evidence: The Pfizer and Moderna COVID-19 vaccines were the first mRNA vaccines that humans received outside of clinical trials. [...] Dr. Kenyon explained that mRNA vaccines deliver the coronavirus S protein’s genetic material. Our own cells then use the information stored in the mRNA to make the S proteins. The immune system is then "trained" to recognize these spikes, preparing it for a future attack. [...] Another concern is whether natural immunity would be more effective than a vaccine. However, a CDC study from November 2021 found that COVID-19 mRNA vaccines are about "Natural immunity is not better than vaccine-acquired immunity. These vaccines have the potential to provide you with protective immunity without the risks associated with infection," Dr. Yager told MNT.