Examination 1New and reemerging infectious diseases are becoming a contemporary problem not only for the medical area but also for the food industry.
Note: Information to answer the questions below can be obtained by accessing the articles listed under "Emerging Infectious Diseases." on the Home Page for this course and the January 17, 1996 issue of JAMA.
Name five (5) infectious diseases which would be considered new or reemerging. Include as many of the 5 as possible that could be considered foodborne or waterborne.
Discuss the factors responsible for the emergence of new infectious diseases.
Discuss the prevention strategy proposed for the emerging infectious disease threats in the United States.
You and a friend had lunch at a local eatery. Your sandwich was contaminated with Salmonella while your friend's sandwich was held under conditions which permitted sufficient growth of Staphylococcus aureus to produce enterotoxin. Both of you consumed sufficient food to make you ill. Discuss the host defenses which would be activated to combat these pathogens. Indicate any differences in host defenses for the type illness.
Give an example of a gastrointestinal infection and an example of a microbial induced foodborne intoxication. Compare the basic characteristics of the agents associated with the infection and the agents associated with the intoxication. Indicate the mechanisms by which each influences pathogenic processes and produce the characteristic symptoms. Describe the defense mechanisms which are important in protecting the host animal from each of these agents.
Compare the basic characteristics of the agents associated with foodborne infections and the agents associated with foodborne intoxication. Indicate the mechanisms by which each influences pathogenic processes and produce the characteristic symptoms.
Define foodborne disease, outbreak, and case.
Compare the sequence of events required for a foodborne outbreak due to bacteria and chemical.
You have been hired by the World Health Organization (WHO) to establish a foodborne disease surveillance system in a developing third world country. Discuss the type of surveillance and reporting system you would establish in order to determine the incidence of foodborne illness in this country. Include definitions for foodborne disease, outbreak, case, and severity in your discussion.
Describe the main nonspecific and specific defense mechanisms which are important in protecting humans from foodborne pathogens.
Give five types of fish and shellfish poisonings, and the name(s), characteristics, and source(s) of the etiologic agent(s) responsible for each.
Discuss the major toxins responsible for fish and shellfish poisonings and the source of each toxin (include, if known, the responsible organism(s).
Discuss measures for controlling fish and shellfish poisonings.
Describe four (4) types of illnesses associated with toxic marine animals. Include how they become toxic, etiologic agent(s) involved, and control mechanisms used to reduce incidences of human illness.
Discuss the etiologic agent(s) responsible for staphylococcal intoxication, including when and how produced, major characteristics of the agent(s), the amount required to cause illness in humans, and the major symptoms of the disease.
Using an outbreak of staphylococcal intoxication either passed out in class or from the readings, describe the sequence of events that resulted in the outbreak. DO NOT USE THE CASE IN THE HANDOUT MATERIAL USED TO ILLUSTRATE THE SEQUENCE OF EVENTS.
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Examination 2Define mycotoxins
Discuss the biosynthesis of mycotoxins.
Name five mycotoxins and a genus that contains a species that can produce each.
Describe how mycotoxins can be controlled
Discuss the differences in causative organism, etiologic agent, source of organism and etiologic agent, and mode of action of the etiologic agents responsible for botulism and salmonellosis.
Discuss the differences in etiologic agent, source of organism and etiologic agent (where produced), and mode of action of the etiologic agents responsible for botulism, Clostridium perfringens gastroenteritis, and Staphylococcal intoxication.
Discuss the etiologic agent(s) and the type of illness involved in Bacillus cereus gastroenteritis.
(10 points) Discuss what determine if ingested Salmonella reach the gastrointestinal tract.
Discuss each of the following for the foodborne illness listed below:
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Examination 3Discuss the mechanism(s) involved in their pathogenicity when each of the following bacteria are ingested in a food:
Discuss in detail the virulence factors (encoded on plasmid and/or chromosome, size, etc.) and pathogenic mechanism(s) by which the following organisms produce a foodborne disease in humans. Include the major symptoms of the disease and what is responsible for the symptom.
Discuss how you would determine if an outbreak of bloody diarrhea was due to Shigella sonnei, Escherichia coli, or Campylobacter jejuni.
Discuss the difference(s) between virulent and avirulent Yersinia enterocolitica.
Define siderophores and discuss their role in the pathogenicity of bacteria.
Describe one foodborne disease where siderophores are very important.
Discuss the causes and pathogenic mechanism(s) involved in taeniasis and cystericercosis.
Give the total number of confirmed outbreaks and cases that occurred in the United States between 1983 and 1987 for the bacteria listed below. Also indicate the number of outbreaks and cases that are estimated to have occurred for each of these organisms. Rank each bacteria according to its prevalence as a bacterial etiologic agent. Indicate the source of your information.
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Examination 4
On April 2 you received notice from George LaMont of a possible foodborne outbreak. The initial report involved an individual who was hospitalized at UK Medical Center with a Salmonella Group D infection as determined through a stool culture. Two additional cases were reported on April 3. Initial investigations indicated a common source single event exposure at a wedding reception on Saturday, March 29.
A guest list of 67 persons attending the reception was obtained and a total of 62 interviews were
conducted (See attached Form C, Parts 1 & 2). The meal consisted of Roast beef, Potato
salad, macaroni salad, Baked beans, Sausage and peppers, Cheese and Ham platter, Rolls, Wedding
cake, and various beverages.
Define how you would classify a person as a case in this outbreak.
Use Form H (attached) to prepare a Food-Specific Attack Rate Table.
Draw an epidemic curve.
Prepare a table showing the following
Prepare a table showing the frequency of symptoms and signs.
Prepare a table showing the following
Calculate Chi-square for the food you believe is responsible for the outbreak. Calculate Chi-square even if a cell is less than 5. Show all calculations.
Discuss the mechanism(s) involved in the pathogenicity of the three vibrios discussed in lecture.
Discuss four general mechanisms involved in the pathogenicity of microorganisms involved in foodborne illness. Indicate a species for each mechanism discussed.
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