Detection of cold-adapted vaccine-strain influenza virus using two commercial assays. Academic Article uri icon


  • Because of the contagious nature of influenza virus it is necessary to identify infected individuals after the virus is introduced into a population. The aim of this study was to characterise influenza virus detection with commercially available assays after intranasal vaccinating horses with cold-adapted influenza virus. Seven horses were vaccinated and placed with 3 unvaccinated horses. Nasal secretion samples were evaluated using 2 antigen detection assays. All 10 horses were positive in the Flu OIA assay during the study period, but only one horse was positive on one sample using the Directigen Flu A assay. Horses were most likely to be positive during the first 3 days following vaccination, and several horses were intermittently positive for several days after this. Obtaining positive test results from nonvaccinated, incontact horses suggests they became infected with vaccine-strain virus that was shed by vaccinated horses. These results are important for the correct interpretation of influenza antigen detection tests in situations when this modified-live intranasal vaccine has been used.

published proceedings

  • Equine Vet J

author list (cited authors)

  • Adam, E. N., Morley, P. S., Chmielewski, K. E., Carman, J., & Gonzales, G.

citation count

  • 10

complete list of authors

  • Adam, EN||Morley, PS||Chmielewski, KE||Carman, J||Gonzales, G

publication date

  • July 2002