Bovine respiratory syncytial virus (BRSV) is pneumovirus closely related to human respiratory syncytial virus (RSV) that is a common cause of respiratory disease in

cattle Cattle (''Bos taurus'') are large, domesticated, cloven-hooved, herbivores. They are a prominent modern member of the subfamily Bovinae and the most widespread species of the genus ''Bos''. Adult females are referred to as cows and adult ma ...

, particularly calves. It is a

negative-sense In molecular biology and genetics, the sense of a nucleic acid molecule, particularly of a strand of DNA or RNA, refers to the nature of the roles of the strand and its complementarity (molecular biology), complement in specifying a sequence of am ...

single-stranded When referring to DNA transcription, the coding strand (or informational strand) is the DNA strand whose base sequence is identical to the base sequence of the RNA transcript produced (although with thymine replaced by uracil). It is this stra ...

RNA virus that replicates in the cytoplasm of the cell. Similarly to other single-stranded RNA viruses, the genome of BRSV has a high mutation rate, which results in great antigenetic variation. Thus, BRSV can be split into four different subgroups based on

antigen In immunology, an antigen (Ag) is a molecule or molecular structure or any foreign particulate matter or a pollen grain that can bind to a specific antibody or T-cell receptor. The presence of antigens in the body may trigger an immune respons ...

expression (A, B, AB, and intermediate).

Causes

In around 90% of cases, infection with BRSV results in secondary

bacterial pneumonia Bacterial pneumonia is a type of pneumonia caused by bacterial infection. Types Gram-positive '' Streptococcus pneumoniae'' () is the most common bacterial cause of pneumonia in all age groups except newborn infants. ''Streptococcus pneumonia ...

due to interference with the host's immune system and enhancement of bacterial adherence and colonisation by the virus. ''

Pasteurella multocida ''Pasteurella multocida'' is a Gram-negative, nonmotile, penicillin-sensitive coccobacillus of the family Pasteurellaceae. Strains of the species are currently classified into five serogroups (A, B, D, E, F) based on capsular composition and ...

'', a common commensal of the nasopharynx of cattle, appears to be the main bacterial agent in BRSV-related bovine respiratory disease (BRD).

Treatment

Similarly to other viral infections, treatment of BRSV is typically supportive. Anti-inflammatory drugs may be required to reduce fever and inflammation, which may increase the affected animal's food and water intake. Non-steroidal anti-inflammatory drugs (NSAIDs) are preferred to corticosteroids due to the latter's immunosuppressive effects. In the case of a secondary bacterial infection,

antimicrobials An antimicrobial is an agent that kills microorganisms or stops their growth. Antimicrobial medicines can be grouped according to the microorganisms they act primarily against. For example, antibiotics are used against bacteria, and antifungals a ...

may be given. In contrast to human RSV, commercial BRSV

vaccines A vaccine is a biological preparation that provides active acquired immunity to a particular infectious or malignant disease. The safety and effectiveness of vaccines has been widely studied and verified.< ...

are available. However, appropriate biosecurity measures and animal husbandry may be sufficient to prevent spread of disease.

References

{{Taxonbar, from=Q18965266 Bovine diseases Animal viral diseases Pneumoviridae