Immunization error related reaction and Case study

Definition: Immunization error-related reactions are AEFI that is caused by inappropriate vaccine handling, prescribing or administration and thus by its nature is preventable

These reactions are preventable and the main focus in these reactions are on the nature of the error rather than on the biologic process giving rise to the specific AEFI. 

Types of Immunization error related reactions:

(1) Error in vaccine handling:

• a. Exposure to excess heat or cold as a result of inappropriate transport, storage or handling of the vaccine (and its diluent where applicable)
  • Examples:
    • (i) Failure to vaccinate as a result of inactivation of the active vaccine components
    • (ii) Systemic or local reactions due to changes in the physical nature of the vaccine such as agglutination of aluminium- based excipients in freeze-sensitive vaccines.
• b. Use of a product after the expiry date
  • Example:
    • (i) Failure to vaccinate as a result of loss of potency or non- viability of an attenuated product.

(2) Error in vaccine prescribing or non-adherence to recommendations for use:

• a. Failure to adhere to a contraindication
  • Examples:
    • (i) Anaphylaxis following administration of a vaccine to an individual known to have an immune-mediated hypersensitivity to one or more components.
    • (ii) Disseminated infection with an attenuated live vaccine agent following administration to an individual with a known immunodeficiency that contraindicated use of any live vaccines
    • (iii)Vaccine-associated paralytic polio in an immunocompro- mised household contact of a child given oral polio vaccine.
• b. Failure to consider appropriately warnings or precautions for vaccine use.
• c. Failure to adhere to vaccine indications or prescription (dose or schedule).
  • Examples:
    • (i) Systemic and/or local reactions following administration of incorrect dose
    • (ii) Systemic and/or local reactions following administration of wrong product or administration to an individual in an incorrect age group
    • (iii) Vaccine failure if a live attenuated product is given too soon after blood products or at an age when maternally transferred antibody could interfere with replication required to induce an immune response
    • (iv) Neurologic, muscular, vascular or bony injury due to incorrect injection site, equipment or technique.

(3) Error in administration:

• a. Use of an incorrect diluent or injection of a product other than the intended vaccine
  • Examples:
    • (i) Failure to vaccinate due to incorrect diluent
    • (ii) Reaction due to the inherent properties of whatever was administered other than the intended vaccine or diluent.
• b. Incorrect sterile technique or inappropriate procedure with a multi-dose vial
  • Example:
    • (i) Infection at the site of injection due to a microbial contami- nant introduced during administration of the vaccine
    • (ii) Infection beyond the site of injection due to a microbial con- taminant introduced during administration of the vaccine.
• c. Failure to ensure a safe environment during and immediately following immunization
  • Examples:
    • (i) Head injury during a syncopal episode post-immunization.
• d. Inadvertent administration of vaccine to someone for whom it was not intended, e.g. via a needle stick injury or splash to the eye depending on the vaccine characteristics).

Case Study:

A case of sterile abscess in an eight-month-old baby, after the administration of first dose of Hepatitis B Vaccination, possibly due to an error.

Case Description:

A full-term baby boy, birth weight 3.4 kg received intradermal injection of BCG on his left arm, Hepatitis B vaccine intramuscularly on right thigh and oral Polio vaccine 8 hours after birth. The baby received Hepatitis B vaccine (each dose of 0.5 mL contains Purified HBsAg >10 microgram, Aluminium hydroxide gel equivalent to AL +++ 0.25 mg and Thiomersal IP 0.025 mg). Subcutaneous administration of aluminium salt containing vaccines can result in cyst, necrotic breakdown and sterile abscess formation. WHO’s vaccine safety basics learning manual suggests, to administer the aluminium containing vaccines intramuscularly and not subcutaneously to ensure the safety of vaccination.

A month later his mother noticed a lump in the right thigh at the site of Hepatitis B injection. As the lump was asymptomatic and non-progressive, mother waited until the 6 weeks vaccination visit to consult the Paediatrician. After examining the lump, the paediatrician informed the parents that the lump may disappear within a few weeks and did not require any intervention. The baby was given subsequent doses of Pentavalent Vaccine and Inactivated Polio Vaccine (IPV) injections on his left thigh only. Baby completed all the recommended vaccinations until the age of eight months.

The lump was left untreated until eight months and later started to show progressive enlargement and became very visible. As the lump showed progressive enlargement, mother consulted the Paediatrician again and on examination, the baby showed no pain response when pressure was applied on the lump. Ultra-sonogram of the right thigh revealed a 4.3 cm × 1.5 cm irregular hypo-echoic lesion in the subcutaneous plane with Colour Doppler showing no internal vascularity. The lesion had a thick irregular wall and a small tract was seen from the lesion to the skin surface. Paediatric surgeon made a provisional diagnosis of post-injection abscess. A tissue biopsy was obtained for culture and yielded no growth. The medical history of the baby was not suggestive of any immuno-deficiency status.

The final diagnosis was made as sterile abscess following vaccination. Incision and drainage procedure was performed by the pediatric surgeon after giving a prophylactic dose of an antibiotic, ceftriaxone 50 mg/Kg/day (intramuscular). The antibiotic was continued for three more days along with Ibuprofen 4 mg/kg thrice daily and mupirocin ointment twice daily for local application. The baby recovered completely on fifth day post-drainage and no recurrence was observed. The parents were educated about the importance of completing the immunisation schedule. The baby was followed until the age of one year and he received remaining vaccinations in the same immunisation clinic without any complication. However, no further vaccinations were given on the right thigh.

In this case, causality assessment of the AEFI was performed according to the user manual for the WHO classification and based on the algorithm, causality of the event was classified as ‘consistent causal association to vaccination’ with the sub-class ‘immunisation error related reaction’. Sterile abscess due to a delayed hypersensitivity reaction to aluminium salt adjuvant present in the vaccine may be unlikely in this case, as there was no recurrence of sterile abscess following administration of further doses of vaccines with similar components including aluminium salt. Hence the reaction may be an immunisation error related reaction due to an error in the injection technique. The possible injection technique error occurred, in this case, may be the non-deep injection of Hepatitis B.

References:

• CIOMS-WHO Working Group on Vaccine Pharmacovigilance
• Sterile Abscess Following Hepatitis B Vaccination in a New Born- A Case Report by Jisha Myalil Lucca
• EMA Guidelines on the conduct of pharmacovigilance for vaccines.