Clinical Guidance for COVID-19 Vaccination

Three COVID-19 vaccinespdf icon vaccines are currently approved under a Biologics License Application (BLA) or authorized under an Emergency Use Authorization (EUA) by the U.S. Food and Drug Administration (FDA) (Table 1) (Box 1):

• Pfizer-BioNTech COVID-19 Vaccine/COMIRNATY (hereafter referred to as Pfizer-BioNTech in this document)¹
• Moderna COVID-19 Vaccine/SPIKEVAX (hereafter referred to as Moderna in this document)²
• Janssen (Johnson & Johnson) COVID-19 Vaccine

For primary and booster vaccination for all populations, an mRNA COVID-19 vaccine series is preferred over the Janssen COVID-19 Vaccine. The mRNA COVID-19 vaccines are feasible for use in most vaccine-eligible populations or settings. However, offering the Janssen COVID-19 Vaccine is preferable to not providing any COVID-19 vaccine.

The Pfizer-BioNTech and Moderna vaccines are lipid nanoparticle-formulated, nucleoside-modified mRNA vaccines encoding the prefusion spike glycoprotein of SARS-CoV-2, the virus that causes COVID-19. The Janssen COVID-19 Vaccine is a recombinant, replication-incompetent adenovirus type 26 (Ad26) vector encoding the stabilized prefusion spike glycoprotein of SARS-CoV-2. None of the currently FDA-approved or FDA-authorized COVID-19 vaccines are live-virus vaccines.

Table 1. COVID-19 vaccine formulations currently approved or authorized in the United States

For information on the formulations, storage and handling, preparation, and administration of COVID-19 vaccines, see U.S. COVID-19 Vaccine Product Information.

COVID-19 vaccination is recommended for everyone ages 5 years and older in the United States for the prevention of COVID-19. The age groups approved under BLA or authorized under EUA to receive vaccination vary by vaccine product. CDC recommends that people get up to date with COVID-19 vaccination as soon as feasible, which includes the completed primary series and any recommended booster doses for which they are eligible.

COVID-19 vaccine use terminology, including for primary series vaccination and booster vaccination, is defined below (BOX 2).

There is currently no FDA-approved or FDA-authorized COVID-19 vaccine for children ages 4 years and younger. These children should not receive any COVID-19 vaccine doses (including partial doses of vaccine formulations approved or authorized for people ages 5 years and older) at this time unless part of a clinical trial.

See appendices A (People who received COVID-19 vaccine outside the United States) and B (People who received COVID-19 Vaccine as part of a clinical trial) for recommendations on these topics.

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mRNA COVID-19 vaccines

The mRNA COVID-19 vaccines are administered as a:

The same mRNA vaccine product should be used for all doses of the primary series (see Interchangeability of COVID-19 vaccine products).

Pfizer-BioNTech COVID-19 Vaccine is FDA-approved or FDA-authorized in people ages 5 years and older as a 2-dose primary series, with an interval of 3 weeks between doses (Table 2). Vaccination providers should ensure the correct age-appropriate formulation is administered based on the recipient’s age on the day of vaccination (Table 1).

Moderna COVID-19 Vaccine is FDA-approved or FDA-authorized in people ages 18 years and older as a 2-dose primary series, with an interval of 4 weeks between doses (Table 2).

Table 2. COVID-19 vaccination schedule for the general population*

Considerations for intervals for mRNA COVID-19 vaccine primary series

mRNA COVID-19 vaccines are FDA-approved or authorized for a 3-week (Pfizer-BioNTech vaccine) or 4-week (Moderna vaccine) interval between the first and second dose. A 3- or 4-week interval continues to be the recommended interval for people who are moderately to severely immunocompromised, adults ages 65 years and older, and others who need rapid protection due to increased concern about community transmission or risk of severe disease. mRNA COVID-19 vaccines are safe and effective at the FDA-approved or FDA-authorized intervals, but a longer interval may be considered for some populations. While absolute risk remains small, the relative risk for myocarditis is higher for males ages 12-39 years, and this risk might be reduced by extending the interval between the first and second dose. Some studiespdf icon in adolescents (ages 12-17 years) and adults have shown the small risk of myocarditis associated with mRNA COVID-19 vaccines might be reduced and peak antibody responses and vaccine effectiveness may be increased with an interval longer than 4 weeks. Extending the interval beyond 8 weeks has not been shown to provide additional benefit. There are currently no data available for children ages 11 years and younger. Therefore, an 8-week interval may be optimal for some people ages 12 years and older, especially for males ages 12–39 years.

Janssen COVID-19 Vaccine

Although mRNA vaccines are preferentially recommended in most situations over the Janssen COVID-19 Vaccine, the Janssen COVID-19 Vaccine may be considered in some situations. See Contraindications and precautions and Safety considerations for Janssen COVID-19 Vaccine.

Janssen COVID-19 Vaccine is FDA-authorized for use in people ages 18 years and older. The primary series is a single primary dose. See Appendix D for additional information about completing schedules that have included use of the Janssen COVID-19 vaccine in people who are moderately or severely immunocompromised.

All people ages 12 years and older should receive an age-appropriate booster dose and formulation of COVID-19 vaccine (Table 2), even if they were age 11 years or younger at the time of the primary series. Currently, COVID-19 vaccines are not authorized for a booster dose for children ages 11 years and younger.

An mRNA COVID-19 vaccine is preferred over the Janssen COVID-19 Vaccine for booster vaccination. In people ages 12–17 years, only Pfizer-BioNTech COVID-19 Vaccine can be used.

The recommended interval for the booster dose is based on the product received for the primary series. In most people, the interval is:

• At least 5 months after mRNA 2-dose primary vaccination or
• At least 2 months after Janssen single dose primary vaccination

For information about schedules and booster doses for people who are moderately or severely immunocompromised, see guidance for COVID-19 vaccination for people who are moderately or severely immunocompromised.

Doses administered up to 4 days before the minimum interval, known as the 4-day grace period, are considered valid. If a dose is administered prior to the 4-day grace period and is a:

• Primary series dose, it should be repeated; the repeat dose should be spaced from the date of the dose given in error by the recommended minimum interval.
• Booster dose; it should not be repeated (see Appendix C for more details).

Doses administered at any time after the recommended interval are valid.

In general, the same mRNA vaccine product (i.e., the same manufacturer) should be used for all doses in the primary series.

Any product can be used for a booster dose (i.e., heterologous booster dose) for those ages 18 years and older. Only Pfizer-BioNTech COVID-19 Vaccine can be used for people ages 12-17 years old.

COVID-19 vaccines may be administered without regard to timing of other vaccines.

This includes simultaneous administration of COVID-19 vaccine and other vaccines on the same day. If multiple vaccines are administered at a single visit, administer each injection in a different injection site.

Best practices for multiple injections include:

• Label each syringe with the name and the dosage (amount) of the vaccine, lot number, initials of the preparer, and exact beyond-use time, if applicable.
• Separate injection sites by 1 inch or more, if possible.
• Administer the COVID-19 vaccine and vaccines that may be more likely to cause a local reaction in different limbs, if possible.

See ACIP’s general best practices and Epidemiology and Prevention of Vaccine-Preventable Diseases (Pink Book) for further information.

People with immunocompromising conditions or people who take immunosuppressive medications or therapies are at increased risk for severe COVID-19. Because the immune response following COVID-19 vaccination may differ in moderately or severely immunocompromised people, specific guidance for this population is provided. Use of mRNA vaccines is preferred.

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Note: Timeline is approximate. Intervals of 3 months or fewer are converted into weeks per the formula “1 month = 4 weeks”. Intervals of 4 months or more are converted into calendar months.

*An mRNA COVID-19 vaccine is preferred over the Janssen COVID-19 Vaccine for booster vaccination of people ages 18 years and older. For people ages 12–17 years, only Pfizer-BioNTech can be used. People ages 5–11 years should not receive a booster dose.

†Only Pfizer-BioNTech or Moderna COVID-19 Vaccine should be used. See Appendix D for more information on vaccinating people who are moderately or severely immunocompromised and who received Janssen COVID-19 Vaccine for the primary series.

mRNA COVID-19 vaccines

A 3-dose primary series is recommended for people ages 5 years and older who are moderately or severely immunocompromised at the time of vaccination (Table 3). The same mRNA vaccine product should be used for all doses of the primary series (see Interchangeability of COVID-19 vaccine products).

Janssen COVID-19 Vaccine

A primary Janssen vaccine dose is recommended for people ages 18 years and older who are moderately or severely immunocompromised, followed by a second (additional) dose using an mRNA COVID-19 vaccine at least 4 weeks later (see Appendix D for additional information). If Moderna COVID-19 vaccine is used for the second dose, administer a 100 µg (0.5 ml) dose.

Booster doses are recommended for people 12 years of age and older after completion of primary vaccination.

Special situation: Many recipients of Janssen COVID-19 Vaccine may have already received a booster dose (Pfizer-BioNTech, Moderna [50 µg, 0.25 ml], or Janssen vaccine), without having had the second (additional) mRNA vaccine dose. In this situation, regardless of type and timing of vaccine received as the second dose, administer a Pfizer-BioNTech vaccine or a Moderna vaccine (100 µg [0.5 mL]) as the third dose at least 2 months after dose 2. See Appendix D for additional dose information for Janssen COVID-19 Vaccine recipients.

Table 3: COVID-19 vaccination schedule for people who are moderately or severely immunocompromised*

Moderate and severe immunocompromising conditions and treatments include but are not limited to:

Factors to consider in assessing the general level of immune competence in a patient include disease severity, duration, clinical stability, complications, comorbidities, and any potentially immune-suppressing treatment. Age or place of residence alone (e.g., residence in a long-term care settingexternal icon), independent of a patient’s medical condition, should not be used to determine the level of immune competence, as the balance of benefits and risks of a third primary dose for people who are not moderately or severely immunocompromised is currently unknown.

Revaccination is defined as repeating a dose(s) of vaccine. Recipients of HCT or CAR-T-cell therapy who received one or more doses of COVID-19 vaccine prior to or during treatment should be revaccinated (i.e., complete primary vaccination and any recommended additional or booster doses) for any dose(s) received before or during treatment. Any revaccination doses should be given with an mRNA vaccine, regardless of vaccine administered for initial vaccination, and should start at least 3 months (12 weeks) after transplant or CAR-T-cell therapy. A patient’s clinical team is best positioned to determine the degree of immune compromise, need for revaccination, and appropriate timing of revaccination.

Whenever possible, COVID-19 vaccines should be administered at least 2 weeks before initiation or resumption of immunosuppressive therapies. Timing of COVID-19 vaccination should take into consideration current or planned immunosuppressive therapies and optimization of both the patient’s medical condition and response to vaccine.

The utility of serologic testingexternal icon or cellular immune testing to assess immune response to vaccination and guide clinical care has not been established. Serologic testing or cellular immune testing outside of the context of research studies is not recommended at this time.

People can self-attest to their moderately to severely immunocompromised status and receive COVID-19 vaccine doses wherever vaccines are offered. Vaccinators should not deny COVID-19 vaccination to a person due to lack of documentation.

On a case-by-case basis, providers of moderately or severely immunocompromised patients may administer mRNA COVID-19 vaccines outside of the FDA and CDC dosing intervals based on clinical judgment when the benefits of vaccination are deemed to outweigh the potential and unknown risks for the recipient. However, providers should not routinely administer additional doses of COVID-19 vaccine beyond those recommended in this guidance. Providers should consult treatment guidelinespdf iconexternal icon for use of monoclonal antibodies as pre-exposure prophylaxis for moderately or severely immunocompromised people who may not mount an immune response to COVID-19 vaccination.

ACIP’s general best practices for vaccination of people with altered immunocompetence, the CDC Yellow Book, and the Infectious Diseases Society of America policy statement, 2013 IDSA Clinical Practice Guideline for Vaccination of the Immunocompromised Hostexternal icon, can be consulted for additional information about the degree of immune suppression associated with different medical conditions and treatments.

Vaccinated people who are immunocompromised should be counseled about the potential for a reduced immune response to COVID-19 vaccines.  They and their close contacts should continue to follow current prevention measures.

This section summarizes special considerations for COVID-19 vaccination of children and adolescents.

Children should receive the age-appropriate vaccine formulation and follow the schedule based on their age on the day of vaccination, regardless of their size or weight (Table 1; Table 2; Table 3). Children ages 5–11 years should receive the 10 µg Pfizer-BioNTech COVID-19 Vaccine (orange cap) formulation and adolescents ages 12 years and older should receive the 30 µg Pfizer-BioNTech COVID-19 Vaccine (purple or gray cap) formulation.

If a child turns 12 years old between their first and second dose, they should receive the age-appropriate 30 µg Pfizer-BioNTech COVID-19 Vaccine (purple or gray cap) formulation for their second dose. However, the FDA authorizationexternal icon allows children who will turn from age 11 years to 12 years between their first and second dose in the primary regimen to receive, for either dose: (1) the Pfizer-BioNTech COVID-19 Vaccine formulation for children ages 5–11 years (each 0.2 mL dose containing 10 µg in an orange cap vial); or (2)  the Pfizer-BioNTech COVID-19 Vaccine formulation authorized for use in people ages 12 years and older (each 0.3 mL dose containing 30 µg in a purple cap or gray cap vial). If such dosing occurred, the child has completed their primary series. This is not considered an error and VAERS reporting is not indicated.

Myocarditis

Myocarditis is a rare, serious adverse event that has been reported primarily after receipt of the second dose of mRNA COVID-19 vaccines, with the highest risk currently observed in males ages 12–29 years. FDA has authorized and ACIP and CDC have recommended Pfizer-BioNTech vaccines in children ages 5–11 years and adolescents ages 12–17 years based on the determination that the benefits of COVID-19 vaccination outweigh risks in these populations. Extending the interval between the first and second mRNA vaccine dose to 8 weeks might reduce the risk. For additional information, see Safety considerations for mRNA COVID-19 vaccines: Pfizer-BioNTech and Moderna.

Pre-vaccination counseling

The vaccine-specific Fact Sheet for Recipients and Caregivers (Pfizer-BioNTech,external icon  Modernaexternal icon, Janssenexternal icon) should be provided to all vaccine recipients, parents or guardians, and caregivers (when relevant) before vaccination with any currently FDA-approved or FDA-authorized COVID-19 vaccine. They should be informed that mRNA vaccines are preferred over the Janssen COVID-19 Vaccine and that there is a risk of thrombosis with thrombocytopenia syndrome (TTS) following receipt of the Janssen COVID-19 Vaccine. Those who elect to receive the Janssen COVID-19 Vaccine should be informed about the risk and symptoms of TTS that can occur (typically in the 2 weeks after vaccination), as well as the need to seek immediate medical care should symptoms develop.

Potential for local and systemic reactions

Before vaccination, providers should counsel COVID-19 vaccine recipients, parents, or guardians about expected local (e.g., pain, swelling, erythema at the injection site) and systemic (e.g., fever, fatigue, headache, chills, myalgia, arthralgia) post-vaccination reactions. Localized axillary lymphadenopathy⁴ on the same side as the vaccinated arm has been observed following vaccination with mRNA COVID-19 vaccines.

Anaphylactic reactions have been rarely reported following receipt of COVID-19 vaccines. Administration of antihistamines to COVID-19 vaccine recipients before vaccination to prevent allergic reactions is not generally recommended. However, while antihistamines will not prevent anaphylaxis, some experts advise antihistamine use as a means of preventing milder allergic reactions in patients who might be at higher risk for allergic reactions.

Management of post-COVID-19-vaccination symptoms

For all currently FDA-approved or FDA-authorized COVID-19 vaccines, antipyretic or analgesic medications can be taken for the treatment of post-vaccination local or systemic symptoms, if medically appropriate; these medications should not be used prophylactically for the purposes of prevention of post-vaccination symptoms. However, in general, aspirin is not recommended for use in children and adolescents ages 17 years and younger as an antipyretic or analgesic due to the risk of Reye’s syndrome.

Additional guidance is available for assessing and responding to post-vaccination signs and symptoms in workplaces, including healthcare settings, and among long-term care facility residents.

Vaccination and SARS-CoV-2 testing

Antibody testing is not currently recommended to assess the need for vaccination in an unvaccinated person or to assess immunity to SARS-CoV-2 following COVID-19 vaccination. If antibody testing was done, vaccination with the primary series, an additional dose, or a booster dose should be completed as recommended regardless of the antibody test result. SARS-CoV-2 antibody tests currently authorized under an EUAexternal icon have variable performance characteristics and limitations. Furthermore, serologic correlates of protection have not been established and antibody testing does not evaluate the cellular immune response.

Screening testing and vaccination

Unvaccinated people who are being screened for SARS-CoV-2 infection (e.g., work, school, travel requirement) may be vaccinated at the time of screening if they do not have symptoms consistent with COVID-19.

Interpretation of SARS-CoV-2 test results in vaccinated people

Prior receipt of a COVID-19 vaccine will not affect the results of SARS-CoV-2 viral tests (nucleic acid amplification or antigen tests). To evaluate for antibody evidence of prior infection in vaccinated people (e.g., for public health surveillance or the diagnosis of MIS-C or MIS-A), a test that specifically detects IgM/IgG to the nucleocapsid protein should be used.

CDC considers the following to be contraindications and precautions to vaccination with COVID-19 vaccines:

Table 4. Contraindications and recommended action(s)

Table 5. Precautions and recommended action(s)

*Additionally, people with a history of an episode of immune-mediated syndrome characterized by thrombosis and thrombocytopenia, such as spontaneous or classic HIT, should not receive Janssen COVID-19 Vaccine. These people should receive an mRNA COVID-19 vaccine.

• Possible anaphylaxis, a progressive life-threatening reaction that typically includes urticaria but also with other symptoms such as wheezing, difficulty breathing, or low blood pressure (see Appendix E)
• Any angioedema affecting the airway (i.e., tongue, uvula, or larynx)
• Diffuse rash which also involves mucosal surfaces (e.g., Stevens-Johnson Syndrome)

Non-severe allergic reactions include:

• Urticaria beyond the injection site
• Angioedema involving lips, facial skin, or skin in other locations. NOTE: Any angioedema affecting the airway (i.e., tongue, uvula, or larynx) is considered a severe allergic reaction (see above)

Healthcare professionals or health departments in the United States can request a consultation from the Clinical Immunization Safety Assessment COVIDvax project for a complex COVID-19 vaccine safety question not readily addressed by CDC guidance.

See:

• Appendix E for triage of people with a history of allergies or allergic reactions
• Appendix F for a list of ingredients in COVID-19 vaccines
• Managing Anaphylaxis for information on allergic reactions, including severity of allergic reactions

Risk assessment: The following considerations can be used to help the vaccination provider conduct a risk assessment for vaccination in people with a precaution to vaccination because of allergy:

• Risk of exposure to SARS-CoV-2 virus (e.g., because of occupational or institutional setting)
• Risk of severe disease or death due to COVID-19 (e.g., because of age, underlying medical conditions)
• The unknown risk of anaphylaxis following COVID-19 vaccination in a person with a history of an immediate allergic reaction to other vaccines or injectable therapies. Consultation with an allergist-immunologist may help to clarify the risk assessment for these people.
• Ability of the patient to be vaccinated in a setting where appropriate medical care is immediately available for anaphylaxis. For people with a contraindication due to allergy to one type of COVID-19 vaccines (e.g., mRNA vaccines), who are receiving another type (e.g., Janssen vaccine) and for people with an immediate, non-severe allergic reaction after a previous dose of COVID-19 vaccine who are receiving vaccination with a subsequent dose of that COVID-19 vaccine type, vaccination should only be undertaken in an appropriate setting under the supervision of a healthcare professional experienced in the management of severe allergic reactions. Consultation with an allergist-immunologist may help to clarify the risk assessment for these people.

Healthcare professionals and health departments may also request a consultation from the Clinical Immunization Safety Assessment COVIDvax project.

Observation periods following vaccination to monitor for allergic reactions

CDC recommends the following observation periods after COVID-19 vaccination:

• 30 minutes:
  • People with a contraindication to a different type of COVID-19 vaccine (for example, people with a contraindication to mRNA COVID-19 vaccines who receive Janssen vaccine).
  • History of non-severe, immediate (onset within 4 hours) allergic reaction after a previous dose of COVID-19 vaccine.
  • History of an immediate allergic reaction of any severity to non-COVID-19 vaccines or injectable therapies.
  • History of anaphylaxis due to any cause.
• 15 minutes: All other people

Management of anaphylaxis after COVID-19 vaccination

Appropriate medical treatment used to manage immediate allergic reactions must be immediately available in the event an acute anaphylactic reaction occurs following administration of COVID-19 vaccine. Further information on anaphylaxis management can be found in the interim considerations for the management of anaphylaxis following COVID-19 vaccination and laboratory evaluation of people who experience anaphylaxis after vaccination.

Adverse events that occur in a recipient following COVID-19 vaccination should be reported to VAERS. Vaccination providers are required by FDA to report the following that occur after COVID-19 vaccination under BLA or EUA:

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.govexternal icon or by calling 1-800-822-7967.

In addition, CDC has developed a new voluntary, smartphone-based tool, v-safe. This tool uses text messaging and web surveys to provide near real-time health check-ins after patients receive COVID-19 vaccination. Reports to v-safe indicating a medically significant health impact, including pregnancy, are followed up by the CDC/v-safe call center to collect additional information to complete a VAERS report, if appropriate.

In clinical trials of Pfizer-BioNTech and Moderna COVID-19 vaccines in adults, pain at the injection site was the most frequent and severe local reaction. Fatigue, headache, and myalgia were the most common systemic symptoms. Most systemic symptoms were mild to moderate in severity, occurred within the first three days of vaccination, and resolved within 1–2 days of onset. Overall, symptoms were more frequent and severe following the second dose of vaccine and among adolescents and young adults compared with older people.

Available safety and immunogenicity data for Pfizer-BioNTech COVID-19 vaccines in children and adolescents are similar to those seen in young adults. Local and systemic reactions following vaccination are less frequentpdf icon in children ages 5–11 years compared with adolescents and young adults ages 16–25 years.

Syncope (fainting) may occur in association with any injectable vaccine, especially in adolescents. Procedures should be in place to prevent falling injuries and manage syncopal reactions. People should be seated or lying down during vaccination. Vaccine providers, particularly when vaccinating adolescents, should consider observing vaccine recipients for 15 minutes after vaccination to decrease the risk for injury should they faint. If syncope develops, patients should be observed until symptoms resolve.

Unless people have a contraindication to vaccination, they should be encouraged to complete the series to optimize protection against COVID-19 even if they experience local or systemic symptoms following the first dose.

A rare risk for myocarditis and/or pericarditis has been observed following receipt of mRNA COVID-19 vaccines. Cases have occurred predominantly in males ages 12–29 years within the first week after receiving the second dose of an mRNA COVID-19 vaccine. Most patients have been hospitalized for short periods, with most achieving resolution of acute symptoms. Accumulating evidence from multiple sources suggests a higher risk for myocarditis following Moderna compared to Pfizer-BioNTech COVID-19 vaccination.

To date, data suggest the risk for myocarditis and/or pericarditis after mRNA COVID-19 booster doses in young adults appears lower than risk after the primary mRNA COVID-19 vaccine series. Cases of myocarditis among children aged 5–11 years after mRNA COVID-19 vaccine have been rarely reported, and it is not yet known if there is any increased risk for myocarditis or pericarditis after mRNA COVID-19 vaccination in this age group; monitoring is ongoing.

After reviewing available data on the risks and benefits, ACIP and CDC determined that the benefits (e.g., prevention of COVID-19 cases and its severe outcomes) outweigh the risks of myocarditis and pericarditis after receipt of mRNA COVID-19 vaccines for childrenpdf icon, adolescents, and young adults.

People receiving mRNA COVID-19 vaccines, especially males ages 12–29 years, should be made aware of the rare risk of myocarditis and/or pericarditis following receipt of mRNA COVID-19 vaccines and the benefit of COVID-19 vaccination in reducing the risk of severe outcomes from COVID-19, including the possibility of cardiac sequelae. Counseling should include the need to seek care if symptoms of myocarditis or pericarditis, such as chest pain, shortness of breath, or tachycardia develop after vaccination, particularly in the week after vaccination. Extending the interval between the first and second mRNA vaccine dose to 8 weeks might reduce the risk.

Myocarditis or pericarditis after a dose of an mRNA COVID-19 vaccine but before administration of a subsequent dose of COVID-19 vaccine

Development of myocarditis or pericarditis after a dose of an mRNA COVID-19 vaccine is a precaution to a subsequent dose of any COVID-19 vaccine and subsequent doses should generally be avoided.

Until additional safety data are available, experts advise that people who develop myocarditis or pericarditis after a dose of an mRNA COVID-19 vaccine generally should not receive a subsequent dose of any COVID-19 vaccine. If after a risk assessment, the decision is made to receive a subsequent COVID-19 vaccine dose, the person should wait until at least after their episode of myocarditis or pericarditis has resolved (i.e., resolution of symptoms, no evidence of ongoing heart inflammation or sequelae as determined by patient’s clinical team). For men ages 18 years and older who choose to receive a subsequent COVID-19 vaccine, some experts advise the use of Janssen COVID-19 Vaccine be considered instead of mRNA COVID-19 vaccines. These people should be aware of the risk of TTS. Considerations for subsequent vaccination may include:

• The myocarditis or pericarditis was considered unrelated to mRNA COVID-19 vaccination (e.g., due to SARS-CoV-2 or other viruses), especially if the myocarditis or pericarditis diagnosis occurred more than 3 weeks after the most recent dose of COVID-19 vaccine
• Personal risk of severe acute COVID-19 (e.g., age, underlying conditions)
• Level of COVID-19 community transmission and personal risk of infection
• Timing of any immunomodulatory therapies; ACIP’s general best practice guidelines for immunization can be consulted for more information.

History of myocarditis or pericarditis prior to COVID-19 vaccination

• People who have a history of myocarditis or pericarditis unrelated to mRNA COVID-19 vaccination (e.g., due to SARS-CoV-2 or other viruses) may receive any currently FDA-approved or FDA-authorized COVID-19 vaccine after the episode of myocarditis or pericarditis has completely resolved. This includes resolution of symptoms attributed to myocarditis or pericarditis, as well as no evidence of ongoing heart inflammation or sequelae as determined by the person’s clinical team.

Post-vaccination symptoms

In clinical trials of the Janssen COVID-19 Vaccine, pain at the injection site was the most frequently reported local reaction among vaccine recipients; erythema and swelling were reported less frequently. Fatigue and headache were the most commonly reported systemic reactions. Most systemic symptoms were mild to moderate in severity and resolved within 1–2 days. Overall, symptoms were more frequent in people ages 18–59 years compared to people ages 60 years and older.

Thrombosis with thrombocytopenia syndrome

TTS is a rare syndrome that involves acute venous or arterial thrombosis and new onset thrombocytopenia in patients with no recent known exposure to heparin. Although the condition is rare, currently available evidence supports a causal relationship between Janssen COVID-19 Vaccine and TTS. Cases of TTS, including deaths, following administration of the Janssen COVID-19 Vaccine have been reported in males and female, with the highest risk in females ages 30-49 years.

Based on an updated risk-benefit analysis, mRNA COVID-19 vaccines are preferred over the Janssen COVID-19 Vaccine for all vaccine-eligible people. Vaccine providers should start the mRNA COVID-19 vaccine series even if there is uncertainty about how the patient will receive their second dose; setting alone should not be a reason to offer the Janssen COVID-19 Vaccine.

However, the Janssen COVID-19 Vaccine may be offered in some situations as described below:

• When there is a contraindication to mRNA COVID-19 vaccines (e.g., severe allergic reaction after a previous dose or to a component of an mRNA COVID-19 vaccine)
• When a person would otherwise remain unvaccinated for COVID-19 due to limited access to mRNA COVID-19 vaccines
• When a person wants to receive the Janssen COVID-19 Vaccine despite the safety concerns identified

All people who elect to receive a Janssen COVID-19 Vaccine should be informed about the risk and symptoms of TTS that could occur after vaccination (typically within 2 weeks after receipt), the need to seek immediate medical care should such symptoms develop at any time, and the availability of mRNA COVID-19 vaccines instead of the Janssen COVID-19 Vaccine. This guidance applies to the both primary and booster doses of Janssen COVID-19 Vaccine. People should seek medical attention immediately if they develop any of the following symptoms:

• Shortness of breath
• Chest pain
• Leg swelling
• Persistent abdominal pain
• Severe or persistent headaches or blurred vision
• Easy bruising or tiny blood spots under the skin beyond the site of the injection

It is contraindicated to administer Janssen COVID-19 Vaccine to people with a history of TTS following receipt of the Janssen COVID-19 Vaccine or any other adenovirus vector-based COVID-19 vaccines (e.g., AstraZeneca’s COVID-19 Vaccine, which is not authorized or approved in the United States). These people should receive a dose of an mRNA COVID-19 vaccine as a booster at least 2 months following their dose of the Janssen COVID-19 Vaccine and after their clinical condition has stabilized. Prior to booster vaccination, a conversation between the patient and their clinical team, including a hematologist or other specialists, may assist with decisions about using an mRNA COVID-19 vaccine as a booster and the timing of the booster vaccination.

Clinicians should consult the Health Alert Network (HAN) notification and guidanceexternal icon from the American Society of Hematology for information on the diagnosis and treatment of suspected cases of TTS, and report any occurrence of TTS to VAERSexternal icon.

People with a history of thrombosis or risk factors for thrombosis

Although the mechanism of TTS associated with the Janssen COVID-19 Vaccine is unclear, it appears to be similar to another rare immune-mediated syndrome, “spontaneous” heparin-induced thrombocytopenia (HIT).

People with a history of an episode of an immune-mediated syndrome characterized by thrombosis and thrombocytopenia, such as spontaneous or classic HIT, should not receive Janssen COVID-19 Vaccine.  These people should receive a currently FDA-approved or FDA-authorized mRNA COVID-19 vaccine.

Available evidence does not indicate that other thromboembolic conditions (e.g., inherited or acquired thrombophilia, pregnancy, hormonal contraception use) increase the risk of TTS.

Guillain-Barré syndrome (GBS)

Vaccine safety monitoring suggests an elevated risk of GBS after Janssen COVID-19 vaccinationpdf icon  with proportionally more GBS cases observed after Janssen COVID-19 vaccination compared with mRNA COVID-19 vaccination. The highest risk has been observed in males ages 50-64 years, with symptoms of GBS beginning within 42 days after Janssen COVID-19 vaccination.

People should seek medical attention immediately if they develop any of the following symptoms after receiving Janssen COVID-19 Vaccine:

• Weakness or tingling sensations, especially in the legs or arms, that is worsening and spreading to other parts of the body
• Difficulty walking
• Difficulty with facial movements, including speaking, chewing, or swallowing
• Double vision or inability to move eyes
• Difficulty with bladder control or bowel function

Development of GBS after receipt of Janssen COVID-19 Vaccine is a precaution for receiving subsequent dose(s) of the Janssen COVID-19 Vaccine. People who develop GBS within 6 weeks after receipt of Janssen COVID-19 Vaccine should not receive another dose of Janssen COVID-19 Vaccine. An mRNA COVID-19 vaccine should be used for any subsequent doses. Providers should also strongly consider using an mRNA COVID-19 vaccine for subsequent doses in people who had GBS onset beyond 6 weeks after receipt of Janssen COVID-19 Vaccine. Any occurrence of GBS following COVID-19 vaccination should be reported to VAERS.

People with a known or potential COVID-19 exposure

COVID-19 vaccines are not recommended for post-exposure prophylaxis to prevent SARS-CoV-2 infection. Unvaccinated people who were close contacts of a person with SARS-CoV-2 infection should typically not seek vaccination until quarantine has ended; this is to reduce the risk of transmission to others (e.g., healthcare personnel, other clinic patients), because vaccination is not expected to prevent SARS-CoV-2 infection that could occur after the exposure for which the person is in quarantine, and to avoid confusion between vaccination side effects and symptoms of COVID-19.

In certain circumstances, to avoid missed opportunities for vaccination, vaccination during quarantine could be considered during outreach and contact tracing activities or at the time of post-exposure SARS-CoV-2 testing. Examples might include when people 1) are likely to have repeated SARS-CoV-2 exposures because they are unable to effectively quarantine (e.g., residing in a congregate or crowded setting or during outbreaks in their community), or, 2) will have limited access to vaccination after their quarantine period has ended, or, 3) are unlikely to otherwise seek vaccination after their quarantine period has ended. In such situations, the person recommended for quarantine can receive vaccination as long as 1) they do not have symptoms consistent with COVID-19 or current SARS-CoV-2 infection, and, 2) appropriate infection prevention and control procedures are employed during vaccination.

However, they should also be informed that vaccination may not prevent SARS-CoV-2 infection until 2 weeks after the primary series is completed, i.e., will not prevent them from getting COVID-19 from the current exposure but should help protect them from infection after future exposures. In addition, SARS-CoV-2 viral testing may be necessary to differentiate between common post-vaccination symptoms and symptoms of SARS-CoV-2 infection:

• People who develop signs and symptoms associated with COVID-19 (e.g., cough, shortness of breath, runny nose, sore throat, loss of taste or smell) should isolate and be evaluated for SARS-CoV-2 infection as soon as possible.
• People who develop signs and symptoms that could be from either COVID-19 vaccination or SARS-CoV-2 infection (e.g., fever, fatigue, headache, myalgia) without typical COVID-19 symptoms described above, and are clinically stable, should isolate and, if symptoms do not improve by two days post-vaccination, be evaluated for SARS-CoV-2 infection.

People with prior or current SARS-CoV-2 infection

COVID-19 vaccination is recommended for everyone ages 5 years and older, regardless of a history of symptomatic or asymptomatic SARS-CoV-2 infection. This includes people with prolonged post-COVID-19 symptoms and applies to primary series and booster doses. This recommendation also applies to people who experience SARS-CoV-2 infection before or after receiving any COVID-19 dose.

People with known current SARS-CoV-2 infection should defer any COVID-19 vaccination, including booster vaccination, at least until recovery from the acute illness (if symptoms were present) and criteria to discontinue isolation have been met. Current evidence demonstrates a robust immune response to vaccination after infection, but information is lacking about whether and how the amount of time since infection affects the immune response to vaccination.

Growing epidemiologic evidence from adults and adolescents indicates that vaccination following infection further increases protection from subsequent infection, including in the setting of increased circulation of more infectious variants. Viral testing to assess for acute SARS-CoV-2 infection or serologic testing to assess for prior infection is not recommended for the purpose of vaccine decision-making.

People with a history of multisystem inflammatory syndrome in children (MIS-C) or adults (MIS-A)

Multisystem inflammatory syndrome in children (MIS-C) is a rare but severe condition in children and adolescents infected with SARS-CoV-2. Multisystem inflammatory syndrome in adults (MIS-A) appears to be even rarer and is less well characterized than in children. The mechanisms of MIS-C and MIS-A are not well understood but include a dysregulated immune response to SARS-CoV-2 infection. The risk of recurrence of the same dysregulated immune response following reinfection with SARS-CoV-2 among people with a history of MIS-C or MIS-A is unknown. It is also unknown if some people with a history of MIS-C or MIS-A may be at risk for an MIS-like illness following vaccination with COVID-19 vaccine.

Children with MIS-C have high antibody titers to SARS-CoV-2external icon, however, it is unknown if this correlates with protection against reinfection and for how long the protection might last.

A conversation between the patient, their guardian(s), and their clinical team or a specialist (e.g., specialist in infectious diseases, rheumatology, or cardiology) is strongly encouraged to assist with decisions about the use of COVID-19 vaccines in people who have had MIS-C or MIS-A from SARS-CoV-2 infection who have not yet received COVID-19 vaccine.

Experts consider the benefits of COVID-19 vaccination for children and adolescents (i.e., a reduced risk of severe disease including potential recurrence of MIS-C after reinfection) to outweigh a theoretical risk of an MIS-like illness or the risk of myocarditis following COVID-19 vaccination for people who meet all of the following criteria:

1. Clinical recovery has been achieved, including return to normal cardiac function;
2. It has been ≥90 days since their diagnosis of MIS-C;
3. They are in an area of high or substantial community transmission of SARS-CoV-2 or otherwise have an increased risk for SARS-CoV-2 exposure and transmission; and
4. Onset of MIS-C occurred before any COVID-19 vaccination.

COVID-19 vaccination may also be considered for people with a history of MIS-C from SARS-CoV-2 infection who have not yet received COVID-19 vaccine and who do not meet all the above criteria or for people with a history of MIS-A from SARS-CoV-2 infection who have not yet received COVID-19 vaccine. Experts view clinical recovery, including return to normal cardiac function, as an important factor when considering COVID-19 vaccination. Additional factors when considering individual benefits and risks may include:

1. An increased personal risk of severe COVID-19 (e.g., age, underlying conditions)
2. Timing of immunomodulatory therapies (ACIP’s general best practice guidelines for immunization can be consulted for more information)

People diagnosed with MIS-C or MIS-A after COVID-19 vaccination

In the rare instance a person develops MIS-C, MIS-A, or a similar clinical illness after receipt of a COVID-19 vaccine, referral to a specialist in infectious diseases, rheumatology, and/or cardiology should be considered. These people should be assessed for laboratory evidence of current or prior SARS-CoV-2 infection. Healthcare and public health professionals should also consider requesting a consultation from the Clinical Immunization Safety Assessment COVIDvax project. An illness consistent with MIS-C or MIS-A occurring in people who received any COVID-19 vaccine should be reported to VAERSexternal icon.

People who received passive antibody products

People who previously received antibody products (anti-SARS-CoV-2 monoclonal antibodies or convalescent plasma) as part of COVID-19 treatment, post-exposure prophylaxis, or pre-exposure prophylaxis can be vaccinated at any time; COVID-19 vaccination does not need to be delayed following receipt of monoclonal antibodies or convalescent plasma. Although some reduction in vaccine-induced antibody titersexternal icon was observed in people who previously received antibody products, the clinical significance of this reduction is unknown, and the balance of benefits vs. risks favors proceeding with vaccination even considering the possibility of diminished vaccine effectiveness in this situation.

However, in people who previously received a COVID-19 vaccine, administration of tixagevimab/cilgavimab (EVUSHELD™) for pre-exposure prophylaxis should be deferred for at least two weeks after vaccination, per the product EUAexternal icon.

COVID-19 vaccination is recommended for people who are pregnant, lactating, trying to get pregnant now, or who might become pregnant in the future.

Staying up to date with COVID-19 vaccinations is recommended for people who are pregnant. Although the overall risks are low, pregnant and recently pregnant people (for at least 42 days following the end of pregnancy) with COVID-19 are at increased risk for severe illness when compared with non-pregnant people. Additionally, pregnancies affected by COVID-19 are at increased risk for preterm birth and stillbirths, and might be at increased risk for other complications.

A growing body of evidence on the safety and effectiveness of COVID-19 vaccination indicates that the benefits of vaccination outweigh any known or potential risks of COVID-19 vaccination during pregnancy.

A conversation between the patient and their clinical team may assist with decisions about the use of a COVID-19 vaccine; however, approval by a healthcare professional is not required before vaccination. Data on uptake of COVID-19 vaccination among pregnant people can be found on CDC’s COVID Data Tracker.

Side effects can occur after COVID-19 vaccination in pregnant people, similar to those among non-pregnant people. Acetaminophen can be offered as an option for pregnant people experiencing fever (fever has been associated with adverse pregnancy outcomes) or other post-vaccination symptoms.

Lactation

COVID-19 vaccination is recommended for all lactating people. Because clinical trials of COVID-19 vaccines did not include people who were lactating, there are limited data on the safety of COVID-19 vaccines in lactating people or the effects of COVID-19 vaccines on the breastfed infant, milk production, and milk secretion. Recent reports have shown that the antibodies developed from mRNA COVID-19 vaccination received both during and after pregnancy were present in breastmilk samples. More data are needed to determine if these antibodies convey protection against SARS-CoV-2 infection for neonates and infants.

Fertility

There is currently no evidence that any vaccines, including COVID-19 vaccines, cause fertility problems. 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 COVID-19 vaccination.

More information on myocarditis and COVID-19 vaccination can be found here.

People with autoimmune conditions

People with autoimmune conditions may receive any currently FDA-approved or FDA-authorized COVID-19 vaccine but, as with the general population, mRNA vaccines are preferred over the Janssen COVID-19 Vaccine. If people with these conditions are immunocompromised because of medications such as high-dose corticosteroids or biologic agents, they should consult Guidance for COVID-19 vaccination for people who are moderately or severely immunocompromised.

People with a history of Bell’s palsy

Rare cases of Bell’s palsy (acute peripheral facial nerve palsy) were reported following vaccination of participants in the mRNA COVID-19 vaccine clinical trials, but FDA was not able to determine whether these cases were causally related to vaccination. People with a history of Bell’s palsy may receive any currently FDA-approved or FDA-authorized COVID-19 vaccine.

People with a history of Guillain-Barré syndrome

Guillain-Barré syndrome (GBS) is a neurological disorder in which the body’s immune system damages nerve cells, causing muscle weakness and sometimes paralysis. For people with a history of GBS, as with the general population, an mRNA COVID-19 vaccine is preferred over Janssen COVID-19. No increased risk of GBS has been identified with mRNA COVID-19 vaccines.

An elevated risk of GBS after receipt of the Janssen COVID-19 vaccine has been observed. A history of GBS is a precaution for receipt of the Janssen COVID-19 vaccine. For people with a history of GBS after Janssen COVID-19 Vaccine, see Considerations for Janssen COVID-19 Vaccine.

People with a history of dermal filler use

Infrequently, people who have received dermal fillers might experience swelling at or near the site of filler injection (usually face or lips) following administration of a dose of an mRNA COVID-19 vaccine. The swelling is temporary and resolves with medical treatment, including corticosteroid therapy.  People should be advised to contact their healthcare professional for evaluation if they experience swelling at or near a dermal filler site following vaccination.

People receiving antiviral therapy

Administration of an antiviral drug at any interval before or after vaccination with any of the currently FDA-approved or FDA-authorized COVID-19 vaccines is unlikely to impair development of a protective antibody response.

People undergoing testing for tuberculosis infection

COVID-19 vaccination should not be delayed because of testing for tuberculosis (TB) infection. Testing for TB infection with one of the immune-based methods, either the tuberculin skin test (TST) or an interferon-gamma release assay (IGRA), can be done before, after, or during the same encounter as COVID-19 vaccination.

People undergoing testing for syphilis

FDA has reportedexternal icon that falsely reactive Rapid Plasma Reagin (RPR; non-treponemal) test resultsexternal icon can occur with certain RPR tests for at least five months following COVID-19 vaccination in some people. Treponemal testing for syphilis such as Treponema pallidum particle agglutination (TP-PA) and treponemal immunoassays do not appear to be impacted by this issue.

1. COMIRNATY is the proprietary name for the product licensed under the Biologics License Application (BLA). The Pfizer-BioNTech COVID-19 Vaccine has been available since December 10, 2020 under an Emergency Use Authorization (EUA). The originally-authorized Pfizer-BioNTech COVID-19 Vaccine has the same formulation as COMIRNATY, and vials of the BLA-compliant vaccine may bear the name “Pfizer-BioNTech COVID-19 Vaccine.” The FDA-approved COMIRNATY (COVID-19 Vaccine, mRNA) and the emergency use authorized formulations of Pfizer-BioNTech COVID-19 Vaccine for people ages 12 years and older (purple cap/label and gray cap/label), when prepared according to their respective instructions for use, can be used interchangeably.external icon The Pfizer-BioNTech COVID-19 Vaccine supplied with an orange cap and a label with an orange border is authorized for use only in children ages 5-11 years. It is NOT interchangeable with COMIRNATY and Pfizer-BioNTech COVID-19 Vaccine for ages 12 years and older (purple cap/label and gray cap/label).
2. SPIKEVAX is the proprietary name for the product licensed under the Biologics License Application (BLA). The Moderna COVID-19 Vaccine has been available since December 18, 2020 under an Emergency Use Authorization (EUA). The originally-authorized Moderna COVID-19 Vaccine has the same formulation as SPIKEVAX. The FDA-approved SPIKEVAX (COVID-19 Vaccine, mRNA) and the emergency use authorized formulations of Moderna COVID-19 Vaccine for people ages 18 years and older, when prepared according to their respective instructions for use, can be used interchangeablyexternal icon.
3. For intervals of 3 months or less, 28 days (4 weeks) is a “month.” For intervals of 4 months or longer, a month is a “calendar month”; e.g., a person who completed the second dose of a 2-dose primary series on September 1, 2021, can receive a booster dose as soon as February 1, 2022 (5 months after completion of the primary series).
4. The Society of Breast Imaging has developed Recommendations for the Management of Axillary Adenopathy in Patients with Recent COVID-19 Vaccinationpdf iconexternal icon which includes considerations for patients and healthcare professionals in scheduling screening exams in relation to the administration of a COVID-19 vaccine.

The recommendations for people vaccinated outside of the United States depend on the vaccine(s) received for the primary series, whether the primary series was completed, and whether a booster dose was received. People who initiated vaccination outside of the United States are considered to be up to date with their COVID-19 vaccines when they have completed the recommended actions described below.

For people who received all FDA-approved or -authorized COVID-19 vaccines, Pfizer-BioNTech COVID-19 Vaccine can be used in people ages 5 years and older and Moderna COVID-19 Vaccine can be used in people 18 years and older to complete vaccination.

For people who received at least one COVID-19 vaccine that was not FDA-approved or -authorized, Pfizer-BioNTech COVID-19 Vaccine can be used in people ages 12 years and older and Moderna COVID-19 Vaccine can be used in people ages 18 years and older to complete vaccination.*

Table A: People who received COVID-19 vaccine outside the United States

Table Ai: Received a COVID-19 vaccine that is FDA-approved or FDA-authorized

Table Aii: Received a COVID-19 vaccine listed for emergency use by WHO but not approved or authorized by FDA^*†

Table Aiii: Received a heterologous primary series composed of doses of a COVID-19 vaccine listed for emergency use by WHO, at least one of which is not FDA-approved or authorized^*†

Table Aiv: Received all or some of the recommended doses of COVID-19 vaccines that are NOT FDA-authorized, FDA-approved, or among those listed for emergency use by WHO

*The EUI provides a legal framework for heterologous use of mRNA COVID-19 vaccines (i.e., Pfizer-BioNTech and Moderna) in people who received a non-FDA authorized or approved COVID-19 vaccine outside of US.

^†COVID-19 vaccines that are listed for emergency use by WHOpdf iconexternal icon that are not FDA-authorized or FDA-approved have not been evaluated for efficacy or safety by CDC or ACIP.

Participants in clinical trials within or outside the United States who received all the recommended primary series doses of a WHO-EUL COVID-19 vaccinepdf iconexternal icon (i.e., not placebo) that is not FDA-approved or FDA-authorized are considered fully vaccinated. In addition, people who received a vaccine that is not listed for emergency use by WHO but for which a U.S. data and safety monitoring board or equivalent has independently confirmed efficacy are considered fully vaccinated; at this time, only the Moderna COVID-19 Vaccine in children ages 6–17 years and the Medicago COVID-19 Vaccine in people 18 years of age and older meets these criteria.

• Moderately or severely immunocompromised clinical trial participants should receive an additional dose of Pfizer-BioNTech COVID-19 Vaccine (ages 12 years and older) or Moderna COVID-19 Vaccine (ages 18 years and older) 28 days after receiving the second vaccine dose of a primary series as detailed in the Considerations for COVID-19 vaccination in moderately or severely immunocompromised people, unless they have received or plan to receive an additional or booster dose through a clinical trial.
• Clinical trial participants (including moderately or severely immunocompromised people who received a 3-dose primary series) should receive a single booster dose of Pfizer-BioNTech COVID-19 Vaccine (ages 12 years and older) or Moderna COVID-19 Vaccine (ages 18 years and older), unless they have received or plan to receive a booster dose through a clinical trial.

If clinical trial participants have questions about whether they should receive an additional and/or booster dose outside of the clinical trial, they should consult with their healthcare provider. Clinical trial participants who did not receive all the recommended doses, or who received other vaccines not listed above, should consult with their healthcare provider to determine if they should receive an FDA-approved or FDA-authorized COVID-19 vaccine series.

A vaccine administration error is any preventable event that may cause or lead to inappropriate use of vaccine or patient harm.

• Inform the recipient of the vaccine administration error.
• Consult with the state immunization program and/or immunization information system (IIS) to determine how the dose should be entered into the IIS, both as an administered dose and to account for inventory.
• Report the error to the Vaccine Adverse Event Reporting System (VAERS), unless otherwise indicated in the table. Providers are required to report all COVID-19 vaccine administration errors—even those not associated with an adverse event—to VAERS. To file an electronic report, please see the VAERS websiteexternal icon.
• Determine how the error occurred and implement strategies to prevent it from happening again. A discussion on strategies to prevent errors can be found in the “Vaccine Administration” chapter of Epidemiology and Prevention of Vaccine-Preventable Diseases (Pink Book). Additional resources can be found on CDC’s vaccine administration web page, including a job aid for preventing errors.
• Follow the revaccination guidance in the table below, using an age-appropriate COVID-19 vaccine and formulation. Then continue with the recommended schedule of subsequent dose(s) unless otherwise noted (see footnotes to this Appendix).

• • For doses recommended to be repeated, some experts suggest further delaying the repeated dose for 8 weeks after the invalid dose based on the potential for increased reactogenicity and the rare risk of myocarditis from mRNA COVID-19 vaccine, particularly in groups at increased risk for myocarditis (e.g., 12-29 year old males). Individual risk for COVID-19 and the likelihood for an adverse event following COVID-19 vaccination should be taken into consideration when recommending a longer interval.

The recommendations in the table below apply to all FDA-approved or FDA-authorized COVID-19 vaccines and all doses (i.e., primary series and booster doses), unless otherwise stated.

Table C. Interim recommendations for COVID-19 vaccine administration errors and deviations

^*Do not administer the second dose until the person becomes eligible to receive vaccination (either by reaching the authorized age or if the authorization is extended to include additional age groups), even if this results in the second dose being administered after the recommended interval between doses.

^†If the administration error resulted in a higher-than-authorized vaccine dose, in general a subsequent dose may still be administered at the recommended interval. However, if local or systemic side effects following vaccination are clinically concerning (outside of the expected side effect profile), lead to serious adverse reactions, or are ongoing at the time of the subsequent dose, this dose might be delayed, but this decision should be assessed on a case-by-case basis.

^‡ People who will turn from age 11 years to 12 years between their first and second dose in the primary regimen may receive, either: (1) the Pfizer-BioNTech COVID-19 Vaccine formulation authorized for use in people ages 5 through 11 years (each 0.2 mL dose containing 10 µg) (orange cap); or (2) the Pfizer-BioNTech COVID-19 Vaccine formulation authorized for use in people ages 12 years and older (each 0.3 mL dose containing 30 µg) (purple or gray cap). This dosing is in accordance with the FDA EUA and if such dosing occurred, this is not considered an error and VAERS reporting is not indicated.

^§Some experts suggest further delaying the repeat dose for 8 weeks after the invalid dose based on the potential for increased reactogenicity and the rare risk of myocarditis from mRNA COVID-19 vaccine, particularly in groups at increased risk for myocarditis (e.g., 12-29 year old males). Individual risk for COVID-19 and the likelihood for an adverse event following vaccination should be taken into consideration when recommending a longer interval.

^¶For the purpose of the public health definition of fully vaccinated, doses administered with an interval error prior to October 25, 2021 do not need to be repeated.

^#Vaccine administered up to 4 days before the minimum interval may be counted and do not need to be repeated.

Note: This table is specific to allergy-related contraindications and precautions and is not inclusive of all COVID-19 vaccine contraindications and precautions.

^* See Appendix F for a list of ingredients. People with a contraindication to one of the mRNA COVID-19 vaccines should not receive doses of either of the mRNA vaccines (Pfizer-BioNTech or Moderna). However, some of these people may be able to receive Janssen COVID-19 Vaccine after a detailed risk assessment and possibly allergy testing (see footnote ¶ below).

^†Severe allergic reactions include:

• Possible anaphylaxis, a progressive life-threatening reaction that typically includes urticaria but also with other symptoms such as wheezing, difficulty breathing, or low blood pressure
• Any angioedema affecting the airway (i.e., tongue, uvula, or larynx)
• Diffuse rash which also involves mucosal surfaces (e.g., Stevens-Johnson Syndrome)

Non-severe allergic reactions may include:

• Urticaria (hives) beyond the injection site
• Angioedema (visible swelling) involving lips, facial skin, or skin in other locations. NOTE: Any angioedema affecting the airway (i.e., tongue, uvula, or larynx) would NOT be in this category and is considered a severe allergic reaction

^‡Immediate allergic reaction to a vaccine or injectable therapy is defined as any hypersensitivity-related signs or symptoms consistent with urticaria, angioedema, respiratory distress (e.g., wheezing, stridor), or anaphylaxis that occur within four hours following administration.

People with a history of an immediate allergic reaction to a non-COVID-19 vaccine or injectable therapy that contains multiple components, one or more of which is a component of a COVID-19 vaccine, but it is unknown which component elicited the allergic reaction, have a precaution to vaccination with that COVID-19 vaccine. These people may benefit from consultation with an allergist-immunologist who can perform a more detailed risk assessment for COVID-19 vaccine receipt and possibly allergy testing.

^¶ Polyethylene glycol (PEG) is an ingredient in both mRNA COVID-19 vaccines, and polysorbate 80 is an ingredient in Janssen COVID-19 Vaccine. PEG and polysorbate are structurally related, and cross-reactive hypersensitivity between these compounds may occur. People with a contraindication to mRNA COVID-19 vaccines (including due to a known allergy to PEG) have a precaution to Janssen COVID-19 Vaccine. Among people who received a first mRNA COVID-19 dose but for whom the second dose is contraindicated, consideration may be given to vaccination with Janssen COVID-19 Vaccine (administered at least 28 days after the mRNA COVID-19 dose). People with a contraindication to Janssen COVID-19 Vaccine (including due to a known allergy to polysorbate) have a precaution to mRNA COVID-19 vaccines. For people with these precautions, referral to an allergist-immunologist should be considered. Healthcare professionals and health departments may also request a consultation from the Clinical Immunization Safety Assessment COVIDvax project. In patients with these precautions, vaccination should only be undertaken in an appropriate setting under the supervision of a healthcare professional experienced in the management of severe allergic reactions.

^# For people with a history of an immediate, non-severe allergic reaction after an mRNA COVID-19 vaccine, vaccination with a subsequent dose of either of the mRNA COVID-19 vaccines should only be undertaken in an appropriate setting under the supervision of a health care provider experienced in the management of severe allergic reactions. Similarly, for people with a history of an immediate, non-severe allergic reaction after Janssen COVID-19 Vaccine, vaccination with a subsequent dose of Janssen vaccine should only be undertaken under the supervision of a health care provider experienced in the management of severe allergic reactions. Administering the other vaccine type is another option; this can be done with a 30-minute observation period in a usual COVID-19 vaccination setting.

The following is a list of ingredients for the Pfizer-BioNTechexternal icon, Modernaexternal icon, and Janssenexternal icon COVID-19 Vaccines reported in the prescribing information for each vaccine.*

* None of the vaccines contain eggs, gelatin, latex, or preservatives. All COVID-19 vaccines are free from metals such as iron, nickel, cobalt, lithium, rare earth alloys or any manufactured products such as microelectronics, electrodes, carbon nanotubes, or nanowire semiconductors.
Note: Both the Pfizer-BioNTech and Moderna COVID-19 vaccines contain polyethylene glycol (PEG). PEG is a primary ingredient in osmotic laxatives and oral bowel preparations for colonoscopy procedures, an inactive ingredient or excipient in many medications, and is used in a process called “pegylation” to improve the therapeutic activity of some medications (including certain chemotherapeutics). Additionally, cross-reactive hypersensitivity between PEG and polysorbates (included as an excipient in some vaccines and other therapeutic agents) can occur. Information on active or inactive ingredients for vaccines and medications can be found in the package insert. CDC’s vaccine excipient summarypdf icon and the National Institutes of Health DailyMed databaseexternal icon can also be used as a resource.