Reality Check: Harmful Microbes

Question 1

Outbreak

Answer 1

When two or more people become ill with similar symptoms from consuming the same food from the same source, and the epidemiological investigation implicates, either directly or indirectly, the same food from the same source as the cause of the illness

Question 2

Outside of unknown agents, what is responsible for the most foodborne disease outbreaks?

Answer 2

Bacterial agents

Question 3

What is the difference between E. coli K-12 and E. coli O157:H7?

Answer 3

K-12 is a “lab rat” and O157:H7

Question 4

Intoxication

Answer 4

Ingest, pre-formed toxin

Question 5

Toxicoinfection

Answer 5

Ingest large number of viable cells, which release toxins as they sporulate or die

Question 6

Infection

Answer 6

Ingest viable cells, which grow causing sickness

Question 7

In foodborne pathogens organism presence is ______________

Answer 7

suggestive; toxin presence is definitive

Question 8

How is salmonella transmitted?

Answer 8

Food, animals, processed food, unhygienic handling and processing of food products

Question 9

O antigen

Answer 9

Inhibits phagocyte killing

Question 10

Vi capsule antigen

Answer 10

Inhibits complement binding

Question 11

Flagellum

Answer 11

Motility

Question 12

H antigen

Answer 12

Adherence; inhibits phagocyte killing

Question 13

Entrotoxin

Answer 13

-Causes increase chloride permeability resulting in watery stool
- Attach to intestinal mucosa and invade M cells
- Multiplies intracellularly within membrane-bound vacuoles
- Host lyses and bacteria spreads

Question 14

Salmonella can infect:

Answer 14

• only humans
• some animals and humans
• no host preference

Question 15

What are the symptoms of salmonella?

Answer 15

Abdominal cramps, diarrhea, nausea, vomiting, chills, fever

Question 16

When does salmonella develop?

Answer 16

12-14 hours, persists 5 days

Question 17

Do microbes survive longer in wet or dry feces?

Answer 17

Up to 3 months in wet, up to 13 months in dry

Question 18

What is the best way to kill salmonella

Answer 18

Heat

Question 19

Where is salmonella an issue?

Answer 19

Globally

Question 20

Entroinvasive E. coli (EIEC)

Answer 20

Bloody diarrhae (dysentery), headache, fever, chills

Question 21

Entropathogenic E. coli (EPEC)

Answer 21

Colonize intestinal mucosa, forms attachment-effacing lesions which destorys microvilli
- mild to servere watery diarrhea

Question 22

Enterotoxigenic E. coli (ETEC)

Answer 22

Heat labile and/or heat stable entrotoxins
- watery diarrhea, no fever

Question 23

Entrohemorrhagic E. coli (EHEC)

Answer 23

Most common strain
- ingestion of <100 cells may produce disease
- Produces Shiga toxins and attachment-effacing lesions
- Onset abdominal cramps, watery diarrhea (often bloody), vomitting
- O157:H7 is atypical E. coli that is acid tolerant

Question 24

Camplobacter coli (C. coli)

Answer 24

Interactions with certain animals, which are reservoirs or the fecal-oral route
- Large number are asymptomatic, but can cause vomiting, abdominal pain, bloody diarrhea

Question 25

Campylobacteria coli can cause

Answer 25

Muscle weakness
- immune cells target myelin on axon
- neurons have a hard time sending signals