Lecture 9

Question 1

What class, phylum and species do campylobacter come from?

Answer 1

Phylum: Epilison Proteobacterium
Class: Proteobacteria
Species: C. jejunum and C. coli

Question 2

Describe their shape and struc.

Answer 2

Shape: S, spiral or curved shaped. Structure: Contain two flagellum for colonization and is gram negative.

Question 3

What conditions do they best grow under
Acidity:
Temperature:
O2 level

Answer 3

Acidity: Low acid conditions
Temperature: 30 degrees celsius or above
O2 level: Microaerophillic, and grow in low o2 conditions

Question 4

what are antacids and how are they dangerous to people?

Answer 4

Antacids: cause the pH of the stomach do bacome more basic allowing for some campylobacter to survive.

Question 5

What is the three ways you can kill campylobacter in food and water?

Answer 5

1. Heat and radiation of cooked food
2. Chemicals to treat untreated water
3. Freeze at 20 degrees celsius( however some may go into VNBC state and survive)

Question 6

What human secretory and farm fluids can campylobacter survive in for up to 5 weeks?

Answer 6

1. Animal feces
2. Urine
3. Milk
4. Water

Question 7

what are the sources or resovioirs for camyplobacter?

Answer 7

1. Poultry
2. Raw Milk
3. Surface water
4. Rodents and farm animals
5. Ameobe (act as protective host for pathogen)
6. Domestic pets such as cats and dogs
7. Water not treated with chemicals

Question 8

How many people are infected by campylobacteria each year?

Answer 8

1.5 million

15-15 million in developing countries

Question 9

Why are do some people express sympotoms of campylobacteria while others don’t

Answer 9

Depends upon personal immune system or gut microbiota

Question 10

How is campylobacteria diagnosed?

Answer 10

1. Feces of person contains blood, pus, or mucus

2. Person is nauseous, has fever and stomach cramps

Question 11

what are the symptoms and how long does it take for the symptoms of the illness to kick in and how long does it last(Campylobacteriosis)?

Answer 11

2-5 days and last for a week

Question 12

What post infection complications can campylobacteriosis lead to?

Answer 12

1. reiter syndrome
2. inflammotory bowl syndrome
3. gullian barre syndrome

Question 13

why are antibiotics not the best treatment for campylobacteriosis? What are the exeptions and which antibiotic is preffered for such and why?

Answer 13

Antibitoics only reduce length of illness for one day so they are only prescribed for people with other illnesses and if it will lead to serious illness.

Question 14

What are most common sources of salmonella outbreaks?

Answer 14

Food source outbreaks from most common to least common:

1) poultry-29%
2) vegetables, seafood, oil, sugar and dairy-20%
3) eggs-18%
4) vegetables grown on a vine, fruits and nuts-13%
5) Pork: 12%
6) Beef: 8%

Causes
Mainly caused by the transfer of pathogens from animal feces to produce, meat and people. This occus as a result of transovarian to egg shell transmission, animal factory farming and reuse of animal products in slaughterhouses

S.enterica (nontyphoid) is responsible for 99 % of outbreaks

Question 15

What are some ways of preventing the spread of salmonella in the food industry?

Answer 15

1) Instilling HACCP plans that food production must comply with in all companies
2) Washing meat and produce even if outer skin has been peeled.

Question 16

How prevalent is salmonella?

Answer 16

1) It is the leading cause of foodbourne disease world wide
2) It is the second common cause of gasterointestinal disease after camplobacteria
3) In the US:
1.35 million infections
26000 hospitalizations
420 deaths per year

Question 17

What is the infective dose of salmonella?

Answer 17

1-10 cells can cause infection, the fattier a food is the lower the number of cells that are required to cause an infection. The reason for this is because fat protects the cells from gastric acids allowing them to pass through the GI tract

Question 18

What are the symptoms of non-typhoidal salmonella? How long does it take for the symptoms to kick in and how long do they last?

Answer 18

1) nausea
2) fever
3) vomiting
4) diareah (may be bloody)

Symptoms:

• 2-7 days to kick in
• usually lasts 8-72 hours
• does not rquire treatment unless patients are immunococmpromised or are children less then 5

Question 19

What post-infectious disorders result from non-typhoidal salmonellosis

Answer 19

1) Anlyosing spondylitis
2) Reiters syndrome
- both are autoimmune disorders

Question 20

Treatment approaches

Answer 20

1) alternative to antibiotics:
- plant extracts
- probiotics and prebiotics
- bacteriophages
- vaccines
- bacteriocins
2) Antibiotics
- 46 percent are resistant to multiple drugs
- 100,000 drug resistant cases each year

Question 21

What barriers must salmonella cells get past and what are some mechanisms to overcome this

Answer 21

Some barriers include:

1) antimicrobial enzymes in saliva and stomach acid.
2) Stomach acid
- Cells protect themselves by acitivating an acid tolerance response&raquo_space;» makes salmonella cells have a more basic pH on their insides than rest of stomach environment, protecting them from acid
3) mucus released from intestinal cells(may contain antimicrobial peptides)
4) Intestinal peristalliss-wavelike movments which push food downwards
5) shedding and of intestinal cells- prevent colonization of bacteria»>salmonella cells are pushed out from on top
6) must also compete with other microbes to attach to intestinal cells

Question 22

What are the steps bacteria must take to go through pathogenisis?

Answer 22

1) Can enter peyers patches
- m cells in epilitheum
- absorbed by dendrites and macrophages
2) Then spread through the GI system, are taken up by phagocytes (dendrites and macrophages?) that move through the mesenteric lymph nodes and travel to the spleen and liver
3) Once vacoules in cells are infected by pathogen it moves from the top to side of cell and releases pathogens to move througout the body and are consumed by more cells