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FST3108 - Food safety and regulation > W10 : Parasites > Flashcards

W10 : Parasites Flashcards

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1
Q

Core concepts

What are the different types of hosts for parasites? [4]

A
  1. Intermediate host
  2. Definitive (final) host
  3. Accidental host
  4. Incidental (dead-end) host.
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2
Q

Core concepts

What is an intermediate host?

A

An organism in which a parasite undergoes development or an asexual phase but does not reach sexual maturity. It supports the immature or non-reproductive forms of the parasite.

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3
Q

Core concepts

What is a definitive host?

A

The organism in which a parasite reaches maturity and undergoes sexual reproduction.

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4
Q

Core concepts

What is an accidental host?

A

A host in which the parasite does not typically live, but it can still harbor the parasite. The parasite usually fails to fully develop or reproduce but can cause symptoms, tissue damage, or immune responses.

<br></br><br></br>

  • Because conditions for development and reproduction are suboptimal, they tend to move all around the body to find a good place to survive
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5
Q

Core concepts

What is an incidental (dead-end) host?

A

A host that shelters the parasite, but the parasite cannot be transmitted to other hosts, preventing the parasite from completing its life cycle.

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6
Q

Core concepts

What is an oocyst?

A

A cyst (infectious form of the parasite) containing a zygote (egg) formed by a parasitic protozoan. It is an immature, “resting” stage that sporulates in 5-12 days outside the body (in external environment) to become infectious.

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7
Q

Types of parasites

Name the 4 main categories of parasites relevant to food safety.

A
  1. Tapeworms (cestodes)
  2. Roundworms (nematodes)
  3. flukes (trematodes)
  4. protozoa
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8
Q

Types of parasites

Name the 4 main categories of parasites relevant to food safety.

A
  1. Tapeworms (cestodes)
  2. Roundworms (nematodes)
  3. flukes (trematodes)
  4. protozoa
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9
Q

Types of parasites : tapeworms

How do tapeworms develop in the human body?

A

Humans ingest larvae of tapeworms from food sources like meat. Tapeworms have both female and male reproductive organs in 1 worm, and start maturing (full development) and reproducing in the GI tract.

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10
Q

Types of parasites : tapeworms

After entering the body, how do tapeworms cause illness in humans? What common symptoms do they cause?

A

Tapeworms reproduce and mature in the small intestines, and attach to intestinal walls. They can grow up to several metres long, absorbing nutrients and potentially causing weight loss, abdominal pain and digestive disturbances.
<br></br>
- Also, passing of proglottoids (segments of tapeworm, reproductive structure) in feces, which may contain eggs.

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11
Q

Types of parasites : tapeworms

In adults, most tapeworm infections show symptoms. True or false?

A

False. Most cases are asymptomatic

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12
Q

Types of parasites : tapeworms

What are the names for:
1. Beef tapeworm
2. Pork tapeworm

A
  1. Taenia saginata (beef tapeworm)
  2. Taenia solium (pork tapeworm)
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13
Q

Types of parasites : tapeworms

Who are the final / definite hosts for Taenia Solium?

A

Humans

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14
Q

Types of parasites : tapeworms

In the case of Taenia Solium infection, what is the characteristic disease that may form?

A

Human cysticerosis
- Humans are accidental hosts, T.solium does not usually infect humans (usually pigs)
- So T.solium tapeworms will go all over the human body to find a suitable living area –> formation of cysts in varioys parts of the body –> causing symptoms including seizures

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15
Q

Types of parasites : tapeworms

Human Cysticerosis can result from T solium. What are the 2 modes of transmission?

A

1) Consumption of food or water contaminated with eggs of T solium. Eggs hatch and larvae migrate to various parts of body to form cysts.

<br></br><br></br>
2) Some people with intestinal tapeworms infect themselves with eggs from their own feces due to poor personal hygiene. (can be transmitted from human to human to cause cysticercosis where eggs are ingested;; but rare. Usually person infect themselves)

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16
Q

Types of parasites : tapeworms

How long does it takes for symptoms of human cysticercosis to appear?

A

Weeks to years after infection

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17
Q

Types of parasites : tapeworms

How to diagnose Taeniasis?

A

Microscopic examination of eggs / proglottids in feces.
<br></br><br></br>
Note : extreme care must be taken in processing samples!! Ingesting eggs can lead to cycsticerosis

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18
Q

Types of parasites : tapeworms

How to treat Taeniasis?

A

Drugs
1. Praziquantel
2. Albendazole

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19
Q

Praziquantel and albendazole are common drugs in treating parasite infections. How do they work?

A

Praziquantel : causing severe spasms and paralysis of the worms’ muscles.
<br></br><br></br>
Albendazole : prevents worm from absorbing sugar (glucose), causing it to lose energy and die

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20
Q

Types of parasites : tapeworms

What is the name of the largest human tapeworm?

A

Diphyllobothrium latum (fish tapeworm)

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21
Q

Types of parasites : tapeworms

Who are the :
1. Intermediate hosts
2. final / definite hosts for Diphyllobothrium latum?

A
  1. Fish (intermediate host)
  2. Fish-eating mammals (incl human) and birds (final host)
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22
Q

Types of parasites : tapeworms

Diphyllbothrium latum causes an illness called diphyllobothriasis. In which parts of the world does diphyllobothriasis occur?

A

Europe, N America , Asia where lakes and rivers co-exist.

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23
Q

Types of parasites : tapeworms

How long does the infection from Diphyllobothrium latum last?

A

Very long lasting.

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24
Q

Types of parasites : tapeworms

What are the characteristic symptoms of Diphyllobothriasis? [3]

A

1) Vitamin B12 deficiency and anemia in heavy / prolonged infestation.
<br></br>
Migration of proglottids can cause:
2) cholecystitis : inflammation of gallbladder
3) cholangitis : inflammation of bile ducts

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25
Q

Types of parasites : tapeworms

How to diagnose Diphyllobothrium latum?

A

Microscopic examination of eggs on stool sample

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26
Q

Types of parasites : tapeworms

What are the 2 effective drugs for killing Diphyllobothrium latum?

A

Praziquantel
Niclosamide

Worms can survive > 25 years in intestine, need effective drugs

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27
Q

Types of parasites : tapeworms

How to prevent Diphyllobothrium lactim?

A

Do not eat raw / undercooked fish dishes.

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28
Q

Types of parasites : roundworms

How do roundworms grow in the human body?

intestinal phase

A

Through ingestion of eggs or larvae. When roundworms mature and grow out of larvae, they can multiply by sexually reproducing with each other in the GI tract. (intestinal phase)

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29
Q

Types of parasites : roundworms

After the roundworm develops into an adult in the intestine (i.e. after the intestinal phase), what happens next and what kinds of symptoms do roundworms cause?

A

Roundworms usually migrate out of the small intestine into other organs like muscle, eyes, and can even impact the **central nervous system. **
- This causes symptoms such as muscle aches, joint pain, eye swelling.

bc human are incidental / accidental hosts, worm dont usually survive in human body. so worm want to migrate out of intestine to find more suitable conditions to survive.

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30
Q

Types of parasites : roundworms

For roundworms, Anisakis and Trichinella Spiralis, humans serve as the final / definitive host. True or False?

A

False. For Anisakis, marine animals are the definitive hosts where L3 larvae develop into adults (but humans usually consume the larvae). For Trichinella Spiralis, pigs / wild animals like bears are the definitive hosts.

<br></br><br></br>
In both cases, humans are accidental and dead-end hosts.
- Accidental/incidental : roundworms usually don’t reside in humans
- Dead end hosts : The larvae cannot fully develop and reach sexual maturity, usually die within 3 weeks after infection

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31
Q

Types of parasites : roundworms

Infection by Anisakis is caused by consumption of what kind of food?

A

Seafood : ocean fish and cephalopods (cod, pacific salmon, squid etc)

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32
Q

Types of parasites : roundworms

What are the symptoms of Anisakiasis (infection by Anisakis)? [3 = 1 common + 2 characteristic symptoms]

A

Acute abdominal pain
<br></br><br></br>
Characteristic symptoms
- tingling / tickling sensation in throat and coughs up the roundworm (nematode)
- may provoke life-threatening allergic reactions as larval nematodes burrow (hide) into gastric mucosa (stomach lining)

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33
Q

Types of parasites : roundworms

How long does it take for symptoms of Anisakiasis to show?

A

1 hour to 2 weeks after consuming seafood.

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34
Q

Types of parasites : roundworms

How to diagnose Anisakiasis? [2]

A
  1. Conduct a morphological exam of worms coughed up
  2. Endoscopic exam and extraction of worm from stomach
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35
Q

Types of parasites : roundworms

How to treat Anisakasis, under less severe and more severe conditions?

A

For less severe cases, anthelmintic drugs have been used with some success, but the worm will die and get passed out of body eventually.

<br></br><br></br>
For more severe pain, endoscopic removal is the best treatment.

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36
Q

Types of parasites : roundworms

How to prevent Anisakiasis? [3]

A
  1. Sufficient cooking to inactivate worms
  2. Freezing and cooking to kill Anisakis Simplex (the larvae/baby version of the worm)
  3. Do not eat raw / undercooked fish and squid
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37
Q

Types of parasites : roundworms

Since freezing and cooking seafood can kill A Simplex, consumers are fully protected against allergic reactions. True or False?

A

False. Though the worms are dead, consumers can still get allergic reactions from the ingested A. Simplex antigens

38
Q

Types of parasites : roundworms

A
39
Q

Types of parasites : roundworms

In the life cycle of Trichinella spiralis, how does Trichinellosis pass on from animal to animal?

A

Trichnellosis can only pass on from one animal to another animal only if an animal eats an infected animal (predation / cannibalism).

40
Q

Types of parasites : roundworms

Trichinella spiralis can be transmitted through the domestic cycle (domesticated animals) and the sylvatic cycle (wild animals). Which cycle Trichinella more associated with and why?

A

Sylvatic cycle, as animals can prey on and scavenge infected wild animals.

<br></br><br></br>
Whereas in domestic cycle, pigs get infected through contaminated feed. However, with better farming practices and proper farming system, it rarely occurs in the domestic cycle.

41
Q

Types of parasites : roundworms

Consumption of what kind of food is associated with Trichinellosis?

A

Raw / undercooked pork or wild game (wild game : meat from an animal that is typically found in the wild, non domesticated)

42
Q

Types of parasites : roundworms

Is Trichiellosis usually spread from person to person?

A

No, human are dead-end hosts and its not through fecal oral route so

43
Q

Types of parasites : roundworms

An infected person with Trichinellosis always shows symptoms. True or False?

A

False. In the case of light infection, humans could be asymptomatic

44
Q

Types of parasites : roundworms

What are some symptoms of Trichinellosis? Also state how long after consuming contaminated meat before these symptoms show (intestinal phase and later phase) [2]

A

Intestinal invasion (1-2 days after eating contaminated meat) : Nausea, vomiting, diarrhea, abdominal pain.
<br></br><br></br>
Characteristic symptoms
1 week after infection, when larvae migrate into muscle tissues : eye swelling, Conjunctvitis (pink eye), aching muscles and joints

45
Q

Types of parasites : roundworms

After migrating to muscles, larvae of Trichinella spiralis form cysts. What are cysts, and what symptoms can larval encystment in muscles cause?

A

Cysts are clusters of larvae enclosed in a protective wall, so that larvae can survive harsh conditions.
<br></br>

Larvae encystment causes myalagia (ache and pain) and weakness, and symptoms eventually subside.

46
Q

Types of parasites : roundworms

How to diagnose trichinellosis? (initial diagnosis and confirmation)

A
  • Initial diagnosis relies on classic symptoms : eye swelling, muscle inflammation and fever
  • Confirmation by eosinophilia / positive test for antibody / muscle biopsy for T spiralise

Eosinophilia happens when your body produces too many eosinophils. Eosinophils are one of several white blood cells that support your immune system. (Could occur due to allergic reactions / ingestion of parasite etc)

47
Q

Types of parasites : roundworms

How to treat Trichinellosis? [3]

A
  • Anthelmintic albendazole is effective in elimnating intestinal worms and larvae
  • Muscle aches : pain relivers
  • To control inflammation during larval migration : corticosteriod
48
Q

Types of parasites : roundworms

How to prevent Trichinellosis? [3]

A
  1. Avoid undercooked pork and game meat
  2. Deep freeze meat for 3 weeks to kill trichinella (note : does not work in bear meat)
  3. Cook meat thoroughly

Temperature + avoid

49
Q

Types of parasites : flukes

Liver flukes are transmitted to humans through the oral faecal route. True or False?

A

True

50
Q

Types of parasites : flukes

Since the life cycle of flukes involves the oral faecal route, it is considered a person to person infection. True or false?

A

False, bc the eggs that is passed in human faeces into water bodies needs to go through an intermediate host, snails, before it develops into cercariae (larvae), and larvae goes into skin / flesh of animals. Since only the larvae is infectious to humans, it means that it is indirect infection from animal to human.

If directly ingesting eggs causes liver fluke infection, it would then be considered a human to human transmission. But in this case, its not since eggs need to develop in intermediate host first before it can be infectious.

51
Q

Types of parasites : liver flukes

What is another name for Clonorhis sinensis ?

A

Chinese / oriental liver fluke

52
Q

Types of parasites : liver flukes

What is another name for Clonorhis sinensis ?

A

Chinese / oriental liver fluke

53
Q

Types of parasites : liver flukes

What are the symptoms of Clonorchiasis? [3 – general symptoms (2), acute phase (5) and long-term infections (4)]

A
  • General symptoms : inflammation and intermitten obstruction of biliary ducts
  • Acute phase : fever, abdominal pain, nausea, mild jaundice, hepatomegaly (enlarged liver)
  • Long-standing infections : cholangitis (bile dict inflammation), cholelithiasis (gallstones in gall bladder / bile duct), cholangiocarcinoma (bile duct cancer), pancreatitis ( pancrea inflammation)
54
Q

Types of parasites : liver flukes

What is another name for Opisthorchis viverrini and why is it so significant?

A

Southeast Asian liver fluke.
- it affects millions of people in SEA (South East Asia), including Laos, Thailand, Vietnam
- Cholangocarcinoma (bile duct cancer) caused by Opisthorchis viverrni kills 20,000 Thais a year !!!

55
Q

Types of parasites : liver flukes

For Opisthorchiasis (caused by Opisthorchis viverrini), most infections show symptoms. True or False?

A

False. Most cases are asymptomatic.

56
Q

Types of parasites : liver flukes

What are symptoms of Opisthorchiasis in mild cases [3] and severe cases [5]?

A
  • Mild cases : abdominal pain, diarrhea / constipation, dyspepsia (burning, pain, or discomfort in the digestive tract)
    <br></br><br></br>
    Severe cases :
    1. enlargement, obstruction & fibrosis of the liver
    2. Jaundice
    3. Cholangitis (bile duct inflammation)
    4. Cholangiocarcinoma (bile duct cancer)
    5. Cholecystitis (gall bladder inflammation)
57
Q

Types of parasites : liver flukes

How to diagnose liver flukes? [2]

A
  1. Microscopic identification of eggs in stool sample.
  2. Endoscopy examination of small intestine for eggs
58
Q

Types of parasites : liver flukes

How to treat liver flukes? [2]

A
  1. Drugs : Praziquantel or albendazole
  2. In the case of biliary obstruction (blockage in the bile duct system) : surgery may be required
59
Q

Types of parasites : liver flukes

How to prevent liver flukes? [3]

A
  1. Do not eat raw or undercooked fish
  2. Cook fish to internal temp > 63°C
  3. Freeze fish at -20°C or below for 7 days OR at -35°C or below for 15 hours
60
Q

Types of parasites : liver flukes

What are some control strategies to slow down the spread of liver flukes?

A
  1. Stool exams and treatment of positive cases with Praziquantel → eliminate human host reservoir
  2. Promote eating of cooked fish to prevent infection (but may be hard to change tradition)
  3. Improve hygienic defecation to interrupt disease transmission → in some countries, ppl may j shit into nearby ponds etc.
61
Q

Types of parasites : protozoa

What is meant by an “oocyst” in protozan parasites?

A

It is a resting stage, a dormant and non-infectious form.

62
Q

Types of parasites : protozoa

What process do oocysts undergo to become infectious to humans?

Oocysts are non-infectious when first passed out of the body in the faeces

A

Oocysts undergo sporulation, which occurs for around 5-12 days in the external environment, outside of the human’s body.

63
Q

Types of parasites : protozoa

Cyclosporiasis is a disease caused by (name of protozoan parasite) ??

A

Cyclospora cayetanensis

64
Q

Types of parasites : protozoa

Cyclosporiasis affects both humans and animals. True or False?

A

False. Humans are the only known hosts (definitive hosts).

65
Q

Types of parasites : protozoa

Cyclosporiasis is a direct human to human tranmission. True or false?

A

False, because ingestion of oocysts shedded in faeces will not directly lead to infection. The oocysts needs to sporulate in the environment first before it can be infectious. Thus, it is an indirect human - human transmission

66
Q

Types of parasites : protozoa

What are symptoms in cyclosporiasis? (Less severe (2 main points) and more severe cases(1 main point) )

A

Less severe cases:
- Some people are asymptomatic
- Symptoms linked to intestinal disturbance : Diarrhoea (sometimes explosive), loss of appetite, weight loss, nausea and tiredness

<br></br><br></br>
More severe cases:
- Flu-like symptoms : headache, vomiting, fever, aching

67
Q

Types of parasites : protozoa

What is the incubation period of cyclosporia cayetanensis? And how long does infection last?

A

Incubation period : 7 - 10 days

<br></br><br></br>
Infection period : days to months, may go away and come back

68
Q

Types of parasites : protozoa

Which groups of people are at higher risk of cyclosporiasis?

A

Young, old (Elderly), immunocompromised

YOPI without the P (pregnant)

69
Q

Types of parasites : protozoa

What kinds of foods are associated with cyclosporiasis? [2]

A
  1. Direct consumption of contaminated water.
  2. Fruits and vegetables that have been irrigated with contaminated water.
70
Q

Types of parasites : protozoa

How to diagnose cyclosporasis?

A

Idetification of unsporulated oocysts in stool specime by light / UV microscopy.

71
Q

Types of parasites : protozoa

How to treat cyclosporiasis? [3]

A
  1. Antibiotic combination of Trimethoprim and sulfamethoxazole (bactrim, septrim)
  2. Supportive treatment of fluid
  3. Electrolyte balance and rest

Points 2 and 3 : to make up for the electrolyte and fluid loss during diarrhea

72
Q

Types of parasites : protozoa

How to prevent cyclosporiasis? [4]

A
  1. Avoid food and water contaminated with faeces
  2. Eat fresh fruits and vegetables from safe sources
  3. Wash fruit and vegetables thoroughly
    - Note : washing does not kill and remove cyclospora cayetanensis
  4. Boil water and cook food to destroy oocysts
73
Q

Types of parasites : protozoa

How does Cryptospordium parvum transmit and get into the human body? (What route? Animal to human or? )

A

Indirectly from human to human through the oral faecal route.
- Oocyst (unsporulated) in faeces of human, which can get into water bodies, which then sporulate in water and contaminated water consumed by human.

74
Q

Types of parasites : protozoa

What foods / activites are mainly associated with cryptosporidium parvum (the source of contamination) [2]? What other foods may be implicated? [3]

A

1) Consumption of contaminated drinking water
2) Accidentally gulping down contaminated recreational water (in swimming pools) → nasty kids shitting into pool tsktsk

[because contaminated water may be used for irrigation, or used during processing etc]:
3) Fruits and vegetables
4) Raw milk, sausages and offal (as cattle are also major hosts)
5) Wet / moist foods

75
Q

Types of parasites : protozoa

What are symptoms of crytosporidium parvum? [2]

A
  1. Some are asymptomatic
  2. Mild to profuse diarrhea (3-6 litres of watery stool per day), nausea, vomiting, dehydration, fever & malaise (weakness)
76
Q

Types of parasites : protozoa

Which groups of people are at higher risk of severe illness caused by cryptosporidum parvum?

A

Young, old (Elderly), immunocompromised

YOPI without the P (preg)

77
Q

Types of parasites : protozoa

What are characteristic symptoms caused by cryptosporidium parvum in immunodeficient people?

A
  1. Prone to extraintestinal cryptosporidiosis (outside of intestine) involving :
    a. bile duct
    b. lungs
    c. middle ear

<br></br><br></br>
- Disease in some immunocompromised people become chronic, and could be life-threatening. ‼️

In healthy person, it stays within intestine and recover in a week but in immunocompromised people, it can travel out of the intestine

78
Q

Types of parasites : protozoa

What is the incubation period and infection duration for cryptosporidium parvum?

A
  • Incubation period : 7 - 10 days
  • Infection duration : 2-14 days in healthy people, and diarrhea lasts for months in immunocompromised people.
79
Q

Types of parasites : protozoa

How to diagnose infection caused by Cryptosporidium parvum? [2]

A
  1. Identification of oocysts in stool specimen by light microscopy
  2. Acid-fast / specific fluorescent antibody stains
80
Q

Types of parasites : protozoa

How to treat Cryptospordium parvum infection?

A

Drugs
1) Nitazoxanide (Alinia)
2) Azithromycin (Zithromax)
1 and 2 : to control Cryptosporidium
<br></br><br></br>

3) Loperamide (imodium) → regulates gut motility ; fluid and electrolyte replacement (for diarrhea)

81
Q

Types of parasites : protozoa

Toxoplasma gondii infection is zoonotic. True or False?

A

True, it is transmitted from animal (cat) to human.

82
Q

Types of parasites : protozoa

In what 2 ways can Toxoplasma gondii transmitted?

A

1) Direct transmission : from cats (pets) to humans
- through oocysts in faeces + humans never wash their hands properly
- indirect contamination, when allowing pets into kitchen
- cats may shit in the garden, and some people may plant their own produce at home → contaminated soil contaminate the produce
<br></br><br></br>
2) Indirect transmission : from wild cat → pigs → humans (by consumption of pork)

83
Q

Types of parasites : protozoa

Who is the
1. definitive host
2. intermediate host
3. dead-end / accidental host

For toxoplasma gondii?

A
  1. Feline species (cats)
  2. Pigs
  3. Humans
84
Q

Types of parasites : protozoa

What are 2 other unique routes of transmission of toxoplasma gondii infection?

A
  1. **From mother to foetus **: of a mother is infected with T gondii during / shortly before preganact, tachyzoites (rapidly multiplying stage) can infect fetus
  2. During organ transplants / blood transfusion (rare)
85
Q

Types of parasites : protozoa

Toxoplasmosis is harmless to most people. True or False?

A

True, most people are asymptomatic.

86
Q

Types of parasites : protozoa

Which 3 groups of people can get severe toxoplasmosis?

A
  1. Immunocompromised infection (those with HIV / AIDS infection)
  2. Organ transplant recipients
  3. Infants (transmission from mom to baby)
87
Q

Types of parasites : protozoa

What is the consequence of severe toxoplasmosis :
1. generally
2. in infants

A
  1. Damage in eyes / brain
  2. Infants infected before birth can be born retarded or with other mental / physical problems
88
Q

Types of parasites : protozoa

How to diagnose toxoplasmosis? [2]

A

1) Serological tests : immuniglobulin G (igG), an antibody for determining infection ;; igM to estimate time of infection

<br></br><br></br>
2) Direct observation / isolation of parasite in tissue, blood or other biopsy material

  1. IgM Antibodies:
    Early Infection (Acute Phase):
    IgM is the first antibody produced by the immune system after an infection.
    In toxoplasmosis, IgM levels usually rise within 1-2 weeks of infection and peak during the acute phase.
    Decline:
    IgM levels begin to decline after the acute phase, typically becoming undetectable within a few months.
    In some cases, IgM can persist for longer periods (months to over a year), which can complicate interpretation.
  2. The levels of IgG and IgM antibodies in a person infected with Toxoplasma gondii depend on the stage of infection. Here’s how they typically behave:
  3. IgM Antibodies:
    Early Infection (Acute Phase):
    IgM is the first antibody produced by the immune system after an infection.
    In toxoplasmosis, IgM levels usually rise within 1-2 weeks of infection and peak during the acute phase.
    Decline:
    IgM levels begin to decline after the acute phase, typically becoming undetectable within a few months.
    In some cases, IgM can persist for longer periods (months to over a year), which can complicate interpretation.
    <br></br><br></br>
  4. IgG Antibodies:
    Later Infection (Chronic Phase):
    IgG antibodies are produced later in the infection, usually within 1-2 weeks after the initial IgM response.
    IgG levels rise during the acute phase and remain elevated for life, indicating prior exposure or infection.
    High IgG levels with low or absent IgM typically indicate a past infection rather than a recent one.
89
Q

Types of parasites : protozoa

How to treat toxoplasmosis?

A

Sulfadiazine (antibiotic), used together with Daraprim (folic acid antagonist → substance that interferes with the function of folic acid, preventing cells from using it to synthesize DNA, effectively blocking cell division and often used as a medication to treat cancer or certain inflammatory conditions)

90
Q

Types of parasites : protozoa

How to prevent toxoplasmosis? [5]

A
  1. Cook food to safe temperatures (meat > 71°C; poultry > 74°C)
  2. Peel / wash fruits and vegetables thoroughly before eating
  3. Wash cutting boards, dishes, counters, utensils and hands with hot soapy water after contact with raw meat, poultry, seafood, or unwashed fruits/vegetables.
  4. Wear gloves during any contact with soil / sand and then wash hands with soap
  5. Feed cats with only canned and dried commercial food / well-cooked food, do not serve raw or undercooked meats.

FST3108 - Food safety and regulation (8 decks)

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