Assays for antimicrobial activity and applications thereof

A method of adapting an antimicrobial treatment regime in a subject, the method comprising:

• (i) providing a first biological sample from a subject, wherein the subject is administered a broad spectrum antimicrobial treatment;
• (ii) assaying the first biological sample with a Fc domain-mannose-binding lectin (FcMBL) based microbe capture and detection assay for at least one component derived from, originated from, or secreted from a microbe;
• (iii) administering a first narrow spectrum antimicrobial treatment to the subject if assaying in step (ii) shows an increase in level of the at least one component in the biological sample relative to a baseline level;
• (iv) assaying a second biological sample with a FcMBL-based microbe capture and detection assay, wherein the second biological assay is obtained from the subject after administering of the first narrow spectrum antimicrobial treatment;
• (v) administering a second narrow spectrum antimicrobial treatment to the subject if assaying in step (iv) shows little or no change in level of the at least one component in the second biological sample relative to the baseline level;
• (vi) assaying a third biological sample with a FcMBL-based microbe capture and detection assay, wherein the third biological assay is obtained from the subject after administering of the second narrow spectrum antimicrobial treatment;
• and
• (vii) repeating steps (v) and (vi) with a different second narrow spectrum antimicrobial treatment until the assay of step (vi) shows an increase in level of the at least one component in the third biological sample relative to a baseline level.