Use of rapid human respiratory syncytial virus strip tests for detection of bovine respiratory syncytial virus in experimentally vaccinated calves.

Three different rapid strip tests: TRU RSV, BinaxNOW RSV and RSV Respi-strip were compared with RT-PCR and ELISA BRSV Ag for the ability to detect bovine respiratory syncytial virus (BRSV) in nasal swabs collected from calves experimentally vaccinated with live vaccine Rispoval RS-PI3. The reference strains of BRSV (375 and A51908) were detected by ELISA BRSV Ag whereas the strains of human respiratory syncytial virus (HRSV) and bovine parainfluenza virus type 3 (BPIV-3) were not. All rapid strip tests as well as RT-PCR reacted positively both to HRSV and BRSV reference strains and negatively to BPIV-3. The detection limit for RT-PCR was 39.1 TCID50 (strain 375 of BRSV), whereas for each of the rapid tests it was approximately 156 TCID50 and 312 TCID50 for antigen ELISA. Diagnostic sensitivity in detecting BRSV in nasal swabs for TRU RSV and RSV Respi-strip tests was 33% and 50% for BinaxNOW RSV. Diagnostic specificity of TRU RSV was 100%, whereas for both BinaxNOW and Respi-strip it was 87%. We concluded that TRU RSV could be used as a supportive rapid test for BRSV screening in nasal swabs taken directly on a farm. However, due to the small group of animals used in the experiment, the results should be regarded as preliminary and the study should be repeated on a larger number of animals.