biostudies-literatureUnknown15(1)Das BKThe rising incidence of invasive microbial infections and the expanding spectrum of pathogens make early and accurate identification of the causative pathogen a daunting task. Accurate diagnosis enables the identification and characterization of microbes and offers new possibilities for the control and prevention of infectious diseases. For the first time, we isolated and characterized three fungal species, viz., Mucor circinelloides, Fusarium equiseti, and F. incarnatum from hilsa (Tenualosa ilisha). The characterization was based on fungus morphology (in vitro culture and microscopy), molecular (PCR, sequencing and phylogenetic analysis) and virulence features (survival assay, histological examination). The naturally infected fish exhibited significant histomorphology alterations in the Scientific reports13957https://www.ebi.ac.uk/biostudies/studies/S-EPMC12015364biostudies-literatureMolecular characterization and virulence of fungal pathogens associated with mass mortalities in hilsa Shad (Tenualosa ilisha).PMC12015364Malick RCKumar VRathod SKSahoo AKBisai KDas BKRoy SChakraborty RJana AKAdhikari ASamanta SMajumder AfalseMolecular characterization and virulence of fungal pathogens associated with mass mortalities in hilsa Shad (Tenualosa ilisha).The rising incidence of invasive microbial infections and the expanding spectrum of pathogens make early and accurate identification of the causative pathogen a daunting task. Accurate diagnosis enables the identification and characterization of microbes and offers new possibilities for the control and prevention of infectious diseases. For the first time, we isolated and characterized three fungal species, viz., Mucor circinelloides, Fusarium equiseti, and F. incarnatum from hilsa (Tenualosa ilisha). The characterization was based on fungus morphology (in vitro culture and microscopy), molecular (PCR, sequencing and phylogenetic analysis) and virulence features (survival assay, histological examination). The naturally infected fish exhibited significant histomorphology alterations in the 2025-01-01T00:00:00Z2025 Apr2026-06-02T04:13:07.765Z2025-07-03T03:04:42.933ZS-EPMC120153644026347510.1038/s41598-025-94607-9