MMP7 and infection: Similarly, previously infected individuals, in particular those with earlier infections before receiving the second dose exhibited a significant sustained upregulation of PARP-1 (FC = 2.10, p=1.19x10<sup>-5</sup>, pFDR=0.003) and downregulation of MMP-7 (FC = 0.58, p=2.19x10<sup>-5</sup>, pFDR=0.003) at 6-months post-booster.