Submitted to: Vaccine
Publication Type: Peer reviewed journal
Publication Acceptance Date: 12/2/2012
Publication Date: 12/14/2012
Citation: Fulton, R.W., Ridpath, J.F., Burge, L.J. 2012. Bovine coronaviruses from the respiratory tract: Antigenic and genetic diversity. Vaccine. 31(6):886-892. Interpretive Summary: Bovine respiratory disease (BRD) is a major health complaint for dairy and beef producers. BRD appears to be the result of interactions of a number of factors including stress, infection with bacterial pathogens and infection with viral pathogens. Researchers are trying to determine the nature of these factors in order to develop management practices that reduce BRD. The purpose of this research was to look at a particular group of viruses, called bovine corona viruses (BoCV), which have recently been isolated from cattle with BRD. BoCV were first discovered over 50 years ago in samples from calves suffering from diarrhea. In this study the BoCV from recent respiratory cases were compared with the BoCV from diarrhea cases (enteric disease). It was found that the respiratory viruses were different from the enteric viruses. This finding suggests that vaccines designed 20 to 30 years ago to combat enteric disease associated with BoCV infection my not work to control respiratory disease associated with more recent BoCV.
Technical Abstract: Bovine corona viruses (BoCV) isolated from respiratory tract, nasal swab and broncho alveolar washing fluid samples were evaluated for genetic and antigenic differences. These BoCV from the respiratory tract of healthy and clinically ill cattle with BRD signs were compared to reference and vaccine strains based on Spike protein coding sequences and VNT using convalescent antisera. Based on this study, the BoCV isolates belong to one of two genomic clades (Clade 1 and 2), which can be differentiated antigenically. The respiratory isolates from Oklahoma in this study were further divided by genetic differences into three subclades, 2a, 2b, and 2c. Reference enteric BoCV strains and a vaccine strain were in Clade 1. Currently available vaccines designed to control enteric disease are based on viruses from one clade while viruses isolated from respiratory tracts, in this study, belong to the other clade.