TNF and Anorexia: There is now remarkably widespread acceptance that cytokines such as tumour necrosis factor (TNF) and interleukin-1 (IL-1) are the essential mechanism of systemic disease caused by infectious agents.53,54 High levels of these pro-inflammatory cytokines explain some of the notable symptoms of malaria disease such as anorexia, tiredness, aching joints and muscles, fever and sleepiness that patients experience in both Plasmodium vivax and Plasmodium falciparum malaria.55–57