1st April 2022

A 14-day-old baby is brought to A&E by his parents

A 14-day-old baby is brought to A&E by his parents. He was born four weeks premature, through normal vaginal delivery, and discharged home after three days in the special care baby unit. His parents are concerned because he has been very irritable today, crying excessively, and running a temperature that they cannot get down with paracetamol. On examination, there is no rash, he is grunting as he breathes, and his posterior fontanelle feels tense. The doctor suspects meningitis.

Select the SINGLE most likely causative organism from the list below. Select ONE option only.