1. CATTLE: Bovine Respiratory Syncytial Virus (BRSV) PARAMYXOVIRIDAE Flashcards
RS-VIRUS INFEKTIO
BOVINE RESPIRATORY DISEASE complex
-More commonly in young animals during period between passive and active immunity
-Terminology in use:
>Enzootic pneumonia
>“Shipping fever”
>Pneumonic pasteurellosis – Pasteurella spp and >Mannheimia spp
>Atypical interstitial pneumonia – Dictyocaulus viviparus
-Clinically BRD appears as pneumoenteritis
>Many pathogens affect resporatory tract and intestinal tract at the same time
BRD is defined as a “disease complex”:
-It usually is caused by a variety of pathogens, both viral (Bovine Respiratory Syncytial Virus (BRSV), ParaInfluenza 3 (PI3), Adenovirus, Bovine Viral Diarrhea Virus (BVDV), and Infectious Bovine Rhinotracheitis (IBR)) and bacterial (Pasteurella multocida, Mannheimia haemolytica, Histophilus somni, Mycoplasma bovis).
-Parasitic (lungworm) and fungal (Aspergillus) agents are also pathogens.
-These pathogens interact with one another and the animal’s immune system to produce full-blown disease.
-Bacterial pathogens apparently cause the acute syndrome by invading the bovine respiratory tract that has been compromised by viral infections, environmental conditions and/or other stress factors.
-Contributing to the disease complex is stress. Stressors include weaning, changes of feed, variation in ambient temperature and humidity, and weather.
disease
-BOVINE RESPIRATORY SYNCYTIAL VIRUS INFECTION (BRSV)
-Bovine respiratory syncytial virus
> Paramyxoviridae
Pneumovirus
-FIN: RS-virus infektio
infectious disease of cattle
caused by
Paramyxovirus
characterized by
fever, infection of upper respiratory tract and bronchopneumonia
agent
-Bovine Respiratory Syncytial Virus BRSV
-genus: Pneumovirus
-family: Paramyxoviridae
-RNA virus
-2 serotypes
-3 antigenic subtypes: A, AB and B
BRSV was named for its characteristic
cytopathic effect - formation of syncytial cells
A syncytium or symplasms (from Greek: sun. together and box i.e. cell) is multinucleate cell that can result from
multiple cell fusions of uninuclear
HR
-cattle
-human RSV is pathogenic to calves, but BRSV is NOT zoonotic!
more severe clinical disease can be seen in
-1-3 month-old
> maternal antibodies do not prevent clinical disease
> mortality in this age group is 5-20%
spread
-quickly within herd
> morbidity 80-100%
on primary induction to herd
severe pneumonia in all age groups
seasonality
-more common during fall and winter
> reinfections during summer months
has been isolated in
-most European countries
-North-America
-Australia
-Japan
-Africa
transmission: excretion
nasal discharge
transmission: mode of transmission
-aerogenic
(-fomites: including human)
transmission: route
respiratory
IP
3-5 days
CS-common signs
-fever (40-42)
-depression
-decreased feed intake
-increased respiratory rate
-cough
-nasal and lacrimal discharge
CS: subcutaneous emphysema
may occur
CS: secondary bacterial pneumonia is
frequent occurrence
recovery
in 1-2 weeks
what disease
BRSV
PM
-diffuse interstitial pneumonia with dub pleural and interstitial emphysema along with interstitial edema
-bronchopneumonia
DDx
-Parainfluenza-3 (PI-3)
-Bovine Herpesvirus 1 (BHV-1)
-Bovine Virus Diarrhea virus (BVDV)
-Adenoviruses
diagnosis: material
-nasal swabs
-lung, trachea, bronchial LNs
diagnosis: in the lab
-virus identification - PCR
-antibodies - serology (ELISA)
Tx
-no specific Tx
> mainly supportive care-IV fluids and electrolytes due dehydration
> in severe cases also NSAIDs can be used
> ABs if secondary infections
secondary bacterial infections are common
-M. hemolytica
-P. multocida
-H. somni
vaccine
-vaccines are available- efficacy
>also in Estonia
-BioBos Respi4: Bovine parainfluenza virus vaccine + Bovine respiratory syncytial virus vaccine (BRSV) + Bovine viral diarrhea vaccine (BVD) + Pasteurella vaccine
