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COVID-19 Vaccine Information: Distribution and Answers to Other Common Questions

Receiving the Vaccine

How does the vaccine work?

The Pfizer and Moderna vaccines consist of genetic material called mRNA encased in tiny particles that transport it into our cells. From there, our cells use this mRNA to make a protein which then stimulates the immune system to make antibodies that protect against the virus. These vaccines do not have any impact on our genes. The vaccine material breaks down in the body shortly after it is taken into our cells.

Once fully vaccinated, how quickly would a person test positive for antibodies?

Within two weeks. Because the vaccine is very effective, antibody testing after receiving the vaccine is not recommended.

What if I am sick with COVID-19 or another acute respiratory illness?

You should wait until you are better and then get your vaccine.

If I've already had COVID, do I need the vaccine?

Yes, you should still get vaccinated because you are still at risk for a repeat infection, even if you already got COVID. The vaccine will help protect against severe infection and hospitalization.

How soon can I get a COVID-19 vaccine after a COVID-19 infection?

Following a COVID-19 infection, you should wait to get a COVID-19 vaccination or booster until you no longer have symptoms and you have completed, at minimum, a 10-day isolation period.

You should wait longer than 10 days if you have any of the following conditions:

  1. You were severely ill from COVID-19 (i.e., required hospitalization, intensive care, or ventilation support), in which case you should wait until you no longer have symptoms of COVID-19 and have completed at least a 20-day isolation period;
  2. You are severely immunocompromised, in which case you should wait until you no longer have symptoms of COVID-19 and have completed at least a 20-day isolation period;
  3. You received monoclonal antibody therapy for COVID-19, in which case you should wait until you no longer have symptoms of COVID-19 and at least 90 days have passed since you received monoclonal antibody therapy.

For additional guidance, please speak with your clinician before getting vaccinated.

Vaccine Distribution

What is the immunization schedule for the vaccine?

What if I am on quarantine when I am offered the vaccination?

To protect others, you must wait until after your quarantine period ends to get vaccinated.

How long should an individual wait to receive the COVID-19 vaccine after receiving another vaccine?

COVID-19 and other vaccines may now be administered without regard to timing of other vaccines. This includes simultaneous administration of COVID-19 and other vaccines on the same day.

Potential Vaccine Side Effects

What are the side effects of the vaccine and how frequent are they?

Side effects for the vaccines are usually mild, and at worst are moderate and typically resolve in 1-2 days post-vaccination. Common side effects can include pain at the injection site, muscle aches, headache, nausea, fatigue and sometimes fever. These side effects are a sign the vaccine is working, and your body is mounting the immune response it needs to protect you from severe COVID-19 infection. These side effects are much less severe than actual COVID-19 infection and are not life-threatening.

If an individual has had a vasovagal reaction (i.e., fainting) after their first dose of the vaccine, should they receive a second dose?

Yes. Vasovagal reactions, such as fainting or a feeling like you are going to pass out, can happen in different situations including receiving a vaccine, getting your blood drawn, etc., and are considered benign (i.e., there are no long-term consequences). An individual can and should receive their second dose to be fully protected, but they should indicate this to the vaccinator so that they can be vaccinated in a recliner or recumbent position.

If I experience a side effect from the vaccine should I skip the booster dose?

No, don't skip the booster dose. You may wish to consider taking Tylenol and/or Benadryl when getting your next dose. You might also want to plan for your booster dose 2-3 days before you are schedule to work in case you need to stay at home. If you take Benadryl, you should not drive as it causes drowsiness. 

Should I take medication prior to my COVID vaccination in order to avoid experiencing side effects?

Routine use of prophylactic (preventive) pain medicines before you get your vaccination is not recommended. However, if you experience side effects after receiving your vaccination (such as swelling or pain at the vaccination site, fever, headaches, or body aches) then taking an over-the-counter pain medicine (such as Tylenol or ibuprofen) may be helpful in managing those symptoms.

How can I tell if side effects are from the vaccine or from actual COVID-19 infection?

Symptoms that are side effects of the vaccine typically go away on their own within a couple of days and are a sign that the immune system is working. If side effects continue for more than 72 hours, they should be reviewed by a clinician. For severe side effects, contact your doctor or Urgent Care.

The vaccine does not cause respiratory symptoms or a loss of taste or smell, which are sometimes seen with a true COVID-19 infection. For these symptoms and/or if you have had a known or suspected COVID-19 exposure within the past 10 days, you should call your doctor.

I have read that the COVID vaccine can cause swollen lymph nodes in the underarm on the side of the injection that can be detected on a mammogram. Should I delay scheduling my routine screening mammogram?

Swollen lymph nodes in the underarm on the same side as the injection site may occur after COVID vaccination and may persist for up to several weeks. While swollen lymph nodes due to the vaccine are not worrisome, they may be detected on a routine screening mammogram and might need additional testing. If possible, try to schedule both doses of your COVID vaccine series before an upcoming mammogram. If that is not possible and if it will not result in undue delays, try to schedule your routine screening mammogram approximately 4-6 weeks after your second dose of a COVID-19 vaccine.

Vaccination for High Risk Communities

Can kids get the vaccine?

Yes. We encourage eligible children to get vaccinated against COVID-19 to help protect against severe infection and hospitalization. Read answers to some commonly asked questions about the vaccine and kids here.

Is the vaccine safe for people with comorbidities?

Yes. Patients with comorbidities have the presence of more than one medical condition. We know that people with underlying health conditions are at a higher risk for getting more severe cases of COVID-19. That’s why it’s important that those individuals get vaccinated as soon as they are eligible to do so.

Some of the conditions that put people at a higher risk of severe COVID-19 include cancer, obesity, heart conditions such as coronary artery disease, chronic kidney disease and chronic obstructive pulmonary disease. Those with liver disease, cystic fibrosis, asthma, and anyone with an immunocompromised state might be at an increased risk for severe illness as well.

Should individuals who had a prior anaphylactic reaction to another vaccine receive the COVID-19 vaccine?

If you previously have had an anaphylactic reaction to another vaccine or medication, you still may receive the COVID-19 vaccine, but we will ask you to notify the staff and be monitored in the vaccination clinic for 30 minutes after you receive your injection.

The ingredients of each vaccine are listed in the FDA facts sheets which can be accessed here.

If I am taking medications, are there any contraindications to receiving the vaccine?

No, but if you are receiving immunosuppressant medication (such as steroids, certain drugs to treat inflammatory conditions, current cancer therapy, etc.), you should talk with your prescribing clinician as the medication might interfere with your body’s ability to develop a full immune response to the vaccine. They may be able to help to recommend a time for you to get vaccinated.

Is it safe to receive the vaccine if I have a known allergy to a medication, a different vaccine or to some sort of food?

Unless you have had an allergic reaction to a previous dose of the type of COVID-19 vaccine you are planning to get or are allergic to one of the ingredients in the vaccine (e.g., polyethylene glycol or polysorbate), you can get the vaccination. If you have concerns regarding your history of allergic reactions, you should discuss this with your regular clinician before getting vaccinated.

Should individuals who carry an Epi-Pen® receive the COVID-19 vaccine?

The rate of allergic reactions in the clinical data was very, very low.

However, we recommend individuals discuss the risks and benefits of vaccination with the allergist/immunologist before scheduling their vaccination. You should notify the staff at our vaccination site of any prior allergic reaction before receiving the COVID-19 vaccine.

All vaccination sites will be prepared to respond to any allergic reactions in the unlikely case that they occur.

Additional Vaccine Information

How can I learn more?

Talk with your healthcare provider, call your local or state health department or contact the Centers for Disease Control and Prevention at 1-800-232-4636 (1-800-CDC-INFO) or visit CDC’s vaccine website:

YNHHS will be updating and distributing more generally asked questions and answers as more information becomes available.