Bovine respiratory syncytial virus (BRSV) is a respiratory virus that infects mainly cattle, but can also infect sheep and goats. It can vary in its ability to cause disease, ranging from fatal to no clinical signs shown. BRSV can also make the animal more vunerable to secondary infections, where the virus weakens the immune system so that bacteria that are usually harmless can cause disease. BRSV is a single stranded RNA virus that belongs to the Paramyxoviridae family of viruses, genus Pneumovirus. It is closely related to human RSV.

Associated diseases:

BRSV causes bovine respiratory disease and is also a component of the bovine respiratory disease complex.

Clinical Signs:

  • Watery to thick mucus from nose/eyes
  • Increased temperature
  • Increased breathing rate with open mouth
  • Decreased appetite
  • Appear depressed
  • Reduced milk production
  • Dry cough and difficulty breathing
  • Frothy saliva
  • Trouble drinking

Disease spread:

The disease is spread by infected animal aerosols, direct contact and transmission through objects (fomites). In outbreaks, infection rate is high but the fatality rate can be 0–20%.

Disease prevalence:

BRSV is globally spread and has an economic impact on beef and dairy producers.  

Impact for Society – what are we doing?

BRSV is the most important primary viral cause of respiratory disease in young calves in the UK, affecting approximately 1.9 million calves each year, at a cost of £54 million. Research at the Institute is ongoing to find components of the virus that could be suitable for vaccine use and to investigate ways to boost protective immunity against BRSV whilst avoiding potentially damaging immune responses.


* Image by Dr. H. Craig Lyerla courtesy of Public Health Image Library (PHIL)

Research papers

Guzman E, Taylor G (2015)

Molecular Immunology 66 (1) , 48-56
Blodorn K, Hagglund S, Gavier-Widen D, Eleouet J F, Riffault S, Pringle J, Taylor G, Valarcher J F (2015)

BMC Veterinary Research 11 , 76


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