Rapid classification of COVID-19 severity by ATR-FTIR Spectros-copy of plasma samples

In this study, we investigated the potential of Attenuated Total Reflectance Fourier-Transform Infrared (ATR-FTIR) spectroscopy on SARS-CoV-2 plasma samples. An algorithm such as partial least squares-discriminant analysis (PLS-DA) was used to build the model and tested using data from 130 and 30 patients, respectively. Key clinical parameters (age, sex, diabetes mellitus and hypertension) were also included which resulted in area under the ROC curve (C statistics) for both the training and test datasets 85.7% (78.6-92.8%), and 85.1% (71.3-98.8%), respectively. The test result showed 69.2% specificity (42.4-87.3%) and 94.1% sensitivity (73.0-99.0%). Diabetes mellitus was the strongest predictor in the model, followed by FTIR regions 1020-1090 cm-1 and 1588-1592 cm-1. In summary, this study demonstrates the potential of ATR-FTIR spectroscopy as a rapid, low-cost COVID-19 severity triage tool to facilitate COVID-19 patient management during an outbreak.