IL9 and infection: The Plasma IL-9, a growth factor and antiapoptotic cytokine that is primarily expressed by activated T cells, were significantly decreased at 1 dpi (mean ± SE; 0.010 ± 0.004, p = 0.004), 2 dpi (0.009 ± 0.005, p = 0.003), 3 dpi (0.011 ± 0.005 pg/mL, p = 0.003), 4 dpi (0.017 ± 0.006, p = 0.008), and 5 dpi (0.020 ± 0.006, p = 0.017) compared to the pre-infection time point (0.047 ± 0.009).