Myth or Fact?

I don’t need a booster because I got the vaccine.


Fact is – because the passage of time reduces the effectiveness of the initial vaccine series, getting the COVID-19 booster vaccine reduces your risk of being infected with the virus, becoming severely ill, or needing hospitalization.

Fact-Checked by: Dr. William Chasanov, Vice President and Chief Population Health Officer, Beebe Healthcare




Here is a list of facts, studies, and sources to reference on the booster’s effectiveness.

  • The initial effectiveness of two doses of Pfizer is 90%; getting a booster five months later takes it up to as much as 100% (CDC, 2022).
  • Moderna’s booster vaccine elevated antibodies against the omicron variant 37 times above the response from completing the primary series, and Pfizer’s booster increased the antibody response by 25 times over the primary series (NIH, 2022).
  • Those who are boosted are much less likely to test positive than those who had received just two doses (JAMA, 2022).
  • People who were unvaccinated for COVID-19 as the omicron variant emerged in December 2021 had nearly three times higher risk of infection than fully vaccinated adults, and five times higher risk than adults who had received a booster (CDC, 2022).
  • A third dose of Pfizer or Moderna reduces the chance of both an ED visit and hospitalization by 94%, compared with unvaccinated people, and reduces the chance of a trip to an urgent care clinic by 82% (CDC, 2022).



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As always, if you have questions about COVID-19 or the vaccines, you can always ask your health care provider.


Stats on COVID-19

For more data on Delaware COVID-19 cases including demographic breakdowns, go to My Healthy Community