We’re in the worst global health crisis in generations. More than 300,000 Americans and more than 1.6 million people worldwide have lost their lives to COVID-19. We desperately need to put an end to this pandemic, and now, we finally have a way to do it — vaccination.

COVID-19 vaccines from Pfizer-BioNTech and Moderna have received Food and Drug Administration (FDA) emergency use authorization (EUA) in the U.S.

Because the vaccine is currently in limited supply, those at highest risk will receive it first, starting with frontline healthcare workers and nursing home residents. As supplies increase, vaccination will expand to essential frontline workers, first responders, those with chronic medical conditions, adults over 65, and finally, the general public.

Getting the COVID-19 vaccine can help protect you and everyone around you from getting sick from COVID-19. But can you trust that it’s safe? How effective is it? Are there any side effects?

We’ll answer these questions so you can make an informed decision. Also, check the Centers for Disease Control and Prevention (CDC) for the latest information.

How does the COVID-19 vaccine work?
Vaccines work with your immune system so your body will be ready to fight the virus if you are exposed. The COVID-19 vaccine helps your body develop proteins called antibodies that make you less susceptible to the disease. 

The Pfizer-BioNtech and Moderna mRNA 1273 are mRNA vaccines. They contain the portion of mRNA that encodes the spike protein, the button on the surface of the SARS-CoV2 virus. It is not a live virus, cannot replicate itself and is quickly destroyed in the cell shortly after translation. Once the spike protein is translated by the mRNA, an immune response is elicited, resulting in production of antibodies against the spike protein. When the SARS-CoV2 spike protein is bound up by antibodies, it cannot attach to and infect human cells. 

Is the vaccine safe?
COVID-19 vaccines in the U.S. are authorized after meeting rigorous scientific standards for safety. The first authorized COVID-19 vaccine, manufactured by Pfizer-BioNTech, was studied in more than 40,000 people, and 30,000 people were studied in the Moderna vaccine, to ensure they meet safety standards. The FDA will continue to monitor the safety and effectiveness of authorized vaccines through ongoing clinical trials and vaccination data.

The vaccine is so new, how can I be sure about its safety?
While COVID-19 vaccines are being developed more quickly than we typically see, scientists are relying on a decade of research to help speed the process without a need to cut corners. The vaccines are being tested in large clinical trials to make sure they meet safety standards. The CDC developed an additional layer of safety monitoring called V-safe, an after-vaccination health checker for COVID-19 vaccine recipients to rapidly detect any safety issues.

How was the vaccine approved so quickly?
The FDA is responsible for approving drugs and vaccines in the U.S. In December 2020, the FDA issued EUAs for two COVID-19 vaccines, manufactured by Pfizer-BioNTech and Moderna. EUA is an authorization process used by the FDA if there is an emergency and enough evidence that the vaccine will be safe and helpful. Vaccines authorized for EUA still need to meet the FDA's rigorous standards for safety, effectiveness and quality.

How effective is the vaccine?
Both the Pfizer and Moderna vaccines were found to have a 94-95% efficacy to prevent COVID-19 symptomatic infection. Accumulating data show virtual complete protection against severe infection (hospitalization, need for a ventilator or death). Ongoing studies will tell us the durability of this protection. It is not known how well the vaccines protect against asymptomatic infection and transmission.

Will the vaccine give me the virus?
No. The vaccines contain a portion of mRNA, but not live virus. After the spike protein is produced, the mRNA is degraded. A normal immune response can lead to low grade fever or achiness, but this is not harmful. The full benefit of immunity won’t occur until a couple weeks after your second dose (booster dose). The risk of getting infected from someone who is infectious won’t diminish right away after vaccination.

Will the vaccine cause side effects?
As with other vaccines, it is normal to experience some pain, redness or swelling at the injection site, fatigue, headache, muscle aches, or low-grade fever following the vaccination, which should go away on their own in a day or two. This does not mean that the vaccine has given you COVID-19. These symptoms are typical reactions to most vaccines and are a sign that your immune system is doing exactly what it is supposed to do — building up protection to the disease.

Is the vaccine safe for pregnant or breastfeeding women?
Before the vaccine can be safely given to pregnant women, it had to be proven safe for the general population. So pregnant women are not included in phase 3 clinical trials. Data collection on pregnant women will be ongoing as this vaccine is offered. The CDC’s Advisory Committee on Immunization Practices (ACIP) endorses offering mRNA vaccine during pregnancy if there is a discussion with the healthcare provider. The mRNA vaccines are not considered live virus vaccines and are not thought to cause a risk to the infant. Contact your doctor for more information.

Could the COVID-19 vaccine cause an allergic reaction?
Allergic reactions to vaccines, in general, are rare. Some people have reported severe allergic reactions to the Pfizer-BioNTech vaccine, but these appear to be rare. People who have experienced severe reactions to prior vaccines or injectable drugs may still be able to get the Pfizer vaccine for COVID-19, but should discuss the risks with their doctor and be monitored for 30 minutes afterward. Talk to your doctor if you have a history of severe allergic reaction to a vaccine.

If I get the COVID-19 vaccine, will I test positive for the virus?
No. Positive tests for viral proteins (antigen tests) or nucleic acid (PCR tests) are due to COVID-19, not vaccine. A positive antibody test can be from infection or immunization.

Will the vaccine alter my DNA?
Receiving an mRNA vaccine will not alter your DNA. The mRNA from a COVID-19 vaccine never enter the nucleus of the cell, which is where our DNA (genetic material) is kept. This means the mRNA does not affect or interact with our DNA in any way. Once the mRNA triggers the immune response, it breaks down.

Do I still need the vaccine if I’m not high risk?
COVID-19 can be severe in any age group. In the Moderna trial, severe infections occurred in 15% of cases in the placebo group, but there were no severe cases in the vaccine group. The protection you get from the vaccine is not just for yourself but for others who are susceptible around you. Getting vaccinated is doing your part in getting to a goal of herd immunity. The more individuals who are immunized, the less effectively the virus can transmit.

Can’t I just let other people get the vaccine?
We know that vaccines save lives and can help us turn the page on the coronavirus. Vaccines have eradicated smallpox, nearly eliminated measles and polio, and minimized the impact of countless other diseases. To achieve a similar result from the COVID-19 vaccine requires a certain percentage of people get vaccinated in order to achieve herd immunity. We all need to work together to protect ourselves, our loved ones and our community, and the COVID-19 vaccine is the most effective way to keep all of us safe.

Will I be able to afford the vaccine?
Vaccine doses purchased with U.S. taxpayer dollars will be given to the American people at no cost. However, vaccination providers may be able to charge administration fees for giving the shot. Check with your health insurance company and location where you will be vaccinated about the cost, if any.

Do I need the vaccine if I already had COVID-19 and recovered?
Immunity does develop after COVID-19 infection. Re-infection is uncommon but is thought to develop as immunity wanes in the months following infection. Vaccine may be helpful to prevent re-infection if it has been more than 3 months since you tested positive.

Should I get the vaccine if I had a positive antibody test for COVID-19?
It is not recommended to use antibody testing to make decisions about immunizations. A positive antibody test is evidence, but not proof, of past infection. A positive antibody test is not a guarantee of immunity. In fact, there were cases of COVID-19 in the clinical trials in subjects who had positive antibodies.

How can I protect myself until I get the vaccine?
The best defense against COVID-19 is to continue following safety precautions. Cover your mouth and nose with a face mask when around others, avoid close contact with people who are sick, stay at least 6 feet away from people outside of your household, avoid crowds and wash your hands often and thoroughly.

At Edward-Elmhurst Health, we are following guidance from the CDC and local health departments regarding distribution of the COVID-19 vaccine. The vaccine is currently in limited supply so those at highest risk are getting vaccinated first, starting with frontline healthcare workers.

While we do not have scheduling or wait lists for patients at this time, we anticipate that high risk patients will be able to receive the vaccine as supplies increase in the coming months. It’s estimated that the general public should be able to start receiving the vaccine in the spring/summer of 2021.

This blog was reviewed by Jonathan Pinsky, MD, infectious disease physician and medical director of infection control and prevention at Edward Hospital. 

For the latest updates on the COVID-19 vaccine, please check EEHealth.org/coronavirus/vaccine.

Edward-Elmhurst Health offers screening options for COVID-19. Eleanor, your personal virtual assistant, can help you check your symptoms 24/7 and advise you on what to do next. We also offer Video Visits and E-Visits for COVID-19 symptoms.

The information in this article may change at any time due to the changing landscape of this pandemic. Read the latest on COVID-19.