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Flashcards in Control of Viral Population Deck (40)
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1

ways to control viral population

• Quarantine
• Good hygiene
• Changes in lifestyle
• Elimination of a vector
• Immunize the population
• Development and implementation of antivirals

2

ways to control outbreak

ID source/reservoir, clean-up, quarantine, immunization, etc.

3

Universal precautions when handling blood

assume contamination

4

Essential in hospital / health care settings in order to control viral disease

Limit contact, immunize health care workers, improve hygiene

5

disinfection for virus

70% ethanol, 15% chlorine bleach, autoclaving

6

is education (public, research) important for viral control

yeah

7

vaccines for virus

1) Inactivated (killed)
2) Live-attenuated
3)Subunit
4) DNA

8

difference between prophylactic and therapeutic

prophylactic - used to prevent contracting infection
therapeutic - used to treat once infection has been contracted

9

ways to prevent or treat viral populations

vaccines, antivirals, stimulate host innate immune system

10

ways to stimulate host innate immune system

– Interferon (induces synthesis of cellular proteins capable of inhibiting translation or transcription)
– Activate NK kills (agents that bind to toll-like receptors)
– Antibodies (natural or passive immunization)

11

what qualities make a vaccine good?

– Cheap (for majority of vaccines, new vaccines usually much more expensive)
– Used before discovery of viruses
– Result in decline of illness and death (polio, MMR, etc.) - humans and animals
– Eradication (smallpox)

12

what are live attenuated vaccines

LIVE virus particles that grow in the vaccine recipient but do not cause disease because the vaccine has been altered (mutated) to a non pathogenic form

13

examples of infections treated with live attenuated vaccines

Polio (Sabin), MMR, Yellow fever, Rotavirus, Varicella

14

what are inactivated vaccines

Preparations of the normal (wild type) infectious, pathogenic virus then rendered non-pathogenic usually by chemical treatment such as with formalin that cross- links viral proteins

15

example of infections treated with inactivated vaccines

Polio (Salk), Influenza, HepA

16

what are subunit viral vaccines

• Purified virus components
• Recombinant proteins that self-assemble
into Virus Like Particles (VLPs) and they help host form resistance

17

example of viruses treated with subunit

HepB, Quadrivalent HPV

18

what type of vaccine is gardasil

subunit

19

how does HPV vaccine work

-- Recombinant L1 proteins that self-assemble into VLPs and is given before the onset of sexual activity
– ~100% protection from infection with vaccine HPV types
– Potential to prevent ~70% of cervical cancers,
~90% of genital warts

20

what is a DNA viral vaccine

-Usually harmless viruses into which a gene for a (supposedly) protective antigen has been spliced
-Protective antigen is then made in the vaccine recipient to elicit an immune response

21

how do antivirals work

they interfere with virus specific functions and interfere with cellular functions (preferably virus infected)

22

properties of antivirals

water soluble, taken up by cells, stable

23

what are antivirals not?

– toxic
– carcinogenic
– allergenic
– mutagenic
– teratogenic

24

what properties make a good medicine

-activity
-solubility
-oral bioavailability
-half life
-metabolic profile/toxicity

25

viruses treatable with antivirals

• Herpes simplex virus
• Varicella-zostervirus
• Cytomegalovirus
• Human immunodeficiency virus
• Influenza A and B viruses
• Respiratory syncytial virus
• Hepatitis B and C viruses
• Papillomavirus
• Picornavirus

26

goal of antivirals

virion disruption or inhibition of life cycle

27

how do antivirals block attachment hence blocking subsequent stages

– tends to be virus specific, more for prophylaxis
– neutralizing antibodies bind viral receptors 􏰂 prevent attachment of the virus to the host cell

28

how do antivirals block penetration

fusion inhibitors

29

how do antivirals block uncoating

– amantadine

30

how do antivirals block replication

– Nucleoside analogues: incorporated into viral genomes
– Get chain termination: analogues lack hydroxyl groups for linking of backbone