NEW STUDY: COVID-19 Vaccination Linked to 21 Oral Adverse Events

Pharmacovigilance analysis reveals oral tissue erosion, complete taste loss, burning mouth, tongue swelling, oral numbness, extreme tooth sensitivity, and canker sores following COVID-19 vaccination.

By Nicolas Hulscher, MPH

A major pharmacovigilance study published in the International Dental Journal analyzed nearly 1 million adverse event reports submitted to Germany’s Paul-Ehrlich-Institut (PEI) between December 2020 and December 2023. The focus: oral adverse events (AEs) following COVID-19 vaccination—an area largely overlooked in official safety assessments.

Researchers performed a retrospective review of 974,931 individual case safety reports (ICSRs) from the German PEI database. To validate their findings, they compared oral AE reporting trends to the U.S. VAERS database. They used both frequentist methods (Proportional Reporting Ratio [PRR], Reporting Odds Ratio [ROR]) and Bayesian signal detection (Information Component [IC]) to identify true safety signals—events reported disproportionately more often than expected compared to all other adverse events.

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21 Oral Health Issues Linked to COVID Vaccination

Researchers identified the following 21 statistically validated oral adverse events following COVID-19 vaccination. These reactions were reported far more often than expected, in both German and U.S. vaccine safety databases:

1. Loss of taste — 18× more likely than expected (PRR: 17.57); 2.2× higher risk after booster (aOR: 2.19)

2. Complete loss of taste (ageusia) — 16× more likely (PRR: 15.51); 3× higher risk after booster (aOR: 3.00); 3× higher in seniors (aOR: 2.99)

3. Distorted taste (dysgeusia) — 3× more likely (PRR: 3.31); 3.2× higher risk after booster (aOR: 3.20); 1.3× higher risk in women (aOR: 1.34)

4. Tingling or numbness in the mouth (oral paraesthesia) — 4.5× more likely (PRR: 4.47); 2.7× higher risk in women (aOR: 2.71); 3.2× higher after booster (aOR: 3.16); 1.5× higher with viral vector vaccines (aOR: 1.54)

5. Reduced sensitivity in the mouth (oral hypoaesthesia) — 4.3× more likely (PRR: 4.26); 2× higher risk in women (aOR: 2.04)

6. Swollen tongue — Nearly 3× more likely (PRR: 2.70); 2.9× higher risk in seniors (aOR: 2.87); 2.1× higher risk in women (aOR: 2.08)

7. Dry mouth — 2.6× more likely (PRR: 2.59)

8. Canker sores (aphthous ulcers) — 4.5× more likely (PRR: 4.48); 5.9× higher risk in children (aOR: 5.86); 3.9× higher after booster (aOR: 3.91)

9. Partial loss of taste (hypogeusia) — 3.6× more likely (PRR: 3.56); 1.8× higher risk in seniors (aOR: 1.80)

10. Burning mouth sensation (glossodynia) — 2.5× more likely (PRR: 2.49); 3.7× higher risk in women (aOR: 3.68); 3× higher risk in seniors (aOR: 3.00)

11. Numb mouth (oral anaesthesia) — 8× more likely (PRR: 8.31)

12. Painful or abnormal mouth sensation (oral dysaesthesia) — Extremely elevated signal (IC: 14.6)

13. Swelling around the mouth — 3.7× more likely (PRR: 3.68)

14. Redness of the tongue — 3.6× more likely (PRR: 3.60)

15. Numbness in teeth (dental paraesthesia) — 10× more likely (PRR: 9.97)

16. Extreme tooth sensitivity (hyperaesthesia of the teeth) — 9× more likely (PRR: 9.14)

17. Redness of the lips — 2.6× more likely (PRR: 2.59)

18. Lip irritation/disorder — Nearly 4× more likely (PRR: 3.92)

19. Itchy mouth (oral pruritus) — 2.4× more likely (PRR: 2.39)

20. Dry, cracked lips (chapped lips) — 2.5× more likely (PRR: 2.53)

21. Erosion or breakdown of oral tissue (oral mucosal erosion) — Strong signal (IC: 9.38)

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Mechanisms

The authors suggest several biological explanations:

• Neuroinflammation or demyelination of cranial nerves

• Spike protein interaction with oral sensory receptors

• Immune-mediated reactivation of latent herpes viruses

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COVID-19 vaccination is associated with a wide array of oral sensory and mucosal adverse events—many of which are frequent, underreported, and unacknowledged in current vaccine product labels or post-marketing surveillance protocols.

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Nicolas Hulscher, MPH

Epidemiologist and Foundation Administrator, McCullough Foundation

www.mcculloughfnd.org

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