COVID-19 vaccine Q&A

A U.S. Navy corpsman administers a U.S. Marine with the Pfizer-BioNTech COVID-19 Vaccine on Camp Lejeune, N.C., Jan. 15.

To allay the concerns some people may have about receiving the COVID-19 vaccine, the following questions and answers are being printed following interviews with Dr. Akram Sadaka, director of Public Health with Naval Health Clinic Patuxent River; Dr. Patricia Bray, public health emergency officer for NAS Patuxent River and Dr. Meena Brewster, St. Mary’s County health officer.

Q: What are the types of COVID vaccines, and how do they work?

DR. BRAY: The Pfizer and Moderna vaccines prevent infection from SARS-CoV-2, the virus that causes COVID-19. These vaccines are messenger RNA (mRNA) vaccines. According to the Centers for Disease Control and Prevention (CDC), mRNA vaccines teach our cells how to make a protein that triggers an immune response inside our bodies. That response, which produces antibodies, is what protects us from getting infected if COVID-19 enters our bodies.

They do not contain the live virus that causes COVID-19. You can’t get COVID-19 from the vaccine. They don’t affect or interact with our DNA in any way. Each of them has gone through the same safety tests and meets the same standards as any other vaccines produced through the years. There is a system in place that allows the CDC to watch for safety issues and make sure the vaccines stay safe. The vaccine does not give you COVID. It gives instructions for our cells to make a harmless piece called a “spike protein.” The spike protein is found on the surface of the virus that causes COVID-19.

Vaccines are given in the upper arm muscle. Once the instructions are inside the immune cells, the cells use them to make the protein piece. After the protein piece is made, the cell breaks down the instructions and gets rid of them. Our immune system recognizes that the protein doesn’t belong there and begins building an immune response and making antibodies, mimicking what happens in natural infection against COVID-19. That’s why sometimes people might feel a little under the weather: it’s the vaccine at work.

This process means that our bodies have learned how to protect against future infection. The benefit of vaccines is those vaccinated gain this protection without ever having to risk the serious consequences of getting sick with COVID-19. It feels just like a typical shot. The needle is very thin and the process takes less than one minute from swab to finish.”

Q: A big question for many is how our organizations are rolling out the COVID vaccine to our populations. How is Pax River implementing the DoD COVID vaccination plan?

DR. SADAKA: Pax River is following the DoD’s standardized and coordinated strategy for prioritizing, distributing, and administering a COVID-19 vaccine through a phased approach to military as well as all mission-essential Department of Defense civilian employees and other personnel performing mission essential functions, including healthcare, emergency services personnel, and critical support.

Prioritization will focus on those providing direct medical care, maintaining essential national security and installation functions, deploying forces, and those at the highest risk for developing severe illness from COVID-19, before other members of the DoD population. We are updating our [clinic] Facebook page and website daily with who we are seeing and who we are not yet seeing, so there isn’t any confusion.

The distribution process is phase driven to safely protect DoD personnel from COVID-19 as quickly as possible.

Q: And how is the county rolling out their vaccine plan?

DR. BREWSTER: St. Mary’s County is coordinating with state and local partners to ensure a safe and orderly plan for distribution, particularly for vulnerable and at-risk populations.

The county is in Phase 1a – vaccinating heath care workers, residents and staff of long-term care facilities, and first responders, among others. The county is ready to move in to Phase 1b, pending state approval, for additional first responders and medical personnel and other occupational categories.

St. Mary’s County has been distributing these via mass-vaccine clinics through community partners to effectively distribute the vaccine appropriately.

Q: Another question on a lot of people’s minds is what some of the long term effects of the vaccine may be. Can you tell us about that?

DR. SADAKA: The short answer is we don’t know what, if any, long term effects of the vaccine are. Conversely, we don’t know all of the long term effects of COVID on subjects who survived it, but we have already seen cardiac, pulmonary, neurological, and immunological complications from COVID disease in those who survived.

The vaccines may cause side effects in some people, like sore muscles, feeling tired or mild fever. For most people, these side effects will last no more than a day or two. Having these side effects doesn’t mean you have COVID-19. If you have questions about how you’re feeling after your shot, contact your provider or call the Military Health System Nurse Advice Line [at 1-800-TRICARE (874-2273), option 1.]

It’s rare, but if you have a severe allergic reaction, call 911 or go to your nearest emergency room. A severe allergic reaction would usually occur within a few minutes to one hour after getting a dose of the vaccine.

Q: Can a vaccinated individual transmit to a non-vaccinated individual?

DR. SADAKA: Everyone should voluntarily receive the vaccine when it is available to them because duration of immunity following COVID-19 infection is unknown, and the vaccine may be effective in protecting previously infected people.

The vaccine recipient can still be exposed to the virus, become a host without becoming ill and perhaps transmit to others. This type of asymptomatic transmission is more insidious and difficult to control.

I would say the “reasonable degree of probability” applies to our scientific understanding of the vaccine’s mechanism of action, but cannot say the same based on actual observed transmission events.

We don’t yet know empirically whether vaccination may have an effect on transmissibility and/or infectivity to others—will have to wait for actual case studies and epidemiologic evidence to emerge.

Q: If someone has been ill with COVID-19, do they still need to get the vaccine?

DR. BRAY: Yes, because duration of immunity following COVID-19 infection is unknown, and the vaccine may be effective in protecting previously infected people.

Q: Are face coverings and physical distancing still necessary with a COVID vaccine?

DR. BRAY: Yes. The intent of the vaccine is to prevent illness in the vaccine recipient. We will still need to wear cloth face coverings and practice physical distancing to limit the spread of the virus. Additionally, we will not have enough vaccine initially to vaccinate everyone who wants the vaccine and COVID-19 pandemic risks will continue. So we will continue to recommend wearing masks and practicing physical distancing, for everyone, until pandemic risk of COVID-19 is substantially reduced.

Q: Is it still important to get the flu shot too?

DR. BRAY: Yes, it is very important to get the influenza vaccine, particularly this season when both influenza viruses and COVID-19 will infect people. The seasonal flu, combined with the COVID-19 pandemic, could overburden the health care system, strain testing capacity, and increase the risk of catching both diseases at once. Getting the flu shot is highly recommended.

Q: How long is the vaccine good for?

DR. BREWSTER: This is unknown and is precisely why we cannot make changes to current preventive measures. This question is being actively studied formally by the vaccine manufacturer and informally by sites across the country.

Q: Why should we receive the first-available vaccine when there are several other vaccines still in trials?

DR. SADAKA: The [Advisory Committee on Immunization Practices] guidance was to give the vaccine to people who were most vulnerable, including people who are most at risk. Vaccinated people will be protecting themselves, as well as their families and all people with whom they interact. Evaluation of the first-available vaccine will continue, even after its pre-licensure release. The release of other vaccines cannot be fully predicted, so people who are offered the first-available vaccine will be encouraged to receive this vaccine.

Q: Should workers who had COVID-19 receive another test before returning to work?

DR. SADAKA: No, a negative test following illness is not necessary, with very rare exceptions. In fact, another test should not be ordered in the three months following a positive test, because viral fragments that are noninfectious are likely to cause a falsely positive test result.

Q: When will we achieve herd immunity?

DR. BREWSTER: We anticipate there will eventually be herd immunity but until we have more information we cannot draw conclusions. Furthermore it is unknown how long herd immunity will last – we don’t know if this vaccine will be an annual requirement resulting in the need to vaccinate every year to maintain individual and herd immunity.

Q: Will the vaccine be mandatory for DoD personnel?

DR. BRAY: When formally licensed by the FDA, the DoD may require a vaccine for military personnel or personnel in specific fields, as is the case for the influenza vaccine.

NOTE: NAS Patuxent River personnel should follow the installation’s social media feeds for continuing news regarding the COVID-19 vaccine. Find ongoing information at and on Twitter at @NASPaxRiverPAO. In the community, residents can sign up for press release notices at