FARE - Food Allergy Research & Education Logo
Education

COVID-19 Vaccine Q&A

– December 2020

FARE Update on mRNA Vaccines Against COVID-19

Vaccine

The Pfizer and BioNTech COVID-19 vaccine received emergency use authorization from the U.S. Food and Drug Administration (FDA) on December 11. Another COVID-19 vaccine, developed by Moderna, received emergency use authorization on December 18. Both vaccines are now in use. Reports of serious allergic reactions to the Pfizer and BioNTech vaccine and at least one report of serious allergic reaction to the Moderna vaccine have led to new guidance from the Centers for Disease Control and Prevention (CDC) and a plan to study what’s behind these reactions by the National Institutes of Health (NIH), with new insights coming each day. Here’s what we’ve learned so far.

***Be sure to check back here often as FARE will update this page regularly to reflect new findings and information relating to COVID-19 vaccines***

Who can receive a COVID-19 vaccine?

  • The Pfizer and BioNTech vaccine has received emergency authorization for use in individuals 16 years of age and older.
  • The Moderna vaccine’s emergency use authorization is limited to adults, aged 18 and older. NOTE: Moderna is currently studying its vaccine in children aged 12 to 17 years.
  • At this time, the CDC recommends that healthcare personnel and residents of long-term care facilities should be offered the first doses of COVID-19 vaccine.
  • Both vaccines approved to date require two doses delivered weeks apart for maximum effectiveness.
    • Both of the doses administered should deliver the same vaccine, Pfizer and BioNTech or Moderna.
    • The time between doses is 21 days for the Pfizer and BioNTech vaccine and 28 days for the Moderna vaccine.

How are the two vaccines similar? How are they different?

  • Both vaccines contain mRNA; to better understand how the vaccines work you can check out our primer on mRNA vaccines.
  • Neither vaccine contains killed or weakened virus.
  • Neither vaccine contains mercury or other preservatives.
  • Neither vaccine contains egg or other food allergens.
  • Neither vaccine is exposed to latex in its packaging.
  • Both vaccines contain lipids (fats).
    • In each vaccine, some of the lipids are attached to a molecule called polyethylene glycol (PEG) that has many uses in medicine and biology. Scientists have proposed that PEG might trigger serious allergic reactions in a small number of individuals.
  • The Pfizer and BioNTech vaccine must be stored at extremely cold temperatures, while the Moderna vaccine can be kept in more conventional cold storage. This means that more providers are equipped to store and administer the Moderna vaccine.
  • Both the Pfizer and BioNTech and Moderna vaccines are more than 90 percent effective in preventing symptomatic COVID infections.

Comparison of COVID-19 Vaccines With Emergency Use Authorization

Number of doses required?

  • Pfizer and BioNTech: Two
  • Moderna: Two

Highly effective at preventing symptomatic COVID-19 disease?

  • Pfizer and BioNTech: Yes, 95% effective
  • Moderna: Yes, 94.1% effective

Contains mRNA?

  • Pfizer and BioNTech: Yes
  • Moderna: Yes

Contains polyethylene glycol (PEG)?

  • Pfizer and BioNTech: Yes
  • Moderna: Yes

Contains virus?

  • Pfizer and BioNTech: No
  • Moderna: No

Contains preservative?

  • Pfizer and BioNTech: No
  • Moderna: No

Contains food ingredients?

  • Pfizer and BioNTech: No
  • Moderna: No

Contacts latex in packaging?

  • Pfizer and BioNTech: No
  • Moderna: No

Authorized for use in older children?

  • Pfizer and BioNTech: Yes, ages 16 and up
  • Moderna: No, ages 18 and up

Requires special storage?

  • Pfizer and BioNTech: Yes, stored in ultra-low temperature freezer between -80ºC to -60ºC (-112ºF to -76ºF)
  • Moderna: No, can be stored refrigerated between 2° to 8°C (36° to 46°F) for up to 30 days prior to first use

U.S. Food and Drug Administration,2020

According to CDC guidance:

  • If you have had a severe allergic reaction to any of the ingredients in a COVID-19 vaccine, you should not receive that vaccine.*
  • If you have had a severe allergic reaction to your first dose of COVID-19 vaccine, you should not receive the second dose.
  • If you have had a severe allergic reaction to another vaccine or injectable therapy, you should consult with your doctor, who can help you determine whether you should receive a COVID-19 vaccine.
  • If you have had a severe allergic reaction to oral medications, you can receive a COVID-19 vaccine.
  • If you have had a severe allergic reaction to allergens unrelated to vaccines or injectable drugs, such as food, pet dander, venom, environmental allergens and latex you can receive a COVID-19 vaccine.
  • If you have had allergic reactions but never had a severe allergic reaction, you can receive a COVID-19 vaccine.
  • If you have a family history of severe allergic reactions, you can receive a COVID-19 vaccine.

Can I Receive a COVID-19 Vaccine?

No

  • Severe allergic reaction to any COVID-19 vaccine ingredient*
  • Severe allergic reaction to first dose of COVID-19 vaccine

Consult with your doctor

  • Severe allergic reaction to another vaccine or injectable therapy

 

Yes

  • Severe allergic reaction to oral medications
  • Severe allergic reaction to other allergens, including foods
  • Mild allergic reactions only
  • Family history of severe allergic reactions

Centers for Disease Control and Prevention, 2020

Were severe allergic reactions to the two vaccines reported during clinical trials?

There were no serious allergic reactions reported during the clinical trials for the Pfizer and BioNTech or Moderna vaccines. However, individuals with a history of anaphylaxis were excluded from the trials.

What is being done to learn more about severe allergic reactions to COVID-19 vaccines?

The Centers for Disease Control and Prevention published a study on January 6, 2021, reporting that anaphylactic reactions to the Pfizer and BioNTech COVID-19 vaccine are very rare. During the week of December 14-23, 2020, nearly 1.9 million doses of vaccine were delivered, resulting in 21 cases of anaphylaxis, or 11.1 anaphylactic reactions per million doses of vaccine. Among the 21 individuals who had an anaphylactic reaction to the vaccine, 17 had a past history of other allergies or allergic reactions. No deaths were reported. The vaccine was reported to trigger an additional 83 non-anaphylactic allergic reactions. To learn more, click here.

At the National Institutes of Health, officials report that they are working to design a clinical study of the Pfizer and BioNTech vaccine in individuals with histories of severe allergic reaction. Researchers hope to identify the allergenic component of the vaccine.

If you have questions, please don’t hesitate to contact the FARE Communications team at media@foodallergy.org.

*The ingredients of the Pfizer and BioNTech vaccine are lipids (0.43 mg (4-hydroxybutyl)azanediyl)bis(hexane-6,1-diyl)bis(2-hexyldecanoate), 0.05 mg 2[(polyethylene glycol)-2000]-N,N-ditetradecylacetamide, 0.09 mg 1,2-distearoyl-sn-glycero-3-phosphocholine, and 0.2 mg cholesterol),0.01 mg potassium chloride, 0.01 mg monobasic potassium phosphate, 0.36 mg sodium chloride, 0.07 mg dibasic sodium phosphate dihydrate, and 6 mg sucrose. The diluent (0.9% Sodium Chloride Injection, USP) contributes an additional 2.16 mg sodium chloride per dose.
**The ingredients of the Moderna vaccine are lipids (SM-102, polyethylene glycol [PEG] 2000 dimyristoyl glycerol [DMG], cholesterol, and 1,2-distearoyl-sn-glycero-3-phosphocholine [DSPC]), 0.31 mg tromethamine, 1.18 mg tromethamine hydrochloride, 0.043 mg acetic acid, 0.12 mg sodium acetate, and 43.5 mg sucrose.

We use cookies to deliver the best possible experience on our website. To learn more, visit our Privacy Policy. By continuing to use this site, or closing this box, you consent to our use of cookies.