The so called “sickness behaviour” induced by pro-inflammatory cytokines such as interleukin-1 (IL-1), interleukin-6 (IL-6) and tumour necrosis factor alpha (TNFα) includes symptoms such as malaise, fatigue, anorexia, cognitive problems and pain (Dantzer, 2009), which, if sustained, align with symptoms of mental disorders. Here, IL6 is linked to psychiatric disorder.