Antigen detection within lymphoid tissues at different days post inoculation following challenge with the CI/89 strain of PPRV.

Tissues were taken on days 2, 5, 7, 9 and 21 and antigen detection was assessed by immunohistochemistry (IHC). Results for days 2 and 21 are omitted as all tissues analysed were negative for virus antigen. Average immunolabelling grades are given following analysis of tissues from 3 animals euthanased at each timepoint. Grades are formulated on a result of viral antigen density throughout a uniform tissue type. Sections were graded on three separate occasions, without referring to previous recorded results to help standardise the classification. Immunolabelling grades are defined as: 0 =  No immunolabelling seen; + =  Mild immunolabelling; ++ =  Moderate immunolabelling; +++ =  Marked immunolabelling. Intermediate grades exist between the above four categories to give the analysis a greater degree of flexibility. /− Tissue type not present within section.