Study Overview:
This real-world longitudinal study, conducted in Western Australia, evaluated the metabolic and immunologic responses of 33 individuals who received up to four doses of either Pfizer-BioNTech (Comirnaty™) or Oxford-AstraZeneca (Vaxzevria™) vaccines. We tracked 34 cytokines, 112 lipoprotein markers, and 21 low-molecular-weight metabolites over a period extending up to 480 days after the first dose. Samples were collected immediately before and within two weeks after each vaccination to capture both short- and long-term biological responses.
Key Findings: ![]()
1. Temporary Immune Activation
After vaccination, a short-lived increase was observed in inflammatory cytokines such as IP10 (CXCL10) and MIP-1β. Importantly, these cytokine levels quickly returned to baseline and remained well within normal healthy ranges between doses, indicating a controlled and transient immune response, distinct from the serious inflammatory patterns seen in COVID-19 infections.
2. Metabolic Stability
Metabolic profiling revealed minimal changes following vaccination.
To assess this, the vaccinated cohort's samples were compared to two reference groups:
- Individuals with mild COVID-19 infections (PCR-positive, non-hospitalized), and
- Healthy controls with samples collected before the pandemic.
Using mathematical modelling, we found that over 95% of the vaccinated individuals' blood profiles resembled healthy controls, not those with COVID-19 infection.
Approximately 5% of samples showed metabolic fingerprints more similar to mild COVID-19 cases. Notably, half of these samples came from one individual later diagnosed with long COVID after overseas travel.
3. Small and Isolated Metabolic Shifts
Further analysis found a temporary increase in glutamic acid levels after the third vaccine dose. While intriguing, given glutamic acid’s role in immune regulation and cardiovascular health, the glutamine-to-glutamic acid ratio remained within normal ranges, suggesting no adverse functional impact.
Why It Matters:
This study provides real-world evidence that repeated COVID-19 vaccination does not induce harmful metabolic effects. It offers important reassurance for individuals seeking to stay current with recommended vaccine schedules without fearing long-term metabolic consequences.
Full Study:
The research is published in the Journal of Molecular Medicine:
Longitudinal study on immunologic, lipoproteomic, and inflammatory responses indicates the safety of sequential COVID-19 vaccination
Media:
Dr. Norman Swan discusses the findings on the ABC Health Report.
Listen here