Objectives

1. To identify the aetiology of CA-ARTI in a subset of participants in the WP4 trial, and to perform laboratory validations of the pathogen and host-based CA-ARTI-Dx evaluated in WP4, using samples obtained in the trial.
2. To provide comprehensive data on the laboratory-based validations (detection of pathogen, host biomarker, and AMR) of the CA-ARTI-Dx being evaluated on a regular basis in order to ‘machine-learn’ the clinical algorithms developed in WP1.
3. To screen for host biomarkers in an initial subset of blood/serum samples collected in WP4, and then validate these on the subsequent blood/serum samples from WP4.
4. To understand and quantify the burden of AMR, in a subset of nasal, pharyngeal and gastrointestinal samples, with respect to the type, days and doses of antibiotics prescribed based on the following outcomes: i) development or amplification of the AMR burden in the “normal” respiratory and intestinal flora after completion of antibiotic therapy, and ii) selection of pathogens with a resistant phenotype post therapy. These data will allow estimation of the cost of AMR and will feed into WP5.
5. To develop and support a biobank of well-characterized samples (including blood/serum and other relevant samples to be defined) and bacterial strains isolated from CA-ARTI patients.