Development and validation of a bovine parainfluenza virus type 3 indirect ELISA

Serological assays, including enzyme-linked immunosorbent assays (ELISA), provide an useful tool for screening animals for the presence of antibodies (Abs) against a wide range of infectious agents (including viruses that cause respiratory disease in cattle) and are mainly used in veterinary medicine to assist to the control and disease's monitoring. The aim of the present study was developing and validating one indirect enzyme-linked immunosorbent assay (ELISA) based on semi purified bovine parainfluenza virus type 3 (BPIV3).This test would allow to detect and quantify Abs against PI3 in serum sample from cattle and guinea pigs on both purposes diagnostic and typify/specify the quality of vaccines. The diagnostic sensitivity and specificity from the assay was 88% and 100% for bovine samples, using a threshold of corrected optical density, ODc =0.300, and 91% and 100% for guinea pig samples with a ODc =0.250.The intermediate precision expressed as the assays positive control coefficient of variation (CV) was 20% for bovines and 8.5% for guinea pigs. Both techniques reproducibility obtained in inter-laboratory assays was CV=17% for bovines and 15% for guinea pigs, which found the requirements of OIE (CV<30%). The efficacy of biological medicinal products, such as vaccines, relies an optimal model testing quality control. The validated ELISAs represents an important tool for testing vaccine quality, and quantifying and controling BPIV3 infections on cattle.