Foodborne infection

Ministry  of  Agriculture  of  Russian  Federation

The Department of Scientific and Technological Policy and Education

FSBEI of HPE «Krasnoyarsk State Agrarian Univercity»

 

 

 

 

 

 

Report

«Foodborne infection»

 

Done by

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Krasnoyarsk 2013

Body of paper

Introduction

1. Salmonellosis by Salmonella enterica
2. Listeriosis by Listeria monocytogenes
3. Pathogenic Esherochia coli
4. Shigellosis ( Bacillary dysentery) by Shigella species
5. Campylobacteriosis by Campylobacter species
6. Yersiniosis by Yersinia enterocolitica

Conclusion

References

Annatation

 

 

 

 

 

 

 

 

 

 

 

Introduction

 

My specialti is veterinary medicine. Veterinary medicine is the application of medical, diagnostic, and therapeutic principles to companion, domestic, exotic, wildlife, and production animals. Veterinary science is vital to the study and protection of animal production practices, herd health and monitoring the spread of disease. It requires the acquisition and application of scientific knowledge in multiplie disciplines and uses technical skills directed at disease prevention in both domestic and wild animals.

The aim of this paper is to find some optimal ways of the problem of foodborne infections in the use of animal products.

Foodborne infection occurs from the consumption of food (and water) contaminated with pathogenic enteric bacteria and viruses. Many pathogens are included in this group. However, many are involved more frequently than others, and they are discussed in this chapter. The discussions include their relative importance, characteristics, food association, toxins, disease symptoms, and prevention. For some, detection methods and case histories are also included.

 

 

 

 

 

 

 

Salmonellosis by Salmonella enterica

 

Salmonella enterica serovar Typhimurium (Typhimurium) is an important pathogen that infects a broad range of hosts. In humans, Typhimurium causes a gastroenteritis characterized by vomiting, diarrhea, and abdominal pains. Typhimurium infection occurs mainly through the ingestion of contaminated food including poultry, pork, eggs, and milk (http://www.biomedcentral.com/1471-2180/9/3). 

Salmonella are natural inhabitants of the gastrointestinal tracts of domesticated and wild animals, birds, pets (including turtles and frogs), and insects. In animals and birds, they can cause salmonellosis and then persist in a carrier state. Humans can also be carriers following an infection and shed the pathogens through t'eces for a long time. They have also been isolated from soil, water, and sewage contaminated with t'ecal matters.

There is a high incidence of salmonellosis amongzoo animals. http://kubanvet.ru/journal_n3_20128.html

 

According to research conducted by veterinary laboratories of Krasnodar region in 2011 most distinguished culture of Salmonella was group D. Most often the disease was observed in birds.( http://kubanvet.ru/journal_n3_20128.html)

Human saimonellosis is different from typhoid and paratyphoid fever caused by Sal. ryphi and Sal. paratyphi, respectively. Although there are some Salmonella serovars specific against different animals and birds, all are considered to be potential human pathogens capable of causing saimonellosis. Foodborne saimonellosis is characterized by gastrointestinal disorder manifested predominantly by diarrhea and abdominal cramp. A dose of > 10⁵ cells is needed to be consumed to initiate infection; however, there are some virulent strains where ingestion of fewer cells can cause the disease. Strains that are sensitive to gastric acidity generally need more cells to establish in the intestine and cause the disease; conversely, acid-resistant strains may require fewer cells to cause the disease. The infectious dose decreases if the pathogen is consumed with food that neutralizes the stomach acidity such as milk, cheese, and so forth. Progression of disease also depends on the physiological state of the host. Elderly persons with high gastric pH are vulnerable to saimonellosis.

Following ingestion, the pathogen colonizes in the small and large intestines and most of the pathological lesions are reported to be found in the large intestine rather than in the small intestine. The organism adheres to the mucosal ceils using fimbriae or other adhesion factors and then actively invades mucosal cells .

The symptoms appear within 8—12 h. generally in 24—36 h. The symptoms last for about 2-3 days, but in certain individuals can linger tor a long time. An individual remains in a earner state for several months following recovery.

Not ail individuals ingesting the same contaminated foods will develop symptoms nor will those who develop symptoms have all the symptoms in the same intensity. It varies with the state of health and natural resistance of an individual. The general symptoms are abdominal cramps, diarrhea, nausea, vomiting, chills, fever, and prostration. It can be fatal, especially to the sick, infants, and the elderly.

Setting the sensitivity to antibiotics showed that Salmonella isolates are resistant to canamycin. carbenicillin. ampicillin. amoxicillin and others. Found that Salmonella isolated from reptiles, acquire resistance to antibiotics quickly. http://kubanvet.ru/journal_n3_20128.html

Raw foods of animal origin that are heat-treated before consumption can have Salmonella. However, in the United States (and other developed countries), as per regulatory requirements, heat-treated and ready-to-eat foods that contain Salmonella in portions (samples) tested are considered to be adulterated and should not be sold. Many food-processing industries have in-house Salmonella (as well as several other pathogens) surveillance programs to control the presence of Salmonella in their products. The regulatory agencies also have programs to educate consumers at home and food handlers in food service places to control Salmonella contamination in foods. These include proper cooking of foods (minimum to pasteurization temperature and ;ime. such as 71.7°C for 15 s or equivalent) and prompt cooling (to 3-4°C or freezing, if not used in 2 h); prevention of cross-contamination of ready-to-eat food with a raw food through cutting boards, equipment, utensils, and hands; use of proper sanitation and personal hygiene: not handling a food while sick: and properly reheating a food refrigerated for a long time.

LISTERIOSIS BY LISTERIA MONOCYTOCENES

Disease caused by the bacterium Listeria monocytogenes. The bacterium has been isolated from humans and from more than 50 species of wild and domestic animals, including mammals, birds, fish, crustaceans, and ticks. It has also been isolated from environmental sources such as animal silage, soil, plants, sewage, and stream water. http://universalium.academic.ru/142449/listeriosis

  Sheep, cattle, goats, horses, pigs, and other domesticated animals are susceptible to the infection, which may result in encephalitis, septicemia, and spontaneous abortion. In animals listeriosis is also known as circling disease, because some infected animals walk in circles. http://universalium.academic.ru/142449/listeriosis

Human listeriosis has been recognized for a long time. However, the presence of Lis. monocyiogenes in many foods of animal and plant origin and illnesses resulting from the consumption of contaminated foods were recognized rather recently in 1980s. Human listeriosis is considered by some to be an opportunistic rare disease. Individuals with normal health may not develop the symptoms or show a very mild enteric form of the disease. However, it is highlv fatal to fetuses, newboms. infants, the elderly, pregnant women, and immunocompromised people, such as those with cancer (receiving chemotherapy), renal diseases, heart diseases, and AIDS. Individuals receiving organ transplants and treated with immunosuppressive drugs are also susceptible to listeriosis. In addition, its ability to grow in many foods at refrigerated temperature helps the organism to reach from a low initial level to an infective dose level during storage of refrigerated foods, which include those that originally harbored the pathogen and those that were postheat contaminated. The increase in consumption of many types of ready-to-eat foods that are stored for fairly long periods of time. and the fact that many of these foods are consumed without properly reheating or by microwave heating, has given an edge for this pathogen to cause the disease. Many technological developments used for the production of these ready-to-eat foods may have steps that can contaminate food with the pathogens in low levels, which then can reach a higher level during subsequent refrigerated storage prior to consumption. Any temperature abuse, even for a short time, can accelerate the growth rate.

It is quite clear that many of the above conditions have given an advantage to Lis. Monocyiogenes to become a newly emerging foodborne pathogen in many countries. However, an understanding of the type of foods that ore mostly involved in listeriosis. the food processing steps that can contaminate ready-to-eat foods with this pathogen, and the special groups of people that are most su sceptible tothe disease, helped the regulatory agencies develop procedures to reduce the number of foodborne listeriosis. These have been achieved through the changes in the processing steps and testing of the foods so that contaminated ready-to-eat foods do not reach the consumers, and by educating the susceptible consumer groups about food choices, eating habits, and sanitary practices in food preparation. The infectious dose for this pathogen varies between individuals: immunosuppressed being most susceptible. Since this pathogen is highly infectious. there is no study done with volunteer feeding trials to establish infectious dose. On the basis of the epidemiological data, it is estimated to be in the range of 100-1000 cells in immunocompromised host and because of its high fatality rate, the U.S. government has established a "zero" tolerance policy for this pathogen in ready-to-eat products.

Listeria monocytogenes causes two forms of diseases: (1) febrile gastroenteritis and (2) invasivesystemic diseases.

Febrile Gastroenteritis

The exact mechanism of gastroenteritis is not known: however, epidemiological study suggests that this form is mostly associated with healthy individuals and the infectious dose is in the range of 10^S-10'° cells. Mo.st often, the symptoms appear within 1-7 days following ingestion and include mild flu-like symptoms with slight fever, abdominal cramps, and diarrhea. The symptoms subside in a few days, but the individual sheds Lis. monocytogenes in the feces for some time.

Invasive Systemic Disease

This form of disease is associated with immunologically challenged populations. These groups include pregnant women, unborn fetuses, infants, elderly people with reduced immunity due to diseases, and people taking special medications, such as steroids and chemotherapeutic agents to treat cancer. The infective dose in these people is considered to be about 100-1000 cells. Following ingestion. bacteria pass through the stomach unharmed and then reach the small intestine. GAC (glutamate decarboxylase) helps bacterial survival in the stomach acid while bile salt hydrolase protects Lis. monocytogenes from antimicrobial action of bile salts. Bacteria rapidly pass througt intestine via Peyer's patch, a localized lymphatic tissue, where M cells phagocytose and allov bacterial translocation to the lamina propria and then, to blood circulation. Lis. monocytogenes cai also actively pass through the epithelial barrier .

 

 

PATHOGENIC ESCHERICHIA COLI

Escherichia coli is the predominant nonpathogenic facultative flora of the human intestine. Some E. coli strains, however, have developed the ability to cause disease of the gastrointestinal, urinary, or central nervous system in even the most robust human hosts. Diarrheagenic strains of E. coli can be divided into at least six different categories with corresponding distinct pathogenic schemes. Taken together, these organisms probably represent the most common cause of pediatric diarrhea worldwide. Several distinct clinical syndromes accompany infection with diarrheagenic E. coli categories, including traveler's diarrhea (enterotoxigenic E. coli), hemorrhagic colitis and hemolytic-uremic syndrome (enterohemorrhagic E. coli), persistent diarrhea (enteroaggregative E. coli), and watery diarrhea of infants (entero-pathogenic E. coli). This review discusses the current level of understanding of the pathogenesis of the diarrheagenic E. coli strains and describes how their pathogenic schemes underlie the clinical manifestations, diagnostic approach, and epidemiologic investigation of these important pathogens. http://gastroportal.ru/php/content.php?id=101485

Since its discovery in 1885 by Theodor Escheric, Escherichia coli was considered as a harmless. Gram-negative, motile, nonsporulating, rod-shaped, facultative anaerobic bacterium, a normal inhabitant of the intestinal tract of humans and warm-blooded animals and birds. Because it is normally present at a very high level (in millions per gram of the content of the large intestine), foi long time it has been used as an index organism of possible fecal contamination and the presence enteric pathogens in food and water . Since the mid-1940s, evidence has accum lated that certain Esc. coli strains cause diarrhea, particularly in infants, and they were designated EPEC. However, current evidence indicates that pathogenic strains of Esc. coli are more than 01 type. They are subdivided into six groups based on their ability to produce toxins, to adhere and invade epithelial cells. They are: Enterotoxigenic Esc. coli (ETEO. Enteropathogenic Esc. cc (EPEC), Enteroinvasive Esc. coli (EIEC). Enterohemorrhagic Esc. coli lEHEC). Enteroaggregati' Esc. coli (EAEC), and Diffuse-adhering Esc. coli (DAEC). The mechanism of infection and tl symptoms produced by these are somewhat distinct but may show some overlapping characteristii .

Enteropathogenic Escherichia coli (EPEC)

These strains are important in infant diarrhea worldwide, especially in places with poor sanitation. They are transmitted directly or indirectly through human carriers. Several serotypes (O111:H12; O55:H6) are implicated in waterbome and foodborne disease outbreaks in different countries. These pathogens do not produce any toxins but they intimately attach to the epithelial cells with the help of bundle-forming pili (bfp) and a virulence factor called attachment—effacemem factor (EAF). Intimate contact results in severe lesion on the epithelial layer called attachment—effacement lesion that destroys the absorptive villi resulting in malabsorption and diarrhea . One needs to ingest high numbers of cells 110⁶-10⁷to develop the symptoms, which could appear within 3 h. The predominant symptoms are gastroenteritis, profuse watery diarrhea, vomiting, and low grade fever.

Although there is no clear differentiation for these four subgroups, both EIEC and EHEC strains seem to fit with the enteric pathogens associated with foodborne infection. Thus these two groups are discussed in this chapter. Both EPEC and ETEC groups are included in the chapter discussing toxicoinfection .

Enteroinvasive Escherichia coli (EIEC)

These strains are known to cause dysentery, like shigellosis. They first bind to epithelial cells and invade and move from cell-to-cell spreading the infection in the intestines . Cell damage results in bloody mucoid diarrhea similar to bacillary dysentery caused by Shigelltt. Human carriers. directly or indirectly, spread the disease. Ingestion of as many as 10⁶ cells may be necessary for an individual to develop the symptoms. An outbreak in the United States as early as 1971 was recognized from the consumption of imported Camembert cheese contaminated with serotype O124:H17. The pathogens produce virulence factors that are responsible for invasion to epithelial cells and enable the pathogen to move from cell-to-cell and set up infection in the colon. The genes for invasion are encoded in a 140-MDa plasmid.^.

The disease and symptoms are like shigellosis. Following ingestion of the pathogen (about 10⁶ cells) and incubation period, symptoms appear as abdominal cramps, profuse diarrhea, headache, chills, and fever. A large number of pathogens are excreted in the feces. The symptoms can last for 7-12 days, but a person can remain a carrier and shed the pathogens in feces for a long time.^.

The pathogen is sensitive to pasteurization temperature. Thus proper heat treatment, elimination of postheat contamination for a ready-to-eat food, and refrigeration of a food soon after preparation are necessary to control the disease. In addition, proper sanitation at all stages of food processing and handling will be an important factor. Finally, individuals suspected of being earners should not handle food, especially ready-to-eat food.

SHIGELLOSIS (BACiLLARY DYSENTERY) BY SHICELLA SPECIES

The genus Shigella contains four species: Shigella dysenteriae. Shi. flexneri, Shi. boydii. and Shi. Sonnet, and each species has several serovars. Shi. dysenteriae is responsible for brisk but deadly epidemic outbreak. Shi.flexneri and Shi. sonnei cause endemic disease, while Shi. boydii causes rare disease. Only human and some primates serve as their hosts. The organisms are either transmitted directly through fecal-oral routes or indirectly through fecal-contaminated food and water. While in most developed countries transmission through drinking water has been reduced, in developing countries contaminated drinking water is a major cause of shigellosis. The disease is prevalent in some geographic locations, particularly in Asia, Mexico, and South America. It occurs more frequently in places with poor sanitation. In the United States, shigellosis occurs more among migrant workers, on Indian reservations, in poor urban institutions, and in day-care centers. Children below 5 years of age are more affected. In developing countries, there is a high fatality rate among children suffering from shigellosis. In general, food service establishments have been implicated in more outbreaks, and poor personal hygiene has been the major cause. The disease is more predominant during late spring to early fall. The infective dose is very low. ca. 10 cells in adults. Bacteria, after ingestion with contaminated food or beverages, pass through stomach and small intestine and reach the large intestine. The disease is restricted to the intestinal mucosa and invades epithelial cells of colon. Shigellae are also taken up by M cells in Fever's patch, which also facilitate invasion. Bacteria produce large numbers of virulence proteins such as—IpaA. IpaB. IpaC, IpaD, IcsA, and so forth that allow bacteria to invade host epithelial cells, to allow cell-to-cell movement by initiating actin polymerization, and to induce programmed cell death. LPS produced by Shigella also activates macrophages to produce ctоine (IL-1) that induces inflammation. The symptoms occur in 12 h to 7 days, but generally in 1-3 days. In case of mild infection, symptoms last for 5-6 days, but in severe cases, symptoms can linger for 2-3 weeks. Certain individuals might not develop symptoms. An infected person sheds the pathogens long after the symptoms have stopped. The symptoms are the consequence of both invasiveness of epithelial mucosa and the enterotoxin and include abdominal pain, diarrhea often mixed with blood, mucus and pus. fever, chills, and headache. Generally, children are more susceptible to the disease than adults.

The most common symptoms are diarrhea, fever, nausea, vomiting, stomach cramps, flatulence, and straining to have a bowel movement. The stool may contain blood, mucus, or pus (e.g. dysentery). In rare cases, young children may have seizures. Symptoms can take as long as a week to show up, but most often begin two to four days after ingestion. Symptoms usually last for several days, but can last for weeks. Shigella is implicated as one of the pathogenic causes of reactive arthritis worldwide. http://en.academic.ru/dic.nsf/enwiki/55552

 

Foodbome shigellosis, at least in the developed countries, is caused by contamination of foods by food handlers shedding the pathogen in the feces and having poor personal hygiene. To prevent contamination of ready-to-eat food by such individuals, it is necessary to forbid them to handle such foods. Quite often, this is impossible, especially if the individual is a carrier. Proper education of the food handlers about the importance of good personal hygiene and the need to not handle food if one suspects having a digestive disorder is important. Use of rigid sanitary standards to prevent cross-contamination of ready-to-eat food, use of properly chlorinated water to wash vegetables to be used for salads, and refrigeration of foods are necessary to reduce foodborne shigeilosis. "'

 

CAMPYLOBACTERIOSIS BY CAMPYLOBACJER SPECIES

Campylobacteriosis is an infectious disease caused by the Campylobacter bacteria. Campylobacter jejuni, C. fetus, and C. coli are the types that usually cause campylobacteriosis in people. C. jejuni causes most cases of the illness.According to the CDC, C. jejuni is the leading cause of bacterial diarrheal illness in the United States, affecting an estimated 2.4 million people every year. The bacteria cause between 5 percent and 14 percent of all diarrheal illness worldwide. C. jejuni primarily affects children under 5 years old and young adults (15-29 years old). Health care providers report more than 10,000 cases to the CDC yearly. In the United States, few people die from Campylobacter infection. http://minskclinic.by/studies/2-1-fitnessandnutrition/study43.php

Genus Campyiobacter contains 16 species and 6 subspecies and many of them cause human gastroenteritis; however. Cam. jejuni and Cam. coli are considered the most common causative agents of human diarrhea! disease in many countries worldwide. In many countries, the number of cases of campylobactenosis probably far exceeds the combined number of salmonellosis and shigellosis cases. Epidemiological data have confirmed this in Canada, the U.K., and Scotland. Isolation of Campylobacrer spp. from a suspected sample requires specific methods. After developing the method and incorporating it to isolate suspected foodborne pathogens. Cam. jejuni has been confirmed as a causative agent in many foodborne illnesses. The foods implicated most often in campylobacteriosis were raw milk and improperly cooked chicken. Although several Campylobacrer spp. have been associated with foodborne campylobacteriosis. Cam. -ejitni has been isolated in most incidents; the discussion here is on Cam. jejuni.

The infective dose for campylobacteriosis is considerably low only ca. 500 cells. Following inges-tion, motile bacteria reach to the mucus layer. Chemotaxis and requirement for iron drive the bacteria to reach to the epithelial surface where they colonize. Toxin production causes cell damage (death), inflammation, and fluid loss resulting in diarrhea that appears in 2-5 days. Symptoms generally last for 2-3 days, but can linger for 2 weeks or more Persons with no visible symp.toms can shed the cells in feces for a long time. The main symptoms are enteric and include abdominal cramps, profuse diarrhea, nausea, and vomiting. Other symptoms include fever, headache, and chills. In some cases, bloody diarrhea has been reported. An individual can have a relapse of symptoms after a short interval.

Consequence of campylobacteriosis in humans result in a chronic disease called Guillain-Barre syndrome, a debilitating generalized paralysis. Chronic infection promotes antibody production against Campylobacter antigen, which reacts with nerve cells causing impaired nerve function. Another consequence of campylobacteriosis is arthritis, also known as Reiter's syndrome

It is rather difficult to control the access of Cam. jejuni to raw foods, particularly foods of anim; origin. However, proper sanitation can be used to reduce its load in raw foods during productioi processing, and future handling. Preventing consumption of raw foods of animal origin, hea treatment of a food when possible, and preventing postheat contamination are important to contn campylobacteriosis in foods of animal origin. Contamination of vegetables can be controlled by n< using animal feces as fertilizer and not using contaminated water to wash vegetables (especial ready-to-eat types). Contamination from humans can be reduced by establishing good person hygiene and not allowing sick individuals ;o handle foods, especially ready-to-eat foods