The Different Types of Covid-19 Vaccines, Explained

How different companies are approaching the development of a new Covid-19 vaccine

In the 1760s — as smallpox was killing nearly 400,000 Europeans each year — a strange rumor started to spread: Dairy workers never seemed to contract smallpox.

This rumor reached a surgeon’s apprentice named Edward Jenner, who recognized that dairy workers had already been exposed to a similar virus called cowpox. Jenner started to inoculate children with cowpox, and the world’s first vaccination was born.

The principle behind Jenner’s approach — using a weaker version of a virus to create immunity to the more deadly version — is still used in some vaccines. But today there are many other methods for vaccine production, and these are being used to create new Covid-19 vaccines in record time.

Vaccine type #1: Live attenuated

The word “attenuated” means “reduced in force” or “weakened.” So, live attenuated vaccines contain an active but weakened version of the virus (this is similar to the idea used in the first smallpox vaccines).