Gut mycobiota alterations in patients with COVID-19 and H1N1 infections and their associations with clinical features

Abstract

The relationship between gut microbes and COVID-19 or H1N1 infections is not fully understood. Here, we compared the gut mycobiota of 67 COVID-19 patients, 35 H1N1-infected patients and 48 healthy controls (HCs) using internal transcribed spacer (ITS) 3-ITS4 sequencing and analysed their associations with clinical features and the bacterial microbiota. Compared to HCs, the fungal burden was higher. Fungal mycobiota dysbiosis in both COVID-19 and H1N1-infected patients was mainly characterized by the depletion of fungi such as Aspergillus and Penicillium, but several fungi, including Candida glabrata, were enriched in H1N1-infected patients. The gut mycobiota profiles in COVID-19 patients with mild and severe symptoms were similar. Hospitalization had no apparent additional effects. In COVID-19 patients, Mucoromycota was positively correlated with Fusicatenibacter, Aspergillus niger was positively correlated with diarrhoea, and Penicillium citrinum was negatively correlated with C-reactive protein (CRP). In H1N1-infected patients, Aspergillus penicilloides was positively correlated with Lachnospiraceae members, Aspergillus was positively correlated with CRP, and Mucoromycota was negatively correlated with procalcitonin. Therefore, gut mycobiota dysbiosis occurs in both COVID-19 patients and H1N1-infected patients and does not improve until the patients are discharged and no longer require medical attention.

Gut Microbiome Alterations in COVID-19

“…Unstable gut mycobiomes and prolonged dysbiosis persisted in a significant proportion (∼30%) of COVID-19 patients [14] . Another study investigated the gut mycobiota in both COVID-19 and H1N1-infected patients and found increased fungal load and enrichment of fungi, including Candida species, in both groups of patients [68] . Presence of A. niger was positively correlated with diarrhea, while abundance of Penicillium citrinum was inversely correlated with blood levels of CRP [68] .…”

“…Another study investigated the gut mycobiota in both COVID-19 and H1N1-infected patients and found increased fungal load and enrichment of fungi, including Candida species, in both groups of patients [68] . Presence of A. niger was positively correlated with diarrhea, while abundance of Penicillium citrinum was inversely correlated with blood levels of CRP [68] . Aspergillus infections were recently reported in respiratory tract secretions and tracheal aspirates in patients with COVID-19 [69] , [70] .…”

“…Secondary fungal infection or co-infection in patients with COVID-19 during the pandemic was frequently observed [73] , [74] , [75] . Candida and Aspergillus lineages were amongst the specific opportunistic fungal pathogens enriched in patients with COVID-19 during the disease course, particularly C. albicans [14] , [68] . C. albicans has been shown to impair gut microbiome assembly in both humans and mice, including gut microbiome re-assembly after disruption by antibiotics and inflammation [76] , [77] .…”

Gut and airway microbiota and their role in COVID-19 infection and pathogenesis: a scoping review

“…2 studies focused on intestinal dysbiosis post COVID-19 infection [ 28 , 33 ] and one study assessed the efficacy of faecal microbiota transplantation post COVID-19 infection [ 34 ]. Eight studies collected the microbiota DNA from stool samples [ 26 – 31 , 34 , 43 ] while 2 studies collected their samples from rectal swabs [ 32 , 35 ]. Five studies included participants who were administered antimicrobials and/or probiotics prior to sample collection [ 27 , 28 , 30 , 32 , 35 ], 3 studies excluded these participants [ 26 , 31 , 32 ] while 2 studies did not report this information [ 29 , 33 ].…”

The Salivary Microbiota of Patients With Primary Biliary Cholangitis Is Distinctive and Pathogenic

“…The reaction conditions comprised 30 s at 95°C, followed by 40 cycles of 5 s at 95°C and 34 s at 56°C, followed by 15 s at 95°C, 1 min at 60°C and 15 s at 95°C. qPCR calibration curves were constructed using linearized plasmid standards harbouring inserts of the PCR-amplified 16S rRNA gene of Escherichia coli ATCC 25922 as previously described ( 19 , 20 ). Sample DNA was analysed in duplicate.…”