Furthermore, over the whole post-infection period there was a negative correlation between pathology intensity and percentages of CD4+ and CD8+ within SMLN lymphocyte pool for both 1×104 IFU (pathology score vs. CD4+ Pcc = -0.598, P = 0.005; pathology score vs. CD8+ Pcc = -0.679, P = 0.001) and 1×106 IFU inoculated (pathology score vs. CD4+ Pcc = -0.462, P<0.05; pathology score vs. CD8+ Pcc = -0.637, P<0.005) guinea pigs. This evidence concerns the gene CD4 and infection.