Oral Fungal Alterations in Patients with COVID-19 and Recovered PatientsOriginal paper
Karen Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease, four years before the first published case study.
Read MoreWhat was studied?
This study characterized the oral fungal microbiota, or mycobiome, in patients with COVID-19 and in recovered patients. Researchers used internal transcribed spacer (ITS) sequencing on tongue coating specimens to profile fungal communities. They compared fungal richness, diversity, and composition across COVID-19 patients, suspected cases, recovered patients, and controls, and examined correlations between distinct fungi and bacteria.
Who was studied?
The cohort included 71 COVID-19 patients, 36 suspected cases (SCs), 22 recovered COVID-19 patients, 36 SCs who recovered, and 132 controls, all from Henan. Tongue coating specimens were collected from each group for fungal sequencing. The study also used training, testing, and independent cohorts to validate a diagnostic classifier built from the sequencing data.
What were the most important findings?
Oral fungal richness was increased in COVID-19 patients compared to controls, and beta diversity analysis showed distinct fungal community structures between the two groups. The ratio of Ascomycota to Basidiomycota was higher in COVID-19 patients, and opportunistic genera including Candida, Saccharomyces, and Simplicillium were increased. A classifier built from two fungal biomarkers distinguished COVID-19 patients from controls across training, testing, and independent cohorts, and correctly identified SCs with positive SARS-CoV-2 IgG antibodies as COVID-19 patients.
What are the greatest implications of this study?
The findings suggest the oral mycobiome, including enrichment of opportunistic fungi such as Candida, may play a role in COVID-19 pathophysiology. Fungal biomarkers from tongue coating samples show potential as a noninvasive diagnostic tool for identifying COVID-19 cases, including those missed by other testing approaches. The documented correlations between oral fungi and bacteria point to cross-kingdom microbial interactions that merit further investigation in respiratory viral infection.