COVID-19 Vaccine FAQs
Answers to the most frequently asked questions on Covid-19 vaccines, from the American Nurses Association and the American Society of Health-System Pharmacists
Question: What are the differences in technology development between the vaccine candidates?
Answer: There are several platforms being used to develop the COVID-19 vaccine candidates. They are briefly explained in the table below..
| Type | Description | Example |
| mRNA | Fragments are inserted into human cells to reprogram them to produce pathogen antigens, which stimulate an immune response against the pathogen. How it works: https://www.youtube.com/watch?v=w4sUuFBEo2g |
Pfizer / BioNTech Moderna |
| Viral Vector | Nonreplicating Vector – Based on recombinant viral vectors that are sufficient to induce host immune responses but cannot replicate inside host cells. How it works: https://www.gavi.org/vaccineswork/what-are-viral-vector-based-vaccines-and-how-could-they-be-used-against-covid-19 |
Johnson&Johnson/Janssen candidate Oxford/AstraZeneca candidate |
| Protein-Based | Vaccine made from small proteins or peptides that contain epitopes that are then presented to and recognized by T-cells as target tumor antigen and generate an immune response. How it works: https://www.gavi.org/vaccineswork/what-are-protein-subunit-vaccines-and-how-could-they-be-used-against-covid-19 |
Novavax candidate |
Additional Resources:
- Centers for Disease Control and Prevention (CDC) COVID-19 Website: https://www.cdc.gov/coronavirus/2019-ncov/your-health/index.html
- ASHP Vaccine Candidate Tracking Table: https://www.ashp.org/-/media/assets/pharmacy-practice/resource-centers/Coronavirus/docs/Vaccine-candidate-tracking-table.ashx
- CDC Understanding and Explaining mRNA COVID-19 Vaccines: https://www.cdc.gov/vaccines/covid-19/hcp/mrna-vaccine-basics.html
Question: What are the various regulatory review pathways that the FDA can consider in order to release a vaccine (BLA, EUA, Expanded access)
Answer: The regulatory approval pathways are summarized below. The FDA will rely on the Vaccines and Related Biological Products Advisory Committee (VRBPAC) to make recommendations based on its evaluation of safety, efficacy, and appropriate use data available for the COVID-19 vaccine candidates.
Biologics License Application (BLA):
Once preclinical and clinical development programs have been successfully completed, companies submit a BLA to the FDA. A BLA is a comprehensive submission which includes preclinical and clinical data and information, as well as details of the manufacturing process and facility(ies). The BLA is the official request for permission to introduce a biologic product, including a vaccine, into interstate commerce.
Emergency Use Authorization (EUA):
During a public health emergency, if certain criteria are met, manufacturers may submit a request for EUA to FDA to facilitate the availability and use of their vaccine during this time.
Under an EUA, the Commissioner may allow unapproved drug, unlicensed vaccine, or uncleared device to be used in a public health emergency to diagnose, treat, or prevent serious or life-threatening diseases or conditions caused when there are no adequate, approved, and available alternatives.
The EUA process is different than an FDA approval or clearance. With each EUA decision, FDA weighs known and potential benefits of product against known and potential risks.
- EUAs helped speed access to COVID-19 diagnostic tests, N95 respirators, and remdesivir.
- COVID-19 vaccines: FDA prefers phase-3 studies be completed. EUA sooner could impair efficacy + safety determination.
Expanded access:
This allows investigational drugs, biologics, or medical devices that have not yet been approved or cleared by FDA to be used for a patient with an immediately life-threatening condition or serious disease for treatment outside of clinical trials when no comparable or satisfactory alternative therapy options are available.
Currently, expanded access is one pathway for use of COVID-19 convalescent plasma for patients with serious or immediately life-threatening COVID-19 disease who are not eligible for or who are unable to participate in randomized clinical trials.
Additional Resources:
- Understanding the Regulatory Terminology of Potential Preventions and Treatments for COVID-19
- FDA BLA Resources
- FDA EUA Guidance: https://www.fda.gov/media/97321/download
- FDA Vaccines and Related Biological Products Advisory Committee https://www.fda.gov/advisory-committees/blood-vaccines-and-other-biologics/vaccines-and-related-biological-products-advisory-committee
Question: What are the storage and handling considerations for the leading vaccine candidates?
Answer: Due to the formulation of the vaccine, the storage conditions of the two vaccine candidates leading in the U.S. require negative temperatures. The other vaccine candidates appear to be stable at refrigerated temperatures.
The Pfizer/BioNTech vaccine must be stored at ‐70°C and will last for up to 5 days at refrigerated temps (2°‐8°C). Thermal shippers can be room temp for 10 days (some sources indicate 15 days) if they are replenished with Dry Ice. Prior to administration, the vaccine must be thawed (to be used within 5 days) and reconstituted with diluent and used within 6 hours.
The Moderna vaccine must be stored at -20°C, and can be stored for up to 6 months. The vaccine will be stable at refrigerated temperatures of 2 to 8°C for 30 days. All doses in vial must be administered within 6 hours after vial puncture.
In the event there is overfill remaining after 5 doses of the Pfizer/BioNTech and 10 doses of Moderna vaccine have been administered, the FDA has indicated that the remaining dose can be used as long as there is enough vaccine remaining for a full dose (0.3 mL for Pfizer/BioNTech and 0.5 mL of Moderna) and doses are not pooled.
Additional Resources:
- CDC Vaccine Storage and Handling Toolkit https://www.cdc.gov/vaccines/hcp/admin/storage/toolkit/index.html
- USP Vaccine Handling Toolkit: Operational Considerations for Healthcare Practitioners https://www.usp.org/covid-19/vaccine-handling-toolkit
Question: What does the CDC say about the dosing schedule and interchangeability of the Pfizer/BioNTech and Moderna vaccines?
Answer: The CDC recently updated recommendations on intervals between the first and second dose and interchangeability of vaccine product, updated language on vaccination of persons with a history of SARS-CoV-2 infection, and new vaccination recommendations in persons with a history of dermal fillers. Regarding the intervals, “The second dose should be administered as close to the recommended interval as possible. However, if it is not feasible to adhere to the recommended interval, the second dose of Pfizer-BioNTech and Moderna COVID-19 vaccines may be scheduled for administration up to 6 weeks (42 days) after the first dose. There are currently limited data on efficacy of mRNA COVID-19 vaccines administered beyond this window. If the second dose is administered beyond these intervals, there is no need to restart the series.”
On the issue of interchangeability of vaccine product, the CDC states that the products are not interchangeable with each other and that safety and efficacy of a mixed-product series have not been evaluated. Both doses of the series should be completed with the same product. The CDC further states, “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.”
Additional Resources:
- CDC Interim Clinical Considerations for Use of mRNA COVID-19 Vaccines Currently Authorized in the United States https://www.cdc.gov/vaccines/covid-19/info-by-product/clinical-considerations.html
Question: What are immediate side effects to expect from the COVID-19 vaccine?
Answer: As your body gets used to the COVID vaccine in your system it is common to have minor effects. Reported symptoms include pain at the injection site, fever, fatigue, and headaches and are worse after the second dose. Other symptoms can include muscle and joint pain, cough, feeling ‘hungover’, and shortness of breath.
Additional Resources:
- CDC COVID-19 Site - https://www.cdc.gov/coronavirus/2019-ncov/vaccines/index.html
Question: Is it safe for me to get a COVID-19 vaccine if I am planning to get pregnant in the future?
Answer: Yes. People who want to get pregnant in the future may receive the COVID-19 vaccine. Based on current knowledge, experts believe that COVID-19 vaccines are unlikely to pose a risk to a person trying to become pregnant in the short or long term.
Additional Resources
- CDC Facts about the COVID-19 Vaccines https://www.cdc.gov/coronavirus/2019-ncov/vaccines/facts.html
- CDC Vaccination Considerations for People who are Pregnant or Breastfeeding https://www.cdc.gov/coronavirus/2019-ncov/vaccines/recommendations/pregnancy.html
- Vaccinating Pregnant and Lactating Patients Against COVID-19 https://www.acog.org/clinical/clinical-guidance/practice-advisory/articles/2020/12/vaccinating-pregnant-and-lactating-patients-against-covid-19
Question: What should I do if I or a patient experiences an adverse event from the vaccine?
Answer: Monitoring for safety signals of the new vaccines against SARS-CoV-2 after their approval and/or authorization is an important responsibility of the vaccinating workforce. In addition, it is an expectation outlined in the CDC COVID-19 Vaccination Program Provider Agreement. An “adverse event following immunization” is an adverse health problem or condition that happens after vaccination. To continuously monitor the safety of the new COVID-19 vaccines, the CDC will be leveraging existing vaccine safety monitoring infrastructure, including the Vaccine Adverse Event Reporting System (VAERS), Vaccine Safety Datalink, and Clinical Immunization Safety Assessment Project. Healthcare organizations often have internal safety reporting systems as well. Healthcare providers are required by law to report to VAERS when any adverse event listed in the VAERS Table of Reportable Events Following Vaccination occurs within the specified timeframe and when an adverse event listed by the vaccine manufacturer as a contraindication to future doses of the vaccine occurs.
Additional Resources:
- CDC COVID-19 Vaccination Program Provider Agreement: https://scdhec.gov/sites/default/files/media/document/COVID19-Vaccination_Program_Provider_Agreement_and_Profile_Form.pdf
- Vaccine Adverse Event Reporting System: https://vaers.hhs.gov/index.html
- Vaccine Safety Datalink: https://www.cdc.gov/vaccinesafety/ensuringsafety/monitoring/vsd/index.html
- Clinical Immunization Safety Assessment Project: https://www.cdc.gov/vaccinesafety/ensuringsafety/monitoring/cisa/
- VAERS Table of Reportable Events Following Vaccination: https://vaers.hhs.gov/docs/VAERS_Table_of_Reportable_Events_Following_Vaccination.pdf
Question: Will it be mandatory for nurses, pharmacists, and other health care workers to receive the vaccine?
Answer: According to the best and most current evidence outlined by the Centers for Disease Control and Prevention (CDC) and the Advisory Committee on Immunization Practices (ACIP), effective protection of the public health requires that all individuals receive immunizations against vaccine-preventable diseases (VPDs). A vaccine mandate is possible for health workers; however most employers are making it voluntary until more efficacy and safety information is available. Mandatory vaccination is generally controlled by employers as a condition of employment. For example, hospitals often require employees to obtain an influenza or hepatitis B vaccine. Employers may allow for exemptions, such as medical contraindication.
ANA and ASHP strongly recommend that registered nurses and pharmacists be vaccinated against VPDs, including COVID-19 to protect themselves, their patients, and their communities. However, we recognize as trained healthcare professionals, nurses and pharmacists expect a well-established efficacy safety profile in order to make an informed decision. We do not believe health care professionals should be retaliated against if they choose not to be vaccinated. In addition, COVID-19 vaccines authorized by the FDA through an EUA carry additional allowances to accept or refuse the product that will factor into mandatory vaccination policies.
Question: How can I help stop the spread of COVID-19 vaccine misinformation?
Answer: As trusted healthcare professionals, patients will look to nurses and pharmacists for reliable information about the COVID-19 vaccine(s). Demand for the vaccine will increase in line with increased confidence from the immunizing and healthcare professional community. Address patient concerns and hesitancy with transparency, accuracy, and empathy. As we get closer to an authorization/approval for a COVID-19 vaccine(s), resources and campaigns are being developed to support nurses and pharmacists in promoting patient willingness to be vaccinated. The CDC Vaccinate with Confidence program will deploy products and tools aimed at reinforcing trust, empowering healthcare providers, and engaging communities and individuals. For example, they will release a “Journey of a COVID-19 Vaccine” infographic that emphasizes the steps followed to ensure safe and effective vaccine research and development and a “Talking to patients about COVID-19 vaccines” slide deck for healthcare professionals.
Additional Resources:
- CDC Vaccinate with Confidence program: https://www.cdc.gov/vaccines/partners/vaccinate-with-confidence.html
- CDC Talking to Patients about COVID-19 Vaccines: https://www.cdc.gov/vaccines/covid-19/hcp/index.html
- CDC Continuing the Journey of a COVID-19 Vaccine: https://www.cdc.gov/vaccines/covid-19/downloads/journey-of-covid-19-vaccine-508.pdf