Infection 1: Introduction to infection Flashcards
1
Q
What are the organisms that cause infection
A
- Helminths (Biggest)
|
- Insects |
|
- Protozoa |
|
- Fungi |
|
- Bacteria |
|
- Viruses |
|
- Prions (Smallest)
2
Q
Example of helminths
A
Tapeworm
3
Q
Example of insects
A
Fleas
4
Q
Example of Protozoa
A
Malaria
5
Q
Example of fungi
A
Candida
6
Q
Example of bacteria
A
Staphylococci
7
Q
Example of virus
A
Influenza
8
Q
Example of prions
A
Kuru
9
Q
What are the most common infections
A
Bacterial and viral
10
Q
What is a parasite
A
Organism which depends on another for its survival to the detriment of the host
11
Q
What are traditional medical parasites
A
- Helminths
- Insects
- Protozoa
12
Q
Where do endoparasites live
A
Inside body
13
Q
Where do ectoparasites live
A
Outside body
14
Q
What are the major illnesses that endoparasites cause
A
- Helminths
- Protozoa
15
Q
What are the minor illnesses that ectoparasites cause
A
- Fleas
- Lice
- Bed bugs
- Ticks
16
Q
Describe Protozoa
A
- unicellular
- too small for naked eye
- complex lifecycle, involves more than 1 host
17
Q
What are the two types of Protozoa
A
- Amoebae
- Sporozoa
18
Q
Give an example of sporozoa
A
Plasmodium falciparum
19
Q
Give an example of amoebae
A
Entamoeba histolytica
20
Q
What does entamoeba histolytica do
A
- invades large bowel lining
- causes dysentery
21
Q
What are the symptoms of dysentery
A
- abdominal cramps
- bloody diarrhoea
22
Q
How is entamoeba excreted and spread and what increase its risk
A
With faeces
Contaminated food & water
Poor hygiene
23
Q
Give an example of sporozoa
A
Plasmodium falciparum
24
Q
Where does plasmodium falciparum live and what does it infect
A
Lives in humans and mosquitoes
Infects red blood cells & liver
25
What a re the symptoms of malaria
- Fever
- Headache
- Joint pains
26
What a re the complications of malaria
- Kidney failure
- Coma
- Brain problems
- Death
27
What is the risk of malaria
Geographical
28
Describe helminths
- complex organisms
| - some complex life cycles with more than one host
29
How many types of worms are there
- Cestodes
- Trematodes
- Nematodes
30
Describe cestodes
- segmented
| - flat
31
Describe trematodes
- unsegmented
| - flat
32
Describe nematodes
- cylindrical
| - digestive tract with lips, teeth and anus
33
Give an example of cestodes (tapeworms)
Toenia saginata
34
Describe toenia saginata
- intestinal parasite of humans
- tiny cysts on beef meat
- ingested by humans
35
Heat are the symptoms of toenia saginata
Largely asymptomatic
- abdominal pain
- malnutrition
36
What is the diagnosis foe toenia saginata
- Patience
| - Stool microscopy for eggs
37
Who is the obligatory host for toenia saginata
| Who is the intermediate
Human
Cattle
38
Give an example of trematodes (flukes)
Schistosomia haematobium
39
What does schistosomia haematobium cause
- Infection of veins around bladder
- Bladder inflammation
- Bleeding into urine
40
Diagnosis for schistosomia haematobium
Urine microscopy for eggs
41
Intermediate host for schistosomia haematobium
Freshwater snail
42
Give an example of ectoparasites
Bedbug
43
Example of bedbug
Cimex lectulsrius
44
Symptoms of bedbug
- Itchy rash after bite
| - can transmit other infections
45
What are the forms of fungal infections
- Yeasts: single cells which bud
| - Moulds: filamentous strands
46
What are superficial fungal infections
- Tinea pedis (athlete’s foot)
| - Tinea corporis (ringworm)
47
Give an example of severe invasive fungal infection
Cryptococcus neoformans
48
What does cryptococcus neoformans do
Infect patients with failing immune system —> low resistance
49
What does cryptococcus neoformans cause
- meningitis
- headache
- neck stiffness
- confusion
- coma
- death
50
What diseases is bacteria responsible for
- Pneumonia
- UTI
- Meningitis
- Cellulitis (skint and subcutaneous tissue infection)
- Cholecystitis (gall bladder infection)
- Diverticulitis (bowel infection)
- Appendicitis
51
What shapes do bacteria take
- Round (coccus)
- Rod (Bacillus)
- Grouping (clusters, chains apirs)
52
How do some bacteria differ in structural composition
Some retain violet crystal stain
53
Gram positive colour
Purple
54
Gram negative colour
Pink (can’t hold stain)
55
Give an example of bacterial infection
Streptococcus pneumonia
56
Describe appearance of streptococcus pneumonia
- gram-positive
| - diplococci
57
What does streptococcus do
- colonise nose & throat
| - invades lungs —> pneumonia
58
What are symptoms of streptococcus
- cough
- dirty septum
- chest pain
- breathlessness
- fever
- blood stream infection
- meningitis
- death
59
What are the different kinds of viral infections
- Acute
- Chronic
- Latent
60
What happens in acute viral infection
- norovirus infects host for days
| - diarrhoea & vomiting
61
What happens in chronic viral infection
- hep C —> liver inflammation for years
62
What happens in latent viral infection
Herpes dormant for decades —> activated —> causes disease
63
Example of virus that can cause latent infections
Varicella zoster
64
Varicella zoster virus causes
Chickenpox
65
Characteristics of chickenpox
- rash
| - fever
66
Where are latent virus become dormant
Nerve roots
67
What does Epstein-Barr virus do
- mild illness
- infects B cells
- epithelial cells of nose and mouth
- latent lifetime infection
68
How common is Epstein-Barr virus
90% of UK get it
69
What cancers does Epstein-Barr virus contribute to
- Nasopharyngeal carcinoma
| - Lymphoma
70
What are prions
- Proteinaceous Infectious particles
| - Lack nucleic acids (not living)
71
How do they cause damage
- abnormal—> accumulate in neural tissues
- abration
- very difficult to destroy
72
Name 3 prion diseases
- CJD
- Variant CJD
- Kuru
73
What is CJD
Creutzfeldt-Jakob disease
74
Describe CJD
- rare
- foetal
- degenerative neurological disease
75
How is CJD transmitted
- human growth hormone
- surgical instruments
- corneal grafts
76
Where does variant CJD occur
Young adults
77
Where is CJD thought to be driven from
BSE
78
How is kuru spread
Cannibalism, esp brains of relatives
