BACK

Why does everyone have to get a vaccine for a vaccine to work?

Update

While the current data is promising, the study is ongoing, and more information is needed before Pfizer can pursue U.S. FDA approval. To ensure that there are not major safety concerns, the U.S. FDA is requiring manufacturers to provide at least two months of follow-up data for at least half of the volunteer participants. Most serious side effects from vaccines occur within about six weeks after the vaccine is given. In vaccine clinical trials, any observed impacts of the vaccine on volunteer participants are eventually considered side effects with more serious side effects causing the trials to pause or stop completely. No safety concerns about these potential side effects have been reported so far.

This article was published on
November 1, 2020

This explainer is more than 90 days old. Some of the information might be out of date or no longer relevant. Browse our homepage for up to date content or request information about a specific topic from our team of scientists.

Publication

What our experts say

While the current data is promising, the study is ongoing, and more information is needed before Pfizer can pursue U.S. FDA approval. To ensure that there are not major safety concerns, the U.S. FDA is requiring manufacturers to provide at least two months of follow-up data for at least half of the volunteer participants. Most serious side effects from vaccines occur within about six weeks after the vaccine is given. In vaccine clinical trials, any observed impacts of the vaccine on volunteer participants are eventually considered side effects with more serious side effects causing the trials to pause or stop completely. No safety concerns about these potential side effects have been reported so far.

Context and background

Herd immunity varies based off the infectious disease, but in most cases requires 70%-90% of the population to be vaccinated. For example, declining vaccination rates of MMR (measles vaccine), helped contribute to the uptick in cases.

Resources

JHU Herd Immunity and COVID (2020).

Media briefing

Media Release

Expert Comments: 

No items found.

Q&A

No items found.