Maine Department of Health & Human Services sent this bulletin at 06/04/2025 03:28 PM EDT
To: Maine Immunization Program
From: Maine Immunization Program Providers
Subject: Guidance on Air Bubbles in MenB (Bexsero) Vaccine
Date: June 4, 2025
Guidance on Air Bubbles in MenB (Bexsero) Vaccine
The Maine Immunization Program wants to make provider locations aware of some recent concerns raised regarding difficulty or inability to expel air bubbles from a prefilled syringe (called “OnePFS”) presentation of Bexsero (Meningococcal Group B Vaccine).
GSK vaccines and diluents delivered in prefilled syringes typically contain an air bubble (also known as “head space”) that results from the manufacturing process. Given that the air volume in the prefilled syringe is typically between 0.2–0.3 cc, product quality and safety assessments have concluded that this does not affect product quality or safety.
Key Guidance for Providers:
Do not discard vaccine due to air bubbles – these will be absorbed.
Vaccines containing small air bubbles do not need to be wasted and can be administered safely.
Providers should NEVER determine a vaccine is spoiled without contacting the manufacturer. This includes discoloration, temperature excursions, and any other wastage reason outside broken vials or expiration.
"Some single-dose manufacturer-filled vaccines come with an air pocket in the syringe chamber. Do we need to expel the air pocket before vaccinating? ...
No. You do not need to expel the air pocket. The air will be absorbed."
“It is not wrong to expel the air from syringes filled by manufacturers, but typically it is such a small amount of air (0.2–0.3 cc) that it is CDC’s opinion that it would not cause a problem.
When the syringe is inverted during an injection, that small amount of air would typically just clear the medication from the needle.”
Resources:
GSK Slide Summary:Bexsero Air Bubble in OnePFS Presentation(PDF): This one-page manufacturer summary confirms that small air bubbles in the prefilled Bexsero syringe are expected and safe for administration.
