How is vaccine effectiveness really measured? A new analysis suggests the numbers can be misleading because they don't fully account for the body's different types of immunity, such as in the blood versus the airways.

Questions are being raised about how we calculate the effectiveness of vaccines. Some experts believe the statistics we use might not be telling the whole story. They point out that proper data analysis requires a deep understanding of biology, not just numbers. For instance, an injected vaccine creates strong protection in our blood. However, it may not create the same level of defense in our nose and throat, which is the first place a respiratory virus attacks. This is called mucosal immunity. If the statistical models don't properly account for this important biological detail, the results for vaccine effectiveness can be difficult to understand or even appear inconsistent. This could lead to a flawed picture of how well the vaccines actually prevent infection and spread.

Original Author: Eyal Shahar | Source: Brownstone Institute