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Recommendations for Practitioners and Manufacturers to Address System-Based Causes of Vaccine Errors

Immunizations are widely recognized as one of the most successful and cost-effective health interventions ever introduced worldwide. According to the World Health Organization (WHO), immunizations prevent between 2 and 3 million deaths per year. Despite this success, some children and adults in the US remain vulnerable to the 17 vaccine-preventable diseases targeted with specific immunization recommendations in the US. The failure to vaccinate due to lack of information or misinformation is the primary reason for the existence of susceptible populations in the US. However, errors with vaccines can result in an unintended and unrecognized source of vulnerability. While the immediate impact of a vaccine-related error on a patient may not be serious, such errors may render the vaccine ineffective or reduce its effectiveness, leaving patients unprotected against serious diseases such as hepatitis A, hepatitis B, diphtheria, tetanus, measles, cervical cancer, and many others.

In September 2012, ISMP (in cooperation with the California Department of Public Health) established the ISMP National Vaccine Errors Reporting Program (ISMP VERP) to collect data about the type of vaccine errors occurring and the reasons they occur. In our November 28, 2013 newsletter, we provided a summary analysis of error reports submitted to the ISMP VERP during its first year.

The vaccinations most frequently involved in errors included:

  • Influenza
  • Haemophilus influenzae type b conjugate (Hib)
  • Diphtheria and tetanus toxoids, acellular pertussis adsorbed, and inactivated poliovirus (DTaP-IPV)
  • Tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis adsorbed (Tdap)
  • Diphtheria and tetanus toxoids and acellular pertussis adsorbed (DTaP)
  • Hepatitis A (HepA)
  • Hepatitis B (HepB)
  • Human papillomavirus (types 6, 11, 16, 18), recombinant (HPV4)
  • Zoster
  • Measles, mumps, rubella, and varicella (MMRV)

The most common contributing factors associated with the reported vaccine errors included:

  • Mistakes in choosing age-dependent formulations of vaccines intended to prevent the same diseases
  • Unfamiliarity with the vaccine, particularly its dose, dosing schedule, age specifications, route of administration, and the vaccine’s various components (e.g., combination vaccines; diluent and powder)
  • Failure to check or verify the patient’s age, health record, or state registry
  • Similar vaccine names and abbreviations
  • Similar and confusing vaccine labeling and packaging
  • Unsafe storage conditions (e.g., stored near other similar vaccines, unwanted temperature fluctuations)
  • Expiration dates not noticed or misunderstood

In this newsletter, we provide recommendations to reduce the risk of vaccine errors. These suggestions are categorized into practice-related or manufacturer-related recommendations. We also call upon the healthcare industry to address our growing concern with vaccine errors, particularly in light of an ongoing influx of new and novel vaccines, an ever-increasing array of combination vaccines, special precautions associated with certain vaccines, and frequently changing immunization recommendations. 

Practice Recommendations

Make immunization schedules available. Post up-to-date, easy-to-read immunization schedules for infants, children, teens, and adults that staff can quickly reference in clinical areas where immunizations may be administered. Also provide parents/caregivers, teens, and adults with easy-to-read immunization schedules (available at the above web address) so they know what vaccine(s) they or their child should be receiving during visits to a healthcare provider. If a child or teen misses a particular vaccination(s), create an individualized catch-up schedule of immunization and provide it to the parent or caregiver.

Provide a VIS before vaccination. Provide patients or parents/caregivers with written information about vaccines, including the most current federal Vaccine Information Statement (VIS) in the patient’s native language. The VIS must be provided by all public and private vaccination providers each time a covered vaccination is given. Time to read the VIS before vaccination should be provided. Document in the patient’s record the publication date of the VIS and the date it was given to the patient or parent/caregiver.

Establish protocols. Establish standard order sets or protocols for frequently administered vaccines to ensure consistency with vaccine administration. The order sets or protocols should include: 1) criteria for screening patients to determine the need for vaccination, indications, contraindications, and precautions, 2) directions for administering the vaccine, including any special procedures required to enhance safety (e.g., involving the patient/parent in the checking process), 3) information regarding any required follow-up doses, 4) details regarding where to document vaccine administration, and 5) an emergency protocol to follow if the patient develops an adverse reaction. Resources to help develop order sets or protocols can be found here. Protocols and standard order sets can also help ensure that appropriate candidates receive an immunization at the right time (e.g., pneumococcal vaccine for seniors, hepatitis B vaccine for newborns).  

Educate staff. Require all healthcare professionals and assistants who immunize patients or handle vaccines (procurement, inventory management, preparation for patients) to undergo periodic training and demonstrate competencies related to the types of vaccines being administered.      

Maintain cold storage. Specify the storage requirements for each vaccine and diluent in your inventory. Most vaccines must be stored in a refrigerator or freezer maintained within a specific temperature range, and many vaccines require protection from light. Excessive heat or cold—even a single exposure, in some instances—can reduce vaccine potency. Monitor the temperature of vaccine storage units and take immediate action in response to temperature excursions. If feasible, a storage unit alarm system with wireless alerting capability for temperature fluctuations and power outages is valuable. 

Separate vaccines. Separate pediatric and adult formulations of vaccines in all storage areas, and affix auxiliary labels (Adult or Pediatric) to the vaccines and/or storage containers. Do not store vaccines with similar names or abbreviations, or overlapping component(s) (e.g., DTaP, DT, Tdap, Td) immediately next to each other. Store any newborn vaccines (HepB) separately from the mother’s medication supplies to avoid misadministration of the infant’s vaccine to the mother or mother’s medication to the newborn. If possible, administer infant medications in an area separate from where medications are administered to the mother. If more than one vaccine type must be administered, keep the vaccines separate (e.g., separate trays; separate sections of trays; separate vaccine administration stations) when feasible.    

Avoid storing pre-drawn syringes. In outpatient units and immunization clinics, the Centers for Disease Control and Prevention (CDC) and most vaccine manufacturers do not recommend drawing vaccines into syringes well in advance of administration. There are no data on the stability of vaccines stored in syringes that have been filled by providers, and bacterial contamination and growth can occur in syringes that do not contain a bacteriostatic agent. Although pre-drawing is discouraged, CDC suggests that a small number of vaccine doses may be pre-drawn and labeled if they are prepared directly at the clinic site by the practitioner administering the vaccines. At the end of the workday, any remaining vaccine in pre-drawn syringes should be discarded. As an alternative to pre-drawn syringes, the CDC recommends using manufacturers’ prefilled syringes, particularly for large immunization events. For individual inpatients, pharmacies may prepare the vaccine in a syringe and dispense it for immediate administration. If vaccines are provided in automated dispensing cabinets (ADCs) in health-systems, nurses should not remove the vaccines from the ADC before the order has been reviewed by a pharmacist.

Involve the patient/parent/caregiver in the verification process. In physician offices and community pharmacies, where individual patient immunization records are maintained, involve the patient or parent(s)/caregiver(s) in a vaccine verification process by: 1) documenting the vaccine name, formulation (pediatric or adult, if applicable), lot number, and expiration date on the patient’s vaccine record prior to preparation/administration of the vaccine, 2) bringing the vial and syringe or the prefilled syringe along with the immunization record into the exam room, 3) asking the patient or parent to simultaneously verify the information on the immunization record while a healthcare provider reads the information on the label aloud, 4) asking the patient or parent if the vaccine verified is what they expected to be administered (based on an immunization schedule provided to the patient or parent previously), 5) preparing and administering the vaccine immediately after verification, and 6) documenting the vaccine on the patient’s medical record. (This process also prevents having unlabeled syringes of vaccines.) If preparing the syringe of vaccine before entering the exam room (as one might to avoid scaring pediatric patients), be sure the syringe is properly labeled with the vaccine name and dose. Some practice sites also ask the patient or parent to initial or sign the immunization record after verification, but this can be challenging with electronic immunization records. In inpatient settings, for particular vaccines, some hospitals have initiated a time-out process to verify vaccines in a similar manner utilizing two healthcare practitioners, or one practitioner and the patient/caregiver.

Label all prepared syringes. Unless the vaccine is prepared in front of the patient in the exam room or at the bedside, and administered immediately, all vaccines prepared in syringes should be labeled. Peel-off labels to use for this purpose may be available on some manufacturer vaccine vials. We encourage widespread use of peel-off labels by manufacturers and caregivers.

Use full names or standard abbreviations. If necessary, only use standard vaccine abbreviations recommended by CDC. Do not use ad hoc abbreviations, such as “H Flu” for Haemophilus influenzae type b (which can be misinterpreted as influenza vaccine). Keep in mind that errors are still possible, even when using standard vaccine abbreviations, given abbreviation similarities (e.g., DT, Td, DTaP, Tdap) or difficulty recalling the correct abbreviations. If you permit the use of vaccine abbreviations, follow the CDC recommendations and list both the full generic name (and brand, if needed) along with the standard abbreviation on all electronic and preprinted forms to reinforce the correct use of abbreviations. Be sure your immunization records have enough space to list full vaccine names. You might also consider giving patients a copy of the larger, provider immunization record with full vaccine names, even if wallet-sized immunization cards with CDC abbreviations are provided.

Keep vaccines with diluents. If using a vaccine that requires a diluent for reconstitution or two components that must be combined (e.g., PENTACEL) before administration, keep the two vials together using a rubber band or place them together in a sealable plastic bag. (The diluent container label may emphasize the active drug, leading to erroneous administration of the diluent alone.) Affix a label to the vaccine to remind staff to use both vials. To confirm administration of both components, document the NDC number for each vial in the immunization record before administration.

Discard cartons. Consider removing vials of vaccines from their outer cartons (unless it provides the only protection from light) prior to storage to avoid the risk of misplacing a vial back into the wrong carton. Vials should be separated into bins or other containers according to vaccine type and formulation. 

Purchase oral vaccine in the safest packaging. The only oral vaccine available in the US is the rotavirus vaccine. This vaccine has been inadvertently administered via the intramuscular (IM) route, risking infection and rendering the vaccine ineffective. Of the two companies that manufacture the vaccine, one is available in an oral syringe that looks exactly like a prefilled parenteral syringe (ROTARIX). The vaccine is intended to be reconstituted with a diluent and then redrawn into the oral syringe and administered. However, some healthcare practitioners have withdrawn the reconstituted solution into a parenteral syringe and administered it IM. The other manufacturer provides the vaccine (ROTATEQ) in a squeeze applicator. While this, too, has been drawn into a parenteral syringe and administered IM, the reported incidence is much lower than with the other product and would be the preferred packaging to avoid errors.

Manufacturer Recommendations 

Manufacturers of vaccine products are strongly encouraged to revise the packaging and labeling of vaccine products as specified:

  • Display expiration dates in a standard, straight-forward way that can be understood by all. For example, an expiration date of 13MAR15 (currently used by one manufacturer) is easily misinterpreted. Does it expire March 13, 2015 or March 15, 2013? A better choice is 13March2015.
  • Provide clear instructions for mixing vaccine components on all labels of vaccine products that require reconstitution prior to administration. The diluent, if provided, should include a bold statement indicating that it is only a diluent, not the actual product.
  • Whenever feasible, consider packaging that forces proper mixing of a diluent or two component vaccines. A dual-chambered vial containing vaccine powder in one chamber and diluent in the other is one example. Another example involves packaging that binds the two vials together.
  • Improve the labeling of vaccines to clearly differentiate pediatric and adult formulations. Use larger vials as necessary to make labels more readable.
  • Make peel-off labels available to promote immediate labeling of prepared syringes and accurate documentation of administration.
  • Package vaccines in unit dose, prefilled syringes appropriate to the mode of administration (e.g., parenteral vs. oral) to minimize the need to prepare individual doses. 


There are a number of actions noted above that healthcare providers and manufacturers can take today to vastly reduce the risk of vaccine-related errors. However, a more discerning review of the issues with an interdisciplinary team that includes prescribers, pharmacists, nurses, technology vendors, pharmaceutical companies, immunization experts, professional organizations, and regulatory/standard-setting organizations, could result in additional recommendations for healthcare providers and manufacturers to follow that can help improve vaccine safety and efficacy.