Cases of myositis following COVID-19 vaccination have been documented. The clinical spectrum includes mild inflammatory myopathy, dermatomyositis, immune-mediated necrotising myopathy, and overlap syndromes. The relationship remains under study.  Be aware that mainstream will say these are “rare” so as not to “undermine” public confidence, but the facts are that widespread adverse reactions are well known.

Findings from the Literature

  • A 2023 review collected 49 cases of inflammatory myositis after COVID-19 vaccination. Muscle involvement was most frequent (~80 %), followed by skin manifestations (~53 %) and interstitial lung disease (~35 %). Most patients received mRNA vaccines.

  • Case reports have described anti-MDA5 dermatomyositis, overlap syndromes, and myositis combined with myocarditis following mRNA vaccination.

  • Symptoms usually onset days to weeks post-vaccine. Workup often reveals elevated CK, MRI muscle oedema, EMG myopathy patterns, and in some cases, myositis-specific antibodies (e.g. anti-MDA5, anti-PM/Scl). Biopsy, when done, shows inflammation, necrosis, and MHC-I upregulation.

  • Treatment generally involves high-dose corticosteroids, often with IVIG or immunosuppressants (methotrexate, mycophenolate, rituximab). Many patients improve, though anti-MDA5 + ILD cases carry higher risk.

Consent, Payments & Research Limitations

  • Under UK law and GMC guidance, informed consent must be obtained before vaccination, meaning patients should receive disclosure of benefits, risks, and alternatives.

  • Many report that full informed consent was not provided, particularly regarding long-term risks, rare adverse events, or ingredient details.

  • In the UK, GP surgeries are paid £7.54 per COVID-19 vaccine dose (plus £10 for housebound patients) and £9.58 per influenza vaccine, along with reimbursement of vaccine cost.

  • Because these payments underpin vaccine delivery further independent research may be underprioritised or underfunded, given the conflict between findings that might lower uptake and maintaining vaccine programme revenue.

Historical / Regulatory Notes

  • COVID-19 vaccination was initially not recommended for younger age groups until safety data were established.

  • Clinical trials and post-marketing surveillance continued well after roll-out; for example, long-term safety data collection extended into January 2023 and beyond.

Key Takeaways

  • Myositis after COVID-19 vaccination is documented but rare.
  • Onset typically occurs within days to weeks of vaccination.
  • Management with immunosuppressants often yields improvement.
  • Informed consent is mandated but often reportedly remains incomplete in practice.
  • GP payment per vaccine (COVID: £7.54 + housebound supplement; flu: £9.58) introduces systemic incentives.
  • Funding priorities and institutional alignment may suppress or disincentivise independent adverse event research.
  • Further prospective, independent studies are needed to assess incidence, mechanisms, and long-term safety.

Key References & Research Links

  1. Syrmou V, et al. COVID-19 vaccine-associated myositis: comprehensive review and case report. Immunologic Research, 2023. — PMC article: pmc.ncbi.nlm.nih.gov/articles/PMC10018601/

  2. González D, et al. Anti-MDA5 dermatomyositis after COVID-19 vaccination: a case-based review. PMC article: pmc.ncbi.nlm.nih.gov/articles/PMC9166182/

  3. Bolla E, et al. New-onset anti-MDA5 dermatomyositis following COVID-19 vaccination. PMC article: pmc.ncbi.nlm.nih.gov/articles/PMC11082759/

  4. Ding Y, et al. Inflammatory myopathy following coronavirus disease vaccination. PMC article: europepmc.org/article/pmc/pmc9634642

  5. Klein CR, et al. Anti-MDA5 autoantibodies predict clinical dynamics of dermatomyositis after SARS-CoV-2 mRNA vaccination. Rheumatology International (open access) — link.springer.com/article/10.1007/s00296-024-05683-5

  6. Camargo-Coronel A, et al. Idiopathic inflammatory myopathies linked to vaccination against SARS-CoV-2: a systematic review. Reumatismo PDF: reumatismo.org/index.php/reuma/article/download/1548/970/7027

  7. Reumatismo editorial / commentary: Myositis after SARS-CoV-2 vaccination occurs more frequently than assumed. (Reumatismo, 2023) — reumatismo.org