Evaluation of species distribution and virulence factors of oralmycobiome in hospitalized patients with COVID-۱۹: A case–controlstudy

Background and Aim : COVID-۱۹ has highlighted the importance of paying attention to themycobiome of the oral cavity and its alterations. The oral mycobiome might favor a severeoutcome of COVID-۱۹ infection through different mechanisms, including alteration of therespiratory epithelium, promotion of adhesion of respiratory pathogens, increase of localinflammation, and related virulence factors. The present study aimed to determine the prevalenceand species distribution of oral mycobiome in patients with COVID_۱۹ and the virulence factorsof isolated fungal agents compared with healthy controls.Methods : We conducted a case–control study of ۱۴۴ patients with coronavirus infection and ۱۴۴controls. Cases and controls were matched for age, gender, body mass index, and the history ofreceiving antibiotic and antifungal medications. The study was carried out for ۱۲ months (May۲۰۲۱–May ۲۰۲۲) at Razi referral hospital, Rasht, Iran. All the samples were subjected to fungalculture and PCR-sequencing. The enzymatic activity index (EAI) was measured for importantvirulence factors including proteinase, esterase, and hemolysin activity using the relevantprotocols.Results : The results showed that in comparison with the control group, the prevalence of oralmycobiome in patients with COVID_۱۹ was ۳-fold higher. The genus of Candida (n=۱۵۲, ۱۰۰%)was the single fungal genus isolated from the oral mycobiome of COVID-۱۹ patients and healthycontrols and Candida albicans (n= ۱۳۸, ۹۰.۷۹%) was the most common isolated species.Phospholipase, proteinase, and hemolysin activity of Candida species was significantly higher inpatients than in healthy people. The activity of the Candida albicans virulence factors in bothgroups was greater than that of non-albicans.Conclusion : How the virulence factors of oral mycobiome are working in COVID-۱۹ patients isessential to develop new antifungal agents and determine the cause of drug resistance andmanagement of patients.

کلیدواژه ها:

Mycobiome ، COVID-۱۹ ، oral cavity ، Candida species ، Hemolysin factor ، Proteinase ، Esterase.