ASSIGNMENT # 1FOOD SCIENCES FOOD SAFETY AND HEALTHTOPIC:Introduction to food and water microbiology And Nature of Micro-organisms and parasite.

ASSIGNED BY:Ms.RABIA

ASSIGNED TO:AMNA ADIL

MAJOR:FOOD SCIENCES

MICROORGANISMSA microorganism or microbe is an organism that is microscopic (usually too small to be seen by the naked human eye). Most microorganisms are unicellular (singlecelled), but this is not universal, since some multicellular organisms are microscopic, while some unicellular protists and bacteria, like Thiomargarita namibiensis, are macroscopic and visible to the naked eye. Microorganisms are very diverse; they include: Bacteria: Bacteria are unicellular microorganisms abundant in air, soil, water, and/or organic matter (i.e; the bodies of plants and animals). They can exist either as independent (free-living) organisms or as parasites (dependent upon another organism for life). Size: Typically a few micrometers in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals. Bacteria are smaller than other cells, but larger than viruses. Bacteria are measured in units of length called micrometers, or microns. One millimeter is equal to 1,000 microns; it takes about 25,000 microns to make up one inch (2.5 centimeters). Some bacteria measure only one half a micron. Structure:

Shapes: Bacteria occur in three main shapes: Spherical: Spherical bacteria are called cocci (singular coccus). The cells may occur in pairs (diplococci), in groups of four (tetracocci), in bunches (staphylococci), in a bead-like chain(streptococci)or in a cubical arrangement of eight or, more (sarcinae). Rod-like: Rod-like bacteria are called bacilli (singular bacillus). They generally occur singly, but may occasionally be found in pairs (diplo bacilli) or chains (streptobacilli). Spiral: Spiral-shaped bacilli are called spirilla (singular, spirillum). Short incomplete spirals are called vibrios or comma bacteria.

Bacterial division: Bacteria replicate by binary fission, a process by which one bacterium splits into two. Therefore, bacteria increase their numbers by geometric progression. Geometric progression refers to the population of bacteria doubling every generation time as a result of dividing by binary fission.

Bacterial growth phase:

Lag phase (short) period of adjustment to environment. Exponential or logarithmic growth phase growth begins and accelerates to a phase of rapid, constant exponential growth. Stationary phase depletion of nutrients and accumulation of toxic metabolic products growth is slowed to a point where cell division and cell death are in balance. Death phase population decrease due to death of cells. Viruses: A virus (from the Latin virus meaning toxin or poison) is a small infectious agent that can replicate only inside the cells of other organisms. Viruses are too small to be seen directly with a light microscope.

Size: Viruses are microscopic; they range in size from about 20 to 400 nanometres in diameter (1 nanometer = 10-9 meters). Structure:

Virus levels required for infection and detection: Infection 10 - 100 particles/ml. Detection 10^5 10^6 particles/ml (by electron microscopy). 10^4 10 g particles/ml (by radioimmunoassay). Parasite: A parasite is an organism that grows, feeds and is sheltered on/or in a different organism while contributing nothing to the survival of its host. Fungi (fungi include yeast and moulds): Fungi are microscopic plant organisms that consist of cells, such as mould, mildews and yeast. They cannot produce their own food; thus they behave as either parasites or saprophytes, absorbing nutrients from organic matter, such as humans and animals. More commonly known as moulds and yeasts, fungi are found in nature, and they appear in the environment (Geophilic), on humans (Anthropophlic), and on animals (Zoophilic). Fungi can be recognized by the following five characteristics: The cells of fungi contain nuclei with chromosomes (like plants and animals, but unlike bacteria). Fungi cannot photosynthesize (they are heterotrophic, like animals). Fungi absorb their food (they are osmotrophic).

They mostly develop very diffuse bodies made up of a spreading network of very narrow, tubular, branching filaments called hyphae. These filaments exude enzymes, and absorb food, at their growing tips. Although these filaments are very narrow, they are collectively very long, and can explore and exploit food substrates very efficiently. They usually reproduce by means of spores, which develop on, and are released by, a range of unique structures (such as mushrooms, cup fungi, and many other kinds of microscopically small fruiting bodies). Moulds: Moulds have singular hyphae (a threadlike part of the vegetative portion of a fungus) and produce velvety cotton-looking colonies. Yeasts: Yeasts consist of a single cell and they reproduce by budding, producing soft pasty-looking colonies. Nature of bacteria, moulds, viruses nad parasites: Food borne diseases are caused by bacteria, moulds, viruses and parasites. Certain microorganisms are of greater significance than others for humans. Bacteria and moulds multiply on foods and may produce toxins. Understanding the factors controlling growth of microorganisms allows us to control them in food. Bacteria may be harmful or useful. Bacteria, yeasts and moulds can be used to preserve food. Latic acid bacteria secrete lactic and other organic acids. Organic acids prohibit pathogens in food and in the gut. Viruses and parasites do not grow in food. Micro-organisms classified by their significance: Pathogenic organisms Spoilage organisms Useful organisms. Dangerous micro-organisms and parasites (pathogenic): Bacteria Moulds Viruses Parasites Major bacteria causing food borne diseases:

Aeromonas spp. It is a gram-negative, facultative anaerobic rod that morphologically resembles members of the family Enterobacteriaceae. Fourteen species of Aeromonas have been described, most of which have been associated with human diseases. The most important pathogens are A. hydrophila, A. caviae, and A. veronii biovar sobria. The organisms are ubiquitous in fresh and brackish water. Incubation period: 1 and 7 days - commonly between 24 and 48 hours. Diseases caused by aeromonas spp: Gastroenteritis ranging from mild enteritis to cholera-like diarrhoea. Aeromonas species have also been reported to cause infections such as septicaemia, endocarditis, osteomyelitis, myonecrosis, haemolytic uraemic syndrome, meningitis, peritonitis, respiratory tract disease and ocular infections. In addition to humans, they are also important pathogens in amphibians, reptiles and fish, causing major problems in fish farming. Symptoms: Diarrhea, abdominal cramps, occasional vomiting, mild fever, occasionally people with Aeromonas have no symptoms at all.

Bacillus cereus. Bacillus cereus is an endemic, soil-dwelling, Gram-positive, rod-shaped, beta hemolytic bacterium. Some strains are harmful to humans and cause food borne illness. Incubation period: 1 to 6 hours. 8 to 16 hours 15 hours. Diseases caused by bacillus cereus: There are two illness associated with B. cereus, emetic and diarrheal illness. The emetic illness is caused by the ingestion of a heat-

stable toxin produced by the microorganisms in the food. The diarrheal illness is caused by the ingestion of moderate to high number of B. cereus and their subsequent production of toxin in the stomach. Symptoms: The emetic type of food poisoning, with symptoms similar to that caused by Staphylococcus aureus, is characterized by nausea and vomiting. The symptoms of B. cereus diarrheal illness, similar to Clostridium perfringens food poisoning, include watery diarrhea, abdominal cramps, and pain. Nausea may sometimes occur, and vomiting rarely occurs. Other Bacillus species will cause vomiting and diarrhea.

Brucella spp. Brucella is a genus of Gram-negative bacteria. They are small (0.5 to 0.7 by 0.6 to 1.5 m), non-motile, non-encapsulated coccobacilli, which function as facultative intracellular parasites. Incubation period: Highly variable; 5- 60 days; occasionally several months. Diseases caused by brucella spp: Brucellosis, also called undulant fever, or Malta fever, in humans is a highly contagious zoonosis (infectious disease transmitted from animals to humans) caused by bacteria of the genus Brucella. Brucellosis is a typical zoonotic disease and it spreads from animal to man but it does not spread from man to man. Fever, chills, sweating, malaise, weakness and various types of pains occur in man.Acute brucellosis causes intermittent or undulations of temperatures. So this fever is also known as undulant fever. But these types of symptoms do not occur in all the brucella infections and can be seen only in some.

Symptoms: Ultimately, brucellosis can affect almost any part of your body, including your reproductive system, liver, heart and central nervous system. Some other possible symptoms include headache, weakness, sweating, chills, arthralgia (pain in the joints), depression, weight loss and generalized aching.

Campylobacter jejuni. Campylobacter jejuni is a species of curved, rod-shaped, non-spore forming, Gramnegative microaerophilic, bacteria commonly found in animal feces. It is one of the most common causes of human gastroenteritis in the world. Incubation period: 2 - 5 days (2 10 days) Disease they cause: Campylobacteriosis is the name of the illness caused by C. jejuni. It is also often known as campylobacter enteritis or gastroenteritis. Symptoms: Fever, nausea, abdominal cramps, nausea, vomiting. and diarrhoea (sometimes bloody).

Clostridium botulinum Clostridium botulinum is a Gram-positive, rod shaped bacterium that produces the neurotoxin botulin, which causes flaccid muscular paralysis seen in botulism, and is also the main paralytic agent in botox. It is an anaerobic spore-former, which produces oval, sub terminal endospores and is commonly found in soil. Incubation period: 12-36 hours (months)

Disease they cause: Botulism is a rare but serious paralytic illness caused by a nerve toxin that is produced by the bacterium Clostridium botulinum. There are three main kinds of botulism: y y y Foodborne botulism is caused by eating foods that contain the botulism toxin. Wound botulism is caused by toxin produced from a wound infected with Clostridium botulinum. Infant botulism is caused by consuming the spores of the botulinum bacteria, which then grow in the intestines and release toxin. All forms of botulism can be fatal and are considered medical emergencies. Foodborne botulism can be especially dangerous because many people can be poisoned by eating a contaminated food. Symptoms: The classic symptoms of botulism include double vision, blurred vision, drooping eyelids, slurred speech, difficulty swallowing, dry mouth, and muscle weakness. Infants with botulism appear lethargic, feed poorly, are constipated, and have a weak cry and poor muscle tone. These are all symptoms of the muscle paralysis

Clostridium perfringens Clostridium perfringens (formerly known as "C. welchii") is a Gram-positive, rodshaped, anaerobic, spore-forming bacterium of the genus Clostridium.[1] C. perfringens is ubiquitous in nature and can be found as a normal component of decaying vegetation, marine sediment, the intestinal tract of humans and other vertebrates, insects, and soil. Incubation period: 8 - 24 hours (12 24 hours).

Diseases caused by C. perfringens:Perfringens food poisoning is the term used to describe the common foodborne illness caused byC. perfringens. A more serious but rare illness is also caused by ingesting food contaminated with Type C strains. The latter illness is known as enteritis necroticans or pig-bel disease. Symptoms: The common form of perfringens poisoning is characterized by intense abdominal cramps and diarrhea which begin 8-22 hours after consumption of foods containing large numbers of those C. perfringens bacteria capable of producing the food poisoning toxin. The illness is usually over within 24 hours but less severe symptoms may persist in some individuals for 1 or 2 weeks. A few deaths have been reported as a result of dehydration and other complications.

Escherichia coli Escherichia coli is a Gram negative rod-shaped bacterium that is commonly found in the lower intestine of warm-blooded organisms . Most E. coli strains are harmless, but some, can cause serious food poisoning in humans. Incubation period: 12 60 hours (2 9 days). Disease caused by E.coli: Escherichia coli is one of the most frequent causes of many common bacterial infections, including cholecystitis, bacteremia, cholangitis, urinary tract infection (UTI), and traveler's diarrhea, and other clinical infections such as neonatal meningitis and pneumonia Symptoms: Watery bloody diarrhea, fever, dysentery, sometimes cramps, vomiting.

Listeria monocytogens Listeria monocytogenes is a Gram-positive rod-shaped bacterium. It is the agent of listeriosis, a serious infection caused by eating food contaminated with the bacteria. ncubation period: 3 70 days. Diseases caused by listeria monocytogens: Listeriosis can manifest itself as sepsis, meningitis, encephalitis, intrauterine infections and spontaneous abortions in pregnant women. Meningeoncephalitis; septicemia or meningitis in newborns. Symptoms: Symptoms include fever and chills, headache, upset stomach and vomiting.

Mycobacterium bovis

Mycobacterium bovis is a slow-growing (16 to 20 hour generation time), aerobic bacterium and the causative agent of tuberculosis in cattle. Incubation period: 2-6 months. Diseases caused by mycobacterium bovis: M. bovis is a germ that primarily causes tuberculosis in cattle, but it may also infect and cause illness among other animals, including humans. In humans, M. bovis can cause a type of tuberculosis that may affect the lungs, lymph nodes, and other parts of the body. Symptoms: General symptoms of M. bovis tuberculosis may include fever, night sweats, and weight loss. Other symptoms may manifest themselves depending on the part of the body affected by the disease: disease in the lungs may be associated with a cough; lymph node disease may cause swelling in the neck; and gastrointestinal disease may cause abdominal pain and swelling, and diarrhea.

Salmonella Salmonella is a genus of rod-shaped, Gram-negative, non-spore forming, predominantly motile enterobacteria with diameters around 0.7 to 1.5 m, lengths from 2 to 5 m, and flagella which project in all directions Incubation period: 12-36 hours (2- 7 days) Diseases caused by salmonella spp: Members of the Salmonella genus cause a variety of diseases such as enteric fever, gastroenteritis, and septicemia. Reactive arthritis involving swelling, pain and inflammation of the joints, is a complication following salmonella enteritidis. Salmonella has also been implicated in cases of osteomyelitis in children with co-existant sickle cell anemia.

Symptoms: Headache, fever, abdominal cramps, diarrhea, dehydration, vomiting and nausea.

Shigella Shigella is a genus of Gram-negative, non-spore forming rod-shaped bacteria closely related to Escherichia coli and Salmonella. Incubation period: 12 48 hours (4 - 7 days) Diseases caused by shigella: Shigellosis is an infectious disease caused by Shigella species of bacteria. The disease is characterized by diarrhea, fever and abdominal cramps. Typically the stools may contain blood and mucus, and is called Shigella induced dysentery. Symptoms: Diarrhea, fever, nausea; sometimes vomiting, cramps.

Staphylococcus aureus Staphylococcus aureus is a gram positive bacterium that usually appears under the microscope as spherical (coccus) organisms appearing in pairs, short chains, or bunched, grape-like clusters. Incubation period: 0.5 8 hours (6 48 hours).

Diseases caused by staphylococcus aureus: Staphylococcus aureus has been implicated as a causative agent in acute food poisoning episodes, toxic shock syndrome, impetigo, scalded skin syndrome, cellulitis, folliculitis and furuncles. It is also a common cause of systemic infections such as infective endocarditis, osteomyelitis, epiglottitis, and sinus infections amongst others. S. aureus is also responsible for many infective and systemic infections in the health care setting (nosocomial infections). Symptoms: Nausea, vomiting, diarrhea and abdominal cramps.

Vibrio cholerae Vibrio cholerae (also Kommabacillus) is a gram negative comma shaped bacterium with a polar flagellum that causes cholera in humans .V. Cholerae and other species of the genus Vibrio belong to the gamma subdivision of the Proteobacteria. Incubation period: 2 3 days (hours to days) Diseases caused by vibrio cholera: Cholera is an acute, diarrheal illness caused by infection of the intestine with the bacterium Vibrio cholerae. The infection is often mild or without symptoms, but sometimes it can be severe. Approximately one in 20 infected persons has severe disease characterized by profuse. In these persons,. Without treatment, death can occur within hours. Symptoms: Profuse watery diarrhea, vomiting, and leg cramps; sometimes vomiting; rapid loss of body fluids leads to dehydration and shock; often fatal if untreated.

Vibrio parahaemolyticus Vibrio parahaemolyticus is a curved, rod-shaped, Gram-negative bacterium found in brackish saltwater, which, when ingested, causes gastrointestinal illness in humans. V. parahaemolyticus is oxidase positive, facultatively aerobic, and does not form spores. Like other members of the genus Vibrio, this species is motile, with a single, polar flagellum. Incubation period: 12 - 24 hours (4 7 days) Diseases caused by:Vibrio parahaemolyticus is an intestinal infection that is characterized by lower gastrointestinal distress such as diarrhea and cramps. In some cases, nausea, vomiting, fever and headache may also be present. Occasionally, this disease may manifest itself as a dysentery-like illness with bloody or mucoid stools, high fever and a high white blood cell count, but normally the disease has a duration of only two to three days. Illness with Vibrio parahaemolyticus is most common during the summer months. Symptoms: Nausea, vomiting, abdominal cramps, diarrhea, fever, headache.

Vibrio vulnificus Vibrio vulnificus is a spcies of Gram-negative, motile, curved, rod-shaped bacteria in the genus Vibrio. Present in marine environments such as estuaries, brackish ponds, or coastal areas. Infection with V. vulnificus leads to rapidly expanding cellulitis or septicemia.

Incubation period: 12 - 72 hours Diseases caused:Vibrio vulnificus is mainly implicated in gastrointestinal illness characterized by vomiting, diarrhea and abdominal pain. Vibrio vulnificus can also cause an infection or ulceration of the skin when open wounds are exposed to seawater Symptoms: Chills, fever, prostration, often death.

Yersinia enterocolitica:

Yersinia enterocolitica is a species of gram-negative coccobacillus-shaped bacterium, belonging to the family Enterobacteriaceae. Primarily a zoonotic disease (cattle, deer, pigs, and birds), animals that recover frequently become asymptomatic carriers of the disease

Incubation period: 3 to 7 days. (2 3 weeks) Diseases caused:Yersinia causes an acute bacterial enteric disease that causes diarrhea and/ or vomiting. The bacteria may also cause infections of other sites such as wounds, joints and the urinary tract Symptoms: Diarrhea, abdominal pains, mimicking appendicitis, fever.

Some toxigenic moulds causing food borne diseases: Aspergillus spp: Aspergillus is a genus of a few hundred molds found throughout much of nature worldwide. Incubation period:Incubation period from few days to weeks Diseases they cause:Some Aspergillus species cause serious disease in humans and animals. Aspergillus spp. cause disease on many grain crops, especially maize, and synthesize mycotoxinsincluding aflatoxin. Symptoms: fever, cough, chest pain or breathlessness.

Fusarium spp:Fusarium is a large genus of filamentous fungi widely distributed in soil and in association with plants. Most species are harmless saprobes and are relatively abundant members of the soil microbial community. Some species produce mycotoxins in cereal crops that can affect human and animal health if they enter the food chain. Incubation period: Unknown. Diseases they cause: : Fusarium spp. are frequently involved with eye, skin, and nail infections. More severely it can produce hemorrhagic syndrome (alimentary toxic aleukia) in humans. Several species can produce the trichothecene toxins which target the circulatory, alimentary, skin, and nervous systems. Vomitoxin is one such tricothecene mycotoxin that has been associated with outbreaks of acute gastrointestinal illness in humans. Zearalenone is another mycotoxin produced by Fusarium. It is similar in structure to the female sex hormone estrogen and targets the reproductive organs.

Symptoms: Nausea, vomiting, diarrhea, dermatitis, and extensive internal

bleeding.

Penicillium spp:Penicillium is a genus of ascomycetous fungi of major importance in the environment, food and drug production. It produces penicillin, a molecule that is used as an antibiotic, which kills or stops the growth of certain kinds of bacteria inside the body. Incubation period: Unknown. Diseases the cause: Type I allergies (hay fever, asthma). Type III hypersensitivity pneumonitis: Cheese washer's lung, Woodman's lung, Moldy wall hypersensitivity. Symptoms: Respiratoy symptoms, skin rash, shortness of breath, itchy throat, conjunctivitis, red-rimmed eyes, crusted eyelids, chronic sinusitis. Main sources: Fruits, nuts, grains and products made from grains.

Major viruses causing foodborne disease: Hepatitis-A virus: Incubation period: varies from 10 to 50 days (2 6 weeks). Diseases it cause: Hepatitis-A ( hepatits-A refers to liver inflammation).

Symptoms: Tiredness,Loss of appetite,Fever, Nausea, Abdominal pain or discomfort, Jaundice (yellowing of the eyes and skin), Darker colored urine, Light or chalky colored stools, Rash, Itching, Muscle pain.

Hepatitis-E virus:Incubation period: 3 to 8 weeks. Diseases it cause: Hepatitis E. Symptoms: Jaundice (yellow discoloration of the skin and sclera of the eyes, dark urine and pale stools), anorexia (loss of appetite), an enlarged, tender liver (hepatomegaly), abdominal pain and tenderness, nausea and vomiting, and fever.

Small round structured viruses (SRSV):Incubation period: 24-72 hours. Diseases it cause: Illness caused by SRSV infection has several names, including: Stomach fluthis "stomach flu" is not related to the flu (or influenza), which is a respiratory illness caused by influenza virus. Viral gastroenteritisthe most common name for illness caused by SRSV. Gastroenteritis refers to an inflammation of the stomach and intestines. Acute gastroenteritis. Non-bacterial gastroenteritis. Food poisoning (although there are other causes of food poisoning) Calicivirus infection. Symptoms: Diarrhea; stomach pain and vomiting for 24 to 48 hours. An infected person may also suffer from abdominal pain, headache and a low grade fever.

Rotavirus:Incubation period: 1-3 days. Diseases it cause: Severe diarrhea among infants and young children, and cause infections commonly known as stomach flu, despite having no relation to influenza. Symptoms: Vomiting, watery diarrhea, and low-grade fever.

Polio virus: Incubation period: 5 - 35 days. Diseases it cause: Poliomyelitis, often called polio or infantile paralysis. Polio is a viral disease which may affect the spinal cord causing muscle weakness and paralysis. Symptoms: Up to 95 percent of people infected with polio have no symptoms. However, infected persons without symptoms can still spread the virus and cause others to develop polio. About four to five percent of infected people have minor symptoms such as fever, muscle weakness, headache, nausea and vomiting. One to two percent of infected persons develop severe muscle pain and stiffness in the neck and back. Less than one percent of polio cases result in paralysis.

The human intestineThe source and target of foodborne viruses: y Viruses that cause diarrhoea: Name. Small round structured viruses (SRSV)

Microscopic picture

Astrovirus

Adenovirus

Coronavirus

Rotavirus

y

Viruses that do not cause diarrhoea: Name. Hepatitis-A virus

Microscopic picture

Polio virus

Echovirus

Coxsackie virus.

Major parasites causing foodborne disease: Protozoa:

Cryptosporidium:Incubation period: 1 to 12 days; 7 days is typical. Diseases it cause: Cryptosporidiosis, also known as crypto, is a parasitic disease caused by Cryptosporidiu. It affects the intestines of mammals and is typically an acute short-term infection. Symptoms: The most common symptom of cryptosporidiosis is watery diarrhea. Other symptoms include: Stomach cramps or pain, Dehydration, Nausea, Vomiting, Fever,Weight loss. Some people with Crypto will have no symptoms at all.

Entamoeba histolytica: Incubation period: Variable, from a few days to several months; usually 2-4 weeks. Diseases it cause: Amebic (or amoebic) dysentery, which is also referred to as amebiasis or amoebiasis, is an inflammation of the intestine. Symptoms: Diarrhea, Asymptomatic, Intestinal damage, Stomach cramps, Nausea, Blood in stool, Loose stool, Abdominal tenderness, Fever, Weight loss.

Giardia:Incubation period: 1 to 2 weeks (average 7 days). Diseases it cause: Giardiasis, an illness that affects the digestive tract. The parasite attaches itself to the lining of the small intestines in humans, where it sabotages the body's absorption of fats and carbohydrates from digested foods. Symptoms: Diarrhea, Gas or flatulence, Abdominal (stomach) pain, Bloating, Belching, Vomiting, Greasy stools that tend to float, Stomach cramps,Upset stomach or nausea. These Giardia symptoms may lead to weight loss and dehydration.

Taxoplasma:Incubation period: 10 - 23 days. Diseases it cause: Toxoplasmosis is a parasitic disease caused by the protozoan Toxoplasma gondii. The parasite infects most genera of warmblooded animals, including humans, but the primary host is the felid (cat) family. The parasite can cause encephalitis (inflammation of the brain) and neurologic diseases and can affect the heart, liver, and eyes (chorioretinitis). Symptoms: Anorexia, weight loss, lethargy, difficulty breathing (because of pneumonia), eye inflammation, and fever. Other symptoms are vomiting and diarrhea, neurological symptoms, swollen lymph nodes, and jaundice.

Helmints: Angiostrongylus:Incubation period: Typically, 13 weeks but has ranged from approximately 1 day to >6 weeks. Diseases it cause: Angiostrongyliasis is caused by Angiostrongylus cantonensis, a nematode parasite that is considered the most common infectious cause of eosinophilic meningitis in humans. Symptoms: Headache, photophobia, stiff neck, nausea, vomiting, fatigue, and body aches. Abnormal skin sensations (e.g., tingling or painful feelings) are more common than in other types of meningitis. A low-grade fever might be noted.

Anisakis: Incubation period: 1 hour 1 week. Diseases it cause: The nematode Anisakis simplex causes anisakidiasis, a disease that often mimics other gastrointestinal diseases. Chronic anisakiasis of the stomach may mimic peptic ulcer, chronic gastritis and gastric cancer. Symptoms: Symptoms vary according to individual susceptibility and to the site of occurrence within the gastrointestinal tract. About 2/3 of patients with anisakiasis have gastric lesions (acute or chronic). Acute stomach anisakiasis occurs with sudden abdominal pain several hours (about 12) after eating raw seafood and may mimic food poisoning, acute gastritis or perforation of stomach ulcer or cholelitiasis.

Ascaris:Incubation period: Variable; life cycle requires 4-8 weeks to be completed; faeces contain fertile eggs about 60 days after ingestion of embryonated eggs. Diseases it cause: Ascariasis is a human disease caused by Ascaris. Infection occurs through ingestion of food contaminated with feces containing Ascaris eggs. The larvae hatch, burrow through the intestine, reach the lungs, and finally migrate up the respiratory tract. From there they are then reswallowed and mature in the intestine, growing up to 30cm (12 in.) in length and anchoring themselves to the intestinal wall. Infections are usually asymptomatic, especially if the number of worms is small. They may however be accompanied by inflammation, fever, and diarrhea, and serious problems may develop if the worms migrate to other parts of the body. Symptoms: Bloody sputum, Cough, Low-grade fever, Vomiting worms, Passing of worm in stool, Gallstone formation, Liver abscesses, Pancreatis, Pulmonary eosinophilia.

Capillaria: Incubation period: Unknown. Diseases it cause: It causes intestinal capillariasis. The infection can be serious because the parasite can multiply to huge numbers in the intestine, and the worms and larvae do extensive damage to the intestinal lining. Symptoms: Diarrhea, abdominal pain, nutritional deficiency, and marked weight loss.

Gnathostoma: Incubation period: 3 - 4 weeks. Diseases it cause: It causes Gnathostomiasis, a disease due to the migration of an immature roundworm. Migration just under the skin causes migratory, painful, itchy swellings. Migration to other tissues can result in cough, blood in the urine, eye involvement and, most seriously, meningitis and encephalitis. Symptoms: Nausea, Vomiting, Malaise, Diarrhea, Muscle pain, Muscle weakness, Cough, Chest discomfort, Localized skin redness, Localized skin pain, Eye symptom, Blood in urine, Itchy skin swellings, Abdominal cramps.

Trichinella: Incubation period: The incubation period varies depending upon the number of parasites in the meat and the amount eaten. It can range from five to 45 days but is usually 10 to 14 days. Diseases it cause: Trichinosis (also termed trichinellosis, trichiniasis, or trichinelliasis), that can infect and damage many body tissues. Although the parasites can pass through the intestinal tract and other tissues, muscle tissues are where the majority of them persist. Symptoms: Trichinosis is usually characterized by two phases; the initial phase (intestinal) of abdominal discomfort, diarrhea, and nausea that begins one to two days after ingestion and the second phase (muscle) of muscle aches, itching, fever, chills, and joint pains that begins about two to eight weeks after ingestion.

Fasciola: Incubation period: The incubation period of eggs varies from 4 to 7 days. Diseases it cause: Fasciola is a genus of trematodes which includes economically important parasite species. Members of genus Fasciola belongs to liver flukes. The disease caused by the fluke is called fascioliasis (also known as fasciolosis). Symptoms: Acute dyspepsia, anorexia, nausea, vomiting, prolonged high fever, abdominal pains and sometime hepatomegaly, hepatic tenderness and urticaria; ectopic infection sites including the lungs, intestinal wall, heart, brain, biliary duct and skin can occur; in endemic areas, acute nasopharyngitis can occur.

Fasciolopsis:Incubation period: Variable; depends on the dose of flukes. Diseases it cause: It causes Fascioliasis, a rare parasitic infectious disease which can cause blockage of the bile ducts in the liver. Symptoms: Fever, nausea, vomiting, appetite loss, indigestion, abdominal pain, diarrhea, cough, eggs in stool, epigastric pain, arthralgias, itching, jaundice, enlarged liver.

Haplorchis:Incubation period: 1 15 days. 1 and 15 days Diseases it cause: The adult fluke attaches itself to the intestinal wall and causes ulcers which may be asymptomatic unless there is an extensive infestation.Eggs Symptoms: Diarhhea, abdominal pain, nausea, loss of appetite.

Paragonimus: Incubation period: Time from infection to oviposition (laying eggs) is 65 to 90 days. Diseases it cause: Paragonimiasis is a food-borne parasitic infection caused by the lung fluke which can cause a sub-acute to chronic inflammatory disease of the lung. Symptoms: Dry-cough, rust-colored sputum, fever, dyspnea, chest pain, malaise, sweats, abdominal pain, diarrhea, urticaria, wheezing, hemoptysis, asymptomatic.

Cysticercus cellulosae:Incubation period: Months to years. Diseases it cause: It causes Cysticercosis (Muscle Cysticercosis, Eye cysticercosis, Neurocysticercosis). If the larvae are ingested then a mild or asymptomatic tapeworm infection occurs. However, ingested eggs pass into the bloodstream where they can then enter various tissues and form the cysts that characterize cysticercosis. Symptoms: Lumps under your skin, Blurry vision, Disturbed vision, Retinal swelling, Retinal detachment, Seizures, Headaches, Difficulty with balance, Swelling of the brain (hydrocephalus).

Spoilage microorganisms: Bacteria. Yeasts Moulds. Useful microorganisms: Lactic acid bacteria (LAB): These ferment CHO into organic acids which inhibit: Salmonella. Staphylococcus. Listeria. Clostridium. E.coli. LAB are found in: Plants. Soil. Animals. Human gut. Food products made with useful organisms:

Fermented meat. Yoghurt. Cheese. Beer. Leavened bread. Soy sauce. Fermented soya bean (Tofu).

WATERBORNE DISEASESWaterborne diseases are caused by pathogenic microorganisms which are directly transmitted when contaminated fresh water is consumed. Contaminated fresh water, used in the preparation of food, can be the source of food borne disease through consumption of the same microorganisms. Waterborne disease can be caused by protozoa, viruses, or bacteria, many of which are intestinal parasites: Protozoal infections: Disease and Microbial Agent Sources of Agent General Symptoms Transmission in Water Supply Protozoan Sewage, nonAbdominal Amoebiasis (Entamoeba treated drinking discomfort, fatigue, (hand-tohistolytica) water, flies in weight loss, mouth) (Cyst-like water supply diarrhea, bloating, fever appearance) Collects on water Flu-like symptoms, Cryptosporidios Protozoan (Cryptosporidium filters and watery diarrhea, loss of is(oral) parvum) membranes that appetite, substantial loss cannot of weight, bloating, be disinfected, ani increased gas, nausea mal manure, seasonal runoff of water. Protozoan Sewage, noncramps, nausea, vomiting, Cyclosporiasis parasite treated drinking muscle aches, fever, and (Cyclospora water fatigue cayetanensis) Untreated water, Diarrhea, abdominal Giardiasis (oral Protozoan discomfort, bloating, and -fecal) (hand- (Giardia lamblia) poor disinfection, Most common pipe breaks, flatulence to-mouth)

intestinal parasite

Microsporidiosi s

Protozoan phylum (Microsporidia), but closely related to fungi

leaks, groundwater contamination, campgrounds wher e humans and wildlife use same source of water. Beavers an d muskrats create ponds that act as reservoirs for Giardia. The genera Diarrhea and wasting in of Encephalitozoo immunocompromised n intestinalis has individuals been detected in groundwater, the origin of drinking water [3]

Parasitic infections: Disease and Transmission

Microbial Agent

Schistosomiasis(immersion) Members of the genus Schistosoma

Dracunculiasis (Guinea Worm Disease)

Dracunculus medinensis

Taeniasis

Tapeworms of the

Sources of Agent in Water Supply Fresh water contaminated with certain types of snails that carry schistosomes Stagnant water containing larvae Drinking water

General Symptoms

Rash or itchy skin. Fever, chills, cough, and muscle aches

Allergic reaction, urticaria rash, nausea, vomiting, diarrhea, asthmatic attack. Intestinal disturbances,

genus Taenia

Fasciolopsiasis

Hymenolepiasis(Dwarf Tapeworm Infection)

Echinococcosis (Hydatid disease)

coenurosis

Ascariasis

Enterobiasis

neurologic manifestations, loss of weight, cysticercosis Fasciolopsis Drinking GIT disturbance, buski water diarrhea, liver contaminated enlargement, with encysted cholangitis, metacercaria cholecystitis, obstructive jaundice. Hymenolepis Drinking Abdominal pain, nana water anorexia, itching contaminated around the anus, with eggs nervous manifestation Echinococcus Drinking Liver enlargement, granulosus water hydatid cysts press on contaminated bile duct and blood with feces vessels; if cysts (usually canid) rupture they can cause containing anaphylactic shock eggs multiceps contaminated increases intracranial multiceps drinking tension water with eggs Ascaris Drinking Mostly, disease is lumbricoides water asymptomatic or contaminated accompanied with feces by inflammation, (usually canid) fever, and diarrhea. containing Severe cases eggs involve Lofflers syndrome in lungs, nausea, vomiting, malnutrition, and underdevelopment. Enterobius Drinking Peri-anal itch, nervous vermicularis water irritability, contaminated hyperactivity and

contaminated with eggs

with eggs Bacterial infection: Disease and Microbial Agent Transmission Clostridium Botulism botulinum Sources of Agent in Water Supply Bacteria can enter a wound from contaminated water sources. Can enter the gastrointestinal tract by consuming contaminated drinking water or (more commonly) food

insomnia General Symptoms Dry mouth, blurred and/or double vision, difficulty swallowing, muscle weakness, difficulty breathing, slurred speech, vomiting and sometimes diarrhea. Death is usually caused by respiratory failure. Produces dysentery li ke symptoms along with a high fever. Usually lasts 210 days. In severe forms it is known to be one of the most rapidly fatal illnesses known. Symptoms include very watery diarrhea, nausea, cra mps, nosebleed, rapid pulse, vomiting, and hypovolemic shock (in severe cases), at which point death can occur in 12 18 hours. Mostly diarrhea. Can cause death in immunocompromise

Campylobacter Most commonly caused by iosis Campylobacter jejuni Cholera

Drinking water contaminated with feces

Spread by the Drinking water bacterium Vibrio contaminated with the cholerae bacterium

E. coli Infection

Certain strains Water contaminated of Escherichia with the bacteria coli (commonly E.

coli)

Mycobacterium M. marinuminfecti marinum on

Dysentery

Legionellosis (two distinct forms: Legionnaires disease and Pontiac fever)

Caused by a number of species in the genera Shigella and Salmonella with the most common being Shigella dysenteriae Caused by bacteria belonging to genus Legionella (90% of cases caused by Legionella pneumophila)

Naturally occurs in water, most cases from exposure in swimming pools or more frequently aquariums; rare infection since it mostly infects immunocompromised in dividuals Water contaminated with the bacterium

d individuals, the very young, and the elderly due to dehydration from prolonged illness. Symptoms include lesions typicall y located on the elbows, knees, and feet (from swimming pools) or lesions on the hands (aquariums). Lesions may be painless or painful. Frequent passage of feces with blood an d/ or mucus and in some cases vomiting of blood.

Contaminated water: the organism thrives in warm aquatic environments.

Pontiac fever produces milder symptoms resembling acute influenza withou t pneumonia. Legionnaires disease has severe symptoms such as fever, chills, pneumonia (with cough that sometimes produces sputum), ata xia, anorexia, muscle aches, malaise and

Leptospirosis

Caused by Water contaminated bacterium of by the animal urine genus Leptospira carrying the bacteria

Otitis Externa Caused by a number (swimmers of bacterial ear) and fungal speci es. Caused by many Salmonellosis bacteria of genus Salmonella Typhoid fever Salmonella typhi

Swimming in water contaminated by the responsible pathogens

occasionally diarrhea and vomiting Begins with flu-like symptoms then resolves. The second phase then occurs involving meningitis, li ver damage (causes jaundice), and renal failure Ear canal swells causing pain and tenderness to the touch Symptoms include diarrhea, feve r, vomiting, and abdominal cramps Characterized by sustained fever up to 40C (104F), profuse sweating, diarrhea, less commonly a rash may occur. Symptoms progress to delirium and the spleen and liver enlarge if untreated. In this case it can last up to four weeks and cause death. Symptoms include explosive, watery diarrhea, nausea, vomiting, abdominal

Drinking water contaminated with the bacteria. More common as a food borne illness. Ingestion of water contaminated with feces of an infected person

Vibrio Illness

Vibrio vulnificus, Vibrio alginolyticus, and Vibrio

Can enter wounds from contaminated water. Also got by drinking contaminated water or

parahaemolyticu s Viral infections: Disease and Microbial Transmission Agent Adenovirus Adenovirus infection

eating undercooked oysters.

cramps, and occasionally fever

Sources of Agent in Water Supply Manifests itself in improperly treated water

General Symptoms

Gastroenterit is

SARS (Sever e Acute Respiratory Syndrome) Hepatitis A

Astrovirus, Calicivirus, Enteric Adenovirus, and Parvovirus Coronavirus

Symptoms include common cold symptoms, pneumonia, croup, and bronchitis Manifests itself in Symptoms improperly treated include diarrhea, nausea, vomi water ting, fever, malaise, and abdominal pain

Hepatitis A virus (HAV)

Poliomyelitis (Polio)

Poliovirus

Manifests itself in Symptoms improperly treated include fever, myalgia, letharg water y, gastrointestinal symptoms, cough, and sore throat Can manifest itself Symptoms are in water (and food) only acute (no chronic stage to the virus) and include Fatigue, fever, abdominal pain, nausea, diarrhea, weight loss, itching, jaundice and depressi on. Enters water 90-95% of patients show no through symptoms, 4-8% have minor the feces of symptoms (comparatively) infected with delirium, individuals headache, fever, and occasional seizures, and spastic paralysis, 1% have symptoms of non-paralytic aseptic meningitis. The rest have serious symptoms resulting in paralysis or death

Polyomavirus infection

Two of Polyomavirus : JC virus and BK virus

Very widespread, can manifest itself in water, 80% of the population has antibodies to Polyomavirus

BK virus produces a mild respiratory infection and can infect the kidneys of immunosuppres sed transplant patients. JC virus infects the respiratory system, kidneys or can cause progressive multifocal leukoencephalopathy in the brain (which is fatal)