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Vaccine Frequently Asked Questions

Full Pfizer FDA Approval

What does full approval of the vaccine mean?

Full approval by the U.S. Food & Drug Administration grants a license to vaccine manufacturers. This means they can market their product in the United States for use in the population for which it is approved.

Until now, COVID-19 vaccines were distributed in the United States under emergency use authorization (EUA). These were issued after clinical trials tracked results for tens of thousands of volunteers for at least two months. EUA is a way to speed delivery of safe and effective medicines during public health emergencies, such as the COVID-19 pandemic.

Full approval, such as that issued for ages 16 and older for the vaccine by Pfizer-BioNTech, takes a longer review. The original tens of thousands of clinical trial participants are monitored for at least six months. In addition, regulators review any reports of adverse reactions among the hundreds of millions of doses given in the United States. Vaccine manufacturers also must submit much more detailed documentation.

Read a step-by-step explanation of the vaccine development process.

Does approval mean one vaccine is better than another?

It is all a matter of timing. The Pfizer-BioNTech vaccine was the first to earn emergency use authorization. That means the company got an earlier start on the long process of documentation and application.

Moderna has applied for full approval of its two-shot vaccine, with results expected this fall. Janssen (a division of Johnson & Johnson) has said it will seek full approval of its single-dose vaccine.

What does full approval mean for the booster shots?

When a vaccine is licensed, it makes it easier for physicians to prescribe an immunization, including booster shots when appropriate.

Currently, people with weakened immune systems who received the Pfizer or Moderna vaccine can receive a third dose.

Additionally, the Pfizer booster is authorized with at least six months passing since receiving the second dose for the following groups:

  • Anyone 65 or older
  • Those in a long-term care facility
  • Anyone 18-64 with underlying medical conditions
  • Anyone 18-64 whose occupation puts them at risk of exposure

Booster Shot

What is happening with the booster?

The U.S. Food and Drug Administration already has authorized booster shots for people with weakened immune systems.

At this time, the only authorized booster is for the vaccine by Pfizer-BioNTech. Boosters are available only to patients who received two doses of the Pfizer vaccine, with at least six months passing since receiving the second dose.

The following groups are recommended to receive a booster:

  • People with compromised immune systems
  • Anyone 65 pr older
  • Those in a long-term care facility
  • Anyone 50-64 with underlying medical conditions

The following groups may receive a booster:

  • Anyone age 18-49 with underlying medical conditions
  • Anyone age 18-64 whose occupation puts them at risk of exposure

The need for a second dose for the single-shot vaccine by Janssen (a division of Johnson & Johnson) remains under review.

We were told the vaccines were highly effective. Why do we need a booster?

The authorized vaccines continue to provide very strong protection, particularly against severe illness, hospitalization and death.

However, health officials cite two reasons for the need for a booster: Evidence shows vaccine-induced protection against COVID-19 infection begins to decrease over time, which also occurs with a natural infection. And the vaccine effectiveness is generally not as strong against the Delta variant. Boosting the previous vaccine series should provide more protection against the Delta variant and probably other variants, too.

In fact, many vaccines require multiple doses – the polio vaccine and the diphtheria-tetanus vaccine are just a couple of common examples.

I’m not vaccinated. Is it too late to bother getting my first shot?

It’s not too late! Vaccination is recommended for everyone, with rare exceptions for allergies, 12 years and older.

Although UM Health-West already distributed nearly 50,000 doses of COVID-19 vaccines by mid-August, we have supplies to continue immunizations.

The vaccines authorized for use in the United States (the vaccine by Pfizer-BioNTech now is fully licensed for ages 16 and older) are highly effective, even against the Delta variant, particularly in preventing severe illness, hospitalization and death.

Why does it seem as if guidelines change so often?

This disease was essentially unknown before 2020, and the vaccines have been in wide use in the United States for even less time. Every day brings more studies on what is safe and what is not.

This emphasizes why it is important to apply as many precautions as possible to prevent COVID-19 and to keep reducing the risk to the community.

By combining individual precautions (wearing a mask in public, keeping our distance) with shared precautions (testing and vaccination efforts) we can be confident that we will bring the pandemic to an end.


The Delta Variant and Others

What is a coronavirus variant, and why should I be concerned?

Variants are common with every virus – think of the season flu as an example. Every time a virus reproduces, there is a chance for a genetic copying “error” or mutation.

Mutation and evolution often result in a virus that spreads more easily, which is what appears to have happened with the highly contagious Delta variant. Studies also suggest that this variant, which has become dominant in many parts of the country, including Michigan, causes more severe illness.

This is why it is so important to reduce infections through vaccination and other precautions. Every time the virus is passed on is another opportunity to mutate.

I’m fully vaccinated. Do I need to worry about the Delta variant?

The primary concern is for unvaccinated people. However, no vaccine is 100% effective.

The COVID-19 vaccines authorized for use in the United States (the vaccine by Pfizer-BioNTech now is fully licensed for ages 16 and older) continue to show strong protection in preventing severe disease, hospitalization and death. This includes illness caused by the Delta variant.

However, the Delta variant is not only more contagious, but may cause more severe illness than earlier strains.

Studies also show that it is possible for fully vaccinated people to experience rare “breakthrough” infections and spread the virus to others.

For these reasons, the CDC is recommending layered prevention strategies, such as wearing masks in public settings.

Choosing A Vaccine

Which vaccine should I get?

The widely accepted medical recommendation is that the best vaccine to receive is the vaccine that is first available for you.

Each of the three currently authorized vaccines (the vaccine by Pfizer-BioNTech now is fully licensed for ages 16 and older) offers outstanding protection against COVID-19. Each has been scientifically tested with constant monitoring for safety with diverse populations.

Shouldn’t I take my chances with COVID, rather than a blood clot?

The risk of COVID-19 is far more significant than the very small risk of adverse effects from any of the vaccines.

With nearly 360 million doses of COVID-19 vaccines administered in the United States between December 2020 and mid-August 2021, serious adverse effects were reported in an tiny fraction of a percent of those who received the vaccine.  For example, anaphylaxis, a severe allergic reaction, has occurred in about 2 to 5 people per million vaccinated.

By comparison, thousands of unvaccinated Americans are hospitalized every single day with COVID-19.


About COVID-19 Vaccines

Is one vaccine more effective than the other?

It is impossible to compare efficacy rates of the vaccines, and it is important to remember that they all offer outstanding protection. Each has been scientifically proven to be safe and effective in preventing severe cases and hospitalization.

What is the difference between the vaccines?

While each takes a slightly different approach, all are safe and effective.

The first two vaccines to be authorized for use, by Pfizer-BioNTech and Moderna, (the vaccine by Pfizer-BioNTech now is fully licensed for ages 16 and older) use mRNA technology to teach the body’s immune system to build defenses against the coronavirus. These vaccines start iwth a regiment of two shots delivered several weeks apart. The vaccines also have special ultra-cold storage requirements.

The vaccine by Janssen (a division of Johnson and Johnson) uses a harmless adenovirus (such as the virus we refer to as the “common cold”) to deliver genetic instructions to teach the body to protect against the coronavirus. This is a single-shot vaccine with conventional storage requirements, making it easier to distribute.

Will taking the vaccine give me COVID-19?

None of the vaccines authorized for use can give you COVID-19. They do not contain the coronavirus that causes COVID-19.

How much will the vaccine cost?

The vaccine itself is funded with federal tax dollars. A small fee is charged to administer the shot, but this fee should be covered by public or private insurance, or by a government relief fund for the uninsured. Cost will not be a barrier to vaccination.

I heard that these vaccines use some new technology. Isn’t that dangerous?

The Moderna and Pfizer-BioNTech vaccines were developed using “messenger RNA,” or mRNA, to teach the body to fight off the coronavirus. Although this is a breakthrough for vaccine development, the technology has been around for decades, and it has been clinically tested in the treatment of a wide range of infections. Doctors and researchers believe mRNA has the potential to fight other diseases, like cancer.

The third vaccine authorized, by Janssen (a division of Johnson & Johnson), uses a safe and proven approach that has been studied since the 1970s. It uses a harmless virus to deliver instructions to teach the body to protect against the coronavirus.

Won’t these mRNA vaccines change my DNA?

No, because, as the federal Centers for Disease Control notes, mRNA never enters the nucleus of the cell, which is where our DNA is kept. And in the case of the Janssen/Johnson & Johnson vaccine, this type of “viral vector vaccine” does not interact with DNA in any way.

Find out more about how mRNA vaccines work.

Find out more about how viral vector vaccines work.


Vaccine Eligibility & Distribution

When can I get the vaccine?

You can view the current phase of distribution and scheduling details at UM Health-West here. For a full list of the phases and who is included, visit Vaccinate West Michigan.

Who should get the vaccine?

The vaccines are recommended, with very few exceptions, for all people 12 and older, including women who are pregnant, breastfeeding, or trying to get pregnant.  They have been found to be safe and effective regardless of age, race, gender or weight.

All vaccines are being reviewed in expanded clinical trials to include younger patients.

You should not get the vaccine if you had a severe allergic reaction after a previous dose, or if you are severely allergic to any ingredient of the vaccine. See the ingredients for the Pfizer vaccine, the Moderna vaccine and the Janssen/Johnson & Johnson vaccine. General information about vaccines and allergies can be reviewed here.

Where will the vaccine be administered?

University of Michigan Health-West is offering the COVID-19 vaccine at several locations around West Michigan.

Schedule your vaccine appointment here or by calling 616.252.6161.

How is it administered?

The COVID-19 vaccine is delivered with an injection in the arm. Similar to a flu shot, the process takes just a few minutes. Depending on which vaccine you receive, you may need a booster shot several weeks later. You will receive information about scheduling the second dose, if necessary, when you schedule your vaccination.

Will I know which vaccine I am receiving?

Yes, every patient will be informed which vaccine they are receiving.


Safety, Side Effects & Other Concerns

What are the side effects?

The most commonly reported side effects, which typically lasted several days, are pain at the injection site, tiredness, headache, muscle pain, chills, joint pain, and fever.  These symptoms, which may be more likely and noticeable after the second dose, are typically mild and temporary. They are indications that the vaccine is working.

Serious side effects are extremely rare. They include a type of blood clot called thrombotic thrombocytopenia, and an allergic reaction called anaphylaxis.

These vaccines are the most closely monitored for safety in U.S. history. Find out more.

Is it true that younger patients have more serious side effects?

Clinical trials found that the younger age group was slightly more likely to experience fever, aches and pains. This is possibly due to the robust immune system in younger patients.

Warnings about rare allergic reactions, including anaphylaxis, are the same as for adults. Although the risk is extremely rare, the FDA says the vaccine should not be given to anyone with a history of a severe allergic reaction to any ingredients of the vaccine.

What is the risk of an allergic reaction?

The CDC, which is closely tracking the rate of allergic reactions to vaccines, reports that they are rare. Anaphylaxis, for example, has been reported in about 2 to 5 people million per vaccinated.

Although the vaccines do not contain eggs, latex or preservatives, those who have allergies to eggs or other substances should remain after vaccination for 30 minutes for observation.

You should not get the vaccine if you had a severe allergic reaction after a previous dose, or if you are severely allergic to any ingredient of the vaccine. See the ingredients for the Pfizer vaccine, the Moderna vaccine and the Janssen/Johnson & Johnson vaccine.

General information about vaccines and allergies can be reviewed here.

Can I get the vaccine if I’ve had COVID-19 or think I may have had COVID-19 in the past?

Yes, you should get vaccinated if you’ve had COVID-19 previously. There is not enough information currently available to say if or for how long after infection someone is protected from getting COVID-19 again; this is called natural immunity. Early evidence suggests natural immunity from COVID-19 may not last very long, but more studies are needed to better understand this.

The CDC advises that previously infected people should delay vaccination until they are fully recovered. Talk with your doctor if you have questions about receiving the vaccine.

Should I get the COVID-19 vaccine at the same time as another vaccine?

You can get the COVID vaccines and other vaccines at the same visit The CDC no longer recommends a timing gap.

Can the vaccines cause infertility or miscarriage?

No cases of infertility or miscarriage have been linked to the vaccines. A disinformation campaign has been circulating online, claiming that antibodies interfere with placental proteins and prevent pregnancy. This is not plausible, because no viral infections (which trigger antibody production) have been linked to infertility. The CDC has stated that pregnant or lactating patients can receive the vaccine if they are eligible, following a discussion about the relative risks.

Do the authorized vaccines contain fetal tissue?

The Janssen (a division of Johnson & Johnson) vaccine has drawn attention because the manufacturing process used cells derived from fetal tissue. These cloned cells were used to grow the harmless adenovirus that the vaccine uses to deliver genetic instructions to teach the body to protect against the coronavirus. The vaccine itself contains none of the cells.

The other two vaccines currently authorized, by Pfizer and Moderna, were tested on fetal cell lines. However, cells were not used in development or production of those vaccines.

In all cases, these cells are clones or “immortalized” copies of decades-old fetal cells. Immortalized cell lines are established by culturing fetal cells in such a way that they continue growing and multiplying indefinitely. While immortalized cell lines began with fetal cells, they no longer contain fetal body parts, and no fetal tissue remains. No cells remain from the original fetal tissue.


After Vaccination

I lost my vaccine card, what do I do?

The Michigan Department of Health and Human Services launched a new website, the Michigan Immunization Portal, that allows any individual 18 and older who has been immunized in the state of Michigan to check and obtain a copy of their vaccination record online.

Do vaccinated people still need to observe restrictions, like avoiding crowds, wearing a mask, etc.?

The federal Centers for Disease Control guidelines state that people can resume their regular activities after their final dose. However, to reduce the risk of being infected with the Delta variant and possibly spreading it to others, the CDC recommends wearing a mask indoors in public in areas of substantial or high transmission.

You can look up the risk level for your county here.

Additionally, masks may still be universally required in certain settings, such as buses, planes, prisons and homeless shelters. Hospitals and healthcare settings, including UM Health-West, will continue to require mask-wearing.

The CDC guidance defers to local and state requirements including those established by local businesses.

Can I still be a carrier if I’m vaccinated?

The risk of you developing COVID-19 remains very low if you are fully vaccinated. However, it is still possible that you could spread the virus to others. Vaccination does not completely protect you from being infected. It primarily makes your body better at fighting off the infection. That might take some time, meaning you could be carrying the virus as your immune system goes to work.

As we continue to learn more about how the virus is transmitted, it’s important to keep in mind the transmission risk for vulnerable groups. The CDC continually updates its guidance on safe activities here.

Will scientists continue tracking the safety and effectiveness of the vaccine?

Federal oversight does not end once the vaccines are approved. Local healthcare workers, who were among the first to get the vaccine, are using an after-vaccine health checker to provide additional data to a national database. Anyone who gets the vaccine may also use the vaccine reporting system – VAERS – to report side effects.

The CDC also recently released its V-safe smartphone tool, which allows users to tell the CDC about any side effects after getting the COVID-19 vaccine.

For additional information, visit Michigan Medicine’s COVID-19 Vaccine FAQs.