Sweat-prints of COVID-19: unique metabolite signatures.

AIM: The study of human sweat and its metabolite profile can reveal important metabolic processes. Metabolites produced during respiratory infections, such as Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), create unique odor signatures. This study aims to identify a distinct signature of SARS-CoV-2 infection through the analysis of sweat metabolites. MATERIAL AND METHODS: Sweat samples were collected from the axillae of individuals during the Delta and Omicron pandemic waves. Samples represent symptomatic (ventilator; n = 49), asymptomatic (home quarantine; n = 46) patients, and healthy individuals (n = 50) from Pune district, Maharashtra. Sweat metabolites were extracted under acidic conditions and analyzed using gas chromatography-mass spectrometry (GC-MS) with the NIST library and a hit threshold of 80%. The identified compounds were assessed for their origins and metabolic roles. RESULTS: Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) revealed distinct clustering of the groups. We report six compounds-6-ethyl-2-methyl decane, tetradecane, styrene, 2-ethyl-1-hexanol, 2-methyl heptane, and 1-ethoxy pentane-specifically in infected individuals. CONCLUSION: Alkanes and their derivatives were significantly abundant in the symptomatic cohort and linked to inflammatory lung conditions as compared to healthy controls, thus affirming the presence of a distinct sweat metabolite profile in SARS-CoV-2 symptomatic individuals.