Exam 1

Where does enteric bacteria live

large intestine

What do enteric bacteria do

ferment sugars to a variety of end products

Proteus

genus containing rapidly motile cells; capable of swarming, capable of moving

What are 2 examples of gram positive firmicutes

bacilli and clostridia

What is the transmission of foodborne pathogens

oral route

What are 3 contamination routes of foodborne pathogens

handling/processing, cross contamination and organism

What are 2 examples of diseases humans carry from foodborne pathogens

rotavirus and shigella

What are 2 examples of diseases animals carry from foodborne pathogens

Salmonella and E. Coli

What are the points of contamination in the food chain

on the farm/field, slaughter plant, during processing, point of sale and in the home

What do perishable foods have a higher count of

moisture

What causes a higher susceptibility to food spoilage

moisture content

How is microbial growth similar to bacterial growth

Follows the normal pattern of bacterial growth but food spoilage is observed during the last few population doubling

What are 3 methods for slowing food spoilage

pickling, heating and dehydration

Food poisoning

Disease that results from ingestion of foods containing preformed microbial toxins

Food infection

Microbial infection resulting from the ingestion of pathogen-contaminated food followed by growth of pathogen in the host

What is the difference between food poisoning and infection

poisoning occurs from toxins after the food is ingested and food infection occurs from toxins that were already in the food before ingestion

Who regulates and surveillances our food supply

CDC

What are exotoxins

proteins released from the pathogen cell as it grows

What are the three categories of exotoxins

cytolytic, AB and superantigen

What is staphylococcal food poisoning

Caused by toxins produced by Staphylococcus aureus

How many cases of staphylococcal food poisoning are there per year

185,000

What are 2 characteristics of Staphylococcal Enterotoxin B

soluble in water and over stimulates the immune system

What are 3 clinical signs of inhalation of staphylococcal food poisoning

chills, myalgia and high fever

What are 3 clinical signs of ingestion of staphylococcal food poisoning

Cramping, vomiting and nausea

What is different about clostridial food poisoning

It produces endospores that may not be killed during cooking/canning process

How many people suffer from Clostridial food poisoning each year

248,000

Botulism

a severe and often fatal food poisoning

What is the most common food botulism comes from

canned items

What are AB toxins

Work by binding to host cell receptor (B subunit) and transferring damaging agent (A subunit) across the cell membrane

What are 2 examples of AB toxins

Tetanus and botulinum

What are the 3 forms of botulism in humans

foodborne, wound and infant

What are 3 symptoms of Botulism in humans

paralysis, vomiting and diarrhea

What are 3 causes of botulism in animals

forage poisoning, contaminated feed and spoiled stores silage/grain

What are 2 examples of food infection

listeria and salmonella

What are most E. Coli

Non pathogenic

What are all pathogenic strains

intestinal parasites

What produces verotoxin

Enterohemorrhagic E. Coli

Enterotoxigenic

From contaminated food and water and often affects infants and those traveling to other countries

Enteroinvasive

produces no toxins and enters the epithelial cells

Enteropathogenic

From contaminated food or water that has fecal matter in it

How many cases of salmonella are there per year

40,000-45,000

What 2 animals harbor salmonella

chickens and pigs

How does salmonella work

ingested in food or water invades phagocytes and grows as an intracellular pathogen

What are the top 3 salmonella carriers

turtles, chickens and dogs

What are 2 human transmissions of salmonella

fecal material from livestock or from contaminated items

What are 2 animal transmissions of salmonella

carried asymptomatically or vertical (mother gives to eggs)

What are 3 symptoms of acute enteritis in animals

diarrhea, dehydration and depression

Plasmids

genetic elements that replicate independently of the host chromosome

R Plasmids

Resistant plasmids; confer resistant to antibiotics and other growth inhibitors

What are 2 virulence factors in plasmids

enables pathogens to colonize and cause host damage

How do Protists spread

in foods contaminated by fecal matter in water used to wash, irrigate, or spray crops (typically fresh fruit)

Prions

Proteins that adopt novel conformations that inhibit normal protein function and cause degeneration of neural tissue

What is the most common source of infectious diseases

water

What are the 2 primary treatments for waste water purification

Screening and sedimentation

What are the steps in drinking water purification

Remove sedimentation, coagulation, filtration, chlorination and storage

What is the most commonly used method for testing drinking water

IDEXX Colilert

What are 2 waterborne microbial diseases

cholera and typhoid fever

What are the 2 common sources of waterborne disease transmission

potable water and recreational water

How is cholera transmitted

through ingestion of contaminated water

What disease is transmitted in aerosols

Legionellosis

Where is legionellosis commonly found

in terrestrial and aquatic habitats and cooling towers and evaporative condensers

What is the major difference between salmonella and E. Coli

you can catch E. coli from person to person contact but you can only get Salmonella from ingestion

What are sexually transmitted diseases caused by

Bacteria, viruses, protists and fungi

Where are the pathogens from STIs found

body fluids from the genitourinary tract that are exchanged during sexual activity

What are 3 sexually STIs

Gonorrhea, syphilis and chlamydiosis

How are STIs transmitted

Genitourinary tract

What two STIs are treatable

Gonorrhea and syphilis

What are the characteristics of Gonorrhea

its prevalent and often asymptomatic in women

What are the characteristics of syphilis

has low prevalence and exhibits very obvious symptoms

What does estrogen do

promotes motility of sperm and controls pH in the vaginal tract

What are the symptoms of Gonorrhea in females

mild vaginitis, pelvic inflammatory disease and can cause sterility

What are the symptoms of Gonorrhea in males

infection of the urethral canal

What are 3 key genera of spirochetes

Treponema, Borrelia and Spirochaeta

Where are spirochetes spread

aquatic environments and in animals (found in the rumen)

What is different about Leptospira and Leptonema

strictly anaerobic

Who are the natural hosts of Leptospira

rodents

What is the causative agent of Lyme disease

Borrelia

What is syphilis caused by

treponema pallidum

How is syphilis transmitted

at the same time as gonorrhea and from an infected woman to the fetus during pregnancy

What are the three stages of syphilis called

primary, secondary and tertiary

What is the leading sexually transmitted disease

Chlamydia

What is the Chlamydia life cycle

Obligate intracellular bacteria, elementary body (infectious and survives for months in environment) and reticulate body (non-infectious)

What is different about Chlamydia

remains infectious for months and remains viable on surfaces for 2-3 weeks

What is anthrax

a spore bacterium

What does the spore in anthrax require

poor nutrient conditions and a presence of oxygen

What is the transmission of anthrax in humans

cutaneous, Inhalational and gastrointestinal

What is cutaneous transmission

contact with infected tissues (wool, hide, etc) and biting flies

What is Inhalational transmission

tanning hides, processing wool or bone

What is gastrointestinal transmission

undercooked meat

What is the animal transmission for anthrax

ingestion from contaminated soil or contaminated feed or bone meal

What is the most common type of anthrax

cutaneous (95%)

What are symptoms of cutaneous anthrax

severe edema, fever and malaise

What are the symptoms of gastrointestinal anthrax

severe gastroenteritis

What are the symptoms of Inhalational anthrax

milked fever, and malaise in initial phase and severe respiratory distress, dyspnea, strider, cyanosis and death in second phase

How is anthrax diagnosed in humans

serology, ELISA and nasal swabs

What are the treatments for anthrax

penicillin and Ciprofloxacin

What are some prevention and control methods for anthrax

veterinary supervision, trade restrictions and safety practices

What are some characteristics of Brucellosis

facultative, can live within the host and environmental persistence

What are 2 names of human disease of Brucellosis

malta and gastric fever

What are 2 names of animal disease of Brucellosis

Bang’s disease and enzootic abortion