four golden rule of food hygiene apply as much outdoors as they do indoors. Lets take a look at the four rules and see how to apply them successfully in the camp site scenario.

Rule 1. Buy food from a safe source.
In the camp site this means take food that will not perish. Sterilized packs of food can be bought in specialist outdoors shops which are identical to those used by special forces. Failing that take dried foods and foods that have been packed in small tin cans, tubes, concentrates etc. Avoid taking fresh meats and fish at all costs. Even cooked meat will have a very limited life and can only be taken into account as a packed lunch for the first day to be eaten within four hours of setting off. Fruit such as apples can be taken for several days provided they are washed properly, dried and wrapped in a plastic bag in individual portions. Eggs should be avoided also unless you can get them fresh on your trip. Boil them for no less than 10 minutes. Likewise some hard vegetables such as carrots can be taken for the first couple of days. Again it is best to peel them, wash them thoroughly, dry them and wrap them hermetically in a plastic bag. Do not eat local food on trips unless you are absolutely sure that the source is safe. If you are unsure about a water source it is better to drink fresh milk than drink the water. If you catch dysentery you may well loose more water than you can intake.

Rule 2.Prevent bacteria from entering your food.
Again, by having your food closed in hermetically sealed wrapping the possibility of contamination is greatly reduced. Do not open more than you need for each meal. Do not mix food which has been opened with closed food. Do not leave food for long periods unattended. Either eat it or cook it. Preferably cook it. When handling foods make sure that you are clean, particularly hands and nails. Do not use knives that have been used for any other purpose other than for food. Clean them thoroughly before use as well as after use. Likewise, clean your bowls, plates, cups, knives and forks before eating and drinking as well as directly after the meal. Once clean I recommend putting them into a clean plastic bag to avoid contamination while on the trail. Use only clean water for cooking. If you are unsure of the water source and you have no other use a camp carbon filtration system or use chlorine water purification tablets. The water won’t taste great but it will make it drinkable provided there are no chemical contaminates in it.

Rule 3. Prevent the multiplication of bacteria in your food.
As you may have no way of keeping your cold food at a correct cold temperature it is always wise to eat all your food hot. Don’t leave food laying around. If your food source is all but sterile to begin with you won’t have many worries about the multiplication of bacteria in your food. The secret is to open it and eat it or heat it up and eat it as soon as possible. By that I mean within twenty minutes of being cooked. With a bit of correct organization and compromise on five star cuisine one can all but eliminate this stage.

Rule 4. Destroy bacteria on utensils and work surfaces.
Once again prior organization is the order of the day. Always take some washing up liquid and Lysol or dettol hygiene spray or wipes. Wash all work surfaces thoroughly with soap and rinse with water followed by spraying it with Lysol spray or wiping with an anti bacterial wipe. Do this before and after use. As previously stated wash all eating utensils before and after use. After use spray or wipe with an anti bacterial product and wrap in a clean plastic bag. Seal it as hermetically as possible. Discard the plastic bag after opening it for the next use. Old wrapping should be collected in a trash bag and taken home with you.

Keep your dirty clothing as far away as possible from your eating utensils and food. Make a field toilet at least fifty paces away from your camp site. Even if this is a hole in the ground make sure that you cover your excretions with some of the soil or sand that you have dug from the hole. If you have it pour a little chemical sanitizer onto the soil to deter flies. Avoid camping where others have defecated in the open. Scour the area before choosing the location. Do not wash and brush your teeth in the same area that you go to the toilet or eat. Choose a place suitable for this. If you cant wash as well as you would like use hygienic wipes. Particularly use them after washing your hands after visiting the toilet.

Many people like to entertain the notion that one is allowed to be a bit more lax on a camping holiday. This is the pitfall that causes so many people to fall terribly ill when camping. Nothing could be further from the truth. A healthy and successful camping trip requires quite a high level of forethought, prior organization and planning and an appropriate level of self discipline without ruining the holiday by being overly fanatical and obsessive. This is not what I am advocating. If performed systematically all of my suggestions should take no more than a few minutes of your time around mealtimes and safeguard you against several unpleasant days in hospital and a lifetime’s bad memory.

Most of us in the western world think of dysentery or “Shigella” as a disease of the summer months. Have you ever thought why? Firstly, is it true? Is dysentery a disease of the summer months?

Ok, now I’m going to confuse you a little more because the answer is yes and no. No because dysentery is not only a disease of the summer months and yes because it is mostly proliferated throughout the western world during the summer months, but why?

Dysentery is a disease that is spread via contaminated food and water. A lot of our summer produce is picked in warmer regions of the world where the water sourses osed to irrigate and to wash produce before packing may not be of the best quality and may contain many contaminants. In addition, workers who pick and pack produce may be carriers of certain types of dysentery causing bacteria.

Another major cause of dysentery during summer months for westerner’s is travelling to warmer climates. Whereas locals in many areas of the world may have developed immunities to many bacterial and protozoic species, all of these may be new for us. By being tempted to eat as the locals do we are often exposing ourselves to sources of food and water contamination.

Dysentery is caused by several major causes lets have a look at a couple of them.

Bacterial Dysentery. Bacterial dysentery is caused primarily by the bacterium Shigella dysenteriae. The disease it causes is called shigellosis. This bacterium is a gram negative, non motile, rod shaped, non spore forming facultative anaerobic species that produces a toxin called shiga toxin which is what causes the reaction which we know as dysentery.

Allow me to translate that mouthful of scientific jargon for you. Firstly Gram testing is a form of bacterial staining devised by a man called Mr. Gram which adheres to proteinous outer shells but not to fatty shells. As the vast majority of gram negative bacteria have a Lipopolysaccharide outer shell the dye will not stick, therefore the bacteria are classified as gram negative. Non motile means that they have no mechanism by which they can propel themselves within the medium they are in. Non spore forming means that the bacterium does not have the capability of reducing it’s structural size to permit it to survive periods when conditions are not suitable for bacterial growth, hibernating in short. Facultative anaerobic means that it can live in an oxygen rich environment or in one which is void of oxygen. It is usually when in the anaerobic phase that facultative bacteria will produce their toxins.

The symptoms of dysentery are high fever, vomiting, diarrhea, severe dehydration. Shega toxin is a potentially deadly toxin. Patients with dysentery may experience projectile diarrhoea and projectile vomiting simmultaneously. This is a very unpleasant condition which I have experienced personally. With this disease fluid intake is vital even if that means via infusion and a strict hygiene regeme is vital to rule out the possibility of re infection. Recovery usually takes anything between one to two weeks but in many areas of the world high mortality is common due to improper conditions with which to treat this condition. Mortality rate is particularly high in children and the elderly.

Amoebic Dysentery. This form of dysentery is also spread by the ingestion of contaminated food and water. It is caused by a cyst forming amoebic species. The disease is called intestinal amoebiasis.

This disease is most common in the developing world but not only. One case was reported in St. Petersburg which is quite close to the artic circle. Both bacterial and Ameobic Dysentery are prevelant in developing countries and often get confused. Most cases of travellers dysentary are in fact bacterial or viral in origin. Amoebic dysentery is a parasitical disorder and will not be effected by antibiotics. This form of dysentery may cause infection and enlargening of the liver and blood in stools. Other symptoms remain very much the same as in bacterial dysentery. Metronidazole is the preferred treatment for Amoebic Dysentaty.

Note. Not all species of amoebae are cyst forming.

Zoonotic diseases are ones which are passed from the animal kingdom to human beings. Many micro organisms tend to be species specific and it is for this reason that there are not a great many zoonotic diseases. Some diseases passed on to us via animals are very common whereas some others are very rare. Some have the potential to cause world catastrophes whereas others may just about give us an upset stomach.
Below you will find a list of zoonotic diseases in alphabetical order.

Anthrax is a serious disease that is found in all warm blooded animals. The specific host is thought to be antelope and carnivores seem to react more slowly to the bacteria. The bacteria responsible for the cause of anthrax is Bacillus Anthracis. Human infections usually occur through the skin but it may also be inhaled or ingested. This is a very resistant spore forming bacteria whose spores may survive for decades in soil or animal products. The distribution is worldwide. Gastrointestinal anthrax is a very uncommon, often-fatal manifestation of the disease, caused by devouring meat from an animal that died of the disease. Gastrointestinal anthrax causes inflammation of the stomach and the intestine accompanied by sores or ulcers, much the same as the lesions that appear on the skin in the skin form of anthrax. The primary signs of the disease include nausea, vomiting, loss of appetite and fever, followed by severe abdominal pain, vomiting of blood, and severe and bloody diarrhea.

Brucellosis comes in four strains, B. abortus (in cattle), B. melitensis (sheep or goats), B. suis (pigs), and canis (dogs). The distribution of brucellosis is distributed worldwide. The disease id contracted via direct contact with animal excretions including milk. it is a disease caused by any of several forms of the gram-negative coccobacilli Brucella: Brucella melitensis, B. abortus, B. suis, and B. canis, the latter of which is very rare and causes only mild illness. Brucellosis is most common in rural areas among farming populations, vets, meat packers, slaughterhouse staff, and livestock breeders. Laboratory workers are also among those who are at risk. It is primarily a disease of animals (including cattle, pigs, sheep, camels, goats, and dogs); humans usually contract it through ingestion of contaminated and unpasteurized milk or other non cooked milk products or by ingesting raw meat or bone marrow, through skin lesions and cuts, through direct contact with an infected animal, or through the inhalation of dust particles that may be present in contaminated soil. Symptoms of brucellosis are manifested as follows: fever, chills, sweating, malaise, and weakness. The fever often occurs in recurring waves, rising in the evening and subsiding during the day, separated by periods of remission at intervals. Other symptoms may include weight loss, headache, muscle and joint pain, and an enlarged spleen, and often orchiepididymitis in young men. In some victims the disease is acute; however, more often it is chronic, recurring over a period of months or years. Although brucellosis itself is rarely fatal, treatment is important because serious complications such as pneumonia, endocarditis, meningitis, and encephalitis may develop. Tetracycline plus streptomycin is the preferred treatment for this disease; bed rest is also of great importance. A vaccine is available outside the United States. The disease can also be called Cyprus fever, dust fever, Gibraltar fever, Malta fever, Mediterranean fever and undulant fever. See also abortus fever.

Campylobacteriosis is caused by the bacterium campylobacter spp. It is carried by many animal species with a seemingly increasing incidence rate. Most species of animals seem to be reasonably host specific but cross infection is possible usually via fecal contamination of food. Improper or incomplete cooking of food is the most common way that the disease is spread, and it is commonly thought by bacteriologists that poultry account for over half the diagnosed cases. Untreated water and raw milk are also potential sources of contamination.
The incubation period after exposure is from one to ten days. symptoms begin with a day or two of mild fever, muscle aches, and headaches. This stage is followed by symptoms that involve the the intestinal tract. Diarrhea occurs with or without the presence of blood and severe abdominal cramps are the overriding intestinal symptom. The severity of symptoms may vary from case to case, ranging from only mild fever to severe dehydration and very rarely death (this is seen mainly in the very young or old). The disease usually lasts for about a week, but persists longer in about twenty percent of cases. At least ten percent will have a relapse, and some patients will continue to pass the bacteria for several weeks after recovery.
Complications

Clostridial disease is caused by the bacterium clostridium spp. It is transferred by mammals, birds and fish with a worldwide distribution. Although the disease is normally transmitted through wound infection, food poisoning does occur. There is little danger of cross species transmission. The clostridial family of bacteria are noted by their ability to manufacture very potent toxins. The most potent toxin in nature is produced by the bacterium Clostridium botulinum. This toxin renders the bodies ability to contract muscles ineffective and death will occur by paralysis and asphyxiation, or the inability to inhale. Clostridium botulinum is found in the manure of animals along with clostridium tetani, clostridium difficile and clostridium perfringens, which causes gas gangrene. These bacteria are spore forming and the spores can survive for many years in soil. When conditions are favorable the bacterial spores will grow back into bacteria and begin to produce toxin.

Food that has been improperly preserved or stored can harbor botulinum toxin-producing clostridia. Botulism symptoms usually appear within 18-36 hours after eating contaminated food, in extreme cases it may take four hours to eight days for the bacteria to develop toxin. Initial signs of infection include blurred or double vision and difficulty in swallowing food and speaking. Gastrointestinal problems may include constipation, nausea, and vomiting. As botulism progresses, the victim experiences weakness or paralysis, starting with the head muscles and progressing down the body. Breathing eventually becomes increasingly more and more difficult. and without medical intervention, respiratory failure and death are the likely outcome.

Listeriosis is caused by the bacterium listeria monocytogenes and it can be found in numerous species of animals and birds. It has a worldwide distribution. Listeriosis was traditionally considered to be a disease of animals for the most part. However in recent decades there has been an alarming increase in the incidence of this disease. The symptoms can be severe and patients who are high risk may have a problem overcoming listeriosis. It is becoming resistant to many forms of antibiotics. This is primarily a food borne bacteria. Listeria can be contracted by the ingestion of contaminated meat, dairy products, shellfish, dust and by coming into contact with infected animals. Listeria can pass through the wall of the gut and enter the bloodstream. It likes to sit on the central nervous system and spinal column. Pregnant mothers can spread this disease to their unborn babies through the placenta. Listeria cam cause severe flu like symptoms, meningitis and encephalitis. Listeria is also found in soil, sewage and in five percent of the intestines of humans without them feeling any ill effect.

Salmonellosis is transmitted by the salmonella spp. Bacteria which has over two thousand serotypes. It can be found in all animal species but it is not commonly thought to infect fish. The distribution of salmonellosis is worldwide and the occurrence of this disease is mostly attributed to the ingestion of undercooked food which is contaminated with feces. It is a form of gastroenteritis that is usually caused by the ingestion of food that has been contaminated with a species of Salmonella bacillus. It is characterized by an incubation period of six hours to forty eight hours which is followed by sudden colicky abdominal pain, high fever, and bloody, watery diarrhea. Nausea and vomiting are common symptoms, and abdominal signs may be almost identical those of acute appendicitis or cholecystitis.

Symptoms usually last from four to seven days, but diarrhea and fever may persist for up to 2 weeks. Dehydration may occur. There is no specific treatment for salmonellosis. Antibiotics are usually not prescribed unless the disease has spread beyond the intestine and into other organs. Adequate cooking, good refrigeration, and attention to personal hygiene, especially the washing of hands may reduce the frequency of salmonella outbreaks. Salmonella can also cause typhoid fever.

Tuberculosis is caused by the bacterium mycobacterium bovis (cattle). It can be transferred to humans via cattle and non human primates. The distribution of tuberculosis is worldwide and has now been linked to the aids virus. The disease can be transmitted by any animal species including humans. It now normally takes treatment with three forms of antibiotics simultaneously to combat this bacteria. No other disease throughout history has claimed so many lives. The tuberculosis bacteria will infect the organ via which it entered the body. In most cases this is the lungs. As it has a protective enveloping it manages to outsmart the bodies specific immune system. The tuberculosis bacteria can survive within the non specific white blood cells and by colonising them it can move around the body from organ to organ. This is a slow process. It can transpire over a period of years. In the early part of the last century one in seven people were infected with tuberculosis. In the western world this number has dropped greatly due to the improvement in living conditions and lifestyle. In the third world, particularly Africa , conditions are still right for tuberculosis infection.

Tularemia is transmitted by the Francisella Bacteria. It is transmitted to humans by rabbits, dogs, cats, rodents, sheep and deer. Its distribution is circumpolar within the confines of the northern hemisphere. The disease is transmitted through ingestion when exposed to infected animals and also via bites of arthropods. It is an infectious disease of animals caused by the bacillus Francisella (Pasteurella) tularensis, which may be transmitted by insect vectors or direct contact. It is characterized in humans by fever, headache, and an ulcerated skin lesion with localized lymph node enlargement or by eye infection, GI ulcerations, or pneumonia, depending on the site of entry and the response of the host. This disease can be fatal if not treated with the appropriate antibiotics. Treatment includes streptomycin, chloramphenicol, and tetracycline. Recovery produces lifelong immunity. A vaccine was used in the past to protect laboratory workers but is not currently available; however, a new vaccine is in development. Also called deerfly fever, rabbit fever. Also spelled tularaemia.

Vibriosis is transmitted by the Vibrio parahaemolyticus or the V. alginolyticus bacteria. It is transmitted salt water fish and shellfish and is found primarily in the pacific regions including Asia, Australia, North America and the gulf of Mexico . The cause is the ingestion of undercooked contaminated food. Vibriosis is caused by eating seafood contaminated with Vibrio parahaemolyticus or Vibrio vulnificus. These bacteria damage the inner wall of the intestine, which causes diarrhea and related symptoms. Vibrio vulnificus can get through the intestinal wall and into the bloodstream.
Persons at risk for severe, often fatal vibriosis include those with liver disease (cirrhosis), excess iron (hemochromatosis), thalassemia (a blood disorder), AIDS, diabetes, or those who are immunosuppressed.
Symptoms of intestinal infection occur within two days of eating contaminated seafood. Symptoms last for two to 10 days and include watery diarrhea, abdominal cramps, nausea, vomiting, headache, and possibly fever. Symptoms of a blood infection develop one to two days after eating contaminated seafood, and include fever, chills, low blood pressure, and large fluid-filled blisters on the arms or legs. Similar blisters can also be produced by a Vibrio vulnificus skin infection. This can occur when the skin is pierced by the spines of infected fish. These infections can be severe and sometimes require amputations if not treated in time.

Yersiniosis is caused by the yersinia paratuberculosis or the V enterocolitica bacteria and is passed onto human beings by Animals and birds. It is distributed in the northern hemisphere and is transmitted via contaminated food and water.

Yersinia p. causes septicemia (blood poisoning) often with signs of gastroenteritis which is caused by Yersinia pseudotuberculosis, this occurs in wild rodents, birds, and most domestic species, particularly cats, although this is not common. The symptoms are: high fever, severe toxemia with a high fatality rate. At postmortem there are large numbers of embolic abscesses in most of the internal organs. It is also called pseudotuberculosis because of the way it infects multiple organs.
Occurs also in many species of fish as a septicemia. This form of infection is caused by Yersinia ruckeri.

Zoonoses That Pass To Humans Via Food