CD40LG and infection: For IgM ELISA, FL or FL/BCL mutant VLP can improve the specificity of WT VLP from 91.4−96.4% to 93.7−99.3% while maintaining a high sensitivity (91.7−100%) for primary infection panels (pZIKV, pDENV1 and pWNV) comparable to that of WT-VLP (94.4−100%) (Table 2).