ACEP COVID-19 Field Guide

Table of Contents

Vaccinations and Prevention


Author: Sandra M. Schneider, MD, FACEP – University of Pittsburgh and the American College of Emergency Physicians

Prevention and prophylaxis of COVID-19 infection

  • Since 2023, Omicron and its variants have become the dominant strains. These strains are resistant to current monoclonal antibodies. The COVID-19 NIH guidelines no longer recommend using any anti-SARS-CoV-2 monoclonal antibodies (bamlanivimab plus etesevimab, casirivimab plus imdevimab) as pre- or post-exposure prophylaxis.
  • The COVID-19 NIH guidelines do not recommend using any drugs for SARS-CoV-2 pre- or post-exposure prophylaxis, except in a clinical trial (AIII).
  • The COVID-19 NIH guidelines recommend COVID-19 vaccination for everyone who is eligible according to the Advisory Committee on Immunization Practices (ACIP).


Vaccine recommendations change. For the most accurate and up-to-date information, see the CDC’s “Use of COVID-19 Vaccines in the United States,” “Stay Up to Date With COVID-19 Vaccines," and "Urgent Need to Increase Immunization Coverage for Influenza, COVID-19, and RSV.”

Resources for addressing vaccine hesitancy

Vaccine overview

The Moderna and Pfizer-BioNTech vaccines and boosters are messenger RNA (mRNA) vaccines directed against the spike protein from SARS-CoV-2. 

  • SARS-CoV-2 is an RNA virus that has a very high mutation rate.1
  • Its spike protein facilitates entry into a cell. Like other areas of the virus, the spike protein can also mutate, which can make vaccines less effective.
  • mRNA vaccines do not contain a live virus.
  • mRNA vaccines do not enter the nucleus of a cell or affect a person’s DNA.

The Janssen COVID-19 vaccine is no longer available in the United States. The adjuvanted Novavax COVID-19 vaccine contains the SARS-CoV-2 spike protein and Matrix-M adjuvant.

For more vaccine resources, see the CDC’s “Prevaccination Checklist for COVID-19 Vaccines,” “Updated (2023-2024 Formula) COVID-19 Vaccine,” and the vaccine glossary.

Considerations for COVID-19 vaccination

At the time of publication, the CDC recommends COVID-19 vaccination for all people ages 6 months and older, including people who are pregnant, breastfeeding, trying to get pregnant, or may become pregnant.

  • People with prior or current SARS-CoV-2 infection
    • Vaccination during a symptomatic or asymptomatic COVID-19 infection is not recommended, but a COVID-19 vaccine after recovery provides added protection. You may consider delaying vaccination by 3 months from when symptoms started or, if asymptomatic, from when a positive test was done.
  • People with a history of multisystem inflammatory syndrome (MIS)
  • People with moderate and severe immunocompromising conditions. Vaccination against COVID-19 is generally recommended for people with moderate and severe immunocompromising conditions to lessen the likelihood of severe illness; however, some of these conditions may not respond to vaccination. Moderate and severe immunocompromising conditions can include:
    • Active treatment for solid tumor and hematologic malignancies;
    • Hematologic malignancies associated with poor responses to COVID-19 vaccines regardless of current treatment status (eg, chronic lymphocytic leukemia, non-Hodgkin lymphoma, multiple myeloma, acute leukemia);
    • Receipt of solid-organ transplant or an islet transplant and taking immunosuppressive therapy;
    • Receipt of chimeric antigen receptor (CAR)-T-cell therapy or hematopoietic cell transplant (HCT) (within 2 years of transplantation or taking immunosuppressive therapy);
    • Moderate or severe primary immunodeficiency (eg, common variable immunodeficiency disease, severe combined immunodeficiency, DiGeorge syndrome, Wiskott-Aldrich syndrome); and
    • Advanced HIV infection (people with HIV and CD4 cell counts less than 200/mm3, a history of an AIDS-defining illness without immune reconstitution, or clinical manifestations of symptomatic HIV) or untreated HIV infection.
  • People who are pregnant or breastfeeding
    • COVID-19 during pregnancy can increase the likelihood of severe illness and pregnancy complications that affect the unborn child.
    • Immunity to COVID-19 may be passed between a mother and newborn through breast milk.

For more information on vaccination during pregnancy, see the American College of Obstetricians and Gynecologists’ “COVID-19 Vaccination Considerations for Obstetric-Gynecologic Care.” For more information on COVID-19 and breastfeeding, see “COVID-19 Vaccines.”

Complications from COVID-19 vaccines

  • Anaphylaxis
    • Rare
    • Anaphylaxis has occurred in approximately two to five people per one million vaccinated in the United States.
    • If anaphylaxis occurs, the health care professionals who administer the vaccine can effectively and immediately treat the reaction.

Read the CDC’s “Interim Considerations: Preparing for the Potential Management of Anaphylaxis After COVID-19 Vaccination” for more information.

  • Thrombosis with thrombocytopenia syndrome (TTS) and Guillain-Barré syndrome
    • Both were reported vaccine adverse events after the Janssen COVID-19 vaccination, which is now no longer available in the United States.
  • Myocarditis and pericarditis after COVID-19 vaccination
    • Rare
    • Most cases have been reported after mRNA COVID-19 vaccination (Pfizer-BioNTech or Moderna vaccines), particularly in male adolescents and young adults.
    • Re-vaccination is generally not recommended for people with suspected vaccine-induced myocarditis or pericarditis.

For more information, see the CDC’s “Clinical Considerations: Myocarditis and Pericarditis After Receipt of COVID-19 Vaccines Among Adolescents and Young Adults.”

Vaccine adverse events, including serious, life-threatening events and deaths, should be reported to the Vaccine Adverse Events Reporting System (VAERS).

Post-vaccine considerations

Systemic signs and symptoms, such as fever, fatigue, headache, chills, myalgia, and arthralgia, can occur following COVID-19 vaccination. Preliminary data from mRNA COVID-19 vaccine trials indicate that most systemic post-vaccination signs and symptoms:

  • Are mild to moderate in severity;
  • Occur within the first 3 days of vaccination;
  • Resolve within 1 to 2 days of onset; or
  • Are more frequent and severe following the second dose and in people who are younger than 55 years.

Cough, shortness of breath, rhinorrhea, sore throat, or loss of taste or smell are not consistent with post-vaccination symptoms and, instead, may be symptoms of SARS-CoV-2 or another infection. Lymphadenopathy can occur after vaccination. Women who get mammograms should wait 2 to 3 months after vaccination before their next mammogram to avoid a false-positive finding.

For more information on what to expect after vaccination, see the CDC’s “Getting Your COVID-19 Vaccine.”

COVID-19 emergency department vaccination programs

Authors: Thomas Benzoni, DO, EM, AOBEM, FACEP – Des Moines University Medicine and Health Sciences; Herbie Duber, MD, MPH, FACEP – University of Washington; Daniel Martin, MD – The Ohio State University Wexner Medical Center; Phillip Moschella, MD, PhD – Prisma Health/University of South Carolina School of Medicine Greenville; and Michael Waxman, MD, MPH, FACEP – Albany Medical Center.

Although treatments and preventative measures showed promise in curbing the morbidity associated with COVID-19, the pandemic called for the quick development of safe and effective vaccines. COVID-19 vaccines were shown to increase neutralizing antibodies, prevent disease, and have a high safety profile.

Emergency departments in general are a safety net and focal point in public health initiatives, offering services such as screening and brief intervention for drug and alcohol use, HIV screening, and tetanus and influenza immunizations. Emergency department patients are increasingly and disproportionately the underserved, uninsured, and minority of society who are less likely to be vaccinated and have adequate access to preventative and primary care. This population has also been disproportionately affected by COVID-19 infections, experiencing more morbidity and mortality. Emergency departments play a critical role in public health during pandemics like COVID-19 because they can offer vaccination programs to these underserved people.

Emergency department–based preventative interventions are varied and site specific. Each site makes its own decisions on whether and whom to vaccinate. Vaccination decisions are based on local resources, local demand for vaccines, and the ability to refer patients for second rounds of vaccination.

This section discusses how to develop COVID-19 or any other vaccination program, including selecting vaccine candidates, emergency department requirements, and best practices for vaccine administration and documentation. Four caveats must be kept in mind when considering these suggestions for an emergency department vaccination program:

  • First, an emergency department is not intended to be a primary vaccination site (ie, patients go to the emergency department specifically for a vaccine);
  • Second, for vaccines that require more than one round, patients who received their first vaccine in the emergency department should receive any subsequent rounds at a site outside of the emergency department;
  • Third, because an emergency department’s vaccination efforts often significantly overlap with their larger hospital system’s vaccination program, the vaccination program in the emergency department should be consistent with the hospital’s larger vaccination program; and
  • Lastly, vaccinating with any new vaccines is a dynamic process. Emergency departments should regularly check with their local, state, and national recommendations to learn of any changes or updates to vaccination recommendations as more data become available.

Who should receive new vaccines at emergency departments?

Emergency departments with vaccine programs must establish their goals and explain how they can augment local vaccination programs to help the population they serve. Patients who are most in need of vaccination in the emergency department likely have limited access to vaccinations in more traditional settings and include immigrants, people with limited English proficiency, low-income populations, communities of color, and other underserved populations. The overall priority is to offer vaccination to all eligible patients, especially those from vulnerable populations. Early steps to plan for such a targeted program include:

  • Identifying the other vaccination programs available in the area, the populations they serve, and their current level of efficiency;
  • Being aware of the overall current patient populations served in the emergency department;
  • Recognizing priority populations, especially the vulnerable and underserved populations; and
  • Prioritizing those unique patients who are seen in the emergency department but are not served by other programs in the local area.

Where in the emergency department should vaccines be administered?

COVID-19 vaccination programs are likely to vary between emergency departments. Three examples of places where an emergency department may perform their COVID-19 screens and vaccinations are (1) in triage, (2) during treatment, and (3) within discharge flow. Another model includes referral of appropriate emergency department patients to an on-site vaccination clinic or to an off-site vaccine distribution area.

What is required when starting an emergency department vaccination program?

Instituting a vaccination program in the emergency department requires partnership with key stakeholders at departmental, institutional, and regional levels.

Departmental engagement and partnership

  • Emergency department nursing. Unless the institution plans to hire additional external staff to administer vaccines in the emergency department, the emergency department’s nursing and pharmacy staff will likely be the ones doing it. Nursing leadership needs to be aware of issues that could affect patient flow and the vaccination process. Additionally, nursing leadership will need to facilitate educating their nursing staff about the vaccination processes and the risks and benefits of vaccination for patients.
  • Emergency department medical director and physician staff. Ensuring buy-in from physician leadership and those on shift is critical to facilitating successful emergency department vaccination programs.

Institutional engagement and partnership

  • Pharmacy. Pharmacy consultation and partnership are necessary for issues like vaccine storage, reconstitution, administration, and reporting. Pharmacy staff can also help with key aspects of nursing education. In institutions with emergency department pharmacists, consider how they can support the vaccination program. In some jurisdictions, pharmacy staff can directly administer vaccinations.
  • Hospital leadership. Buy-in from hospital leadership is necessary to ensure the emergency department has the vaccine supply and receives enough external support. Focusing on the health mission and vulnerable populations who seek care only in the emergency department can facilitate these discussions. Furthermore, hospital leadership can facilitate discussions with primary care groups to support non–emergency department locations for subsequent doses of vaccine series.

Regional engagement and partnership

  • Department of public health (DPH). Working with the local DPH can ensure clear messaging about the role of the emergency department in local vaccination efforts (ie, the emergency department should not be the primary location for vaccination but rather part of a regional effort).
  • Regional emergency departments. Coordinating efforts between emergency departments to align health missions and opportunities for cross learning of best practices will facilitate regional emergency department vaccination efforts.
  • ACEP state chapters. Leadership should be aligned at the state level to support emergency departments in their vaccination efforts and to ensure proper messaging.
  • Community-based organizations (CBOs). Partnership with CBOs is helpful to create opportunities for administering subsequent vaccine doses of vaccine series in other locations. CBOs are highly knowledgeable of the local community, including opportunities for primary and urgent care groups that focus on low-income and underserved communities.

Other important considerations when pursuing an emergency department–based vaccination program

  • Resources and volume. Space and human resources need to be considered when pursuing an emergency department–based vaccination program. These vaccination programs are dynamic processes and may need to adapt to the day-to-day changes in volume and resources. Emergency department resources are tightly linked to patient volume, both of which are important considerations when planning a vaccination program. Low-volume emergency departments may be unable to sustain an effective program. Conversely, high-volume emergency departments may be unable to provide vaccination during extremely busy times when their resources are low.
  • Emergency department flow. Emergency department–based vaccination needs to fit within the normal emergency department flow. Although modifications to flow may be necessary for vaccination programs, they should not lead to extended lengths of stay or negatively affect other important emergency department metrics.

Continuous monitoring of emergency department–based vaccination

  • As with other emergency department interventions, quality improvement should be applied to vaccination programs. Quality improvement programs should ensure high rates of vaccination with minimal impact on the usual emergency department care and flow. Quality improvement programs should also examine the following vaccination program metrics:
    • Patients screened for vaccination status;
    • Patients eligible for the emergency department–based vaccination program;
    • Eligible patients who are vaccinated; and
    • Reasons for vaccine refusal along with sociodemographic factors like race, age, and comorbidities in patients who refuse, when possible.
  • A quality improvement modification process like the plan-do-study-act (PDSA) cycle or another tool can integrate the lessons learned from the vaccination program to increase its success.
  • Furthermore, local vaccination rates and epidemiologic trends should be examined to assess the ongoing need for or discontinuation of the emergency department–based vaccination program.

COVID-19–specific additional considerations

  • Receiving the second dose in the emergency department
    • The emergency department vaccine program should include specific plans to ensure that first-dose vaccine recipients receive their second dose. Emergency department leadership may need to work with the hospital system to complete these plans (eg, administering second doses at an infusion center, vaccine clinics, and so on). In some unusual circumstances, emergency department patients with exceptionally high recidivism may need their second dose administered in the emergency department.
  • How to administer vaccines
  • Who can order COVID-19 vaccines
    • Standing orders are used for many emergency department functions (eg, nurses in triage routinely order an ECG). Standing orders are recognized as a proper method for ordering a COVID-19 vaccine and are fully reimbursable. Having nurses or pharmacists offer vaccination may increase uptake, especially because nurses are considered the most trusted profession.
  • Consent for vaccination
    • The CDC does not state the specific consent process to be followed for COVID-19 vaccination. Instead, the vaccine consent process is guided by individual state laws and regulations as well as institutional practices. The COVID-19 vaccination consent process follows the consent process of any vaccination in the emergency department. The COVID-19 vaccination process and risks and benefits should be discussed with each potential vaccine recipient before the recipient (or appropriate caregiver) consents to receiving the vaccine. The medical record should also contain documentation of this discussion and whether consent was verbal or written (ie, a signed consent form).
  • Delivering COVID-19 vaccine–specific information to recipients
    • When a health care worker prepares to administer a vaccine, the recipient is provided with certain vaccine-specific information, typically in written form. For other vaccines, this information is known as the vaccine information statement. The emergency department typically uses the same vaccine information statements that its hospital system uses.
  • Vaccine documentation to give to recipients
    • Vaccination documentation should follow the institutional and state guidelines in place.
  • Communication with state and federal databases
    • The vaccinating institute may communicate with local and state institutions during the vaccination program’s implementation. Emergency departments need to follow their institution’s policies and procedures for these communications.
    • Individual states often have statewide databases that track childhood vaccinations, including COVID-19 vaccines.
      • These statewide vaccine databases may have bidirectional digital information flow from an institution's electronic health record (EHR) system. The New York State Immunization Information System (NYSIIS) is an example of this type of database. Many hospitals in New York automatically include each patient’s vaccination status and events in their EHR, which then routes to the NYSIIS.
      • Importantly, emergency departments can use either their institution’s EHR for vaccine recordkeeping or their state’s vaccine recordkeeping system to identify patients eligible for vaccination.


  1. Duffy S. Why are RNA virus mutation rates so damn high? PLoS Biol. 2018 Aug 13;16(8):e3000003. doi: 10.1371/journal.pbio.3000003

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