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Flashcards in Infection Session 1 Deck (48):
1

Why do antifungals have a high level of toxicity?

Fungi are eukaryotic cells (so are human cells) so it has hard to target fungus and not host cells

2

How are some individuals naturally immune to viruses?

Lack receptors for specific proteins/glycoproteins present on viral surface

3

What must the nucleic acid of a virus be supplemented by to form virions.

Host cell genes

4

Is the protein coat of all viruses similar?

No, varying degrees of complexity

5

What does the Baltimore classification system use to categorise viruses?

Nucleic acid structure and method of replication

6

Mycoplasma, Chlamydiae, Rickettsiae are all obligate intracellular parasites. What does this mean?

Need a cellular host to survive

7

Give an example of a ssDNA non-enveloped virus.

Parvovirus 19

8

Give an example of a dsDNA non-enveloped virus.

Adenovirus
HPV

9

Give an example of a dsDNA enveloped virus.

Herpes virus
Hepatitis B

10

Give an example of ssRNA +ve strand non-enveloped virus.

Coxsackie virus
Norovirus
Hep A&E

11

Give an example of ssRNA +ve strand enveloped virus.

HIV
Hep C

12

Give an example of a disease caused by a ssRNA -ve strand enveloped virus.

Ebola
Lassa Fever
Measles

13

Give and example of a dsRNA non-enveloped virus.

Rotavirus

14

What are bacteriophages?

Viruses that transmit DNA to a bacteria

15

How do bacteriophages cause disease?

Transmitted DNA codes for the production of toxins

16

How can bacteriophages contribute to antibiotic resistance?

Transmit DNA which contains resistance genes

17

Which part of the bacterial structure forms the basis for immunisations?

Polysaccharide capsule

18

What can bacteria release to aid pathogenesis?

Enzymes to increase invasiveness
Chemicals to gain nutrition from surrounding e.g. Iron

19

Which virulence factor do pili affect?

Adherence to host cells

20

How can obligate anaerobes survive in oxygen?

Form spores which coat the bacteria and protect it from oxygen

21

Why can't the same conditions used to kill vegetative bacteria be used for sterilisation?

Need much higher temperature and pressure to destroy spores

22

What system is used to name bacteria, fungi and parasites?

Linnaean

23

Give two examples of G+ve cocci.

Staph aureus
Coagulase -ve staphylococcus
Alpha- and beta-haemolytic streptococci
Strep pyogenes/pneumoniae
Enterococcus faecalis

24

Give two examples of G-ve cocci.

Neisseria meningitidis/gonorrhoea
Moraxella catarrhalis
Acinetobacter baumannii

25

Give two examples of G+ve bacilli.

Listeria monocytogenes
Bacillus anthracis/cereus

26

Give two examples of G-ve bacilli.

E. coli
Salmonella typhi
Klebsiella pneumoniae
Haemophilus influenzae

27

What is the causative agent in thrush?

Candida albicans

28

Which organism causes an AIDS defining meningitis?

Cryptococcus neoformans

29

What type of mould are ringworm and athlete's foot?

Dermatophytes

30

What are single-celled parasites called?

Protozoa

31

Give two examples of protozoa.

Giardia lamblia
Cryptosporidium parvum
Plasmodium falciparum

32

What category of pathogen do roundworms, tapeworms and flukes belong to?

Helminths

33

Give an example of a fluke which can cause malignancy.

Schistosoma mansoni

34

What S/S are associated with tapeworm infection?

None - usually asymptomatic but can cause neurological disease

35

What is the difference between yeasts and mould?

Yeasts are single celled fungi
Moulds are multicellular fungi

36

What is an infection?

Invasion of a host's tissues by microorganisms and disease

37

What are microbiota?

Microorganisms carried on skin and mucosal surfaces which are normally harmless or even beneficial

38

What are the three methods of horizontal transmission?

Contact
Inhalation
Ingestion

39

Why dint droplets spread as far as aerosols?

They are heavier

40

What are the stages that allow microorganisms to cause disease?

Exposure --> adherence --> invasion --> multiplication --> dissemination

41

Why is targeting the host immune response in treatment of infection potentially more effective than killing the pathogen itself?

Host immune response is usually more destructive

42

What are exotoxins?

Molecules released by a pathogen which can damage the surroundings to promote survival of the pathogen

43

What are endotoxins?

Parts of the bacterial cell wall which are released when the bacteria dies

44

What is the difference in supportive and specific investigations when identifying an infection?

Supportive identify to what extent a pt is unwell
Specific identify the causative agent

45

What supportive investigations can be performed in suspected infection?

FBC
CRP
LFTs
U&Es
Imaging
Histopathology

46

What is MC&S in specific investigations of infection?

Microscopy, Culture and antibiotic Susceptibility

47

Which specific investigations in infection can utilise dead pathogens e.g. in heart valve removal?

Antigen and nucleic acid detection

48

What virology specific investigations can be performed in a suspected infection?

Antigen detection
Antibody detection
Detection of viral nucleic acid