Viral infections alter the human salivary volatilome

The volatile metabolome, or volatilome, contains a wealth of information regarding individual health. Two parallel approaches can detect patterns of these volatile metabolites: chemometric analyses employing gas chromatography-mass spectrometry (GC-MS) or "noses" (trained animals or so-called electronic noses). While "noses" are exquisite odor discrimination tools, chemometric analyses are superior for determining the chemical identity of odorants related to disease conditions. Without identifying compounds altered by disease, it is difficult to uncover the responsible mechanism(s) and develop effective diagnostic tools. To understand how viral pathogens may alter the human volatilome, we collected saliva from healthy patients and patients with confirmed viral infections. Using headspace GC-MS analyses, we examined associations between 85 salivary volatiles and specific viral pathogens. Twenty-eight salivary volatiles were up- or downregulated (in relation to the healthy condition) by infection with one or more viral pathogens. Further examination indicated that salivary volatiles encode some level of viral specificity. In particular, SARS-CoV-2 infection produced a unique volatile pattern differing from several other common viral respiratory infections.IMPORTANCEThis research examined alterations of the salivary volatilome caused by confirmed respiratory virus infections. Results indicate that the salivary volatilome may specify the offending pathogen for improved clinical outcomes.