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Covid-19: Norway investigates 23 deaths in frail elderly patients after vaccination

BMJ 2021; 372 doi: (Published 15 January 2021) Cite this as: BMJ 2021;372:n149

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Gut Microbiome and Covid-19 mRNA Vaccine

Dear Editor

mRNA vaccine against Covid-19 has been designed to trigger an immune response to one of the surface spike proteins of the virus that enables its entry into human cells. The vaccine induces local inflammatory reactions. Recently, in Norway, 23 fragile vaccinated elders died due to common adverse reactions such as, fever, nausea and diarrhea.

Since human mucosal tissues of the gut are involved in immune response to Covid virus, adverse reactions could be due to dysbiosis of the gut commensals that change with age and personalized nutrition.

The gut microbe composition of individuals with a high intake of protein and animal fat, like the western diet, is generally dominated by a Bacteroides driven enterotype, which is the largest phylum of the gut microbiome community. Some genera of Bacteroidetes stimulate macrophages and monocytes to secrete a complex array of pro-inflammatory cytokines such as IFNγ and TNFα, neurotoxins including surface lipopolysaccharides and toxic proteolytic peptides in the plasma. Secretion of these cytokines and toxins result in aberrant immune responses, involving elevated levels of circulating cytokines and immune-cell hyperactivation, thus contributing to abnormal inflammatory reactions due to cytokine storms.

Therefore, during vaccination, rectifying gut microbiome dysbiosis with prebiotic and probiotic oral supplementation might be a solution for the management of Covid-19 vaccine induced adverse reactions.

Competing interests: No competing interests

23 January 2021
Mahejibin Khan
CSIR-Central Food technological Research Institute
CFTRI Mysuru,