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Administering Vaccines
Billing and Reimbursement
Combination Vaccines
Contraindications and Precautions
COVID-19 and Routine Vac
Documenting Vaccination
Hepatitis A
Hepatitis B
Meningococcal ACWY
Meningococcal B
Scheduling Vaccines
Storage and Handling
Travel Vaccines
Vaccine Recommendations
Vaccine Safety
Varicella (chickenpox)
Zoster (shingles)
Disease Issues Administering Vaccines
Vaccine Recommendations Scheduling Vaccines
Vaccine Products Contraindications and Precautions
COVID-19 Vaccines for Adolescents and Adults Vaccine Safety
COVID-19 Vaccines and Pregnancy Storage and Handling
Guidance from CDC about COVID-19 vaccines is evolving rapidly. To ensure access to the most current guidance, Ask the Experts answers often connect our readers directly to vaccine resources provided by the Centers for Disease Control and Prevention (CDC).

For a comprehensive collection of COVID-19 tools and resources, visit IAC's Vaccines: COVID-19 main page: www.immunize.org/covid-19. For alerts about new IAC or CDC COVID-19 resources, subscribe to our weekly newsletter, IAC Express.
Disease Issues
What is COVID-19?
COVID-19 is the name given to the disease caused by infection with the SARS-CoV-2 coronavirus. This new virus was first detected as a cause of human illness in late 2019 in Wuhan, China, and triggered a global pandemic in 2020. The virus is thought to spread mainly from person to person, mainly through respiratory droplets produced when an infected person coughs, sneezes, or talks. These droplets can land in the mouths or noses of people who are nearby or possibly be inhaled into the lungs.
The incubation period after exposure ranges from 2–14 days, with an average of about 5 days. People with COVID-19 are generally considered infectious up to 48 hours before symptom onset through 10 days after onset, though people with severe illness may be infectious longer. Severity ranges from asymptomatic infection to severe illness. Symptoms may include fever or chills, cough, shortness of breath or difficulty breathing, fatigue, muscle or body aches, headache, new loss of taste or smell, sore throat, congestion or runny nose, nausea or vomiting, and diarrhea.
Where can I find answers to more clinical questions about COVID-19 disease, diagnosis, treatment and care of patients?
The CDC has assembled clinical questions and answers at this site: www.cdc.gov/coronavirus/2019-ncov/hcp/faq.html.
Vaccine Recommendations Back to top
Where can I find current COVID-19 vaccine recommendations?
The CDC's Advisory Committee on Immunization Practices (ACIP) has published recommendations for mRNA COVID-19 vaccines that have received Emergency Use Authorization (EUA) from the federal Food and Drug Administration (FDA). Until vaccine supplies are sufficient, the ACIP also has issued recommendations for prioritizing recipients based upon either risk of serious outcomes or risk of occupational exposure. State and local public health officials are responsible for COVID-19 vaccination program implementation: consult them for details about vaccination policies in their jurisdiction. All ACIP COVID-19 vaccine recommendations can be accessed here: www.cdc.gov/vaccines/hcp/acip-recs/vacc-specific/covid-19.html.
In addition to ACIP recommendations for the use of these vaccines, CDC has published important interim clinical considerations for vaccination of eligible recipients: www.cdc.gov/vaccines/covid-19/info-by-product/clinical-considerations.html.
Has CDC developed a frequently asked question (FAQ) page for COVID-19 vaccines?
Yes. CDC has an FAQ page about COVID-19 vaccines specifically for healthcare providers: www.cdc.gov/vaccines/covid-19/hcp/faq.html. This page includes CDC answers related to vaccination programs, EUA, administration, storage and handling, and safety and efficacy.
Who is recommended to receive COVID-19 vaccines?
ACIP has made recommendations about which groups should be prioritized for vaccination while supplies are limited. Prioritization is based upon either risk factors for serious outcomes or risk of infection among workers in sectors considered essential to the functioning of society.
The highest priority recipients in ACIP's Phase 1a include all individuals who work in healthcare settings and the staff and residents of long term care facilities. On December 20, 2020, ACIP recommended that in Phase 1b, vaccine should be offered to people age 75 years or older and frontline essential workers (non–health care workers), and that in Phase 1c, people aged 65–74 years, people aged 16–64 years with high-risk medical conditions, and essential workers not recommended for vaccination in Phase 1b should be offered vaccine. All other people age 16 years and older not included in earlier groups are included in Phase 2. State and local public health authorities are responsible for implementation of vaccination programs and their programs may not follow these recommendations exactly. Updated prioritization recommendations were published on December 22, 2020: www.cdc.gov/mmwr/volumes/69/wr/pdfs/mm695152e2-H.pdf.
Should people who have had COVID-19 illness be vaccinated?
Yes. Vaccination should be offered to individuals regardless of history of prior SARS-CoV-2 infection. Viral testing to assess for current SARS-CoV-2 infection or serologic testing to assess for prior infection for the purposes of vaccine decision-making is not recommended.
As with all vaccines, vaccination should be deferred until after recovery from moderate to severe COVID-19 illness. In addition, to minimize the risk of exposing others to SARS-CoV-2 virus, vaccination generally should be deferred until criteria have been met for individuals with COVID-19 illness to discontinue isolation.
Vaccine Products Back to top
What is an Emergency Use Authorization (EUA)?
Under section 564 of the Federal Food, Drug, and Cosmetic Act (FD&C Act), the FDA Commissioner may allow unapproved medical products or unapproved uses of approved medical products to be used in an emergency to diagnose, treat, or prevent serious or life-threatening diseases or conditions caused by chemical, biological, radiological or nuclear threat agents when there are no adequate, approved, and available alternatives. Vaccines that receive an EUA may later be fully licensed by the FDA.
When will we have a VIS for the vaccines that have an EUA? What information am I supposed to give patients in writing?
For each COVID-19 vaccine authorized under an Emergency Use Authorization (EUA), the Food and Drug Administration (FDA) requires that vaccine recipients or their caregivers are provided with certain vaccine-specific EUA information to help make an informed decision about vaccination. This is accomplished by providing an EUA Fact Sheet for Recipients and Caregivers. The Fact Sheet is similar in purpose and content to vaccine information statements (VISs) for licensed vaccines but differs in that the EUA Fact Sheet is specific to each authorized COVID-19 vaccine, is developed by the manufacturer of the vaccine, and is authorized by the FDA.
There is no VIS for COVID-19 vaccines authorized under an EUA. Instead, the FDA-issued EUA Fact Sheet for Recipients and Caregivers for each COVID-19 vaccine must be used.
The Pfizer-BioNTech COVID-19 vaccine EUA Fact Sheet for Recipients and Caregivers is available here: www.fda.gov/media/144414/download.
The Moderna COVID-19 vaccine EUA Fact Sheet for Recipients and Caregivers is available here: www.modernatx.com/covid19vaccine-eua/eua-fact-sheet-recipients.pdf.
What are mRNA vaccines?
Both the Pfizer-BioNTech COVID-19 (BNT162b2) vaccine and the Moderna COVID-19 (mRNA-1273) vaccines are lipid nanoparticle-formulated, nucleoside-modified mRNA vaccines encoding the prefusion spike glycoprotein of SARS-CoV-2, the virus that causes coronavirus disease 2019. Visit this CDC website for more details about how mRNA vaccines work: www.cdc.gov/coronavirus/2019-ncov/vaccines/different-vaccines/mrna.html.
How well do the mRNA COVID-19 vaccines work?
The FDA EUA was issued based upon the short-term effectiveness of these vaccines at preventing symptomatic illness with COVID-19. The preliminary results of large phase 3 clinical trials for both vaccines were similar, demonstrating an overall efficacy of 94–95% in preventing symptomatic COVID-19 illness compared to placebo recipients.
Do COVID-19 vaccines prevent infection with SARS-CoV-2?
Definitive data are not yet available to answer the question of how well the mRNA COVID-19 vaccines prevent asymptomatic infection with the SARS-CoV-2 virus and subsequent transmission of the virus to others. For this reason, CDC currently recommends that vaccine recipients continue to follow the general recommendations to prevent the spread of COVID-19 related to wearing masks, practicing physical distancing, and maintaining good hand hygiene.
Where can I obtain detailed information about the Pfizer-BioNTech COVID-19 or the Moderna COVID-19 vaccine?
CDC has developed a "one-stop" product-specific webpage for each COVID-19 vaccine with all of the important details immunization providers need to know.
• Pfizer-BioNTech COVID-19 vaccine: www.cdc.gov/vaccines/covid-19/info-by-product/pfizer/index.html.
•   Moderna COVID-19 vaccine: www.cdc.gov/vaccines/covid-19/info-by-product/moderna/index.html.
In addition to CDC, each company has a detailed EUA Fact Sheet for Providers.
• Pfizer-BioNTech COVID-19 vaccine: www.fda.gov/media/144413/download
•   Moderna COVID-19 vaccine: www.fda.gov/media/144637/download
COVID-19 Vaccines for Adolescents and Adults Back to top
What ages are authorized to receive the available COVID-19 vaccines?
The Pfizer-BioNTech COVID-19 vaccine is authorized for emergency use in people age 16 years and older. The Moderna COVID-19 vaccine is authorized for emergency use in people age 18 years and older. Both companies have announced plans to pursue licensure of the vaccines in younger age groups as soon as they have sufficient data to support an application.
COVID-19 Vaccines and Pregnancy Back to top
Are COVID-19 vaccines recommended during pregnancy?
Pregnancy is not a contraindication or precaution for either the Moderna or Pfizer-BioNTech COVID-19 vaccines. Pregnant people are at increased risk of severe illness from COVID-19 compared to non-pregnant people of the same age. However, there is very limited information available on the use of either vaccine during pregnancy. There are currently few data on the safety of COVID-19 vaccines, including mRNA vaccines, in pregnant people. Limited data are currently available from animal developmental and reproductive toxicity studies: no safety concerns were demonstrated in these studies. Studies in pregnant people are underway and the vaccine manufacturers are following outcomes in people in the clinical trials who became pregnant. Based on current knowledge, experts believe that mRNA vaccines are unlikely to pose a risk to the expectant mother or the fetus. CDC and the American College of Obstetricians and Gynecologists (ACOG) recommend if pregnant people are part of a group that is recommended to receive a COVID-19 vaccine, they may choose to be vaccinated.
Vaccination should not be withheld from a pregnant person who is otherwise eligible for vaccination and chooses to be vaccinated.
There is no recommendation for routine pregnancy testing before receipt of a COVID-19 vaccine. Those who are trying to become pregnant do not need to avoid pregnancy after mRNA COVID-19 vaccination.
For more details about COVID-19 vaccination during pregnancy, visit CDC's webpage, Vaccine Considerations for People who are Pregnant: www.cdc.gov/coronavirus/2019-ncov/vaccines/recommendations/pregnancy.html.
Are COVID-19 vaccines recommended if the recipient is breastfeeding?
There are no data on the effects of mRNA COVID-19 vaccines on the breastfed infant or milk production/excretion. These vaccines are not thought to be a risk to the breastfeeding infant. A person who is lactating and part of a group recommended to receive an mRNA COVID-19 vaccine should be offered vaccination as appropriate and may choose to be vaccinated.
Administering Vaccines Back to top
How are mRNA vaccines administered?
CDC has prepared a quick reference guide for preparation and administration of each mRNA COVID-19 vaccine:
• Pfizer-BioNTech COVID-19 vaccine:
•   Moderna COVID-19 vaccine:
Has CDC provided clinical guidance on what to do if an error occurs while administering mRNA COVID-19 vaccinations?
Yes. On February 10, 2021, CDC published a new appendix to its "Interim Clinical Considerations for Use of mRNA Vaccines Currently Authorized in the United States." This appendix provides resources for preventing and reporting mRNA COVID-19 vaccine administration errors, as well as a simple table outlining actions to take after an error has occurred: www.cdc.gov/vaccines/covid-19/info-by-product/clinical-considerations.html#Appendix-A.
Errors addressed include the following:
• Incorrect route or site
•   Incorrect age
•   Incorrect dosing interval
•   Incorrect dose (high or low)
•   Administration after improper storage conditions
•   Administration after the expiration/beyond use date
•   Diluent errors (wrong diluent, too much or too little) with the Pfizer-BioNTech vaccine
A dose of mRNA COVID-19 vaccine was administered subcutaneously instead of by the intramuscular route. Does the dose need to be repeated?
No. CDC does not recommend repeating the dose of mRNA COVID-19 vaccine in circumstances where the dose is administered in an incorrect route or an incorrect site (i.e., not in the deltoid or anterolateral thigh).
During vaccination, the needle came loose and vaccine leaked out around it. Do we need to repeat the dose?
It depends on how much of the dose was successfully administered. If the patient received at least half of the authorized vaccine dose, do not repeat the dose. However, if less than half the dose was administered, revaccinate the recipient immediately (no minimum interval) with a full dose in the opposite arm.
Scheduling Vaccines Back to top
Where can I find the latest information on scheduling COVID-19 vaccines?
For detailed information on COVID-19 vaccine scheduling, refer to the CDC's interim clinical considerations for COVID-19 vaccination: www.cdc.gov/vaccines/covid-19/info-by-product/clinical-considerations.html.
What is the recommended schedule for mRNA COVID-19 vaccines?
The Pfizer-BioNTech COVID-19 vaccine is administered as a two-dose series, 21 days apart. Both doses should be the Pfizer-BioNTech vaccine.
The Moderna COVID-19 vaccine is administered as a two-dose series, 28 days apart. Both doses should be the Moderna vaccine.
Every effort should be made to administer the same brand for both doses. There are no data on the effectiveness of a mixed-brand vaccination series. In exceptional situations in which the first-dose vaccine product cannot be determined or is no longer available, any available mRNA COVID-19 vaccine may be administered at a minimum interval of 28 days between doses to complete the mRNA COVID-19 vaccination series. If two doses of different mRNA COVID-19 vaccine products are administered in these situations (or inadvertently), no additional doses of either product are recommended at this time.
If a patient does not come back on time for the second dose, do we need to re-start the vaccine series?
No. Simply administer the second dose to complete the series.
What if the patient gets the second dose early?
Second doses administered within a grace period of 4 days or fewer from the recommended date for the second dose are considered valid; however, doses administered earlier do not need to be repeated.
If the second dose of vaccine may be given before the recommended interval because of the 4-day grace period, should we offer that option routinely?
No. CDC states that people should not be scheduled to receive dose 2 earlier than recommended (21 days for Pfizer-BioNTech, 28 days for Moderna). Schedulers should offer second dose appointments beginning on the date of the recommended interval or later. CDC guidance allows for dose 2 to be given up to 4 days before the recommended interval in order to avoid missed vaccination opportunities when a recipient unexpectedly arrives early and might not return on schedule. The series never needs to be restarted due to a delay in the second dose.
If a patient inadvertently received a different brand of mRNA vaccine as a second dose, does it need to be repeated with the correct brand?
There are no data on the safety or efficacy of a mixed-brand mRNA vaccine schedule. For this reason, both doses in the series should be the same brand. However, if a recipient is inadvertently given a different brand of mRNA vaccine for the second dose, the CDC does not currently recommend that the patient receive a repeat dose of either product.
What should be done if a patient scheduled for vaccination is exposed to COVID-19 and quarantined or is isolated for suspected or confirmed SARS-CoV-2 infection?
In general, the people scheduled for COVID-19 vaccination who are exposed to SARS-CoV-2 virus and quarantined should reschedule vaccination after their quarantine period has ended in order to avoid the risk of exposing vaccinators to the virus.
People diagnosed with SARS-CoV-2 infection before a scheduled vaccination should defer vaccination until after recovery and the end of the isolation period to avoid the risk of exposing vaccinators to the virus.
Can COVID-19 vaccine recipients be given other vaccines at the same visit?
There are no data on the safety and efficacy of mRNA COVID-19 vaccines administered with any other vaccine. For this reason, CDC currently recommends that the mRNA COVID-19 vaccine series should be administered alone, and not within 14 days before or after any other vaccination. However, mRNA COVID-19 and other vaccines may be administered at shorter intervals if the benefits of vaccination are judged to outweigh any unknown potential risks of vaccine coadministration. Examples of such situations include tetanus vaccination as a part of wound management, vaccination in response to a measles or hepatitis A outbreak, or COVID-19 vaccination of a person in a long-term care facility or healthcare setting who recently received influenza or other vaccinations (to avoid delays or missed opportunities for COVID-19 vaccination). If mRNA COVID-19 vaccines are administered within 14 days of another vaccine, doses do not need to be repeated for either vaccine.
My patient is due for a second dose of recombinant zoster vaccine (Shingrix, GSK). However, the patient is eligible to receive COVID-19 vaccine and wants to be vaccinated against COVID-19 as soon as possible. What should we advise our patient about scheduling the second Shingrix dose?
Advise your patient to schedule the second Shingrix dose at least 14 days after receiving the second mRNA COVID-19 vaccination.
A patient had a routine tuberculin skin test (TST) placed the day before the patient's appointment for a first dose of COVID-19 vaccine. Should we proceed with vaccination or do we need to reschedule?
COVID-19 vaccination may take place on the same day or any day after a TST is placed. A TST will not interfere with the response to vaccination. The reliability of a TST is expected to be unchanged if a TST is placed before or simultaneously with COVID-19 vaccination. The reliability of a negative TST or interferon gamma release assay (IGRA) soon after COVID-19 vaccination has not been studied.
COVID-19 vaccination should not be delayed because of testing for tuberculosis (TB) infection. A TST is not a vaccine and is not subject to the general recommendation for an interval of at least 14 days between mRNA COVID-19 vaccination and administration of any other vaccine. If not administered on the same day, CDC recommends that a TST be delayed at least 4 weeks after completion of COVID-19 vaccination because the reliability of a negative TST result soon after mRNA COVID-19 vaccination is unknown.
For additional details on mRNA COVID-19 vaccination of patients being evaluated for active tuberculosis, refer to CDC clinical considerations for mRNA vaccines and laboratory testing: www.cdc.gov/vaccines/covid-19/info-by-product/clinical-considerations.html#laboratory-testing.
How does the use of monoclonal antibodies to treat symptomatic COVID-19 affect the scheduling of mRNA COVID-19 vaccination?
There are no data on the effect of passive antibody therapies for COVID-19, including monoclonal antibodies and convalescent plasma, on the effectiveness of vaccination with mRNA COVID-19 vaccines. As a precautionary measure, CDC recommends waiting at least 90 days after receipt of passive antibody therapy for COVID-19 illness before initiating the COVID-19 vaccine series. Individuals who develop COVID-19 illness after the first COVID-19 vaccination and receive passive antibody therapy should wait 90 days after antibody therapy to receive the second dose. There is no need to restart the vaccination series.
Antibody therapies not specific to COVID-19 treatment (e.g., intravenous immunoglobulin, RhoGAM) are unlikely to substantially impair development of a protective antibody response to COVID-19 vaccination. Thus, there is no recommended minimum interval between antibody therapies not specific to COVID-19 treatment and mRNA COVID-19 vaccination.
Contraindications and Precautions Back to top
Please describe the contraindications for mRNA COVID-19 vaccination.
CDC considers a history of the following to be a contraindication to vaccination with both the Pfizer-BioNTech and Moderna COVID-19 vaccines:
• Severe allergic reaction (e.g., anaphylaxis) after a previous dose of an mRNA COVID-19 vaccine or any of its components
•   Immediate allergic reaction of any severity to a previous dose of an mRNA COVID-19 vaccine or any of its components (including polyethylene glycol [PEG])*
•   Immediate allergic reaction of any severity to polysorbate (due to potential cross-reactive hypersensitivity with the vaccine ingredient PEG)*
* These people should not receive mRNA COVID-19 vaccination at this time unless they have been evaluated by an allergist-immunologist and it is determined that they can safely receive the vaccine (e.g., under observation, in a setting with advanced medical care available).
CDC has published a table with additional details about the components of both mRNA COVID-19 vaccines: www.cdc.gov/vaccines/covid-19/info-by-product/clinical-considerations.html#Appendix-C.
People with an immediate allergic reaction to the first dose of an mRNA COVID-19 vaccine should not receive additional doses of either of the mRNA COVID-19 vaccines. CDC has provided a chart to assist in the evaluation of immediate reactions to vaccination: www.cdc.gov/vaccines/covid-19/info-by-product/clinical-considerations.html#Appendix-D.
What are the precautions to mRNA COVID-19 vaccination?
CDC considers a history of any immediate allergic reaction to any other vaccine or injectable therapy (defined as intramuscular, intravenous, or subcutaneous vaccines or therapies [excluding subcutaneous immunotherapy for allergies, known as "allergy shots"] not related to a component of mRNA COVID-19 vaccines or polysorbate) as a precaution but not a contraindication to vaccination for both the Pfizer-BioNTech and Moderna COVID-19 vaccines. These precautions based on history, as defined, include people with a reaction to a vaccine or injectable therapy that contains multiple components, one of which is PEG, another vaccine component, or polysorbate, but in whom it is unknown which component caused the immediate allergic reaction.
Individuals with a precaution to vaccination should be counseled about the unknown risks of experiencing a severe allergic reaction and balance these risks against the benefits of vaccination. Deferral of vaccination and/or consultation with an allergist-immunologist may be considered until further information on the risk of anaphylaxis is available.
The following considerations can be used to help assess the risk for mRNA COVID-19 vaccination in these individuals:
• Risk of exposure to SARS-CoV-2
•   Risk of severe disease or death due to COVID-19
•   Whether the patient has previously been infected with SARS-CoV-2 and, if so, how long ago; because reinfection is uncommon in the months following infection, a person with a precaution to vaccination and recent COVID-19 illness may choose to delay vaccination until further information is known about the risk of anaphylaxis following vaccination
•   The unknown risk of anaphylaxis following mRNA COVID-19 vaccination in a person with a history of an immediate allergic reaction to other vaccines or injectable therapies
•   Ability of the patient to be vaccinated in a setting where appropriate medical care is immediately available for anaphylaxis
For additional guidance about contraindications and precautions, please refer to www.cdc.gov/vaccines/covid-19/info-by-product/clinical-considerations.html#Contraindications.
Can people who are immunocompromised or who have autoimmune disease be vaccinated with mRNA COVID-19 vaccines?
Yes, they may choose to be vaccinated as long as they do not have a contraindication to vaccination. Please see detailed considerations about vaccination of people with underlying medical conditions here: www.cdc.gov/vaccines/covid-19/info-by-product/clinical-considerations.html#underlying-conditions.
Are there any common types of allergies that are neither contraindications nor precautions to vaccination?
Allergic reactions (including severe allergic reactions such as anaphylaxis) that are not related to vaccines, injectable therapies, components of mRNA COVID-19 vaccines (including PEG), or polysorbates are not a contraindication or precaution to vaccination with either mRNA COVID-19 vaccine. Examples of other allergies that are not a contraindication or precaution include other food, pet, venom, or environmental allergies, or allergies to oral medications (including the oral equivalents of injectable medications). The vial stoppers of these mRNA vaccines are not made with natural rubber latex, so there is no contraindication or precaution to vaccination for persons with a latex allergy. In addition, mRNA COVID-19 vaccines do not contain eggs or gelatin.
A vaccine recipient reported experiencing a red, itchy, swollen patch of skin that developed several days after vaccination around the injection site of her first Moderna vaccine dose. It resolved after a few days. Is this a contraindication? Should this alter our plans for dose two?
She should receive dose two as recommended. Individuals with only a delayed-onset local reaction (e.g., redness, induration, itching) around the injection site area after the first vaccine dose do not have a contraindication or precaution to the second dose. Some people have reported delayed-onset local reactions, including Moderna clinical trial participants, beginning a few days through the second week after the first dose. The reactions are sometimes quite large but are self-limited. It is not known whether individuals who experienced a delayed-onset injection site reaction after the first dose will experience a similar reaction after the second dose. However, these reactions are not believed to represent an increased risk for anaphylaxis after a subsequent dose. Thus, individuals with such delayed injection site reactions after the first mRNA COVID-19 vaccine dose should receive the second dose using the same vaccine product as the first dose and at the recommended interval, preferably in the opposite arm.
Patients concerned about the risk of allergic reaction or side effects following COVID-19 vaccination are asking if they should take acetaminophen and/or antihistamines before receiving mRNA COVID-19 vaccination. What does CDC advise?
Medications to reduce fever and pain (e.g., acetaminophen, non-steroidal anti-inflammatory drugs) may be taken to treat post-vaccination local or systemic symptoms, if medically appropriate. However, routine administration of such medications before vaccination is not currently recommended because information on the impact of such use on mRNA COVID-19 vaccine-induced antibody responses is not available at this time.
In addition, administration of antihistamines before mRNA COVID-19 vaccination to prevent allergic reactions is not recommended. Antihistamines do not prevent anaphylaxis, and their use might mask cutaneous symptoms, which could delay diagnosis and management of anaphylaxis.
Vaccine Safety Back to top
What side effects are expected after vaccination with mRNA vaccines?
Recipients of mRNA COVID-19 vaccines often experience local (e.g., pain, swelling, redness at the injection site, localized swollen lymph nodes in the armpit of the vaccinated arm) or systemic (e.g., fever, fatigue, headache, chills, body and joint aches) post-vaccination symptoms. Depending on vaccine product (Pfizer-BioNTech vs. Moderna), age group, and vaccine dose, approximately 80–89% of vaccinated people develop at least one local symptom and 55–83% develop at least one systemic symptom following vaccination.
Most systemic post-vaccination symptoms are mild to moderate in severity, occur within the first three days of vaccination, and resolve within 1–3 days of onset. These symptoms are more frequent and severe following the second dose and among younger people compared to older people.
I have heard of people who have experienced anaphylaxis or other allergic-type reactions following vaccination with the mRNA COVID-19 vaccines. How should patients with allergies presenting for COVID-19 vaccination be evaluated?
Serious allergic reactions, such as anaphylaxis, in the minutes following vaccination are rare but are possible with any vaccine. Every vaccination site should have staff available who are trained and equipped to recognize and respond to signs of anaphylaxis in a vaccine recipient. See this CDC website for additional information about preparing for the management of anaphylaxis: www.cdc.gov/vaccines/covid-19/info-by-product/pfizer/anaphylaxis-management.html.
CDC and FDA are investigating reports of allergic reactions following vaccination with mRNA COVID-19 vaccines and are updating their screening recommendations as new information becomes available.
An immediate allergic reaction to any component or previous dose of an mRNA COVID-19 vaccine is a contraindication to vaccination with both the Pfizer-BioNTech and Moderna vaccines. Please see this CDC chart of vaccine components designed to assist the triage of patients with various health conditions or allergies: www.cdc.gov/vaccines/covid-19/info-by-product/clinical-considerations.html#Appendix-C.
How long should patients be observed for signs of an immediate allergic reaction following vaccination with a mRNA COVID-19 vaccine?
People with a history of an immediate allergic reaction of any severity to a vaccine or injectable therapy and people with a history of anaphylaxis due to any cause should be observed for 30 minutes. All other people should be observed for 15 minutes.
Where can I find the latest information on allergic reactions and COVID-19 vaccines?
Visit this CDC website for the latest information: www.cdc.gov/coronavirus/2019-ncov/vaccines/safety/allergic-reaction.html.
I have heard that the FDA has specific reporting requirements for healthcare providers who administer COVID-19 vaccines under EUA. What are they?
Adverse events that occur in a recipient following mRNA COVID-19 vaccination should be reported to the Vaccine Adverse Event Reporting System (VAERS). Vaccination providers are required by the FDA to report the following that occur after mRNA COVID-19 vaccination under Emergency Use Authorization:
• Vaccine administration errors
•   Serious adverse events
•   Cases of Multisystem Inflammatory Syndrome
•   Cases of COVID-19 that result in hospitalization or death
Reporting is encouraged for any other clinically significant adverse event even if it is uncertain whether the vaccine caused the event. Information on how to submit a report to VAERS is available at https://vaers.hhs.gov or by calling 1-800-822-7967.
How is the safety of COVID-19 vaccines being monitored?
Multiple national surveillance systems are being used to monitor the safety of new COVID-19 vaccines in different ways. Please see this CDC website for additional information on each system: www.cdc.gov/coronavirus/2019-ncov/vaccines/safety.html.
What is v-safe?
CDC's v-safe program is a smartphone-based tool that uses text messaging and web surveys to provide personalized health check-ins after a person receives a COVID-19 vaccination. It also provides second dose reminders. Participation is voluntary. Vaccine recipients may sign up for the program after receiving the first dose. For more information, visit www.cdc.gov/coronavirus/2019-ncov/vaccines/safety/vsafe.html.
Is compensation for an injury resulting from an EUA COVID-19 vaccine available through the National Vaccine Injury Compensation Program (VICP)?
No. The EUA COVID-19 vaccines are not part of the VICP. The EUA COVID-19 vaccines are part of a similar program called the Countermeasures Injury Compensation Program (CICP). For more information, visit this web page: www.hrsa.gov/cicp.
Storage and Handling Back to top
Where can I find details about the storage and handling of COVID-19 vaccines?
You may find guidance on the storage and handling of COVID-19 vaccines in the CDC's Vaccine Storage and Handling Toolkit addendum on COVID-19 vaccines: www.cdc.gov/vaccines/hcp/admin/storage/toolkit/storage-handling-toolkit.pdf.
IAC has assembled key COVID-19 vaccine storage and handling resources in its section on Clinic Resources and Tools at our Vaccines: COVID-19 main page: www.immunize.org/covid-19/#tools.
Under what conditions may we transport mRNA COVID-19 vaccines? Is transport of a partial vial or predrawn syringe ever permissible?
Although routine transportation of vaccines to different facilities is not generally recommended, there are times when this is necessary. CDC recommends transporting mRNA COVID-19 vaccine in vials and always with a continuous temperature monitoring device to ensure adherence to authorized storage times and temperatures. Because liquid mRNA COVID-19 vaccines should not be shaken vigorously, it is preferred to transport vials in their solid frozen state, if possible, or to initiate transport while they are frozen. Moderna recommends that thawed vials of liquid be cushioned to minimize agitation during transport. Thawed vaccine should never be refrozen. A partially used vial may be transported (e.g., in the process of vaccinating homebound individuals), but cannot be transferred from one provider to another nor can it be transported across state lines. Details are provided in the 2021 CDC Vaccine Storage and Handling Toolkit addendum on mRNA COVID-19 vaccines: www.cdc.gov/vaccines/hcp/admin/storage/toolkit/storage-handling-toolkit.pdf.
There may be instances when the only option is to transport vaccine in a predrawn syringe. CDC refers to the U.S. Pharmacopeia (USP) guidance for transporting predrawn vaccine in syringes on page 11 of the USP COVID-19 Vaccine Toolkit: Operational Considerations for Healthcare Practitioners. The complete document provides detailed guidance on mRNA COVID-19 vaccine transport and is available for download from this site: www.usp.org/covid-19/vaccine-handling-toolkit.
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This page was updated on February 20, 2021.
This page was reviewed on February 20, 2021.
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Immunization Action Coalition  •  2550 University Avenue West  •  Suite 415 North  •  Saint Paul, Minnesota  •  55114
tel 651-647-9009  •  fax 651-647-9131
This website is supported in part by a cooperative agreement from the National Center for Immunization and Respiratory Diseases (Grant No. 6NH23IP22550) at the Centers for Disease Control and Prevention (CDC) in Atlanta, GA. The website content is the sole responsibility of IAC and does not necessarily represent the official views of CDC.