4. Prevention and control of infectious diseases.

Question 1

Methods of prevention and control of diseases

Answer 1

1. Veterinary administration methods
2. Immune prophylaxis
3. Chemoprophylaxis

Question 2

1. Veterinary administration methods

Answer 2

Veterinary administrative rules
Notifiable diseases
International transport
General epidemiologic rules
Specific measures
International cooperation regarding infectious diseases

Question 3

2. Immune prophylaxis

Question 4

3. Chemophylaxis

Question 5

Notifiable diseases

Answer 5

Most severe diseases
Great economic impact, public health importance
National lists, EU lists, OIE lists

Question 6

International transport

Answer 6

Certified transportation, import bans can be implemented
o Certificates, traceability
o Import restrictions
o Quality requirements

Question 7

General epidemiological rules

Answer 7

All in, all out
Isolated keeping
Closed keeping
Isolation from wild
Arthropod control
Rendering dead animals, waste
Rules of hatching, transport of day-old chicken

Question 8

Specific measures for the specific diseases

Answer 8

Notifiable:
Closed herd, protection zone, observation zone, eradication/stamping out

Less important diseases:
Movement restriction, closed herd, diagnostic examination, treatment, vaccination

Question 9

Immune prophylaxis

Answer 9

Passive immunisation

• Hyper immune serum
• Maternal immunity

Active immunisation
- Vaccines

Question 10

Hyper immune serum

Answer 10

Artificial passive immunity
Homologous (from same sp): 2-3 weeks halflife
Heterologous: 7-10 days halflife

Question 11

Maternal immunity

Answer 11

Natural passive immunity (equivalent to yolk immunity) - contains maternal enteral lymphocytes and immunoglobulin
Eq, Su: epitheliochorial placenta - colostrum
Ru: syndsemochorial placenta - mainly colostrum
Car: endotheliochorial - diaplacental + colostrum

Give 10% of BW colostrum on first day

Quality depends on ag, nutrition of the dam
Certain ab can inhibit active immunisation

Question 12

Factors influencing efficacy of vaccines

Answer 12

Agent
Vaccine type
Amount of antigen
Method of vaccination
Age and health status of animal

Question 13

What types of vaccines exist?

Answer 13

Live vaccines
- Avirulent/attenuated strains
- Naturally or artificially attenuated strains
Inactivated vaccines
Adjuvants
Polyvalent vaccines

Question 14

Live vaccines pros and types

Answer 14

Faster immune response, less antigen needed, stronger response

1. Deletion vaccines (a part of gene related to virulence is deleted - IBR)
2. Vector vaccines (gene inserted into gene of pox virus that doesn’t cause disease - BVD)

Question 15

Not living vaccine types (9)

Answer 15

Inactivated deletion vaccines
Recombinant vaccines
VLP vaccines (only capsid-like structure)
Synthetic vaccine (protein chain is synthetic (FMD))
Nucleic acid vaccines (DNA, ss+RNA (mRNA vax like Pfizer, Moderna)
Transgenic plant vaccines
Non-replicating vector vaccines
Anti-idiotype vaccines

Question 16

DIVA principle

Answer 16

Differentiation between infected and vaccinated animals - both are seropositive
Discriminative ELISA
Inactivated FMD virus vaccines

Question 17

Eradication methods:

Answer 17

1. Selection (test and remove)
2. Generation shift
3. Herd replacement

(+ SPF method, Embryo transfer, antibiotics, eradication of smallpox, rinderpest)