Respiratory disease in adult farmed animals

Question 1

What is IBR?

Answer 1

Infectious Bovine Rhinotracheitis. 
•	Highly infectious and contagious
–	Bovine Herpes Virus 1
Classification:
–	Alphaherpesvirus
•	Several strains of BHV-1
•	Europe, North America and Africa
–	Gammaherpesvirus
•	Rhadinoviruses such as BHV-4 and OHV-2
Eradication campaigns underway in some countries:
–	Denmark, Finland, Sweden successfully free
•	marker vaccines, blood testing and movement restrictions.

Question 2

What is the epidemiology of IBR?

Answer 2

–Respiratory infection spread by aerosol
–Direct contact or shared air space for sustained period
–Variable incubation period of 10-20 days
–Latency
•Once infected (or vaccinated with a live vaccine), the animal remains infected for life
–Neuro-invasion (retrograde axonal transport up the trigeminal nerve?)
•Re-activation and shedding follows periods of stress.
–Calving, movement, illness, corticosteroid use
–Virus travels down axon to primary site of entry.