The United States is implementing COVID-19 vaccine programs across the nation bringing hope for brighter days ahead. However, it also brings many questions.
UC Merced’s Director of Medical Education Dr. Thelma Hurd and staff physician Dr. Michelle Brinkop joined together to answer some common questions about the vaccines, so people can get their shots with confidence.
What COVID-19 vaccines are available now? Is there more than one type of vaccine?
Multiple companies are developing vaccines to work against SARS-CoV-19. Currently, two vaccines have been tested in large-scale trials and have been granted emergency use authorization (EUA) by the Food and Drug Administration (FDA).
- Pfizer-BioNTech mRNA vaccine
- Emergency Use Authorization (EUA) Dec. 11, 2020
- Large-scale trial (44,000 participants) showed 95 percent efficacy
- Two-dose vaccine, 21 days between doses
- Moderna mRNA vaccine
- Emergency Use Authorization (EUA) Dec. 18, 2020
- Large-scale trial (30,000 participants) showed 94 percent efficacy
- Two-dose vaccine, 28 days between doses
What is an mRNA vaccine?
There are many COVID-19 vaccines in development, the first two approved by EUA are mRNA vaccines. The Pfizer and Moderna vaccines use mRNA or messenger ribonucleic acid, to instruct your body’s cells to make a specific protein found on the surface of SARS-CoV-2, the spike protein. The spike protein is displayed on the immune cell surface, causing the immune system to produce antibodies. These antibodies are specific to SARS-CoV-2 and will help protect you if you encounter the virus later.
How confident can we be that these vaccines are safe and effective?
The new COVID-19 mRNA vaccines have gone through the same rigorous safety assessment as all vaccines before they are authorized for use. Randomized, controlled studies were done to evaluate the effectiveness of these vaccines and both vaccines showed 94 percent and 95 percent efficacy in the study populations to prevent COVID-19 and decrease the risk of severe disease. The Centers for Disease Control and Prevention (CDC), FDA and other state and federal partners continue to study the effectiveness of vaccines in real-world populations as well as to monitor safety data. Current evidence suggests both vaccines are protective and generate an immune response.
The mRNA vaccines do not contain a live virus. Therefore, a person who has been vaccinated has no risk of getting the disease from the virus. The mRNA does not interact with a person’s DNA.
What are the potential side effects of the vaccine?
Vaccines produce an immune response, and it is normal to have some mild side effects. Common side effects with mRNA vaccines may include pain, redness or swelling on the arm where you received the shot and some general fatigue, headache, body aches and chills.
Can you get COVID from the vaccine?
No. The vaccines made by Pfizer and Moderna have been made from mRNA, not the live, attenuated virus.
Does the vaccine provide immediate protection? Is that after the first dose or the second?
No. The Pfizer vaccine requires two shots given 21 days apart while the Moderna vaccines require two shots given 28 days apart. The Pfizer vaccine is only 52 percent effective after the first shot and 95 percent effective after the second shot. The Moderna vaccine is 51 percent effective after the first dose and 94 percent effective after the second does. It is very important that you receive both doses of the vaccine to have high levels of immunity.
People who receive the Pfizer vaccine are not protected until 12 days after the first dose and only reaches 52 percent effectiveness a few weeks later. Approximately seven days after receiving the second dose, the Pfizer vaccine is 95 percent effective against the virus. This means that for every 100 people who receive the vaccine, 52 will be protected after the first dose and 95 after the second dose. The Moderna vaccine is 51 percent effective 14 days after the first dose and 94 percent effective 14 days after the second dose. That is, for every 100 people who receive the Moderna vaccine 51 percent will be protected 14 days after the first dose and 94 percent will be protected 14 days after the second dose.
If someone already tested positive for COVID-19, do they need to be vaccinated?
Yes. People who have had COVID-19 infection should still get the vaccine. Natural immunity from COVID-19 is still being studied, and current CDC guidelines recommend vaccination for COVID-19. However, do not get the COVID-19 vaccination until you have recovered from the COVID-19 infection.
After getting the vaccine, do you still need to take health precautions such as wearing a mask and social distancing?
Yes. After getting the vaccine you will still need to continue to wear masks and socially distance. Based upon current knowledge, the vaccines do not prevent you from getting COVID-19. However, they decrease the number of people who will have severe COVID-19. Five percent of people who receive the vaccine will not derive any benefit from it.
Will those living on or visiting campus frequently still need to get tested regularly?
Yes. It is not yet known if the Pfizer and Moderna vaccines will prevent asymptomatic infection and transmission of the disease.
Will the vaccine provide permanent immunity, or will everyone need to get revaccinated each year, like the flu shot?
We currently do not have the answer to this question. It is anticipated that the first data regarding length of immunity following vaccination will emerge in the fall this year.
Has the campus started working on a plan to receive and roll out vaccinations to the UC Merced community? If so, what’s the plan?
Yes. UC Merced worked with Merced County Department of Public Health and UC Health to receive the vaccine and have vaccination clinics on campus. The vaccination program started today (Feb. 5); there is no cost for the vaccine.
The initial round of vaccine will go to employees who are 65+ and frontline staff, such as public safety personnel, food service employees and those supporting our campus quarantine and isolation program, in line with California’s Phase 1B Tier One guidelines. With vaccine supply limited and expectations that the state will move to an age-based prioritization approach, the initial invite to employees who meet the criteria previously listed will prioritize elder employees first. When that phase is completed, we will continue to offer vaccine to faculty and staff in accordance with the prioritization scheme established by UC Health and in alignment with state guidelines.
For important updates on campus safety precautions, resources and the latest policies and guidance, visit the Campus Ready site.
