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Flashcards in Food and Water borne Deck (51)
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1
Q

5 Food and waterborne disease in Malaysia

A
Typhoid
• Cholera
• Food poisoning
• Dysentery
• Hepatitis A
2
Q

Bacteria species food

A
Salmonella spp, 
Shigella spp, 
Vibrio cholera,
Escherichia coli, 
Listeria monocytogenes, Clostridium
sp
3
Q

Fungi species food

A

Candida spp,

Sporothrix spp

4
Q

Virus species food

A

Hepatitis A, Adenovirus, Norovirus, Rotavirus

5
Q

Parasites species food

A

Entamoeba histolytica, Giardia

6
Q

Water-borne diseases:

A
  • Typhoid fever
  • Cholera
  • Hepatitis A
  • Leptospirosis
7
Q

Salmonella dose

A

Higher dose up to 10,000 -1,000,000 organisms per gram to cause infection

8
Q

Causes of salmonella

A

inadequate cooking, thawing
cross contamination
vectors

9
Q

Typhoid causative agent

A

salmonella typhi

10
Q

Why Typhoid still ongoing?

A
  • Healthy Carrier
  • Cases have not been clean-up
  • Personal Hygiene
  • Vaccination for food handler
  • Food Premises
  • Sanitation/Water supply
11
Q

Who are at

risk of typhoid (4)

A

Children
Travellers to endemic areas
Occupation related
Immunocompromised

12
Q

types of typhoid outbreak (4)

A

Sporadic -
involving only one or two persons in a household

Family outbreaks -
several members of the family are affected

Large outbreaks
caused by a widely distributed infective food item

Institutional outbreaks -caused by a contaminated single food item

13
Q

Typhoid incubation

A

2 weeks, but might vary between 3-28 days

14
Q

typhoid symptoms/ complications

A
  • Fever, headache, constipation, bradycardia
  • complication: intestinal perforation, chronic carrier

The abdominal symptoms are severe
Fever and illness may
continue for 4-6 weeks

15
Q

characteristics of a typhoid carrier

A

• Persistent positive stool culture for Salmonella
typhi for a year after the onset of acute typhoid
fever
• transmit infection to others
• Carrier state: 15% of patients, depending on age,
become chronic carriers harbouring S.typhi in the
gallbladder

16
Q

Management of Typhoid

A

Notification: Malaysian Act 342
• Hygienic control of food and water supplies
• Detection and treatment of chronic carriers
• Vaccination.

17
Q

cholera species that cause diarrhoea

A

 Inaba

 Ogawa

18
Q

dosage for infection, cholera

A

small

19
Q

method of action, cholera

A

multiplies in small intestine, makes toxins. isotonic fluid leaves into lumen of bowel

20
Q

symptoms of cholera

A
Rice-watery stool-severe
• Dehydration
• With/without vomiting
• Muscle cramps
• Hypovolemic shock
• Scanty urine
21
Q

management of cholera

A

Rehydration
• Monitor vital signs-blood pressure/pulse rate/urine output
• Antibiotic-for severe cases
• Proper sewage disposal/ good personal hygiene
• Proper cooking and hygienic handling of food
• Vaccination

22
Q

Dysentery causes

A

wht• Shigella spp
• Entamoeba histolytica
• Escherichia coli O157

23
Q

what is dysentery

A

blood mucus-rich diarrhoea

24
Q

Shigella spp- dose

A

low

25
Q

Shigella spp- lifespan

A

long term, in tap water 6 months, sea water 2-5 month

26
Q

Shigella shigellosis symptoms

A

Frequent passage of scanty amount of stools, mostly mixed with blood and mucus
• Moderate to high grade fever
• Severe abdominal cramps
• Tenesmus– pain around anus during defecation

27
Q

Shigella spp-diagnosis

A
Clinical
Microbiological investigations
• specimen: stool/blood
• test: Microscopic/macroscopic
• identification of bacteria: biochemical test
28
Q

Escherichia coli- food species

A

Enteropathogenic E. coli (EPEC),
Enterotoxigenic E. Coli (ETEC),
Enteroinvasive E. coli (EIEC)
Enterohemorrhagic E. coli (EHEC)

29
Q

Enterohemorrhagic E. coli- symptoms and duration; complications

A

hemorrhagic colitis: diarrhoea, abdominal pain, vomiting.
lasts for 4 - 8 days, may extend to 13 days.
Complications: bloody diarrhoea, acute ulcerative or ischemic colitis and sub-mucosal edema with severe
colonic inflammation

30
Q

What is special about E. coli O157:H7

A

heat sensitive but rsistant to freezing - cook your food

31
Q

what is hemolytic uremic syndrome (HUS)

A

E coli 0157 leading to acute renal failure, microangiopathic hemolytic anemia and thrombocytopenia

32
Q

Entamoeba histolytica cause, who does it affect, what’s different about it

A

cyst on hands
usually elderly chronic in nature
more mucus, less blood in stools; stools are very offensive and bulky

33
Q

Laboratory diagnosis -Entamoeba

A

Stool Examination:
Saline – motile trophozoites with ingested RBCs

Iodine – body stains yellow, nucleus with a central karyosome, brown glycogen mass

34
Q

Food poisoning symptoms

A

Acute onset of vomiting and / or diarrhoea and / or other symptoms
associated with ingestion of contaminated food.
neurological symptoms: motor weakness and cranial nerve palsies.

35
Q

food poisoning species

A

Staphylococcus aureus, Bacillus cereus, Listeria

monocytogenes, Clostridium spp

36
Q

Staphylococcus aureus bacteria type, growth range

A

non spore forming, gram negative
grows at a range temperature between 12-44C (optimum 37C)
pH range 4.0-9.83 (optimum 7.4-7.6)

37
Q

Symptoms, incubation of staph aureus

A

1-6 hours

nausea, headache, vomiting, diarrhoea

38
Q

Bacillus cereus mechanism, food and symptoms

A

Spore forming gram positive rods
consumption of enterotoxins
slow cooled rice, improper reheat

Fever, diarrhoea, vomiting

39
Q

Bacillus presentation

A

Good hygiene
Proper cooking of foods to destroy spores
Keep food at low temperature
Fast cooling of food

40
Q

Listeria monocytogenes features

A

Gram positive bacterium pathogenic to animals and human
Able to survive for many years in the cold in naturally infected sources
Faecal carriage 1-5% of healthy people
Trans-placental spread from mother to neonate

41
Q

Listeria symptoms

A

Abortion in pregnant women
Meningitis in newborn infants and immunocompromised adults.
Risk: Pregnant women, infants and elderly people.
Deaths have been reported in fetuses, neonates and other individuals with compromised health status.

42
Q

Clostridium perfringens features

A

spore-forming, anaerobic, gram positive bacillus
enterotoxin
Bacteria is found in the soil, dust, water, sewage marine sediments, decaying
cooling causes toxin growth, food cooked one day served the next

43
Q

Botulism features

A

Enterotoxins produced by Clostridium botulinum.
C. botulinum is an obligate, spore-forming anaerobe, and Gram positive bacilli
Neurotoxins, that are highly toxic, heat labile (inactivated by heating at 80oc for 10 min)
Unstable at alkaline pH, resistant to pepsin and acidic environment.
Resist the action of the gastric and intestinal juices.
Fucking lethal
incubation period: 12-72 H
Neuro symptoms
1-10 days duration

44
Q

fungal intoxication

A

from metabolites, mycotoxins, mproper drying before storage

45
Q

complications of food poisoning

A
  • Dehydration
  • Electrolyte imbalances
  • Tetany
  • Convulsions
  • Hypoglycemia
  • Renal failure
46
Q

Viral food borne infections features

A

acid resistant, attacks certain lining cells in GIT to replicate, High virus content in fecal matter

47
Q

Hep A

A

30 day incubation

long lasting

48
Q

rotavirus

A

green shit, gradual onset, kids 1-2, fever

49
Q

general investigation of FBD

A
Stool microscopy &Stool cultures
Blood cultures
ELISA for rotavirus
Immunoassays, bioassays or DNA probe tests to identify E. coli strains
Detection of toxins
50
Q

management of FBD

A
Symptomatic treatment
• Rehydration
• Antipyretic
• Anti-emetic
• Antibiotic for severe cases
51
Q

vaccines

A

Vaccine is available for
• Typhoid
• Cholera
• Hepatitis A