COVID-19 vaccination safe in children with prior reactions, pre-existing conditions

Key takeaways:

• Testing involved six children with a history of prior reactions and four with pre-existing conditions.
• The authors concluded that nine of these children could safely receive an mRNA vaccine in the future.

Children with a history of allergy to COVID-19 vaccines or pre-existing conditions that put them at higher risk for a reaction safely tolerated testing and challenges, according to a letter published in Clinical and Translational Allergy.

These outcomes were similar to those reported for adults with prior histories of allergy to COVID-19 vaccines or pre-existing conditions indicating higher risk for a reaction, Rishabh Kulkarni, immunology department, Sir Charles Gairdner Hospital, Nedlands, Australia, and colleagues wrote.

Ten children aged 8 to 15 years with a reported history of allergy to COVID-19 vaccines or who had a pre-existing condition were referred to the immunology service at Perth Children’s Hospital.

Six of these children had hypersensitivity reactions with cutaneous symptoms including urticaria and angioedema. Five had received the Pfizer-BioNTech Comirnaty (BNT162b2) vaccine, and one had received the Moderna Spikevax (mRNA 1273) vaccine, both of which are mRNA vaccines.

Three of these children had these reactions, with one of these three also experiencing throat tightness, after receiving their first dose of the vaccine. The other three experienced reactions after receiving both doses.

Challenges for these six children began with skin prick testing and intradermal testing, followed by a graded vaccine challenge when the skin testing was negative.

Four of these skin tests were negative, and two of these children with negative tests had a successful challenge to the culprit vaccine. The other two with negative tests were not challenged because they already were fully vaccinated based on the current guidelines.

Also, one of the other two children had an equivocal skin test for Comirnaty but was negative for Spikevax. The Spikevax challenge was negative, and there were no adverse events. Skin tests for Comirnaty and Spikevax both were positive for the remaining child.

This child had previously received two Comirnaty vaccines with similar mild localized cutaneous reactions. Since he had completed his primary vaccine course, he was not challenged, but he was advised to avoid mRNA vaccines.

Also, this child was negative for the Novavax (NVX-CoV2373) vaccine, which the authors called a potential alternative for future vaccination.

Among the other four children, two had mastocytosis, one had mast cell activation syndrome and one had idiopathic anaphylaxis managed via 150 mg doses of omalizumab (Xolair; Genentech, Novartis) administered every other week. These children were directly challenged under medical supervision without skin testing. All these challenges were successful, and there were no adverse events.

None of the 10 patients had any premedication before their challenges, nor were there any delayed reactions.

These results indicated that nine of these 10 children could safely use at least one brand of mRNA COVID-19 vaccine in the future, the authors said, and results reflected other studies involving adults who tolerated second vaccine doses after adverse reactions to the first.

Considering lagging rates of vaccination among children and persisting fears of allergic reactions, the authors called for more global pediatric data on allergic and adverse reactions in addition to trials pertaining to optimal management to mitigate these fears and improve these rates.