Epstein-Barr virus load in peripheral blood mononuclear cells in the cross-sectional study. Epstein-Barr virus (EBV) load distribution in control individuals (n = 15), spondylarthropathy (SpA) patients (n = 23), rheumatoid arthritis (RA) patients receiving methotrexate (MTX) (n = 18) and RA patients not receiving disease-modifying anti-rheumatic drug therapy (n = 26). Mean values of EBV viral load are represented by a black line. *Kruskall-Wallis test. PBMC, peripheral blood mononuclear cell.