The Meaning of Vaccine Is the Same as It Was in 1796, Regardless of Online Conspiracy Theories (2021)
historyofvaccines.org

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A reader sent in an email to our inbox at 2AM last night:

"It has come to my attention that the general definition of vaccine has changed, at least wrt Merriam Websters Dictionary. That publication has removed the use of the term "immunity." Is that where the medical definition is pulled from or is there a medical journal or dictionary that is used by the health care industry?

If not, I would think there needs to be a concerted effort, in these confusing times, to make very clear that the current usage of the word "vaccine" was different, prior to 2020-21.

Perhaps an alert or notation on your landing page warning that changes in the english language may make historical references difficult or unclear."

The origin of his question was unclear until a web search yielded an article from the Miami Herald and several mentions of this on social media. It appears that CDC did some editing on their website, and now " magically " the word "vaccine" has a completely different meaning. The Miami Herald explains it this way:

"Before the change, the definition for "vaccination" read, "the act of introducing a vaccine into the body to produce immunity to a specific disease." Now, the word "immunity" has been switched to "protection."

The term "vaccine" also got a makeover. The CDC's definition changed from "a product that stimulates a person's immune system to produce immunity to a specific disease" to the current "a preparation that is used to stimulate the body's immune response against diseases.""

And, yes, the Merriam-Webster definition of vaccine has changed from what it had in 2013 to what is there now, in 2021. But the change was from "immunity" to "immune response." Further reading of the definition of immunity defines it as what happens when an organism develops an immune response. It seems that the folks at Merriam-Webster did some editing,,,