Tumor necrosis factor (TNF) plays a pivotal role in meningococcal disease. The TNF response to endotoxin, however, differs between individuals and can be determined in whole blood samples ex vivo. The release of TNF in whole blood samples from 50 survivors of meningococcal disease 6-58 months after hospital discharge was studied. The TNF response was higher in patients who had experienced a moderately severe disease course compared with patients with a mild course. The TNF response was low again in the survivors of fulminant disease, who on original hospital admission presented with risk factors exposing them to a high chance of mortality (50% overall). On admission, the patients who did not survive had initial TNF levels three times higher than those in survivors with a clinical disease presentation of similar severity. Overall interpretation of these findings is that the innate TNF response may contribute to the outcome of meningococcal disease.