Vaccines

Question 1

List the ways of defence

Answer 1

• General
• Specific
• Eradication

Question 2

General defence

Answer 2

Surveillance + control

• Monitoring of virus activity
• Morbidity + mortality data
• Case + outbreak investigations
• Quarantines, restrictions, stamping out

Animal hygiene

• Feeding + keeping conditions

Question 3

Specific defence

Answer 3

In the host organism

• Antiviral drugs
• Interferons
• Immune sera
• Vaccines

In the environment

• Disinfectants

Question 4

Give the fields of resistance of viruses to environmental conditions

Answer 4

• Dehydration
  
  • Enveloped virus
• High temperature
  
  • Protein denaturation
• Radiation
  
  • Damage to NA
• Ionic environment

Question 5

Give examples of disinfectants

Answer 5

• Acids + bases
• Oxidants
• Halogenids

Question 6

Give examples of inactivating agents

Answer 6

• Formaldehyde
• NA denaturants

Question 7

Give the effects of antiviral medicaments

Answer 7

• Inhibition of virus replication
• The decrease of virus shedding
• The localisation of the infections
  
  • Infection remains however

Question 8

Give the problems of antiviral medicaments

Answer 8

• High viral mutation ratio - Resistance
• Close contact between virus + cell activity
  
  • Effective drugs not often toxic for the cells
    
    • Specific agents needed

Question 9

Nucleoside Analogues are divided into…

Answer 9

• First generation nucleoside analogues
• Second generation nucleoside analogues

Question 10

First generation nucleoside analogues

Answer 10

• Incorporated into the NA
• Toxic
• Topical ointments against herpes
• Ribavirin
• E.g IDU, TFT

Question 11

Second generation nucleoside analogues

Answer 11

• Activated by virus-specific enzymes
• More selective to viral polymerase than cellular
• Acyclovir
  
  • Selective to viral polymerase
  • Chain termination
• Zidovudine
  
  • Reverse transcriptase inhibitor
  • Chain termination
  • retroviruses

Question 12

Non-nucleoside Reverse Transcriptase inhibitors

Answer 12

• Indirectly inactivates RT
• Active against HIV-1
• Used in combination therapies

Question 13

Protease inhibitors

Answer 13

• Inhibits retroviral protease
• Fits into the active centre of the enzyme
• The cleavage of the precursor polyprotein is inhibited
• Effective against HIV

Question 14

Favipiravir

Answer 14

RdRp inhibitor

• Lethal mutations
• Broad spectrum

Question 15

Neuraminidase inhibitors

Answer 15

Used against influenza:

• Oseltamivir
• Zanamivir

Question 16

Methisazone

Answer 16

• Viral polymerase inhibitor
• Against pox-infections

Question 17

Amantadine, rimantadine

Answer 17

• Used against influenza
  
  • Ion channel inhibitor
  • Uncoating is defected

Question 18

Interferons, interferon inducers

Answer 18

• High efficiency
• Non-antigen specific
• Short effect
• Parenteral administration

Question 19

Immune sera + purified immunoglobulins

Answer 19

• Passive immunisation
• Short-term protection
• A danger of serum-sickness/anaphylaxis
• High cost
• Mainly in pet practice
  
  • Canine distemper + Parvovirus