COVID-19 Vaccines - Answers to Common Questions

Trusted Websites for Accurate Answers to COVID-19 Questions

There are current and future questions not addressed in this brief handout.
In addition, some answers may change based on new studies and new data.
When seeking answers to your questions, only use science-based websites. Here are some of the best:
Centers for Disease Control and Prevention (CDC) website: https://www.cdc.gov/coronavirus/2019-ncov/vaccines.
American Academy of Pediatrics website for parents: www.healthychildren.org
Children's Hospital of Philadelphia (CHOP) Vaccine Education Center website: https://www.chop.edu/centers-programs/vaccine-education-center
Always follow the most current CDC recommendations if they are different than those in this document.

Efficacy of the COVID-19 Vaccine:

Vaccine Efficacy. All the vaccines approved by the FDA for use in the US are highly effective. Most vaccines provide over 90% protection against getting sick with COVID-19. The vaccines are even better at preventing serious symptoms, complications and the need for hospital or ICU admission. They are much more effective than flu vaccines.
Other Major Benefits. Vaccines also prevent the rare serious delayed onset complications from COVID-19 infections that can occur in some people. One example is multisystem inflammatory syndrome in children (also called MIS-C). Another is "long hauler" symptoms (such as brain fog or chronic breathing problems). Key: Vaccines prevent death and long-term complications from COVID-19 infections.

Safety of the COVID-19 Vaccine:

Vaccine Safety. Very safe based on tracking thousands of vaccinated people. Most people get a sore arm for a few days. About half get some general symptoms for about 24 hours, such as feeling tired and achy. A smaller number have a fever. These are the normal side effects seen with most vaccines and they go away quickly. They show your immune system is working. Serious reactions are extremely rare.
Blood Clot Concerns. Very rare. Occur in about 1 person per million vaccinated people. Blood clots occur much more commonly in people who get the natural COVID-19 infection. (Note: have NOT occurred with Moderna or Pfizer vaccines)
Best COVID Vaccine. Any vaccine approved by the FDA is highly effective and safe. Get the first one that becomes available to you. It will protect you and your family.
Vaccine Site. Find a nearby vaccine site at vaccines.gov or call your doctor's office.

Protection after the COVID-19 Vaccine:

Start of Vaccine Protection. Full protection is reached about 2 weeks after you complete the vaccine series.
Duration of Vaccine Protection. Research data has confirmed that protection is still high at 6 months after completing the vaccine series (April 2021). Experts predict the protection may last for 12 months or longer, but we need to wait for more data.
Booster Shots. Experts predict we may need them yearly, just like flu vaccine boosters. Ongoing studies will tell.

Reinfection after the COVID-19 Vaccine:

COVID-19 Variants and Vaccine Protection. For now, the current vaccines protect against the current variants in the US. The vaccinated person usually does not get infected. If they do, they develop either a mild illness or an asymptomatic infection. They are protected against serious symptoms and any complications. By contrast, natural immunity does not protect against some of the variants.
Re-infections. Reinfections can occur after natural infections. Vaccination provides much better protection against future infections.
Quarantine after Exposure. If you are vaccinated and 2 weeks have passed since your final dose, you do not have to quarantine for 10 days after close contact with a COVID-19 infected person.

Special Patients and the COVID-19 Vaccine:

Children and Teens. Safe and highly effective vaccines are available. Some vaccines are 2 doses, given 3-4 weeks apart. Others are single dose. Similar to flu shots, they will probably provide protection for 6 to 9 months. At this time, vaccines have been tested and are FDA approved for 12 years and older. Trials on children younger than 12 years have started (May 2021). Importance: while most children have mild or asymptomatic infections, they can get rare complications such as MIS-C. Also, they can innocently transmit the disease to others.
Pregnant Women. Vaccines are approved and safe.
Breastfeeding Mothers. Vaccines are approved and safe. Studies show that breastmilk passes antibody protection against COVID-19 to the baby.
Underlying High Risk Conditions. Vaccines are approved and safe. These patients need the vaccine protection the most. If you have questions about a specific condition, discuss with your doctor.
Person Already had the Disease. Get the vaccine. It provides higher levels of antibodies and better protection than the natural disease. Restriction: not approved until you are over any acute symptoms and the 10 days of isolation have passed.

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