Researchers found significant long-term effects, including a decrease in brain size, losses in grey matter in the olfactory areas linked to smell and regions linked to memory, and difficulties performing complex mental tasks when comparing the brain scans from individuals with a mild COVID-19 infection to scans from a control group. Read more about this study under Article 2.
Contents
- Article 1: Whole genome sequencing reveals host factors underlying critical COVID-19
- Article 2: SARS-CoV-2 is associated with changes in brain structure in UK Biobank
- Article 3: Immunopathological signatures in multisystem inflammatory syndrome in children and pediatric COVID-19
- Article 4: COVID-19 Vaccine Effectiveness against the Omicron (B.1.1.529) Variant
- References
Article 1: Whole genome sequencing reveals host factors underlying critical COVID-19
A recently published study in Nature identified 23 gene variants that are likely linked to severe COVID-19, including 16 variants that had not previously been reported. The identified genes are involved in antiviral defense (interferon signaling), immune cell differentiation, and a blood type feature called secretor status. Being a secretor means that your blood type is not only in your blood, but also in other body fluids like saliva. The study also provides evidence that coagulation (or blood clotting) plays a role in severe COVID-19. In summary, the data suggests that a failure to control viral replication and dysregulation of the inflammatory and coagulation responses are key mechanisms that lead to severe COVID-19.
Article 2: SARS-CoV-2 is associated with changes in brain structure in UK Biobank
Another study published in Nature found significant long-term effects, including: (i) an overall decrease in brain size, (ii) losses in grey matter in the olfactory areas linked to smell and regions linked to memory, and (iii) difficulties performing complex mental tasks when comparing the brain scans from individuals before and after a mild SARS-CoV-2 infection to scans from a control group. It is important to note that the scans were performed when the original virus and alpha variant were prevalent and loss of smell and taste a primary symptom. Whether these changes can be partially reversed, or whether these effects will persist in the long term, remains to be investigated.
Article 3: Immunopathological signatures in multisystem inflammatory syndrome in children and pediatric COVID-19
This study, also published in Nature, describes distinct immunological signatures in pediatric COVID-19 (pCOVID-19) versus multisystem inflammatory syndrome (MIS-C). While pCOVID-19 was characterized by robust type I interferon (IFN) responses, MIS-C was associated with IFNγ-dependent and NF-κB-dependent signatures, activation of extracellular matrix and increased levels of circulating SARS-CoV-2 spike protein. The study also confirms an earlier report linking MIS-C with the combination of the HLA-A*02, HLA-B*35 and HLA-C*04 alleles. Understanding the unique immunopathology of pCOVID-19 compared with MIS-C may guide better therapies for children infected with SARS-CoV-2.
Article 4: COVID-19 Vaccine Effectiveness against the Omicron (B.1.1.529) Variant
A study published in the NEJM indicates that two doses of vaccination with BNT162b2 or ChAdOx1 nCoV-19 are insufficient to give adequate levels of protection against infection with the omicron variant and mild disease. Boosting with BNT162b2 or mRNA-1273 provided a substantial increase in protection against mild disease, although waning occurred over time. Boosters will probably offer even greater levels of protection against severe and fatal disease. These findings support maximizing coverage with third doses of vaccine in highly vaccinated populations. Further follow-up will be needed to assess protection against severe disease and the duration of protection after booster vaccination.
References
[1] Kousathanas A et al. Whole-genome sequencing reveals host factors underlying critical COVID-19. Nature. 2022 Jul;607(7917):97-103. doi: 10.1038/s41586-022-04576-6. Epub 2022 Mar 7. PMID: 35255492; PMCID: PMC9259496. https://www.nature.com/articles/s41586-022-04576-6
[2] Douaud Get al. SARS-CoV-2 is associated with changes in brain structure in UK Biobank. Nature. 2022 Apr;604(7907):697-707. doi: 10.1038/s41586-022-04569-5. Epub 2022 Mar 7. PMID: 35255491; PMCID: PMC9046077. https://www.nature.com/articles/s41586-022-04569-5
[3] Sacco K et al. Immunopathological signatures in multisystem inflammatory syndrome in children and pediatric COVID-19. Nat Med. 2022 May;28(5):1050-1062. doi: 10.1038/s41591-022-01724-3. Epub 2022 Feb 17. PMID: 35177862; PMCID: PMC9119950. https://www.nature.com/articles/s41591-022-01724-3
[4] Andrews N et al. Covid-19 Vaccine Effectiveness against the Omicron (B.1.1.529) Variant. N Engl J Med. 2022 Apr 21;386(16):1532-1546. doi: 10.1056/NEJMoa2119451. Epub 2022 Mar 2. PMID: 35249272; PMCID: PMC8908811. https://www.nejm.org/doi/full/10.1056/NEJMoa2119451
