To track dispersion of IAV‐specific CD8+ T cells following IAV infection, we assessed CD25 and CD43 expression on tetramer‐binding cells to identify where the most recently activated CD25+CD43+ T cells were located and when they progressed to an effector (CD25−CD43+) and memory (CD25−CD43−) phenotype (Figure 4a).25 The IAV‐specific CD8+ T cells were first detected in the MLN at Day 4 after infection and had a predominantly CD25+CD43+ phenotype. Here, CD8A is linked to infection.