Got a Weird Taste in Your Mouth After the COVID Jab? A German Study Says You're Not Alone (But Don't Blame the Vaccine Just Yet)

Overview

Paper Summary › Explain Like I'm Five › Conflicts of Interest › Identified Limitations › Rating Explanation › Good to know › Topic Hierarchy › File Information ›

Paper Summary

Paperzilla title

This German study found that taste disturbances, oral herpes, and swollen tongue were the most common oral adverse events reported after COVID-19 vaccination, echoing similar findings in US data. However, the study relies on passive surveillance data and lacks comparator vaccines/drugs in the German dataset, making it hard to draw firm conclusions about causality or compare reporting rates across different vaccines.

Explain Like I'm Five

Scientists looked at reports from people in Germany after their COVID shots. They found some people said their taste changed, or they got cold sores, or their tongue felt big. But the scientists aren't sure if the shot caused it or if it just happened.

Possible Conflicts of Interest

The study was supported by the NPO 'Systemic Risk Institute', funded by the European Union. No other conflicts were disclosed.

Identified Limitations

Passive Surveillance Data

The study relies on passive surveillance data, which is subject to reporting biases, underreporting, and inconsistent data quality. This can affect the accuracy and reliability of the findings.

Lack of Comparator Data

The absence of comparator data in the German PEI dataset limits the ability to conduct a comprehensive disproportionality analysis. Cross-database comparisons with VAERS provide some context, but differences in reporting practices and data structure make direct comparisons challenging.

Reductive Classification Approach

The reductive classification approach of PEI (single term per report) may lead to underestimation of oral AE reporting rates. Oral AEs often co-occur with other symptoms, which may not be captured comprehensively.

Small Sample Size for Booster Series

Small sample size for the booster series group (0.65% of the dataset) may lead to increased variability and instability in the estimates, affecting the reliability of findings related to booster doses.

Lack of Causality

Causality cannot be established due to the observational nature of the study. The observed associations between vaccination and oral AEs do not necessarily imply a causal relationship.

Rating Explanation

This is an average study with several limitations inherent to its reliance on passive surveillance data and the lack of comparator data in the primary dataset. While the cross-database comparison and multivariable regression analyses provide some strengths, the inability to establish causality and potential underestimation of reporting rates limit the strength of the conclusions. Therefore, a rating of 3 is appropriate.

Good to know

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Topic Hierarchy

Domain: Health Sciences

Field: Medicine

Subfield: Pharmacology

File Information

Original Title: National Pharmacovigilance Assessment of Oral Adverse Events Following COVID-19 Vaccination in Germany (2020-2023)

Uploaded: July 22, 2025 at 07:29 AM

Privacy: Public