CD40LG and typhoid fever: There was also a positive correlation of MP-specific antibody responses between DBS eluates and plasma of typhoid fever patients at day 1 (IgA: r = 0.7, p = 0.01; IgG: r = 0.76, p = 0.001, and IgM: r = 0.8, p = 0.001; Fig 6D–6F).