By all accounts, shingles is a painful disease. Originating from the same virus that causes chickenpox, shingles
results in a blistering rash on one side of the body. A mild case may clear up within a few weeks and cause no complications, while a more severe case can result in lasting postherpetic neuralgia or pain where the rash was.
Zoster vaccine live (ZVL)—or Zostavax
—a vaccine to prevent shingles, was introduced more than a decade ago and was approved by the Advisory Committee on Immunization Practices (ACIP) for use in adults aged 60 and older. Last year, a more effective vaccine, recombinant zoster vaccine (RZV)—also known as Shingrix
—became available. ACIP now recommends this vaccine for all adults aged 50 and older who are at risk of shingles (basically, anyone who ever had chickenpox) and are not immunocompromised. Shingrix differs from Zostavax in that it’s an intramuscular injection rather than a subcutaneous one, and it’s given in 2 doses anywhere from 2 to 6 months apart.
The Vaccine Adverse Event Reporting System
(VAERS), part of the Centers for Disease Control and Prevention (CDC), began monitoring Shingrix in October of 2017. Over the course of 4 months, VAERS looked at 155 reports about Shingrix, 13 of which involved at least 1 error in the administration of the vaccine. Nine of the reports involved Shingrix being administered subcutaneously rather than intramuscularly, with 8 out of those 9 administrations causing reactions such as pain, redness, and itching at the injection site. One of the 9 recipients of the subcutaneous injection was 48 years old, younger than the minimum recommended age. Two out of the 9 recipients were given the Zostavax vaccine information statement rather than the Shingrix statement. The other 4 out of 13 error reports involved 1 person of unknown age receiving Shingrix, 1 person aged 39 receiving the vaccine, 1 person receiving Shingrix after it had been incorrectly stored, and 1 person receiving only part of the vaccine without the accompanying antigen necessary for reconstitution of the vaccine. Nine of the errors took place in a pharmacy, 2 occurred in a health care provider’s office, and 2 occurred in sites that were unknown.
It’s possible that these errors occurred because providers were used to storing, handling, and administering Zostavax, which has different requirements than Shingrix does. Can such administration errors affect the efficacy of the vaccine or, even worse, pose a danger to the recipient?
“The impact of an administration error on [the] effectiveness of giving the new shingles vaccine depend[s] on the error,” Tom Shimabukuro, MD, MPH, MBA, deputy director of the CDC’s Immunization Safety Office, told Contagion ®
. “There is no evidence to suggest incorrectly giving Shingrix subcutaneously reduces the effectiveness of the vaccine; however, this may worsen side effects.”
Because Shingrix is meant to be administered in the deltoid muscle of the shoulder, injecting it underneath the skin could raise the risk of reactions at the injection site, and possibly increase their severity, according to Dr. Shimabukuro. “These reactions could include pain, redness, swelling, induration, etc. However, in this case, despite the adverse reaction the vaccine would still be effective,” he said. “Other errors—like those related to improper storage and handling or giving the second Shingrix dose too soon—may affect the effectiveness of the vaccine and require someone to get revaccinated.”
Because VAERS and CDC-INFO, the national contact center and publication fulfillment system, receive reports and information spontaneously, it’s difficult to make definitive pronouncements about whether pharmacies, doctor’s offices, hospitals, or other settings are more prone than others to vaccine errors.
“The limitations of spontaneous reporting, also known as passive monitoring, constrain our ability to draw conclusions about how often these errors occur in different types of settings, so we are unable to say definitively that they occur more frequently in any particular healthcare setting versus another,” said Dr. Shimabukuro. “The important thing to note is that vaccine administration errors are preventable, regardless of the health care setting, with proper training and adherence to established guidelines and protocols for administering vaccines.”
Ms. Saloman is a health writer with more than 20 years of experience working for both consumer- and physician-focused publications. She is a graduate of Brandeis University and the Medill School of Journalism at Northwestern University. She lives in New Jersey with her family.
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