In the present study we therefore determined the prevalence and durability of cellular IFNγ responses to C. burnetii using a C. burnetii IGRA in comparison to serological detection in two cohorts of individuals, one from an area of past wide-spread exposure (>1500 individuals) and one from an area of lower prevalence (n=109) in the Netherlands, up to seven years after initial exposure and four years after the Dutch Q fever outbreak was resolved. This evidence concerns the gene IFNG and Q fever.