Phylogenetic analysis of bovine respiratory syncytial viruses from recent outbreaks in feedlot and dairy cattle herds.
Bovine respiratory syncytial virus (BRSV) is one of the major causes of bovine respiratory disease worldwide. In order to study the molecular epidemiology of the virus, samples from 30 BRSV outbreaks in cattle herds located in different parts of Sweden were collected from 2007 to 2011. The samples were analyzed by PCR, and the glycoprotein (G) gene was sequenced. BRSV was detected in outbreaks of respiratory disease in both dairy and feedlot herds most often during the winter period but also during the summer months (May to August). This indicates that circulation of the virus between herds occurs throughout the year. Comparative sequence analysis revealed a high degree (more than 94.5%) of sequence identity among the collected strains. Phylogenetic analysis showed that 29 out of the 30 strains formed a unique clade. Identical sequences found in herds sampled within a few months' time suggested that these herds were part of a common transmission chain. One strain from a single outbreak in a herd in southern Sweden clustered with Danish strains and showed a distant relationship to the rest of the Swedish strains. Further studies are highly warranted to clarify the inter-herd transmission routes of BRSV. Such knowledge is essential for the control of the spread of this virus between herds, regions and even countries.
Division of Ruminant Medicine and Veterinary Epidemiology, Department of Clinical Science, Swedish University of Agricultural Sciences, Box 7019, 750 07, Uppsala, Sweden.
Mehdi R M
MR
Bidokhti
Madeleine
M
Tråvén
Anna
A
Ohlson
Behdad
B
Zarnegar
Claudia
C
Baule
Sándor
S
Belák
Stefan
S
Alenius
Lihong
L
Liu
D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000821:virology*; D016000:Cluster Analysis; D004196:Disease Outbreaks; D014644:Genetic Variation; D005838:Genotype; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012367:RNA, Viral / Q000235:genetics; D018357:Respiratory Syncytial Virus Infections / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology; D018112:Respiratory Syncytial Virus, Bovine / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D017422:Sequence Analysis, DNA; D013548:Sweden / Q000453:epidemiology; D014759:Viral Envelope Proteins / Q000235:genetics
C066028:G protein, Bovine respiratory syncytial virus; D012367:RNA, Viral; D014759:Viral Envelope Proteins