Vaccine Science

For some people, COVID-19 can be a mild illness. However, it can cause serious complications or death for others — including healthy people. The vaccine is important in helping to prevent or reduce the effects of COVID-19.

Prevention is key to helping end the pandemic. Experts say that 75% to 85% of the population needs to get vaccinated to achieve herd immunity.

Myths and Misconceptions

UF Health expert Dr. Michael Lauzardo discusses myths and misconceptions about the vaccines and how best to inform yourself.

Dr. Michael Lauzardo Answers Questions About Vaccine Safety and Effectiveness Play Video

Is one of the COVID-19 vaccines better than the other?

The FDA applies the same review process to all vaccines, regardless of the manufacturer. The CDC Advisory Committee on Immunization Practices, or ACIP, is a group of medical and public health experts that develops recommendations on how to use vaccines to control diseases in the United States. The approved Emergency Use Authorization, or EUA, vaccine produced by Pfizer-BioNTech has been shown to be at least 90% effective.

How many doses of the vaccine will I need?

We are currently distributing the Pfizer-BioNTech vaccine, which requires two doses. The second dose will be given 17-21 days after the first one. Although some degree of immunity might be provided with the first dose, the studies to look at how the vaccine worked using two doses. When you schedule your first dose, you will also be prompted to schedule your second dose.

How soon after getting vaccinated am I protected?

After you are vaccinated, you should develop immunity in about one to two weeks, but the specific timeline for any COVID-19 vaccine will depend to some extent on which type of vaccine it is.

What does 95% vaccine efficacy mean?

If I have already had COVID-19, should I still get the vaccine? 

Yes, we recommend you get the vaccine even if you’ve already had COVID-19. Studies show that having COVID-19 might offer some natural protection from reinfection. But those studies also show the protection might not last very long. The vaccines target the virus’ ability to infect people. Getting the vaccine reduces your chances of reinfection and avoiding severe COVID-19 medical complications.

If you’ve had COVID-19, you might delay vaccination for up to 60 days after your diagnosis. Re-infection during this period is uncommon.

Will there be additional vaccines for COVID-19?

Flu and other vaccines

  • Health experts do not currently recommend getting the flu shot and the COVID-19 vaccine on the same day. Clinical trials for the COVID-19 vaccines did not test the safety of getting the flu vaccine on the same day. Talk to your health care provider about how far apart they should be spaced.
  • The COVID-19 vaccine does not take the place of other vaccines. It is a good idea to be up-to-date on pneumonia and flu vaccines in addition to COVID-19. Please talk to your health care provider about which vaccines are recommended for you.