IL6 and malaria: The circulating levels of pro-inflammatory cytokines such as IL-6, IL-17, IL-12p40, and TNF were prominent in P. vivax naturally infected individuals when compared to plasma levels observed in other groups (malaria-naïve, endemic and P. vivax-treated) (Fig. 1a–d), although significant differences to control groups were observed only for IL-6 and IL-17 (p < 0.0001 and p = 0.0051, respectively) (Fig. 1a, b).