Here’s How to Avoid a COVID-19 Vaccine Mix-Up

Recognizing the potential for vaccine administration errors with identical vials, CDC staffers shared best practices for administering the right vaccine to the right person at the right dose during a Clinician Outreach and Communication Activity (COCA) webinar earlier this week.

The most worrisome potential vaccine error would be that a child could receive a higher dose of the vaccine than indicated for their age due to the possibility of increased reactogenicity — for example, an arm that hurts more than normal or a fever — Elisha Hall, PhD, clinical guidelines director and health education specialist for the CDC, said MedPage today in a subsequent phone call.

In the case of an adult who was accidentally dosed for a child, “it’s less about safety and more about immunology,” she said.

One strategy to avoid vaccine mix-ups is to be aware of the similarities between vials for different ages and purposes.

Pfizer/BioNTech

Both the Pfizer monovalent primary series vial and the bivalent booster series vial for persons 12 years and older have edge labels and caps that are an identical gray color. The total dose amounts are the same for both, but the monovalent vaccine targets only the ancestral strain of the virus, while the bivalent vaccine contains components that target both the ancestral strain and the Omicron BA.4/BA.5 strain.

Distinguishing vials by cap color is not very effective because once a multi-dose vial is ready to be punctured, “that cap is gone and the color identifier is gone”.

So it’s more important to pay attention to the label and the title, Hall said.

Unfortunately, in the case of Pfizer, the borders are the same color for both the bivalent and monovalent vaccine vials. The only significant difference is the wording:

• Monovalent vaccine: “Pfizer-BioNTech COVID-19 Vaccine”
• Bivalent vaccine: “Pfizer-BioNTech COVID-19 Vaccine, Bivalent: Original and Omicron BA.4/BA.5”

Fortunately, the cut-off label for the 5-11 year old primary vaccine is different, Hall noted.

modern

For the Moderna vaccine, there are some apparent differences in appearance between the vials of the monovalent vaccine (first series dose for people 12 years and older) and the bivalent booster vaccines (for adults 18 years and older). The cap of the monovalent vial is red while the bivalent vaccine vial is dark blue, which is only useful for vials that have not yet been opened and used.

In addition, the color of the label edge for the monovalent vaccine is light blue, while the color of the label edge for the bivalent vaccine is grey.

The caps of the monovalent child dose (primary series for those aged 6 to 11 years) and the bivalent vaccine booster dose (for adults 18 years and older) are both dark blue. However, the color of the label edge for the monovalent vaccine for children 6 to 11 years of age is purple and the color of the label edge for the bivalent booster vaccine for children 18 years and older is grey.

To add to the confusion, the vaccine label for the first series of vaccines for the 6- to 11-year-old group says “booster doses only,” because when the vaccines for young children were first approved, the appropriate vials were not available, but the Dose for this age group is the same as the dose of the original Moderna monovalent booster dose for adults.

The most anticipated error “would probably be confusing the 6-11 monovalent product with the 18-year-old and older bivalent product,” noted Hall.

As best practices for avoiding vaccine vial mix-up, Hall listed the following tips in her COCA presentation:

• Separate vaccines into different containers based on their formulation
• Use color-coded identification labels on vaccine storage containers for similar vaccine products
• Store identical vaccines in different areas of a storage unit
• Circle any important information on the package that highlights differences between vaccines
• Use identical stickers on packages and in areas where the vaccines are stored

CDC also made several recommendations for safe preparation and administration:

• Establish a “do not disturb” period when preparing or administering vaccines
• Prepare the vaccine for only one patient at a time
• Label the syringe with the vaccine name
• Never give a vaccine prepared by someone else
• Always triple check your work and, if possible, ask another member of staff to check for you

Many pharmacies and doctor’s offices only use one vaccine product, either Moderna or Pfizer, Hall noted. And those who lead both can set days for each – for example, Moderna on Monday. Providers may also choose to set a day for children’s vaccinations and another for adults.

If a vaccine delivery error occurs, the next action depends on the type of error encountered.

Bivalent booster dose

If a bivalent Pfizer vaccine is given instead of a monovalent Pfizer primary series vaccine, the CDC recommends Not Repeat the dose and count instead.

If a bivalent Moderna vaccine is administered in place of a dose of a Moderna primary series vaccine, Hall advised that a monovalent dose be administered immediately thereafter with no minimum interval as a booster dose, “because administration of the booster dose results in a lower than the approved dose for the primary series.” .”

This interval can be extended for people at high risk of a reaction, such as myocarditis or pericarditis.

Monovalent vaccine dose

If a monovalent vaccine dose is inadvertently administered in place of a bivalent booster and a bivalent booster is indicated, the CDC recommends that individuals 12 years and older not repeat the dose, but a provider may give a bivalent booster as a booster dose. based on clinical judgment and patient preference,” noted Hall during the webinar. Any repeat dose should be administered no earlier than 2 months after the accidental dose.

Next Steps

For vaccine administration errors, physicians should inform the patient, contact the state program, and report the error to the Vaccine Adverse Events Reporting System (VAERS). Hall also stressed the need to investigate how the bug occurred in order to develop strategies to ensure it doesn’t happen again.

Overall, the CDC has not identified any additional adverse events associated with reports of vaccination errors, Hall said in a follow-up email.

On August 21, the only report of serious adverse events associated with a vaccine error related to a “syringe malfunction,” she noted. The vaccine leaked or was injected into a child with a history of eczema, resulting in a split dose, she noted.

The child then received a full dose during the same visit. She developed a “general skin rash” and “lip swelling” later that same day and “met the case definition for anaphylaxis” based on this description.

Some side effects could be “random events” and others real side effects, she noted.

As for whether there has been an increase in vaccination errors since the bivalent booster doses were approved, Hall said it is “too early” to say and “the data are too sparse”.

Hall recommended consulting the detailed table attached to the CDC’s interim recommendations for all other concerns, which focuses on failures and deviations in COVID-19 management.