Frequently Asked Questions: The COVID-19 Vaccine

Updated 1/18/2021

Over the last few weeks, we’ve heard a lot about vaccines for the virus that causes COVID-19. There are a lot of questions about how these vaccines were developed, how they work, and if they are safe.

Glenn F. Rall, PhD, a virologist and Fox Chase’s Chief Academic Officer, answers some of the most common questions we’ve heard about the COVID-19 vaccine:

What is Emergency Use Authorization (EUA) and what does it have to do with the COVID-19 vaccine?

During a public health emergency like a pandemic, the U.S. Food and Drug Administration (FDA) may allow unapproved medical products (such as vaccines) to be used in an emergency to diagnose, treat, or prevent serious or life-threatening diseases when there are no adequate, approved, and available alternatives. If the evidence strongly suggests that patients have benefited from the medical product in clinical trials, and that the drugs or vaccines are safe, the agency can issue an EUA to make it available.

Two drug manufacturers – Pfizer/BioNTech and Moderna – have announced extremely positive early results from their COVID-19 vaccine trials. Current data from these manufacturers strongly indicate that both vaccines are safe and effective, and both companies have shared their data with the FDA. EUA approval for both of these vaccines has made them immediately available while the FDA continues to review data prior to official approval.

When will the COVID-19 vaccine become available?

Both the Pfizer/BioNTech and Moderna vaccines have been granted EUA. Over a dozen other drug companies are also conducting COVID-19 vaccine trials, and their vaccines could also be available in the coming months. At least two other companies have vaccines in Phase 3 trials and could be approved soon.

Who will be eligible for the vaccine?

Public health officials are overseeing allocation of the vaccines in our region, and a phased approach to distribution has already been adopted. The vaccine has been made available to those who are at an elevated risk for COVID-19 exposure, including nursing and physician staff serving in COVID-19 units and Emergency Departments, respiratory and physical therapists, infection control practitioners, environmental services staff serving in COVID-19 units, and other healthcare providers.Preparation is underway to begin vaccination of those who are at risk for severe illness from COVID-19 due to underlying medical conditions (such as some cancer patients) as well as other groups who continue to be at high risk for COVID-19 exposure. Vaccine distribution is being managed at the state level and in the case of Philadelphia, by the City of Philadelphia. For more information about the phased approach to vaccination, please visit your state's COVID-19 website.

Pennsylvania COVID-19 Vaccine Information

Are these vaccines effective?

Data from research studies shows that both the Pfizer and Moderna vaccines are 95% effective in preventing individuals from getting COVID-19. The studies compared how many in the vaccinated group and the placebo group went on to develop the disease; nearly all the cases of COVID-19 were within the placebo group, and of the small number of cases in the vaccinated group, none were clinically serious. The vaccines are effective in preventing COVID-19 infection, as well as severe symptoms in those who are already infected.

Are these vaccines safe?

Before the FDA grants EUA, the safety and efficacy of the vaccines are reviewed by panels of independent experts retained by the drug companies, FDA scientific staff, and an independent panel of experts convened by the FDA. After treatment of tens of thousands of volunteers in the clinical trials, there are no reported safety concerns for either of these vaccines.

The Pfizer and Moderna vaccines use a gene from the virus, not the whole virus. For this reason, it is impossible to “catch” coronavirus from the vaccines. With an abundance of caution, even after EUA is granted, The Centers for Disease Control and Prevention (CDC) and the FDA will continue to monitor individuals who have received the vaccine to ensure that no rare safety issues occur.

Are there side effects?

Both the Pfizer and Moderna vaccines require two doses: an initial vaccination and then a second shot three or four weeks later. Both doses are required to ensure full protection against the virus that causes COVID-19, and all vaccine recipients are strongly reminded to get both doses.

As with other vaccines, some people have experienced modest side effects consistent with immune responses. It is normal to experience some arm soreness after receiving the vaccine, and some people may experience additional side effects like fatigue, fever, muscle pain, chills, or headache.

The Food and Drug Administration and other organizations have recommended not premedicating with an NSAID (non-aspirin pain reducer) due to the theoretical possibility that it could decrease the immune response to the vaccine, but once a patient begins experiencing side effects, use of an NSAID is acceptable.

Is it safe to receive a vaccine during cancer treatment?

Yes. We know that the COVID-19 vaccinations available for use in the United States are both safe and highly effective. No medical professional group or society has restricted the use of any of the currently available vaccines for cancer patients. However, every cancer patient is different, and the first step to getting vaccinated is talking with your oncologist about your cancer and treatment to determine the right immunization plan for you.

Is Fox Chase currently offering the vaccine?

Not at this time. Logistics for how the COVID-19 vaccine will be distributed to patients (once healthcare workers have been vaccinated) are still in development. A plan for Fox Chase and the entire Temple University Health System is being discussed in conjunction with the City of Philadelphia government, which is responsible for the distribution of the vaccine doses to all city hospitals. We will be sure to keep our patients updated as these details unfold. Updates and details about vaccine availability will be posted on this website and on the myTempleHealth platform.

Can I have a letter stating that I am at high-risk so my primary care provider will administer the COVID-19 vaccine to me when it is available?

Any letter would have to come from an individual provider. Not all cancer patients are considered high risk. We recommend that you discuss your risk level and the right immunization plan for you with your oncologist.

What’s the difference between the Moderna and Pfizer vaccines? Is one more effective than the other?

There are differences, but the differences don’t matter for the vaccine recipient. One of the differences is that the dose of RNA present in the vaccine is slightly different. The Pfizer vaccine is 30 micrograms of RNA and the Moderna vaccine is 100 micrograms. The second difference is the period of time that needs to elapse between the first and second dose. For the Pfizer vaccine, that time is 21 days and for Moderna it is 28 days. The lipids in which the RNA is encased are slightly different and storage requirements are also different. There are no other functional differences or differences in efficacy or safety.

Other vaccines in development, like the ones from AstraZeneca and J&J, don’t use messengerRNA. Are these vaccines better? Should I wait for them?

No, these vaccines are not better, and you should not wait for them. There are other vaccines that may be coming out but haven’t yet. They are different but they’re not necessarily better. All the data we have suggests that they are safe and effective, as much so as the Moderna and Pfizer vaccines.

As vaccine administration continues, what precautions are still reasonable to take (masks, social distancing, etc.)?

The vaccines have been shown to prevent coronavirus disease, meaning symptomatic infection and severe coronavirus disease. We don’t know if it prevents asymptomatic infection. Once you’re vaccinated, you may feel safer, but you may still be a carrier and could still transmit it to someone. We cannot stop using masks and staying six feet apart. All the precautions in place need to remain in place.

Where can I get more information?

We understand that there are many questions about these vaccines, and we encourage you to consult the following websites for additional information:

While there is a lot of information coming out about these vaccines, it is important to seek out expert resources when doing your research.

If you are a Fox Chase patient and have questions about COVID-19 or your eligibility for the vaccine, we recommend speaking to your care team.

You can find more information for cancer patients and survivors and the COVID-19 vaccine here.

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