Location: Animal Diseases Research
Title: Diagnostic assays used to control small ruminant lentiviruses Author
Submitted to: Journal of Veterinary Diagnostic Investigation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 18, 2010
Publication Date: November 20, 2010
Citation: Hoesing, L.M. 2010. Diagnostic assays used to control small ruminant lentiviruses. Journal of Veterinary Diagnostic Investigation. 22(6):843-845. Interpretive Summary: The small ruminant lentiviruses (SRLV) include caprine arthritis-encephalitis virus, maedi-visna virus, and ovine progressive pneumonia virus. This paper is a review article on the performance of various serological and molecular diagnostic assays used to evaluate the presence of SRLV infections. Many factors control the performance of the SRLV assays including the following: format of the assay, SRLV strain similarity between the SRLV strains used in the assay reagents and the SRLV strains in the flock or herd, and the amount of virus in a given host. In addition to the serological and molecular assays, future sheep and goat genomic assays may help to predict whether the animal will be able to control or resist SRLV infection.
Technical Abstract: The serological diagnostic tests such as the agar gel immunodiffusion (AGID) assay and various types of enzyme linked immunosorbent assays (ELISAs) have contributed to the reduction of small ruminant lentivirus infections worldwide. Since there are no treatments or efficacious vaccines, the serological diagnostic tests have supported most of the eradication efforts by testing and removal or separation of adult animals that generate antibodies to small ruminant lentiviruses (SRLVs). With the advent of the molecular age, standard and quantitative PCR-based assays for the detection of provirus in peripheral blood cells are becoming more common and aid in the detection of infected goats and sheep even prior to antibody detection by ELISA in some animals. Performance of the serological and molecular diagnostic tests is dependent upon a number of factors including the format of the assay, percent identity between the viral sequences in a flock or herd of a certain geographical region and the viral sequences used to generate SRLV test reagents, and the intrinsic pathogenesis or amount of provirus and SRLV antibody generated in a species or individual small ruminant. In addition, small ruminant genomics may help with establishing genetic markers of SRLV-infection and disease, which could greatly aid the small ruminant producers of the world.