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The clinical trials for COVID-19 vaccines have involved tens of thousands of volunteers of different ages, races, and ethnicities. Clinical trials for vaccines compare outcomes (such as how many people get sick) between people who are vaccinated and people who are not. Because COVID-19 continues to be widespread, the vaccine clinical trials have been conducted more quickly than if the disease were less common. Results from these trials have shown that COVID-19 vaccines are effective. They have also shown no serious safety concerns after more than 8 weeks following vaccination. This is an important milestone, as it is unusual for adverse effects caused by vaccines to appear after this amount of time.
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Yes, all three authorized or approved COVID-19 vaccines are safe and effective at protecting against COVID-19. To learn more about the safety of the vaccines and how they’ve been tested and monitored, visit the CDC website here.
To learn about the types of authorized or approved COVID-19 vaccines, their safety, ingredients, and more please visit the CDC website here.
The Pfizer and Moderna vaccines use messenger RNA or mRNA, to trigger the immune system to produce protective antibodies and memory cells against the coronavirus. These are the first vaccines to use mRNA. It is important to note that neither of these vaccines uses the coronavirus itself, and neither can cause COVID-19.
The Johnson & Johnson vaccine is a vector vaccine. That means it contains a weakened version of a virus that causes the common cold that is different from the coronavirus. The cold virus is modified to carry information about the coronavirus to the body. This vaccine causes the body to make a protein that is unique to the coronavirus. This prompts the immune system to produce protective antibodies against the coronavirus. Like the Pfizer and Moderna vaccines, this vaccine does not use the coronavirus itself, and cannot cause COVID-19.
None of the vaccines affect a person’s DNA. They also do not cause coronavirus.
All the approved vaccines are safe and highly effective. The best vaccine is the vaccine you can get as soon as possible. However, only the Pfizer vaccine has been approved for use in individuals aged 5-11. Vaccine clinics now publish which vaccine they are offering, so make sure to schedule at a clinic offering the Pfizer vaccine if you are scheduling for someone under 18.
Individuals 5-17 years old are considered fully vaccinated once two weeks have passed after receiving the second dose of the Pfizer vaccine.
Individuals aged 18 and older are considered fully vaccinated if they have completed a primary COVID vaccination series within 5 months (Pfizer or Moderna) or within two months (J&J) OR they have received all recommended vaccine doses including boosters and additional shots for some immunocompromised people.
No. Vaccines currently in clinical trials in the United States won’t 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 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.
Yes. On November 19, 2021, the Michigan Department of Health and Human Services issued a Public Health Advisory for all Michiganders, regardless of vaccination status, to wear a mask in indoor public settings. You can view the Public Health Advisory here.
You can find our updated Quarantine and Isolation guidelines here.
Yes. Getting sick with COVID-19 offers some protection from future illness with COVID-19, sometimes called “natural immunity.” The level of protection people get from having COVID-19 may vary depending on how mild or severe their illness was, the time since their infection, and their age. No currently available test can reliably determine if a person is protected from infection.
All COVID-19 vaccines currently available in the United States are effective at preventing COVID-19. Getting a COVID-19 vaccine gives most people a high level of protection against COVID-19 even in people who have already been sick with COVID-19.
Emerging evidence shows that getting a COVID-19 vaccine after you recover from COVID-19 infection provides added protection to your immune system. One study showed that, for people who already had COVID-19, those who do not get vaccinated after their recovery are more than 2 times as likely to get COVID-19 again than those who get fully vaccinated after their recovery.
The CDC has recommended that pregnant women and women planning to become pregnant may be offered the vaccine, in consultation with their health care provider.
Some people experience temporary swelling of lymph nodes under their arm after getting the Pfizer or Moderna vaccines. This is part of the immune system’s expected response to receiving the vaccine. Sometimes this has been mistaken for a sign of possible spread of breast cancer to the lymph nodes; therefore, delaying the mammogram can reduce the chance of being confused by this finding. If you are concerned about delaying one, contact your healthcare provider.
The vaccines not only protect people who get the vaccine but will protect people who have not been vaccinated by reducing the rate of person-to-person transmission and increasing community protection. By reducing the spread of the virus, they also reduce the chance that additional COVID-19 variants will develop. Vaccination has led to community protection from other illnesses, including whooping cough (pertussis).
After COVID-19 vaccination, you may have some side effects. This is a normal sign that your body is building protection. The side effects from COVID-19 vaccination may feel like flu and might even affect your ability to do daily activities, but they should go away in a few days. Your arm may be sore, red, or warm to the touch. You may experience a low-grade fever, headache, and just a general feeling of “not yourself”. These are signs that your immune system is doing exactly what it is supposed to, which is produce an immune response for you to have protection against this disease.
When you get your vaccine, you will get a link to get the “V-safe After Vaccination Health Checker” application for your phone. Through V-safe, you can quickly tell the CDC if you have any side effects after getting the COVID-19 vaccine. CDC may follow up by phone to get more information. V-safe will also remind you to get the second COVID-19 vaccine dose when needed.
The COVID-19 vaccine is free in the United States. Vaccine providers will be able to charge a fee to administer the shot, but this fee should be covered by public or private insurance, or by a government relief fund for the uninsured.
The Pfizer COVID-19 vaccine is fully FDA approved for individuals ages 18 and older and is available under emergency use authorization for individuals 5 years of age and older as well as a single booster dose for individuals 12 years of age and older at least five months after completing a primary series of the vaccine. Learn more here.
The Moderna COVID-19 vaccine is available under emergency use authorization for individuals ages 18 and older as well as a single booster dose for individuals 18 years of age and older at least five months after completing a primary series of the vaccine. Learn more here.
The Jassen (Johnson&Johnson) COVID-19 vaccine is available under emergency use authorization as a single primary vaccination dose for individuals 18 years of age and older and as a single booster dose for individuals 18 years of age and older at least two months after completing primary vaccination with the vaccine. Learn more here.