Seasonal difference in baseline cytokine levels.

<p>* <i>p < 0</i>.<i>05</i>, <i>**p < 0</i>.<i>01</i>, <i>*** p < 0</i>.<i>001</i> Kruskal-Wallis one-way ANOVA. Results are relative expression of cytokine levels compared to reference genes calculated using the ΔCq method [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0163780#pone.0163780.ref043" target="_blank">43</a>]. Box represents the 25^th to 75^th percentiles, middle line is median and whiskers are the minimum to maximum values.