5. How are vaccines developed?
For a new vaccine, there are several steps to make sure it is safe and effective. Click each of the six stages of the vaccine development journey to discover how patient safety is protected and vaccine efficacy is tested.
Development Pathway Narration
A vaccine is developed and tested in the laboratory to ensure it protects against the disease being studied.
The new vaccine is tested on 20 -100 healthy volunteers to see how it works in people. Is it safe? Does it produce the expected immune response?
The vaccine is tested on several hundred people. What dose is needed, how many doses? What are the most common side effects?
The vaccine is tested on thousands of volunteers, often from different countries, different ages, different backgrounds. What are the rare side effects? Is it effective? Efficacy is measured by how many vaccinated people get the illness (and how severely) compared to those who have had a placebo (dummy) vaccine.
Medical and health authorities in Individual countries assess the published results of vaccine studies and give approval for its use in the general population.
Vaccine safety is monitored nationally and globally to identify any concerns or very rare side effects e.g., those affecting only a few people per million. This is to make sure that the benefits continue to outweigh any possible side effects. Also, action can be taken where individuals are at increased risk of rare side effects.