Thursday, March 4, 2021

Your COVID-19 Vaccine Questions Answered

(Editor’s note: COVID-19 vaccination information is rapidly changing. The information contained within this article is current as of January 20).

As Pennsylvania continues to roll out plans for distribution of both the Pfizer BioNTech and Moderna COVID-19 vaccines, many questions remain regarding the vaccines themselves, as well as availability within our local communities. Below is a list of questions and answers to some of the most common inquires that I receive as a physician with Mount Nittany Physician Group that I hope will help to arm readers with the information they need.

Q: Why should I get the COVID-19 vaccine?

A: The COVID-19 vaccines are tremendous scientific achievements and are the best way for us to return to normal life. However, many people are nervous about getting the new vaccine. These vaccines are both safe and effective, as I’ll outline below.

Q: What is RNA and how does the vaccine work?

A: RNA is a type of nucleic acid that SARS-CoV-2 uses to carry its genetic information. It is a blueprint to produce proteins that form the virus particle. Both of the FDA-approved COVID-19 vaccines contain a small piece of SARS-CoV-2 RNA encased in a lipid particle. When injected into the body, these particles are taken up by immune cells, the viral spike protein is produced, and our immune system produces antibodies and other immune cells that specifically recognize it. This process mirrors exactly what happens when the virus infects our body, but the vaccine cannot cause infection as it does not contain the actual virus. A second booster vaccine makes the immune response even stronger. If we are exposed to the virus, our immune system now has all the tools needed to rapidly clear it.

Q: What is herd immunity and how does it relate to the vaccine?

A: Herd immunity refers to how many people in the population need to be immune to the virus to prevent it from being spread. The more contagious the virus, the more people need to have immunity to prevent transmission. For COVID-19, 50 to 70 percent of the population needs to have immunity to achieve herd immunity. This number may change as we learn more about the virus, and it may be higher if more contagious strains emerge, such as the U.K. variant, now beginning to appear throughout the United States.

Some people have proposed letting COVID-19 run its course to achieve herd immunity, but this could result in more than 2 million deaths in the U.S. The only safe and effective way to achieve herd immunity is through vaccination, and we need to vaccinate the majority of the population to be successful.  

Q: It seems like these vaccines were rushed to be developed. How do I know that they are really safe?

A: Many people are concerned about vaccines in general, as there are misconceptions that these are not safe because they are artificial, lab-made constructs. Because this vaccine mimics exactly what the virus does in our body, but in a way that infection is not possible, this is actually the most natural way to produce immunity. The vaccines were built on technology that has been used by scientists for over a decade, and were able to be developed because there was an unprecedented amount of global research devoted to this virus.

We have data from well-conducted, large studies (with more than 70,000 total participants) as well as vaccinations from millions that have already received this vaccine worldwide. As almost all adverse vaccine reactions occur within a few days to eight weeks of injection, we have enough data to prove that the vaccine is safe.

Q: What are the side effects?

A: The most common side effect is a sore arm for 24 to 48 hours. Some people can develop a fever, swollen lymph nodes, generalized muscle pain, or fatigue. These side effects are generally mild and not unexpected. They indicate that our immune system is activated.

Q: I have a history of food or drug allergy. Should I be worried about an allergic reaction to the vaccines?

A: The risk of allergic reaction is very low. Twenty one allergic reactions have occurred in the first 1.85 million vaccine doses (about one in 100,000 injections). In general, patients with a history of previous allergic reactions to foods or medications may safely receive the vaccine, but would need to be observed for 30 minutes after administration. The suspected allergen is polyethylene glycol, a common ingredient in many different medications, household products, and some laxatives. Patients with an allergy to polyethylene glycol can be evaluated and tested in our allergy clinic.

Q: I am healthy and have a low risk of severe COVID-19. Why should I be vaccinated?

A: COVID-19 is unpredictable and can be severe in any age group. Even if you get a mild infection, you will infect other people. The vaccine protects not only you, but your family, people with immune deficiencies or cancer, and others who may not be able to mount a response to the vaccine. We all want to go back to pre-pandemic life, but things cannot go back to normal if only some people choose to be vaccinated. Everyone needs to do their part to not only be vaccinated, but to encourage their family and friends to do the same.

Q: When will the vaccines be available to the general public in Centre County?

A: As most people know, COVID-19 vaccines are being distributed to Pennsylvanians in a phased approach. It’s important to understand that the Pennsylvania Department of Health (DOH), as the state’s public health agency, is the lead in terms of moving from one vaccination phase to the next. As information is finalized on additional vaccine allotments and the status of the DOH phased rollout process, Mount Nittany Health will keep the communities we serve informed.

DOH will continue to provide updates on where vaccines are being distributed across the commonwealth on, and Mount Nittany Health will share this information as it becomes available at

Mount Nittany Health also encourages patients to sign up for its patient portal at, an online tool where they can communicate with their provider about the COVID-19 vaccine.


Faoud Ishmael, MD, PhD, is a board certified allergy and immunology physician with Mount Nittany Physician Group Allergy & Immunology, and offers particular expertise in allergy management and testing, including testing for allergies related to foods and medicines.