Altered gut microbiota composition in children and their caregivers infected with the SARS-CoV-2 Omicron variant

Association Between Altered Microbiota Composition and Immune System-Related Genes in COVID-19 Infection

Microbiota and immunity affect the host's susceptibility to SARS-CoV-2 infection and the severity of COVID-19. This study aimed to identify significant alterations in the microbiota composition, immune signaling pathways, their potential association, and candidate microRNA in COVID-19 patients using an in silico study model. Enrichment online databases and Python programming were utilized to analyze GSE164805, GSE180594, and GSE182279, as well as NGS data of microbiota composition (PRJNA650244 and PRJNA660302) associated with COVID-19, employing amplicon-based/marker gene sequencing methods. C1, TNF, C2, IL1, and CFH genes were found to have a significant impact on immune signaling pathways. Additionally, we observed a notable decrease in Bacteroides spp. and Faecalibacterium sp., while Escherichia coli, Streptococcus spp., and Akkermansia muciniphila showed increased abundance in COVID-19. Notably, A. muciniphila demonstrated an association with immunity through C1 and TNF, while Faecalibacterium sp. was linked to C2 and IL1. The correlation between E. coli and CFH, as well as IL1 and Streptococcus spp. with C2, was identified. hsa-let-7b-5p was identified as a potential candidate that may be involved in the interaction between the microbiota composition, immune response, and COVID-19. In conclusion, integrative in silico analysis shows that these microbiota members are potentially crucial in the immune responses against COVID-19.

Application of myxovirus resistance protein A in the etiological diagnosis of infections in adults

BACKGROUND

Inappropriate antibiotic treatment for patients with viral infections has led to a surge in antimicrobial resistance, increasing mortality and healthcare costs. Viral and bacterial infections are often difficult to distinguish. Myxovirus resistance protein A (MxA), an essential antiviral factor induced by interferon after viral infection, holds promise for distinguishing between viral and bacterial infections. This study aimed to determine the ability of MxA to distinguish viral from bacterial infections.

METHODS

We quantified MxA in 121 infected patients via dry immunofluorescence chromatography. The Kruskal-Wallis test and receiver operating characteristic (ROC) curve analysis were used to determine the diagnostic value of MxA, either alone or in combination with C-reactive protein (CRP) or procalcitonin (PCT), in patients with viral, bacterial, or co-infections.

RESULTS

The value of MxA (ng/mL) was significantly higher in patients with viral infections than in those with bacterial and co-infections (82.3 [24.5-182.9] vs. 16.4 [10.8-26.5], P<0.0001) (82.3 [24.5-182.9] vs. 28.5 [10.2-106.8], P=0.0237). The area under the curve (AUC) of the ROC curve for distinguishing between viral and bacterial infections was 0.799 (95% confidence interval [95% CI] 0.696-0.903), with a sensitivity of 68.9% (95% CI 54.3%-80.5%) and specificity of 90.0% (95% CI 74.4%-96.5%) at the threshold of 50.3 ng/mL. Combining the MxA level with the CRP or PCT level improved its ability. MxA expression was low in cytomegalovirus (15.8 [9.6-47.6] ng/mL) and Epstein-Barr virus (12.9 [8.5-21.0] ng/mL) infections.

CONCLUSION

Our study showed the diagnostic efficacy of MxA in distinguishing between viral and bacterial infections, with further enhancement when it was combined with CRP or PCT. Moreover, Epstein-Barr virus and human cytomegalovirus infections did not elicit elevated MxA expression.

Profiles of gut microbiota associated with clinical outcomes in patients with different stages of SARS-CoV-2 infection

The correlation between SARS-CoV-2 infection and gut microbiota has been a subject of growing interest in recent research endeavors. It is postulated that SARS-CoV-2 might lead to gut dysbiosis by affecting the gut-lung axis and reducing the production of antimicrobial peptides in the gastrointestinal tract. Our comprehensive review of both in vivo and clinical studies has revealed a consistent decline in alpha diversity and increased dissimilarity in beta diversity of gut microbiota in comparison to healthy populations, observed during both the acute and post-infection phases of COVID-19. Furthermore, there is a notable reduction in the number of beneficial butyrate-producing bacteria, alongside an upsurge in opportunistic bacteria. Concomitantly, the functional and metabolic characteristics of gut microbiota are significantly altered. Consequently, COVID-19 patients exhibit a heightened inflammatory state, which has been linked to the severity of the disease in the acute phase and the occurrence of post-acute COVID-19 syndrome (PACS) in the post-infection phase. Notably, certain specific gut microbiota species have emerged as potential candidates for aiding in the diagnosis, prediction of disease severity, or treatment of severe cases of COVID-19. This review also underscores the significance of gut microbiota in the context of post-acute COVID-19 syndrome (PACS) and offers valuable insights into possible biomarkers for diagnosis and therapeutic targets for PACS in the future.

The Role of Bifidobacterium in COVID-19: A Systematic Review

The COVID-19 pandemic, caused by the SARS-CoV-2 virus, mainly causes respiratory and intestinal symptoms and changes in the microbiota of patients. We performed a systematic search in major databases using "Bifidobacterium" and "COVID-19" or "SARS-CoV-2" as key terms to assess the relationship of the genus to COVID-19. After the selection steps, 25 articles were analyzed. Of these, eighteen were observational, and seven were interventional articles that evaluated the use of Bifidobacterium alone or in mix as probiotics for additional treatment of patients with COVID-19. All stages and severities were contemplated, including post-COVID-19 patients. Overall, Bifidobacterium was associated with both protective effects and reduced abundance in relation to the disease. The genus has been found to be abundant in some cases and linked to disease severity. The studies evaluating the use of Bifidobacterium as probiotics have demonstrated the potential of this genus in reducing symptoms, improving pulmonary function, reducing inflammatory markers, alleviating gastrointestinal symptoms, and even contributing to better control of mortality. In summary, Bifidobacterium may offer protection against COVID-19 through its ability to modulate the immune response, reduce inflammation, compete with pathogenic microbes, and maintain gut barrier function. The findings provide valuable insights into the relationship between the disease and the genus Bifidobacterium, highlighting the potential of microbiota modulation in the treatment of COVID-19.