Three COVID-19 vaccines are currently approved by for distribution in the United States: Pfizer, Moderna and Janssen/Johnson & Johnson.

As distribution begins to open up across the state of Florida, it may lead many of us to wonder: Does it matter which vaccine I get?

The short answer is no. They all prevent severe disease and death by teaching our immune systems how to recognize and fight the virus that causes COVID-19.

The short answer is no. They all prevent severe disease and death by teaching our immune systems how to recognize and fight the virus that causes COVID-19. Furthermore, the Centers for Disease Control and Prevention stresses that COVID-19 vaccination is an important tool to help us get back to normal.

“In order for us to regain normalcy we need to achieve what is called ‘herd immunity’ ” says Jane Gibson, chair of clinical sciences and professor of pathology at UCF’s College of Medicine. “Herd immunity means that the chances of the disease spreading among individuals is lowered because the majority of the population — in this case estimated to be approximately 70-80% — will have antibodies. You can achieve herd immunity naturally, which may involve more rounds of infection surges and many more deaths, or we can achieve it through vaccination, which is why getting any one of these three vaccines is critical.”

How does the Janseen/Johnson & Johnson vaccine differ from the Pfzier and Moderna vaccines?

The CDC explains typically, most vaccines — like the Janseen/Johnson & Johnson COVID-19 vaccine — use weakened or inactivated versions or components of the disease-causing pathogen to stimulate the body’s immune response to create antibodies. In contrast, mRNA vaccines — like Pfzier and Moderna’s COVID-19 vaccines — take advantage of the process that cells use to make proteins in order to trigger an immune response and build immunity to the virus that causes COVID-19. Although this technology is new, mRNA vaccines have been studied for more than a decade. Like all vaccines, COVID-19 mRNA vaccines have been rigorously tested for safety before being authorized for use in the United States.

How are each of the vaccines administered?

Pfzier: 2 shots, 21 days apart

Moderna: 2 shots, 28 days apart

Janssen / Johnson & Johnson: 1 shot

Why the difference in number of shots or number of days in between? The dosages and schedule are derived from the clinical trial process.

“Those studies informed the dosing regimens which were used in the initial clinical trials and may differ among vaccines based on their efficacy in animals and performance in laboratory studies to determine if the vaccine produced neutralizing antibodies,” Gibson says. “Future clinical trials with these vaccines may offer additional modifications to dosing recommendations based on larger pool of data researchers are tracking as the vaccines are more widely distributed.”

Is one vaccine more effective than another?

Pfizer: 95% efficacy in preventing COVID-19 in those without prior infection.

Moderna: 94.1% effective at preventing symptomatic infection in people with no evidence of previous COVID-19 infection.

Janssen/Johnson & Johnson: 72% overall efficacy and 86% efficacy against severe disease in the U.S.

Of note, mRNA trials were held and the efficacies of Pfizer and Moderna’s vaccines were reported before more contagious variants of the virus began to spread.

“Although there have been no head-to-head trials to compare the vaccines to each other, the reported efficacies of each of the COVID vaccines determined during clinical trials appear to be better than recent flu vaccines,” Gibson says. “For example, as cited in the 2021 CDC Morbidity and Mortality Weekly Report, the current influenza vaccine has been 45% effective overall against 2019-20 seasonal influenza A and B viruses.”

When am I considered fully vaccinated?

According to the CDC, people are considered fully vaccinated:

  • 2 weeks after their second dose in a 2-dose series, like the Pfizer or Moderna vaccines
  • 2 weeks after a single-dose vaccine, like Janssen/Johnson & Johnson’s vaccine

If it has been less than two weeks since your shot, or if you still need to get your second dose, you are NOT fully protected. Furthermore, experts are still monitoring whether getting a COVID-19 vaccine will prevent you from spreading the virus that causes COVID-19 to other people, even if you don’t get sick yourself.

It’s important for everyone to continue using all the tools available to help stop this pandemic, so that means wearing a face covering, physical distancing, washing hands frequently and avoiding large crowds should still be a part of your daily life right now.

Once you are fully vaccinated, the CDC recently OK’d:

  • Gathering indoors with fully vaccinated people without wearing a mask.
  • Gathering indoors with unvaccinated people from one other household (for example, visiting with relatives who all live together) without masks, unless any of those people or anyone they live with has an increased risk for severe illness from COVID-19.
  • If you’ve been around someone who has COVID-19, you do not need to stay away from others or get tested unless you have symptoms.

Where can I get vaccinated?

College educators and staff of all ages are eligible to receive the vaccine at the Orange County Convention Center and other sites within the county. UCF encourages all eligible faculty and staff to take advantage of sites offering vaccines.

The Orange County Convention Center is a drive-thru site that requires appointments. For more information on making appointments and to see other locations where educators are eligible to receive the vaccine, including a federally run walk-up site at Valencia College’s West Campus, go to Orange County’s Vaccine Information page.

Providers in other counties also are offering the vaccine to residents who qualify, and members of the UCF community may elect to receive their vaccinations through one of those offerings if they are eligible.

More information about why vaccines are important and what to expect at your appointment is being shared here. Those with questions can email