pentacel components being administered separately with no reported adverse event; Initial information received on 22-Jan-2025 regarding an unsolicited valid non-serious case received from a nurse. This case is linked to US-SA-2025SA023518 (Cluster case). This case involves a 4 months old male patient who had Diphtheria/Tetanus/5 Hybrid Ac Pertussis/Ipv(Vero)/Hib(Prp/T) Vaccine [Pentacel (Vero)] components being administered separately with no reported adverse event. The patient’s past medical history, medical treatment(s), vaccination(s) and family history were not provided. Concomitant medications included PNEUMOCOCCAL VACCINE for Immunisation. On 21-Jan-2025, the patient received a 0.5 ml dose of suspect Diphtheria/Tetanus/5 Hybrid Ac Pertussis/Ipv(Vero)/Hib(Prp/T) Vaccine (lot 49281-561-01 and 49281-51105, with strength as Standard and unknown expiry) via intramuscular route in the left thigh as Immunization, but on this date only the DTaP-IPV liquid vaccine component was administered and next day on 22-Jan-2025 received an unknown dose of ActHIB vaccine component via intramuscular route in the right thigh leading to pentacel components being administered separately with no reported adverse event (wrong technique in product usage process) (Latency: same day). Reportedly, Caregiver is unsure if the ActHIB that was administered today was the lyophilized vaccine component of PENTACEL from yesterday or if it was the actual vaccine. This suspected adverse reaction report is submitted and classified as a medication error solely and exclusively to ensure the marketing authorization holder’s compliance with the requirements set out in the Directive 2001/83/EC and Module VI of the Good Pharmacovigilance Practices. The classification as a medical error is in no way intended, nor should it be interpreted or construed as an allegation or claim made by the marketing authorization holder that any third party has contributed to or is to be held liable for the occurrence of this medication error.; Sender’s Comments: US-SA-2025SA023518:02383817