Vaccine FAQs
About the Vaccine
The two COVID-19 vaccines submitted to the FDA for emergency use authorization – one from Pfizer/BioNTech and one from Moderna – use what’s called messenger RNA (mRNA), which in this case is a synthetic material that carries the genetic code used to make the SARS-CoV-2 spike protein. The spike is the part of the virus that attaches to human cells. The mRNA is showing your immune system a part of the virus, so that when your body encounters the whole virus in real-life, it recognizes the invader and is able to mount a quick immune response, activating antibodies (B and T-cells) to fight it. That’s how the mRNA vaccines work.
While many vaccines use a weakened or inactive version of the virus to create an immune response, mRNA doesn’t contain any live virus, so there is no risk of it causing disease. The mRNA also never enters the nucleus of the cell and does not affect a person’s DNA. The body also contains enzymes that break down mRNA quickly, reducing chances for long-range side effects.
Vaccines using mRNA are new but the technology has been around for decades and has been used in treatments for other diseases such as cancer and cystic fibrosis. Another benefit to mRNA is that manufacturing large quantities of it is easier because scientists don’t have to grow live virus in a lab to make the vaccine. Pfizer and Moderna have said they expect to deliver between 50 million and 100 million doses of their vaccines by early 2021.
Our Scientific Review Committee here at UT Southwestern looked at the Pfizer and Moderna trials to identify any differences between the vaccines and determine if there were groups who should receive one over the other.
We found these trials were very similar, in both efficacy and side effects. The unanimous vote of the Scientific Review Committee is to get whichever vaccine you have access to first. They are both safe and efficacious.
No tissue or cell lines from fetal tissue were used in the design or production of the Pfizer or Moderna mRNA COVID-19 vaccines. The mRNA technology allows for the vaccine to be made synthetically rather than requiring virus to be grown in cell lines.
The first shot triggers the immune response, and the second one, often called a “booster,” primes the body to memorize the virus so it will immediately fight it off in the future. Many effective vaccines require two shots or boosters, such as those for tetanus, shingles, and MMR.
The COVID-19 vaccines each require a second shot (21 days later for Pfizer, 28 for Moderna). If you skip the second shot, it’s less likely you’ll develop full immunity – not to mention a valuable dose of vaccine will be wasted. Health care providers will try to make the appointments as convenient as possible for patients, setting up both the initial and booster shot dates at the same time and providing reminders through email or phone alerts, in addition to notices on patient portals such as MyChart.
In Phase 3 clinical trials involving thousands of people, both the Pfizer and Moderna vaccines produced effectiveness rates near 95%. For context, the FDA had suggested a coronavirus vaccine would need to be at least 50% effective to earn emergency authorization. Most experts had hoped for 70%. The early results put COVID-19 vaccines in the efficacy realm of shots for chickenpox (92%), measles-mumps-rubella (97%), and polio (99%).
UT Southwestern’s Vaccine Science Review Committee is independently reviewing clinical trial data of the vaccine candidates and carefully analyzing all findings prior to distributing the vaccine to UTSW personnel and patients.
The most commonly reported side effects from the Pfizer-BioNTech COVID-19 vaccine include pain at the injection site, fatigue, headache, muscle pain, chills, joint pain, and fever. During clinical trials, reactions were more common after the second dose of the vaccine than the first.
Mild to moderate side effects like swollen lymph nodes can be expected as the body responds to the vaccine and activates the immune system. The causal relationship between the vaccine and other reactions like Bell’s palsy is less certain because the number of cases reported during trials was small and not more than found in the general population. Serious side effects from the vaccine are very rare, less than 0.5 percent, but there is a remote chance that the Pfizer-BioNTech COVID-19 vaccine could cause a severe allergic reaction such as a rash, dizziness, or difficulty breathing.
Overall, the vaccine has a favorable safety profile. According to the U.S. Food and Drug Administration, the Centers for Disease Control and Prevention, and UT Southwestern’s Vaccine Science Review Committee, the known and potential benefits outweigh the known and potential risks of the vaccine’s use.
This is something that is rapidly at work and there will be more information in a couple of days, and certainly in the next coming weeks. Viruses do evolve. Mutations do occur. We see this with RNA viruses, because the enzyme that copies the RNA is prone to error.
The vast majority of those mutations are what we call neutral - they don't really have an impact on the fitness of the virus, the ability to infect. We have, since the beginning of this pandemic, characterized several mutations, and while a few of them in the lab setting have shown the ability to infect cells at a greater level, this hasn't translated into any meaningful impact on the ability to evade vaccine immunity.
Now, what happened in the United Kingdom is that there is an entity, the COVID-19 genomics consortium in the U.K., which sequences these viruses on a regular basis and looks for mutations. At the time that there was a seasonal surge of the virus in Southern England, they picked up a new lineage, which had 17 mutations. While there is biological interest in this, we don't yet know the clinical significance of it, and that is going to be the focus of study for the next couple of days and weeks.
Two things to consider:
- Vaccine-induced immunity to the spike protein through the vaccines that we have will generate antibody responses that are to several parts of the spike protein, not just a few amino acids. In practice, it would take a series of cumulative mutations over a long period of time to start to impact vaccine immunity.
- Regardless or not of whether we find out this variant lineage to have a higher transmutability, it just underscores the importance of all those non-pharmacological measures that we should be doing, wearing masks, preventing transmission, social distancing, and hygiene. That's something that we can do right now.
The bottom line is this should not distract us from getting vaccinated. We should continue to get vaccinated, and we should continue to use those non-pharmacological measures.
Vaccine Distribution
Rigorous work across UT Southwestern ensured we were ready as soon as the U.S. Food and Drug Administration provided Emergency Use Authorization (EUA) of a SARS-CoV-2 vaccine. There were three important dimensions of this work focused on the safety, equity, effectiveness, and efficiency of our vaccine distribution.
First, a multidisciplinary team – comprised of immunologists, infectious disease experts, epidemiologists, ethicists, and other key stakeholders – convened several weeks ago to consider our approach to the prioritization of the vaccine when initial supplies are limited. Our policies and allocation strategies have been informed by advisories from national organizations, including the National Academy of Medicine (NAM), the Centers for Disease Control and Prevention (CDC), and the FDA, and similarly prioritize early vaccination of health care workers and other employees in direct contact with COVID-19 patients or infectious particles, as well as first responders and those who play pivotal roles in supporting their activities and operations.
Second, UTSW established a Vaccine Science Review Committee to independently review clinical trial data of the vaccine candidates. We are confident in the FDA’s evaluation, but we also feel an obligation to carefully review the findings to better guide recommendations to the campus community and our patients as we prepare to distribute the vaccine.
Third, a team of UTSW health system leaders has been focused on ensuring operational readiness for rapid and efficient distribution of the vaccine. Should the FDA authorize emergency use of the vaccine – and our scientific workgroup endorse it – we are prepared to administer the vaccine almost immediately upon receipt of our first shipment and guided by our prioritization principles.
UT Southwestern is receiving both the Moderna and the Pfizer-BioNTech vaccines. Both vaccines underwent the same rigorous review. Each requires two doses. As far as which vaccine to get, they are extremely similar, and their degrees of safety and effectiveness are nearly identical. UT Southwestern, along with the U.S. Food and Drug Administration and Centers for Disease Control and Prevention, advises that you receive the first vaccine available to you and treats them as equivalents.
The initial phases of the vaccine distribution are focused on people who are providing front-line health care, or those supporting them. We currently are scheduling appointments for phases 1a.1 through 1a.6.
The decisions on when to release to the different phases are considered as more vaccine comes in, in discussions with the top leadership of the organization. We expect to move through phases as more vaccine arrives.
In terms of patients and the general public, a lot of the Moderna vaccine that is being shipped this week is going to pharmacy chains. The state and federal government have contracted with CVS and Walgreens to vaccinate people in nursing homes. We also anticipate that a lot of the vaccination of the general public will be done through these retail pharmacy chains. So this is not just a hospital effort, it's going to be a societal effort.
Because supplies will be limited initially, we must ensure equitable distribution for the greatest benefit so that we can continue to provide the very best care for our patients and each other. We will use MyChart to notify you when vaccines become available, based on your UT Southwestern role. If you do not have a MyChart account, you will receive a message (to your work email address) with a link and instructions for activating one.
Members of the UT Southwestern community are strongly encouraged to take advantage of access to the vaccine as it becomes available to you. However, to be clear, the decision to receive the vaccine is an individual one and not required by UT Southwestern.
The initial 5,850 shipment just represents the first dose. Pfizer is going to ship us 5,850 vials three weeks from now to account for that second dose. As some of you may have read in the media accounts, there was some overfill in the first box that allowed us to get extra doses out of that. It was actually a fortuitous event that we were allowed to vaccinate more people in the early phases than we'd initially planned.
The process for being scheduled for the second dose will be very similar to the first dose. When we receive notice of shipment of the second dose, we will create slots to be scheduled and you will receive a MyChart notification and an email that the slots are available. At that point, you can schedule a time that’s convenient for you to come get your second dose.
The Centers for Disease Control (CDC) announced that fully vaccinated people can resume activities without wearing a mask or physically distancing, except where required by federal, state, local, tribal, or territorial laws, rules, and regulations, including local business and workplace guidance. UT Southwestern will continue to strongly encourage – but no longer require – the wearing of masks by students, faculty, staff, and guests in nonclinical areas of our campus. However, wearing a mask is still required within William P. Clements Jr. University Hospital and all other clinical facilities.
Yes, you can. The available trials so far show that the vaccine is effective at reducing symptomatic COVID-19 by up to 95%. We do not yet know how much effect the vaccine has at reducing asymptomatic disease or transmission. This is why PPE requirements and adherence to protective measures such as masking and physical distancing will still be necessary even after vaccination.
Yes. While members of the UT Southwestern community are encouraged to take advantage of access to the vaccine as it becomes available to you, the decision to receive the vaccine is an individual one and not required by UT Southwestern. Individuals have the right to decline vaccination, and that initial declination is not binding. If an individual later decides to receive the vaccine, their priority will remain within the phase they were first assigned.
Even if you are not at an increased risk of severe complications, there is no way to predict how COVID-19 will affect you. Infections can range from asymptomatic to mild or severe cases and even death. COVID-19 vaccination helps protect you by creating an antibody response that prevents infection from the disease.
The 70 percent threshold that gets you the so-called herd immunity is a very dynamic estimate. One of the challenges we have is that, as is usual with many viruses, we don't have that immune correlate of protection. That is, what measure of the immune system correlates to protection.
Natural infection is not the way that we want to induce herd immunity. We've seen the disastrous consequences and toll of this for several months. Vaccine-induced herd immunity is the way forward. Now, how this will take shape is going to be an evolving question in the next several months.
The 70 percent is based on the distribution and how long it will take to get vaccines. It is also dependent upon population uptake.
Vaccine Safety
There is a well-established testing and clinical trial protocol that must be followed for the FDA to consider approving a vaccine. For these COVID-19 vaccines, research and development, clinical trials, manufacturing, and strategies for distribution overlapped to accelerate the process, but no steps were skipped.
An independent and transparent monitoring board of experts reviews the trial data, and career scientists evaluate it at the FDA. Eventually, all the clinical trial information will be published in a peer-reviewed journal. Safety was not sacrificed for speed.
There is no evidence or reason to think COVID-19 vaccines affect fertility, despite some claims to the contrary circulating on the internet. Those reports are rooted in the theory that because the SARS-CoV-2 spike protein resembles the syncytin-1 protein, which is crucial for formation of the placenta, the COVID-19 vaccines might prompt an immune response that targets the placenta protein. But virologists say the two proteins are completely unrelated and not similar enough to confuse antibodies that attack the virus.
Pregnant and breastfeeding patients were excluded from trials for the novel coronavirus vaccination. There is no data on the safety and effectiveness of COVID-19 vaccines in this population.
However, the Food and Drug Administration (FDA) approved the emergency use authorization of the Pfizer-BioNTech vaccine for anyone 16 and older. This means pregnant and breastfeeding women may opt to get the vaccine.
We recommend that patients have a personal discussion with their obstetric care provider. Things to consider include whether you have any other medical condition that makes a COVID-19 infection more dangerous for you and how compliant you can be with the precautions that reduce the risk of infection.
The clinical trials conducted so far have focused on the vaccines’ safety and effectiveness in adults and children over 16 years old. COVID-19 vaccine trials for younger adolescents, starting at 12 years old, are underway, and there is the possibility of children being able to receive the vaccine in 2021.
Yes, vaccination is still recommended even if you have already contracted COVID-19. Data from clinical trials suggest vaccination is safe and likely effective in people regardless of history of prior symptomatic or asymptomatic SARS-CoV-2 infection. The CDC recommends that people actively experiencing symptoms of COVID-19 should wait to be vaccinated until they recover from acute illness and meet the criteria to discontinue isolation.
True severe allergic reactions to vaccines historically are very rare. UT Southwestern is following the CDC’s recommendations regarding potential allergic reactions. One recommendation is for each patient to remain in observation for 15 minutes after receiving the vaccine.
For those who have a history of allergies to food, pets, environment, or oral medications, it’s recommended that you can still get the vaccine with the usual 15-minute observation period.
For those who have had a severe allergic reaction to a non-COVID vaccine or an intravenous medication or injectable in the past, it's recommended that you discuss with your provider before getting the vaccine. In the vast majority of cases, you can still get this vaccine, but with an extended 30-minute observation period.
For those who have a history of a severe allergic reaction to one of the components of the COVID-19 vaccines, such polyethylene glycol or polysorbate, it’s recommended that you do NOT get one of the currently available COVID-19 vaccines. Also, if you have a severe or immediate allergic reaction to the first dose of a COVID-19 vaccine, you should NOT get the second dose of the COVID-19 vaccine until you discuss the specifics of the reaction with your provider.
As part of the phase three trials that led to authorization of both vaccines, there were some groups of patients that were excluded from these phase three trials, and one of those includes immunocompromised recipients, solid organ transplant recipients, allogenic stem cell transplant recipients, and those with some auto-immune conditions who are on immunosuppression.
Now, despite their exclusion, they are recognized as being at risk of COVID-19, in its most severe form. That’s why these groups should still be considered for vaccination. The CDC has actually designated immunocompromised patients as a high-risk population, as part of phase 1C of their rollout plan.
The first thing to consider is safety. These mRNA vaccines are not live, meaning they don't have live viral particles. They showed excellent safety profile in the trials. There's no reason to really suspect that there's going to be new safety concerns that come up in those populations. What needs to happen is a very careful discussion with the patient to really understand that, in the vast majority of patients, the benefits of vaccination are going to override any theoretical risks.
Shared decision making is important because, in these immunocompromised patients, we don't yet know what type of immune responses they're going to mount to the vaccine, and how that will translate into efficacy. A necessary part of that discussion is the reminder to use those non-pharmacological measures of prevention. There may also be cases in which vaccination timing may need to be altered depending on what types of chemotherapy or immunosuppression the patient is getting, to try and improve the immune response as much as you can.
There are several disease societies coming out with guidelines pertaining to immunocompromised patients, as to how to apply these vaccines. Already, the American Society of Transplantation and the National Psoriasis Foundation released initial guidance, and there will be far more societies releasing guidance in the coming weeks.
We continue to receive questions from across our UT Southwestern community and will expand our vaccine FAQs as answers are available. Please check back often for updates and covid-19questions@utsouthwestern.edu us with additional questions you may have.