IL6 and infection: In the case of IL-6, at 2 h post infection all the serotypes studied induce a statistically significant greater expression of this molecule compared to the uninfected condition, serotype a (p < 0.0001), b (p = 0.0010) and c (p = 0.0002), being also statistically significant higher for serotypes a (p = 0.0064) and b (p < 0.0275) than for serotype c.