Not only is it normal to have questions about the COVID-19 vaccine, it’s beneficial. You deserve to know about the safety and the effectiveness of the COVID-19 vaccines. We’ve compiled the most frequently asked questions to provide answers. Para español, haga clic aquí.

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Questions about who should receive a vaccine
Questions about safety and effectiveness
Questions about how the vaccine works
Questions about how the vaccine will impact the pandemic
Questions about clinical trials

Questions about who should receive a vaccine

Q: Who should not receive the COVID-19 vaccine?

A: There are no pre-existing conditions that are contraindications for the COVID-19 vaccine. If you have questions about a pre-existing condition or allergy, speak with your primary care provider. At this point in time, LVHN is not administering the vaccine to people younger than age 18.

If you have had a vaccine in the last 14 days, you should delay your COVID-19 vaccination. You should avoid receiving a vaccination while awaiting your second dose of COVID-19 vaccine and for 14 days after that dose.

Q: Will people who have gotten sick with COVID-19 still benefit from getting vaccinated?

A: Yes. While people who have tested positive for COVID-19 do produce antibodies, the antibody levels and how long they last are not known. Due to the severe health risks associated with COVID-19, and the fact that re-infection with COVID-19 is possible, you are advised to get a COVID-19 vaccine even if you have been sick with COVID-19 previously. At this time, experts do not know how long someone is protected from getting sick again after recovering from COVID-19. The immunity someone gains from having an infection, called natural immunity, varies from person to person, and the evidence suggests natural immunity may not last very long in some people.

Q: I have a health condition that prevents me from getting vaccines with live viruses. Does the COVID-19 vaccine use a live virus?

A: Both Pfizer/BioNTech’s and Moderna’s vaccines are mRNA vaccines. This means they are made from genetic material that provides your body with the code it needs to create spike proteins (not the virus) and build immunity. AstraZeneca’s and Johnson & Johnson’s are non-replicating virus-vectored vaccines. None of these vaccines are live vaccines. When vaccines are licensed, part of the information that will be provided will include who should or should not get each vaccine. At that time, we recommend talking with your health care provider to determine which vaccine will be the best one for you to get, given your medical history.

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Questions about safety and effectiveness

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Q: What are the side effects?

A: Pfizer has reported that some Phase III clinical trial participants experienced mild-to-moderate side effects with its investigational COVID-19 vaccine candidate. Scientists anticipate that the shots may cause mild flu-like side effects – including sore arm, muscle aches and fever. We recommend that you take ibuprofen or acetaminophen (if you can safely take them) before you get the vaccine. This will help to significantly alleviate the side effects.

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Questions about how the vaccine works

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Q: How does the vaccine for COVID-19 work?

A: Pfizer/BioNTech’s and Moderna’s vaccines use novel messenger-RNA, or mRNA, technology, which uses modified genetic material to cause the body to create a protein from the virus. The immune system then recognizes the protein as foreign and initiates an immune response. Pfizer/BioNTech’s vaccine is the first mRNA product to receive Emergency Use Authorization by the FDA. The study has enrolled 43,538 volunteers. About 42 percent of global participants and 30 percent of U.S. participants have racially and ethnically diverse backgrounds. In Pfizer/BioNTech’s late-stage clinical trial, 50 percent of the volunteers got the vaccine, while the other half got a placebo of saline (saltwater). Then they waited to see who would get sick. Only 170 volunteers out of 44,000 have so far gotten sick with COVID-19, and 95 percent of those were in the placebo group.

Q: Will the vaccine keep me from getting COVID-19?

A: Current data shows that both the Pfizer/BioNTech vaccine and Moderna vaccine are 95 percent effective in preventing a person from getting sick with COVID-19. During the clinical trials, scientists compared how many people in the vaccinated group and the placebo group went on to develop the disease.

The companies will continue to test people in the studies for antibodies to the COVID-19 virus, which would include people who did not show any symptoms of infection. This allows researchers to get a better sense of whether the vaccines protect against not only getting sick (experiencing symptoms), but also against infection (becoming infected without experiencing symptoms).

Q: Will COVID-19 vaccines cause me to test positive on COVID-19 viral tests?

A: No. These vaccines will not cause you to test positive on viral tests, which are used to see if you have a current infection. If your body develops an immune response, which is the goal of vaccination, there is a possibility you may test positive on some antibody tests. Antibody tests indicate you had a previous infection or vaccination and that you may have some level of protection against the virus. Experts are currently looking at how COVID-19 vaccination may affect antibody testing results.

Q: What is a vaccine?

A: According to the Centers for Disease Control and Prevention (CDC), a vaccine stimulates your immune system to produce antibodies and cellular immunity to combat a specific disease, like it would if you were actually exposed to the disease. After getting vaccinated, you develop immunity to that disease without having to get the disease first. This is why vaccines are necessary — they prevent disease by letting you develop immunity in a safe and controlled way.

Q: How many doses of a COVID-19 vaccine will I need?

A: The Pfizer/BioNTech vaccine requires a booster 21 days later, and the Moderna vaccine requires a second dose 28 days later. The different vaccine products are not interchangeable. The second dose must be completed with the same vaccine brand as the first dose. Both doses are important to ensure full protection.

Q: What if I miss my second dose?

A: These two COVID-19 vaccines are not completely effective unless you receive the second dose.

Q: Will getting the flu vaccine protect me from COVID-19?

A: A flu vaccine will not protect you from getting COVID-19, but it can help to prevent you from getting influenza (flu) at the same time as COVID-19. This can help keep you from having a more severe illness. While it’s not possible to say with certainty what will happen this winter, CDC believes it’s likely that flu viruses and the virus that causes COVID-19 will both spread during that time. You should encourage all of your friends and family to get flu shots.

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Questions about how the vaccine will impact the pandemic

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Q: Do I have to continue wearing a mask after I get the vaccine?

A: Yes, we should all continue wearing face masks, practicing excellent hand hygiene and social distancing until enough vaccine is manufactured and distributed, until we know how long a vaccine will protect us, and until our community shows reduced levels of spread.

It is unclear at this point if the vaccine prevents people from becoming infected with COVID-19 or if it prevents feeling sick when infected. That means you could still transmit virus after you’ve received your shot.

Q: Do the new vaccine trial results mean the end to the pandemic?

A: In the short term, no. The soonest that coronavirus vaccines could become widely available to the public would be in the spring. But if effective vaccines become available — and if most people get them — the pandemic could drastically shrink. This means we are one giant step closer to getting our lives back to normal provided as many people as possible get vaccinated as early as possible.

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Questions about clinical trials

Q: What does Emergency Use Authorization (EUA) mean?

A: In an emergency, like a pandemic, the FDA can make a judgment that it is worth releasing something for use even without following the typical timeline for a new vaccine or drug. The administrative portions of the trial have been sped up. The scientific analysis of clinical trial participants remains the same for these and all other vaccines. If there’s evidence that strongly suggests that patients have benefited from the vaccine in clinical trials and that it is safe, the agency can issue an EUA to make it available. The FDA has issued EUAs many times previously in other situations. The EUA process is well established and is not newly created to address COVID-19 vaccine development.

Current data from the manufacturers for the Pfizer/BioNTech vaccine, and the upcoming one from Moderna, strongly indicate that both vaccines are safe and effective. The FDA granted EUA for the Pfizer/BioNTech vaccine on Dec. 11 and will review Moderna’s vaccine on Dec. 17. Even after receiving EUA, vaccines will continue to be studied, as is true with all vaccines.

Q: Are there non-mRNA vaccines being studied?

A: The AstraZeneca/Oxford team, as well as Johnson & Johnson/Janssen, are also working on vaccines that use different technology for delivering the viral genes that can produce viral proteins to activate the immune system. Novavax and Sanofi/GlaxoSmithKline are working on a vaccine that uses proteins themselves to trigger an immune response. All are close to completing their testing.

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