Molecular Identification and Phylogenetic Characterization of Candida Species Isolated from Oral and Nasal Samples of COVID-19 Patients in Duhok, Iraq
DOI:
https://doi.org/10.70099/BJ/2025.02.04.10Keywords:
COVID-19, Candida, molecular identification, ITS sequencing, phylogenetic analysis, fungal co-infection, CHROMagar, candidiasis, COVID-19–associated candidiasis (CAC)Abstract
The COVID-19 pandemic has been associated with an increased risk of opportunistic fungal infections, particularly candidiasis, in hospitalized and immunocompromised patients. This study aimed to determine the prevalence and molecular identity of Candida species isolated from oral and nasal swabs of COVID-19 patients in Duhok, Iraq. A total of 45 isolates were recovered from 14 of 100 patients. Candida albicans was the predominant species (17 isolates, 37.7%), followed by C. krusei (13 isolates, 28.8%), C. glabrata (9 isolates, 20.0%), and C. tropicalis (6 isolates, 13.3%). Although CHROMagar provided rapid preliminary identification, several isolates were misclassified phenotypically and required confirmation through ITS sequencing. Molecular analysis demonstrated clear species-level discrimination and revealed genetic diversity among clinical isolates. These findings highlight the importance of integrating molecular diagnostics into routine clinical workflows to improve the accuracy of Candida identification in COVID-19 settings, enabling timely management and reducing the burden of fungal co-infections.
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