A baby had a fever of 105 degrees (rectal reading) the day after receiving the first dose of Vaxelis; This serious spontaneous safety report with reference # 02426963 (Interaction # 02426954, Case ID # 5004U00001ATc7aQAD) was received by partner on 13-JUL-2023 from a consumer on behalf of a physician and forwarded on 14-JUL-2023.  An infant of unknown age with no relevant medical history reported, had been vaccinated with Vaxelis (dose number unknown) on an unknown date (Batch # unknown) for prophylaxis.   No concomitant medication was reported.  A consumer reported on behalf of a physician, that a baby had a fever of 105 degrees (rectal reading) the day after receiving the first dose of Vaxelis. It was reported the fever went down within twenty-four hours and no further information was available.  At the time of this report, the outcome of the event, "A baby had a fever of 105 degrees (rectal reading) the day after receiving the first dose of Vaxelis" was unknown.  The reporter assessed the causal relationship between Vaxelis and the event, "A baby had a fever of 105 degrees (rectal reading) the day after receiving the first dose of Vaxelis" as related.  Further information is expected.   Significant Follow-up information was received by the partner on 25-JUL-2023 and forwarded on 26-JUL-2022, from a consumer on behalf of a physician.  A consumer reported on behalf of a physician that 2-month-old infant with relevant medical history of normal birth weight of 7 pounds 3.3 ounces and umbilical hernia, had been vaccinated with Vaxelis on 06-JUL-2023 (Batch # U7536AA exp. date 30-Sep-2025) for prophylaxis. A baby had a fever of 105 degrees (rectal reading) the day after receiving the first dose of Vaxelis on 07-JUL-2023 and the event resolved the same day.  COMPANY COMMENT:  Pyrexia is assessed as non-serious.  Pyrexia is listed for Vaxelis as per the safety information.  In agreement with the reporter and the current knowledge on Vaxelis (Pyrexia is listed as per safety information), no confounding factors (co-suspect vaccine), no prior medical history of fever reported, and that the event occurred within one day of vaccination and despite the lack of information in this case (other medical history), the causal relationship between Vaxelis and the event Pyrexia is assessed as related.   This single individual case safety report does not modify the benefit/risk balance of this product. Therefore, no change in the label or other measures is recommended at this time. However, the company will continue to monitor all respective reports received and based on cumulative experience, will re-evaluate the available evidence on an ongoing basis.; Sender's Comments: Pyrexia is assessed as non-serious.  Pyrexia is listed for Vaxelis as per the safety information.  In agreement with the reporter and the current knowledge on Vaxelis (Pyrexia is listed as per safety information), no confounding factors (co-suspect vaccine), no prior medical history of fever reported, and that the event occurred within one day of vaccination and despite the lack of information in this case (other medical history), the causal relationship between Vaxelis and the event Pyrexia is assessed as related.   This single individual case safety report does not modify the benefit/risk balance of this product. Therefore, no change in the label or other measures is recommended at this time. However, the company will continue to monitor all respective reports received and, based on cumulative experience, will re-evaluate the available evidence on an ongoing basis.