Bovine herpervirus type 1: infection and diagnosis methods

Abstract

Bovine herpervirus type 1 (BHV-1) is widespread in beef and dairy herds, causing great economic losses in cattle breeding. Infections caused by BHV-1 involving the respiratory, genital, reproductive and nervous systems can determine a wide variety of clinical manifestations wich are common on the other infectious and parasitic diseases. Several methodologies have been developed for laboratory diagnosis of BHV-1. Traditional serological techniques are unable to diferentiate animals exposed to the virus strains in the vaccine from those seropositives by natural exposure to the field strains. Thus the diagnosis can only be conclusive by detecting BHV-1 directly in clinical samples. Virus isolation has the disadvantage of requering viability in the viral particle, which in many situations may reduce the sensitivity and specificity of the technique. The immunoperoxidase and immunofluorescent techniques, although they do not require the infectiousness of the virus, can be seriously compromised if the structural integrity of the viral particle is not maintained. Currently the polymerase chain reaction assay is being universally adopted in the diagnosis of many virus, including BHV-1. This methodology has the advantage of not requiring the viral particle viability while providing high sensitivity and specificity and fast results.