presented with thick runny nose; chronic inflammation of tonsils; positive for Haemophilus B Influenza and Haemophilus B confirmed by respiratory culture; positive for Haemophilus B Influenza; Initial information regarding an unsolicited valid serious case was received from another health professional (nurse) via Agency (Reference number- 00440310) and transmitted on 21-Jan-2021.   This case is linked to case 2021SA032915.   This case involves a 3-year-old male patient who was found positive for Haemophilus B influenza and presented with thick runny nose with chronic inflammation of tonsils (Haemophilus infection with symptoms of rhinorrhea and tonsillar inflammation), after he received PENTACEL.  Medical history, medical treatment, vaccination and family history were not provided. List of concomitants were reported as no other vaccine.   The patient received 4 doses of suspect of DIPHTHERIA/TETANUS/5 HYBRID AC PERTUSSIS/IPV(MRC5)/HIB(PRP/T) VACCINE (1 dosage form, 0.5 mL, lot number: C5316AA, C5308AA, C5342AA and C5506AA, the expiration dates were unknown due to reporter not being able to access that information) via an intramuscular route at an unknown administration site on 02-MAY-2017, 22-JUN-2017, 17-OCT-2017 and 29-AUG-2018 respectively. (reported as: Immunization).  On an unknown date, the patient presented with serious thick runny nose with chronic inflammation of tonsils (Rhinorrhea and Tonsillar inflammation) (unknown latency) following the administration of DIPHTHERIA/TETANUS/5 HYBRID AC PERTUSSIS/IPV(MRC5)/HIB(PRP/T) VACCINE.   On 17-Jan-2021, a respiratory culture was collected and on 21-Jan-2021, the diagnosis of Haemophilus B was confirmed as patient was found positive for Haemophilus B influenza (Haemophilus infection), 3 years 8 months 19 days following the administration of first dose, 3 years 6 months 30 days following the administration of second dose, 3 years 3 months 4 days following the administration of third dose and 2 years 4 months 23 days following the administration of fourth dose DIPHTHERIA/TETANUS/5 HYBRID AC PERTUSSIS/IPV(MRC5)/HIB(PRP/T) VACCINE.  All the reported events were assessed as medically significant.  This was also a case of vaccination failure (unknown latency) as the patient was positive for Haemophilus B influenza, despite being vaccinated with PENTACEL.   Relevant laboratory test results included: Culture - On 17-Jan-2021: the diagnosis of Haemophilus B was confirmed Haemophilus test - On 17-Jan-2021: Positive [positive for Haemophilus B Influenza]  The patient was treated with AMOXIL, but the patient was not responding then he was prescribed a CEFDINIR.  At the time of reporting, the outcome was unknown for all the events.  The reporter also wanted to know if vaccine was resistant to their strain of the virus and would like a call back as soon as possible. Sender's Comments: This case involves a 3-year-old male patient who presented Haemophilus infection with symptoms of rhinorrhea and tonsillar inflammation, after vaccination with PENTACEL. The time to onset is compatible with the Haemophilus infection and unknown with the other reported events. It was also a case of vaccination failure. A respiratory culture confirmed the diagnosis of Haemophilus B. However, no information regarding patient's condition at time of vaccination and immune status was provided. Based upon the reported information, the role of an individual vaccine and vaccination failure cannot be assessed.