What Is the Role of Symptoms in Vaccine Development?

Symptoms are also crucial in the development and evaluation of vaccines:

1. Clinical Trials: During vaccine trials, researchers monitor participants for symptoms to assess the vaccine's efficacy and safety. The absence or reduction of symptoms in vaccinated individuals compared to a control group indicates vaccine efficacy.
2. Post-Marketing Surveillance: After a vaccine is approved, ongoing surveillance of symptoms helps detect any potential adverse reactions or breakthrough infections, ensuring the vaccine's continued safety and effectiveness.