Proteins most strongly associated with a participant’s infection status included peptides with validated antimicrobial activity (IFIT3 (ref. 39), DEFB4A40), products of AD risk genes (APOE41, TREM2 (ref. 42)) and several proteins that we recently showed to be associated with inflammatory dietary patterns and adverse neurocognitive outcomes (CDCP1 and CCL3 (ref. 43)). Here, TREM2 is linked to infection.