Three patients received the Jynneos vaccine intramuscularly; 38-year-old male patient received the first dose of Jynneos intradermally; 38-year-old male patient received second dose of Jynneos 160 days after the first dose; Case reference number US-BN-2023-000383 is a spontaneous case report initially received from a nurse via Bavarian Nordic on 06-Mar-2023, and concerns three patients: 33-year-old male patient MR, 34-year-old female patient, and a 38-year-year old male patient.  The patients' medical history and concomitant medication details were not provided.   *On 24-Sep-2022*, one of the three patients was vaccinated with the first dose of Jynneos *(batch number FDP00018) administered intradermally (explicitly coded as 'intradermal injection')* at an unknown dose or site of administration, *for an indication of self-determined vaccination, at risk.*  On 03-Mar-2023, *160 days after the first Jynneos dose*, that patient was vaccinated with the second dose of Jynneos (batch number FDP00019, expiry date: 31-Oct-2024) intramuscularly (explicitly coded as 'inappropriate route of vaccination') in the left deltoid at 0.5 mL *(explicitly coded as 'inappropriate schedule of vaccine administered')*.   On the same day, two other patients were vaccinated with the first dose of the Jynneos vaccine (batch number: FDP00019, expiry date: 31-Oct-2024) intramuscularly (explicitly coded as 'inappropriate route of vaccination') in the left deltoid at 0.5 mL and at an unknown site of administration, *for an indication of self-determined vaccination, at risk.*   At the time of the follow-up report, it was confirmed that none of the patients experienced any adverse event after Jynneos vaccination.  All follow-up information is blended into the case narrative above, with the latest information presented between asterisks (*).  Follow-up information received from the nurse on 13-Mar-2023. New information included: the number of patients involved due to which captured verbatim was updated appropriately, patient details, dose number, batch number, and dosage for doses administered intramuscularly and conformation that none of the patients experienced any adverse event.  Follow-up information received from the nurse on 21-Mar-2023: New information included the anatomical site of administration for all three patients, and information about the first dose for the patient who received two doses.  Follow-up information received from a nurse on 28-Mar-2023: New information included information for the first dose of Jynneos vaccine of the 38-year-old patient, two new non-events, an indication for vaccination for all three patients, and confirmation that no further information was available.; Reporter's Comments: This case report concerns three patients: a 33-year-old male patient, a 34-year-old female patient and a 38-year-year old male patient. On an unspecified date, one of three patients was vaccinated with the first dose of Jynneos vaccine, administered intradermally for self-determined vaccination, as reported. 160 days after the first Jynneos dose, that patient was vaccinated with the second dose of Jynneos, administered intramuscularly, which is considered as inappropriate route of vaccination and inappropriate schedule of vaccine administered. On the same day, two other patients were vaccinated with first doses of the Jynneos vaccine, administered intramuscularly, which is considered as inappropriate route of vaccination. Incorrect route of product administration, inappropriate schedule of vaccine administered and intradermal injection are listed per company convention. No associated adverse events were reported. The patients' medical history and concomitant medication details were not provided. Inappropriate route of vaccination, inappropriate schedule of vaccine administered and intradermal injection are assessed as not related to Jynneos, but to a human factor. The case is non-serious.; Sender's Comments: This case report concerns three patients: a 33-year-old male patient, a 34-year-old female patient and a 38-year-year old male patient. On an unspecified date, one of three patients was vaccinated with the first dose of Jynneos vaccine, administered intradermally for self-determined vaccination, as reported. 160 days after the first Jynneos dose, that patient was vaccinated with the second dose of Jynneos, administered intramuscularly, which is considered as inappropriate route of vaccination and inappropriate schedule of vaccine administered. On the same day, two other patients were vaccinated with first doses of the Jynneos vaccine, administered intramuscularly, which is considered as inappropriate route of vaccination. Incorrect route of product administration, inappropriate schedule of vaccine administered and intradermal injection are listed per company convention. No associated adverse events were reported. The patients' medical history and concomitant medication details were not provided. Inappropriate route of vaccination, inappropriate schedule of vaccine administered and intradermal injection are assessed as not related to Jynneos, but to a human factor. The case is non-serious.